# Best rechargeable "D" cell



## 6thtexas (Dec 27, 2011)

What is the best rechargeable "D" cell battery now available? I've got a couple of lanterns that run off "D"s and don't wish to fool with adapters.


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## flydiver (Jan 19, 2012)

Found this request because I'm looking myself. 

Without having any personal experience with most modern D's (and since no one else seems to be weighing in) these have gotten OK reviews in a few places. 
Accupower Evolution D 10000mAh NiMH Low Discharge Rechargeable Batteries

In AA the Imedion have gotten good reviews. Maybe this means these are OK? Again, no personal experience. 
Maha Imedion 2 Pack D Cell 9500mAh NIMH Rechargeable Batteries

I've got some OLD (9/02-like I said, old) Radio Shack 4400 D's that have been great, still work fine. Prior to that I had some RS 4400 NiCads and those things were great!
I tried some Tenergy 5000 NiCads and they were a bust. Only lasted a couple years in the same service all of these batteries get (dive light, ~ 18W for an hour)
Some AccuPower 8500 (8/03) are still functioning but down to maybe 6000. They've been a pretty good product. 
I've got some Titanium 1200 (9/10) that are at best 9000 from the first. A triumph of marketing over honest specs. I was hoping for better. Otherwise they seem OK so far. They will do 2 dives on a single charge and none of the others will. That's what I was after with the higher capacity. 

fly


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## 357mag1 (Jan 20, 2012)

Avoid the AccuEvolution D cells at all cost. The old cells were great, the cells they presently sell are the worst D rechargeable cells I have tested and I've tested a bunch.

The Imedion D cells are not much better.

That leaves us with Tenergy cells which are surprisingly good for the price. Check out all-battery.com for the Premium D cells. They are actually better at holding voltage under load than the original AccuEvolution D cells which were awesome cells.

Avoid the Titanium D cells, while I haven't tested the D cells their C cells are the worst I've tested which leads me to believe their D cells would be poor as well.

Hope this helps


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## jayflash (Jan 20, 2012)

Is the high or low nib the only way to determine whether the AccuE's are new or old? I've a batch of 10 each, C & D cells which seem to be holding their LSD qualities -- at least for moderate drains. Some have posted poor performance at high drains.

I returned about 30 Titanium NiCd cells a couple years ago because they lost capacity after each charge. The sub-C, 1800 mAh, 10C rated Titanium NiCd cells are still holding up in my tools.


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## 127.0.0.1 (Jan 20, 2012)

Maha PowerEx makes the best D rechargeable on the planet
http://www.mahaenergy.com/store/viewitem.asp?idproduct=432

most others are garbage or good fakes with far lower mah than they state.


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## 357mag1 (Jan 20, 2012)

127.0.0.1 said:


> Maha PowerEx makes the best D rechargeable on the planet
> http://www.mahaenergy.com/store/viewitem.asp?idproduct=432
> 
> most others are garbage or good fakes with far lower mah than they state.



It would be nice if you let us know what testing led you to this conclusion. I've thoroughly tested most of the D cells on the market and they all have about the same capacity no matter what rating is on the battery. The big difference is in each cells ability to maintain voltage under a load. So far none have done better than the Tenergy cells in my testing.

I have not tested the Maha D cells as I was told they put their name on Tenergy cells. I do not know this to be fact.


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## bigchelis (Jan 20, 2012)

The absolute best NiMH D cells I think are by Tenergy, but thats because I used them at 15~30A drain on 100watt LED flashlights.


If you have normall sub 5A discharge lanterns, then any will do fine. If you have high drain Lanterns then definitely get the Tenergy D cells since they seem to have less cell sag at high current.

bigC


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## 127.0.0.1 (Jan 20, 2012)

357mag1 said:


> It would be nice if you let us know what testing led you to this conclusion. I've thoroughly tested most of the D cells on the market and they all have about the same capacity no matter what rating is on the battery. The big difference is in each cells ability to maintain voltage under a load. So far none have done better than the Tenergy cells in my testing.
> 
> I have not tested the Maha D cells as I was told they put their name on Tenergy cells. I do not know this to be fact.



lets say I remember some tests but cannot reference them now. don't base any purchases on what I say

my own seem to last and last and last


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## flydiver (Jan 22, 2012)

357mag1 said:


> Avoid the AccuEvolution D cells at all cost. The old cells were great, the cells they presently sell are the worst D rechargeable cells I have tested and I've tested a bunch.
> 
> The Imedion D cells are not much better.
> 
> ...



This helps loads, or at least an opinion. Do you have any data or just anecdotal info? Experience is all I have. My testing has only recently become somewhat useful. All my prior experience/data is how things held up under use. 
The Tenergy 5000 D's that I thought were lousy were NiCads. I use these in the same product (18W dive light) for ~an hour, and recharge them with the a high end hobby charger or a 1/10C wall wart depending on the pack and the time I want to spend. 
Been doing this for more than 12 years, hobby chargers with some basic data I can use are relatively new. Only the Tenergy 5000 NiCads essentially croaked after about 2 years and maybe 20-25 cycles. Just wouldn't hold charge or capacity. Pretty poor. 

You apparently think the Tenergy NiMh (these?) are about the best you've seen so far? 
Any input on the Tenergy 10107 LSD D Centura 8000 mAh 2-Pack Blister Card ($15.95 right now).
With the poor taste of the Tenergy NiCads remaining I need a little reassurance on the product before venturing into that brand again. 

I suspect there must be some kind of capacity inflation vs actual performance going on by marketing like in AA. I've found AA > 2500 to be mostly worthless. Maybe the same thing in D's > what 10,000? The Titanium 12000 certainly are NOT.


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## hank (Jan 22, 2012)

Same question, I'm curious too about the "Centura Low Self Discharge"


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## Aquanaut (Jan 22, 2012)

Have you considered NiCd cells? I have some 15 year old Sanyo KR 4400 D cells. When I last checked capacity of one of the cells, it still had 3865 mAh discharged at 1A. I just looked it up and found them for $8 a cell.


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## 357mag1 (Jan 22, 2012)

hank said:


> Same question, I'm curious too about the "Centura Low Self Discharge"



The Centuras are second for holding their voltage under load. I haven't tested the LSD characteristics yet but if I wasn't planning on leaving my flashlight setting around for 6 months or more I would just go with the Premium cells. They have more capacity and most D nimh don't seem to self discharge as fast as the old nimh AA batteries.

Aquanaut mentions NiCD cells but even the good ones have about half the capacity of the nimh cells. NiCD cells are not very environmentally friendly either if that matters to you.


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## sadtimes (Jan 23, 2012)

I just bought 8 Tenergy D 10,000mah and after a couple of cycles in the charger they all take over 9000mah during a charge.. also they hold up well at 9.5a current draw in a 3d mag SST-90 build


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## 357mag1 (Jan 23, 2012)

flydiver said:


> This helps loads, or at least an opinion. Do you have any data or just anecdotal info? Experience is all I have. My testing has only recently become somewhat useful. All my prior experience/data is how things held up under use.
> The Tenergy 5000 D's that I thought were lousy were NiCads. I use these in the same product (18W dive light) for ~an hour, and recharge them with the a high end hobby charger or a 1/10C wall wart depending on the pack and the time I want to spend.
> Been doing this for more than 12 years, hobby chargers with some basic data I can use are relatively new. Only the Tenergy 5000 NiCads essentially croaked after about 2 years and maybe 20-25 cycles. Just wouldn't hold charge or capacity. Pretty poor.
> 
> ...



No those are not the Tenergy cells I consider the best. If you go to All-battery.com and look at the Premium Tenergy cells those are the ones I consider the best. Personally I won't purchase from the vendor that you linked after spending literally thousands with them and having multiple orders processed incorrectly. The final straw was their refusal to assist with a defective product. Too many good companies out there to put up with that kind of service.

Actually under a 2amp draw all of my Tenergy cells have met or exceeded their capacity labels. The Centura cells may be rated at 8000mah but all of mine have measured right around 8500mah or higher. That is better than the "Original" AccuEvolution cells (which were pretty good cells) even though they are rated for 10,000mah.

The D cells with LSD characteristics that I've tested on my hobby chargers all seem to have around 8500mah when using a 2amp discharge no matter what they claim.

The standard D cell nimhs that I've tested all seem to measure right around 10,000mah using the same discharge current. The big difference is how they maintain voltage under a load. I haven't seen anything yet that beats the Tenergy Premium cells and I have them in lights drawing over 14amps. The next best are the Tenergy cells like you linked and the Centuras.

So my recommendation is to save your money and don't buy the more expensive cells as none of them seem to be worth the extra cash. In fact they are inferior. I learned this the hard way after buying the expensive cells first. If I hadn't ordered a "New" set of AccuEvolutions and instantly noticed my ROP High using 6 D cells was not near as bright I would never had started all this testing and would not have this knowledge.


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## 380long (Jan 24, 2012)

I run Tenergy D cell 10000mAh in my Fenix TK70 and have been pleased so far.


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## JudasD (Jan 25, 2012)

I run the Tenergy Centura 8,000 in my TK70 and have been happy as well. I have only had the light for a short time so i cannot attest to their LSD properties, but i can say that i get close to an hour on turbo :thumbsup:

JD


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## bill_n_opus (Jan 25, 2012)

Glad I read this thread ... some good info.


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## CyberCT (Feb 8, 2012)

JudasD said:


> I run the Tenergy Centura 8,000 in my TK70 and have been happy as well. I have only had the light for a short time so i cannot attest to their LSD properties, but i can say that i get close to an hour on turbo :thumbsup:
> 
> JD



How long does the TK70 run on turbo exactly? On the TK70 thread a user gets an hour on turbo with the Imedion D cells. They might be LSD but that's interesting you get about an hour too on the 8000 mah Tenergys.


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## JudasD (Feb 9, 2012)

CyberCT said:


> How long does the TK70 run on turbo exactly? On the TK70 thread a user gets an hour on turbo with the Imedion D cells. They might be LSD but that's interesting you get about an hour too on the 8000 mah Tenergys.



My very first charge i got 45 minutes. I charged, discharged, charged and then the next day got almost 55 minutes. My Maha said that these batteries discharged at almost 9,000mA. I am sure the Tenergy Premiums would do even better with 10,000mAh. I just wanted the LSD properties so i sacrificed a bit of capacity.

JD


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## CyberCT (Feb 9, 2012)

I think you are following along in the TK70 and F Cell threads too JudasD, so you know I'm hoping for something other than D cells to work good in the TK70. I don't particularly want to us the 4th D cell adapter on the TK70, nor do I want to have the weight of all 4 D cells.

However, if I must, then I'm thinking about going with the Tenergy Premium D Cells at 10,000 mah. I can get 8 of them for $54, will probably have to buy the Maha 8080S though which is expensive. I can use adapters in my MH-C9000 charger so I do tests on each cell to get the mah capacities of each Tenergy and do cell matching like I have with my AA eneloops and Imedions.


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## HIDC (Feb 9, 2012)

Tried Nexcell 9000mAH. Complete garbage from Thomas Distrib. They took care of it well though. Instead, I ordered in a bunch of 2AA->D adapters and that works well in the TK70 for playing.


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## 357mag1 (Feb 9, 2012)

CyberCT said:


> How long does the TK70 run on turbo exactly? On the TK70 thread a user gets an hour on turbo with the Imedion D cells. They might be LSD but that's interesting you get about an hour too on the 8000 mah Tenergys.



CyberCT,
Even though the Imedians are more expensive cells the Tenergy Centura in actual tests I've performed have almost identical capacities (around 8200mah or so). The only diference is the Centura cell maintains a higher voltage under load. 

I've noticed the Tenergy cells are the only ones that seem to be honestly rated at this time.


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## CyberCT (Feb 9, 2012)

I thought that in tests, the Imedions DID have around their rated capacity of 9,5000 mah. Under heavy load like with the TK70 it may be a little different, but for something with less of a heavy load they are good. In another thread, a user did get an hour runtime with the Imedions, did you get an hour with the Tenergy Centura?

The Tenergy Centura is 8,000 mah rated, but the Tenergy Permiums are not LSD and rated at 10,000 mah.


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## 357mag1 (Feb 9, 2012)

CyberCT said:


> I thought that in tests, the Imedions DID have around their rated capacity of 9,5000 mah. Under heavy load like with the TK70 it may be a little different, but for something with less of a heavy load they are good. In another thread, a user did get an hour runtime with the Imedions, did you get an hour with the Tenergy Centura?
> 
> The Tenergy Centura is 8,000 mah rated, but the Tenergy Permiums are not LSD and rated at 10,000 mah.



I've tried just about every D cell rechargable on the market. I have personally tested the Imedions and the ones I purchased from Thomas Distributing when tested with a 2amp load have tested around 8200-8400mah. That is identical to what I get with the Centura D cells.

I've tested the Tenergy Premiums too and they are the best D cells on the market in my opinion.

You are right that under heavier loads like the TK70 on Turbo the Tenergy cells do even better. 

I can't speak to what others have claimed. I can only tell you I've spent a lot of money and time trying to find good quality D Nimh cells when real world use showed me the AccuEvolution cells that use to be great went to crap.


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## JudasD (Feb 9, 2012)

I went with the Centuras based on 357mag1's testing comments and i am a happy camper! They hold great amounts of power! :thumbsup:

JD


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## CyberCT (Feb 9, 2012)

JudasD said:


> I went with the Centuras based on 357mag1's testing comments and i am a happy camper! They hold great amounts of power! :thumbsup:
> 
> JD



The Centuras are LSD batteries am I correct? If I can't find good 32600 batteries that work well (I am interested in buying the TK70 for snorkeling) I might have to go with D cells. I hate to have the extra weight of NIMH instead of LION and I don't really want to use the extender for the 4th D cell but otherwise I like this light and need a good power source for turbo. I particularly wouldn't go snorkeling for much over an hour often anyway. I would think for D cells an LSD cell would be much better to have than a non-LSD cell. D cells take a lot more time and juice to charge than an AA cell so I'm thinking maybe LSD is the only way to go with D cells.


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## 357mag1 (Feb 9, 2012)

The Centuras are LSD. 

From the testing I've done so far even after 6 weeks on the shelf the Tenergy Premium cells still have over 9000mah of energy which is more than any of the LSD cells have fresh from my testing.
So it would really depend on how long you will leave them setting in a light. 

Check novaeproducts.com for 32650 cells. They actually measure 70mm long and two power the TK70 fine. I just made a space to take up the extra room. All of my Novae cells tested over 5500mah after one cycle so they are fairly rated. 

If you had a leak Nimh batteries would be safer than Lithium.


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## CyberCT (Feb 9, 2012)

357mag1 said:


> The Centuras are LSD.
> 
> From the testing I've done so far even after 6 weeks on the shelf the Tenergy Premium cells still have over 9000mah of energy which is more than any of the LSD cells have fresh from my testing.
> So it would really depend on how long you will leave them setting in a light.
> ...



Wait, you have the Novae 32650 cells? And you tested them in your TK70? Another user mentioned that he had those Novae batteries and on turbo his TK70 would stop working (because of the protection circuits I presume). I asked for more information and if he tested those batteries elsewhere, thinking maybe one of them was bad.
I was really disappointed because I thought I finally found 32650s for the TK70 so I could still use the 3D tube and have a lighter flashlight vs having the longer and heavier 4D tube. 
Can you confirm you got the Novae 32650s to work in your TK70 on turbo mode? And if so, what was the runtime?


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## 357mag1 (Feb 9, 2012)

CyberCT said:


> Wait, you have the Novae 32650 cells? And you tested them in your TK70? Another user mentioned that he had those Novae batteries and on turbo his TK70 would stop working (because of the protection circuits I presume). I asked for more information and if he tested those batteries elsewhere, thinking maybe one of them was bad.
> I was really disappointed because I thought I finally found 32650s for the TK70 so I could still use the 3D tube and have a lighter flashlight vs having the longer and heavier 4D tube.
> Can you confirm you got the Novae 32650s to work in your TK70 on turbo mode? And if so, what was the runtime?



I have four of the Novae cells I received on 9Dec11 and just tried all four (2 at a time) in both of my TK70s. They power up and all modes including Turbo work.

Keep in mind the website quotes .6C as the max discharge rate and that works out to 3.3 amps. If I remember correctly the current draw with two cells was right around 4.7amps. That theorectically works out to over an hour of runtime.

As the cells get depleted and loose voltage the light will draw more current because it is regulated. At some point that could cause the protection circuit on the batteries to kick in. I've run one of my TK70s for 10-15 minutes on Turbo using two of these cells and didn't have any issues.

You might want to use the "Contact Us" button on their page as ask at what current draw is their circuit designed to operate.


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## CyberCT (Feb 9, 2012)

Your reply to my quote might have gotten deleted by accident or something


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## 357mag1 (Feb 9, 2012)

CyberCT said:


> Your reply to my quote might have gotten deleted by accident or something



Must have fumble fingered it.


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## CyberCT (Feb 9, 2012)

Wow that's good news! Maybe the other user had a problem with one of his batteries and that's why they didn't work.

Could you perhaps try a runtime test with your TK70 on turbo mode and see how long it takes until the protection circuits kick in and the light turns off? You could submerge half the TK70 in cool water or something so the light doesn't get very hot. THat's what I've done with all my Fenix lights when doing runtime tests on my Eneloop and Imedion AAs, and 18650s. The lights are cool to the touch in the water once the light kicks down to a lesser mode.

If you actually get about an hour runtime on the Novae batteries I'll pull the trigger for a TK70 and those batteries ASAP. I'll have to make an adapter to charge the Novae 32650s in my PIla IBC charger.


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## HotWire (Feb 10, 2012)

I put Imedion cells from Lighthound in my TK70 after using some old, cheap rechargeables. The Imedion cells are wonderful. They last a long time, and they don't lose much energy after storing them for awhile. The Imedion cells brought new life to my TK70. It's a new light again. I use a Maha charger.


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## 357mag1 (Feb 10, 2012)

CyberCT said:


> Wow that's good news! Maybe the other user had a problem with one of his batteries and that's why they didn't work.
> 
> Could you perhaps try a runtime test with your TK70 on turbo mode and see how long it takes until the protection circuits kick in and the light turns off? You could submerge half the TK70 in cool water or something so the light doesn't get very hot. THat's what I've done with all my Fenix lights when doing runtime tests on my Eneloop and Imedion AAs, and 18650s. The lights are cool to the touch in the water once the light kicks down to a lesser mode.
> 
> If you actually get about an hour runtime on the Novae batteries I'll pull the trigger for a TK70 and those batteries ASAP. I'll have to make an adapter to charge the Novae 32650s in my PIla IBC charger.



Unfortunately I don't have time to babysit the light to see when it kicks off the Turbo mode.


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## 357mag1 (Feb 10, 2012)

HotWire said:


> I put Imedion cells from Lighthound in my TK70 after using some old, cheap rechargeables. The Imedion cells are wonderful. They last a long time, and they don't lose much energy after storing them for awhile. The Imedion cells brought new life to my TK70. It's a new light again. I use a Maha charger.



Hotwire,
If I already had the Imedions I would use them but they are over priced and not the best quality D cells out there.


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## CyberCT (Feb 10, 2012)

357mag1 said:


> Unfortunately I don't have time to babysit the light to see when it kicks off the Turbo mode.



 I don't want to buy these cells and have the light kick down from turbo to high in anything less than 35 minutes at least.


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## JudasD (Feb 10, 2012)

CyberCT said:


> I don't want to buy these cells and have the light kick down from turbo to high in anything less than 35 minutes at least.



I would say just remove all doubt and get either the Tenergy Centuras or the Premiums. Cant go wrong with either.

JD


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## CyberCT (Feb 10, 2012)

But I REALLY want a shorter, lighter flashlight. Plus I would only have to pay for the batteries since I can fabricate adapters to get them working in my Pila IBC. 

If I go the D cell route, and plus a charger, it's going to be more expensive, and the flashlight will be heavier and longer.


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## sadtimes (Feb 11, 2012)

This is a super deal and super hard to pass up.. he has 81 of them left (show 81 sets of 8)... He also has another auction with 4 for 15.00 in case you dont need 8

Also posting in the good deals section

http://www.ebay.com/itm/360432953035?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

If this isnt allowed I apologize in advance and please remove the link


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## CyberCT (Feb 11, 2012)

So these are not LSD. I wonder how long the cells will have a charge until dead? If I charge them in early March should I expect them to be completely depleted in early April? I don't want to charge them each month just to keep them from being empty (which damages the cell, correct?)


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## CyberCT (Feb 12, 2012)

Just bought a quantity of 2 (16 total batteries). First I went online and found the Tenergy data sheet of the batteries. They are supposed to have 65% or more charge remaining after one year, stored at 20C. That's LSD enough for me. Ever six months I do the "conditioning mode" for my LSD AA and AAA batteries anyway. That is an insane price!


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## 357mag1 (Feb 12, 2012)

I bought 16 of them too and have been performing discharge tests as a way of cycling the batteries. They seem to be averaging between 7500 - 8100mah. They might improve some but I'm pretty happy with these cells. They rival the Tenergy Premiums for maintaining voltage under a load.

Capacity doesn't hardly seem affected whether discharging at 2amps, 3amps or 5amps. 

I recently let some Premium cells sit for just over 6 weeks. The static voltage measured right around 1.3v which was the lowest of the cells I tested (all others were LSD). The Premiums had only lost about 100mah each from freshly charged tests, about the same as the LSD cells. Best part was they easily beat all other cells in maintaining a higher voltage under load even the Centuras (second best).

Hopefully these cells perform in a similiar manner.
I have some setting charged on the shelf at the moment and will test them in 6 weeks or so.


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## CyberCT (Feb 12, 2012)

Thanks for doing all these tests 357mag1. So the ones that I (and you) just bought are actually just an 8,000 mah battery or less on average? I was expecting more. The Tenergy data sheet says min capacity is 9000 mah. You mentioned though that under load they rival the Tenergy Premiums. Under what load specifically? I will now be purchasing the Fenix TK70. So that will be the "load" that all four of these batteries (in a series) will experience. Which is quite a lot I think. Do you have any tests of the capacites under a load like that?


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## sadtimes (Feb 12, 2012)

CyberCT said:


> Thanks for doing all these tests 357mag1. So the ones that I (and you) just bought are actually just an 8,000 mah battery or less on average? I was expecting more. The Tenergy data sheet says min capacity is 9000 mah. You mentioned though that under load they rival the Tenergy Premiums. Under what load specifically? I will now be purchasing the Fenix TK70. So that will be the "load" that all four of these batteries (in a series) will experience. Which is quite a lot I think. Do you have any tests of the capacites under a load like that?



Using a Triton 2 EQ charger at 3a dischage I found these to be in between 8000-9000mah, when they charge they are about the same.. I have just finished a direct drive SST-90 mag 3d and these are able to provide 10.2-10.5a without any trouble...(using a clamp meter, measurement taken just before the led) 

I have purchased at least 32 of these, 16 of which have made it here and are working just fine, the other 16 are in the mail... 




> Just bought a quantity of 2 (16 total batteries). First I went online and found the Tenergy data sheet of the batteries. They are supposed to have 65% or more charge remaining after one year, stored at 20C. That's LSD enough for me. Ever six months I do the "conditioning mode" for my LSD AA and AAA batteries anyway. That is an insane price!



Yes it is.. these are about 10 bucks each from the normal suppliers..

I have bought from this guy before, he is a liquidator, so once these are gone he wont get anymore.. (at least previous experiences with him anyways)


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## 357mag1 (Feb 12, 2012)

CyberCT said:


> Thanks for doing all these tests 357mag1. So the ones that I (and you) just bought are actually just an 8,000 mah battery or less on average? I was expecting more. The Tenergy data sheet says min capacity is 9000 mah. You mentioned though that under load they rival the Tenergy Premiums. Under what load specifically? I will now be purchasing the Fenix TK70. So that will be the "load" that all four of these batteries (in a series) will experience. Which is quite a lot I think. Do you have any tests of the capacites under a load like that?



So far the highest I've seen is 8100mah and I'm using a Triton 2 EQ as well. My batteries arrived with static voltage readings around .9V and some batteries had less than 7000mah capacity on the first cycle. They have all climbed above 7500mah after a couple of cycles (not gentle ones either). With proper cycling they may continue to improve.

The highest discharge rate I can do is 5amps (Not on the Triton). I've only done a couple of the Premiums and these Standard (Blue) batteries at that rate and so far the Standard batteries seem to be holding right with the Premiums.

Tailcap current with 4 Premium D cells is right at 6.4amps in my TK70s so you should get over an hour of runtime.


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## wheel (Feb 12, 2012)

HIDC said:


> Tried Nexcell 9000mAH. Complete garbage from Thomas Distrib. They took care of it well though. Instead, I ordered in a bunch of 2AA->D adapters and that works well in the TK70 for playing.



I am interested in the AA adapters to substitute for D cells in several 2D Maglights with Malkoff Dropin. The adapters you spoke of are 2AA in each adapter or 1AA. Also, are you pleased with the result using the adapters. Thanks a bunch.


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## CyberCT (Feb 12, 2012)

The Tenergy datasheet says to charge their D cell at 1 amp for 16 hours. Isn't that the "soft charge" mode of the Maha MH-C808M charge at 1 amp? And the regular charge at 2 amp? I thought I read somewhere else on this forum (maybe the TK70 thread) that someone said to use the 2 amp charge for D cells, not the 1 amp charge. ANy thoughts?


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## sadtimes (Feb 12, 2012)

CyberCT said:


> The Tenergy datasheet says to charge their D cell at 1 amp for 16 hours. Isn't that the "soft charge" mode of the Maha MH-C808M charge at 1 amp? And the regular charge at 2 amp? I thought I read somewhere else on this forum (maybe the TK70 thread) that someone said to use the 2 amp charge for D cells, not the 1 amp charge. ANy thoughts?



A general rule of thumb is to charge any NiMH at 0.5C, in this case that is a 5a rate. I know that they will need cycling (normally) before reaching max capacity (at least when they have been sitting for so long) I wonder if the 1a for 16hrs was the initial charge and then you could go to the 0.5C charge.. I have read somewhere these cells can handle up to 8.0a charge rate...


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## Russel (Feb 12, 2012)

I've noticed a couple 10,000mAh NiMH D cell manufactures recommend about 1A for 16 hours as the standard charge rate, and 2A for 7 hours for fast charging. Tenergy recommend 950mA for 16 hours as standard and 1.9A for 7 hours as fast charge. I would be reluctant to charge those cells at 5A. I'm thinking that because of the relatively small surface area with respect to the capacity of these NiMH D cells they can't dissipate heat as well as AA or AAA cells and the 0.5C charge rate may be too high.


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## chewy78 (Feb 12, 2012)

drmalenko said:


> This is a super deal and super hard to pass up.. he has 81 of them left (show 81 sets of 8)... He also has another auction with 4 for 15.00 in case you dont need 8
> 
> Also posting in the good deals section
> 
> ...


 i bought 12 of them, might buy another 8 of them though.


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## CyberCT (Feb 12, 2012)

So it is perfectly fine to charge these D cells in the Maha MH-C808M at the standard rate (2,000 mah) instead of the "soft" mode (1,000 mah)?

I'm thinking of maybe doing two "conditioning" modes per D cell battery in the MH-C808M (to break them in) and then doing a discharge test on my MH-C9000 with modified adapters to charge D-cells. I'm not sure what the maximum discharge rate is for the C9000. That should tell me the capacity of each cell, correct?


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## hank (Feb 12, 2012)

I'm puzzled looking Tenergy's products page:
http://www.tenergy.com/Site/D-NiMH are their button top consumer cells.

Are the blue button top 10,000mah D cells with the big lower case "e" on them an older design, or am I missing something?


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## bruintennis (Feb 12, 2012)

Great thread. I was wondering about D cells too.


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## 357mag1 (Feb 12, 2012)

CyberCT said:


> So it is perfectly fine to charge these D cells in the Maha MH-C808M at the standard rate (2,000 mah) instead of the "soft" mode (1,000 mah)?
> 
> I'm thinking of maybe doing two "conditioning" modes per D cell battery in the MH-C808M (to break them in) and then doing a discharge test on my MH-C9000 with modified adapters to charge D-cells. I'm not sure what the maximum discharge rate is for the C9000. That should tell me the capacity of each cell, correct?



Unless i needed them in a hurry I would charge at the slower rate. The faster you charge a cell the more likely you are to shorten the life span. 
I would definitely condition them at least once and twice would probably be better if you have the time.

The C9000 has a max discharge rate of 1amp and yes it should give you the capacity.


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## 357mag1 (Feb 12, 2012)

hank said:


> I'm puzzled looking Tenergy's products page:
> http://www.tenergy.com/Site/D-NiMH are their button top consumer cells.
> 
> Are the blue button top 10,000mah D cells with the big lower case "e" on them an older design, or am I missing something?



Yest the Blue cells are the older design. They appear to still be available on all-battery.com but at pretty much the same price I would get the Premiums.


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## CyberCT (Feb 12, 2012)

357mag1 said:


> Unless i needed them in a hurry I would charge at the slower rate. The faster you charge a cell the more likely you are to shorten the life span.
> I would definitely condition them at least once and twice would probably be better if you have the time.
> 
> The C9000 has a max discharge rate of 1amp and yes it should give you the capacity.



For the C808M, should I do the "conditioning mode" with the "soft" mode? Apparently you can do both with this charger? That supposedly takes waaayy too long from what I've read for D cells. Since the capacity is much higher on D cells does it really matter if I just do it in normal mode?

Also, doing two "conditioning mode" cycles for each battery won't be harmful to the battery, will it?

Does the 808M cycle when I insert a battery (charge if needed, then discharge, charge) or does it just charge until the battery is fully charged? I want to do some cycling.


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## CyberCT (Feb 12, 2012)

357mag1 said:


> Yest the Blue cells are the older design. The appear to still be available on all-battery.com but at pretty much the same price I would get the Premiums.



Tenergy seems to be discontinuing these D cells. The ebay link in this thread has a great deal on them.


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## 357mag1 (Feb 12, 2012)

CyberCT said:


> For the C808M, should I do the "conditioning mode" with the "soft" mode? Apparently you can do both with this charger? That supposedly takes waaayy too long from what I've read for D cells. Since the capacity is much higher on D cells does it really matter if I just do it in normal mode?
> 
> Also, doing two "conditioning mode" cycles for each battery won't be harmful to the battery, will it?
> 
> Does the 808M cycle when I insert a battery (charge if needed, then discharge, charge) or does it just charge until the battery is fully charged? I want to do some cycling.



I don't have an C808M yet (I should in a few more days) so have no experience to answer questions relating to that unit.
Best for batteries when conditioning to use a slow charge and discharge. 2000mah AAs take over 30 hours on the C9000 if I remember correctly. 

If you are gettiing 16 cells mark each cell and charge them all. Throw 12 of them, 4 at a time in the TK70 and play around with it for 15 minutes with each set. Charge those twelve up again and start the slow conditioning cycle on the other 4. That should keep you in power until they complete. Then repeat the process until you have conditioned them all.


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## CyberCT (Feb 12, 2012)

I just bought one too. Hopefully this charger, the batteries, and the TK70 will arrive this week.


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## hank (Feb 13, 2012)

uh, oh: an earlier CPF thread:
http://www.candlepowerforums.com/vb...ed!-What-Now&p=3561799&viewfull=1#post3561799
"Maha MH-C808M Charger Melted! What Now??
When I was researching this charger, I found two reviews about it catching on fire..."
One of them with Tenergy 10,000 NiMH D cells.

Of course there's always going to be one or two problems out of tens of thousands.


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## JudasD (Feb 13, 2012)

hank said:


> uh, oh: an earlier CPF thread:
> http://www.candlepowerforums.com/vb/showthread.php?296907-My-Maha-MH-C808M-Charger-Melted!-What-Now&p=3561799&viewfull=1#post3561799
> "Maha MH-C808M Charger Melted! What Now??
> When I was researching this charger, I found two reviews about it catching on fire..."
> ...



Those reports are from over a year ago. Chances are maha has made some changes since then.

JD


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## hank (Feb 15, 2012)

> Maha MH-C808M
I don't find mention of changes at Maha; I've emailed to ask. It's a switched-mode power supply built in the case, not a wall wart, so overheating could be typical failure -- Wikipedia says what I've read elsewhere, that "switching adapters are more likely to fail than the older type" and mentions a variety of ways it happens.
So it goes; rare anyhow. If I hear anything from Maha I'll mention it, but I'll put it in a charger topic so not to get further off track here.

Meanwhile, on topic -- I just got my eight Tenergy 10,000A D cells (blue with the big lower case "e").

Checked the first four as they came out of the shrinkwrap, 
about 0.2, 0.2, 0.4, and 1.0v showing. I've got a CCrane charger that handles D size, I'm using it on the first four. Will follow up.


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## CyberCT (Feb 15, 2012)

Just got my 16 in the mail today. They are the same blue 10,000 mah with the lowecase "e" as you hank. With my voltmeter the lowest was 0.92 and the highest was 1.08. I also got my Maha MH-C808M in the mail today  so I have 8 charging in "soft mode" which is 1 amp rate, which Tenergy recommends.

Are you sure they read that low? I didn't think alkalines could output that low of a voltage. What I found interesting is that there was no batch that was really different that the other. Of the 4 x 4 packaged cells, each pack had 1 or 2 over a volt and 2 or 3 that were under. I was expecting to see one package have all over 1 volt and another package to have all under a volt.


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## CyberCT (Feb 15, 2012)

I just checked the charging and both batteries and charger are cold to the touch (my basement is probably 65ish degrees year round). All batteries right now have 2 of the 3 bars visible and flashing. When I inserted all the batteries at first, only 1 of the 8 had 0 of 3 bars visible. The other 6 had 1 bar and 1 even started charging with 2 bars.


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## hank (Feb 15, 2012)

Those first numbers came from the CCrane's battery analyzer mode. 
On the other hand, it's already telling me it's up to trickle charge mode 
-- way less time than I'd expect if the cells were that low. So, maybe that analyzer voltage was low.

I don't see how I could've messed up measuring it, it's just put in one cell and push the button.
But I've screwed up simpler tasks on occasion.

While that's charging those four, I've now checked the second four right out of the shrinkwrap with one cheap multimeter -- three at about 0.9 and one at 0.7, plus or minus a hundredth.
So that's better. I've double checked with my other cheap multimeter and got consistent numbers; it runs about 0.1 lower but that was consistent across all four.

Once the CCrane is finished with the first four, I'll see what how it reads the second four.
Could well be that measure is running low, I don't think I ever checked its accuracy on that mode.

---- EDIT -- ok, the CCrane showed it finished charging (it has one indicator for all four, and to be fair does say it's best if all the cells are at about the same starting level).
Using the CCrane's Analyze function then, the three cells that had started at 0.2-0.4v originally show as 1.35 or 1.37v, all five bars.
And a cheap multimeter shows them as 1.36, 1.36, 1.35v.

The one cell that had been 1.0 originally now shows as 3 of 5 bars and about 1.2v. So I'm putting it back on charge and will see if it comes up.


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## chewy78 (Feb 15, 2012)

i got 12 of those blue10,000 tenergys off ebay and measured from .88- .91 volts on mine. I have 6 of the ones with the highest voltage reading with my sears dmm charging at one amp on my maha charger to use for a portable radio.


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## hank (Feb 15, 2012)

Second shrinkwrapped batch of four Ds -- which showed three at about 0.9 and one at about 0.7 on the multimeter -- tested on the CCrane 'Analyze' function at much less, 0.14, 0.17, 0.17, and 0.34. So something's odd there. This time I'll try charging just two at a time on the CCrane, having belatedly found the note at their website saying the charger (500ma 12v power supply) may not handle four at a time for high rated large cells.

Oddity -- holding these D cells with the multimeter probes, the voltage shown slowly and steadily increases over time. Do the batteries "wake up" when first tested?


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## CyberCT (Feb 15, 2012)

How long did it take you to charge them? Mine have been charging for almost 5 hours and might be up to the 3rd of 3 bars now on my charger. But I haven't checked it in 40 minutes.


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## chewy78 (Feb 15, 2012)

My first 12 d tenergy d cells i ordered of off ebay for 24.99 are charging nicely in my maha 808. I also ordered another 8 tenergys off ebay. Right now i think they are the best battery for the money/ bang for the buck.


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## 357mag1 (Feb 16, 2012)

My 16 cells all showed between just below .8v to just over 1v right out of the shrink wrap.


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## hank (Feb 16, 2012)

Charging just two in the CCrane took a couple of hours -- up to 1.37 and 1.38v. So I suspect it terminated early when I was trying four at a time. I'll check them again tomorrow.
Good enough to convince me to buy more of these cells while they're available.

Then I'll want a better charger ....


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## 357mag1 (Feb 16, 2012)

CyberCT said:


> How long did it take you to charge them? Mine have been charging for almost 5 hours and might be up to the 3rd of 3 bars now on my charger. But I haven't checked it in 40 minutes.



Soft charge mode is 1amp per hour so you are looking at around 8 hours.


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## CyberCT (Feb 16, 2012)

357mag1 said:


> Soft charge mode is 1amp per hour so you are looking at around 8 hours.



Yes, that's what I figured. I went to bed and the charging was 5.5 hours in. They were all charged when I woke up this morning. I put the second set of 8 on the charger. Hopefully they should be charged when I come home and my TK70 will be at the doorstep! I'll have to rig up my D cell to AA cell setup to use the C9000 to do a "discharge" test of each battery and start getting their mah numbers so I can match my D cells like I have with my AAAs and AAs.


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## jayflash (Feb 16, 2012)

hank said:


> Charging just two in the CCrane took a couple of hours -- up to 1.37 and 1.38v. So I suspect it terminated early when I was trying four at a time. I'll check them again tomorrow.
> Good enough to convince me to buy more of these cells while they're available.
> 
> Then I'll want a better charger ....



Hank, if your CCrane is like mine, it share total charging current between all bays. One cell should charge at about 1.5 amps and each additional cell will evenly divide that -- unless our chargers operate differently. The same is true for the discharge or analyze function. To obtain the slowest discharge rate, put in four cells. To get the highest charge rate, do the opposite and install only one cell.

It seems that your cells need several charge/slow discharge cycles, because your charge time is way too fast.


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## hank (Feb 16, 2012)

Thanks Jayflash -- I've got a quite old CCrane (repaired the springs after they failed a while back); not sure if the newer ones are any different about charging. 

The manual for it does mention needing several cycles. I'm on my first cycle for these batteries, so expect them to shape up after a few cycles.


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## 357mag1 (Feb 16, 2012)

CyberCT said:


> Yes, that's what I figured. I went to bed and the charging was 5.5 hours in. They were all charged when I woke up this morning. I put the second set of 8 on the charger. Hopefully they should be charged when I come home and my TK70 will be at the doorstep! I'll have to rig up my D cell to AA cell setup to use the C9000 to do a "discharge" test of each battery and start getting their mah numbers so I can match my D cells like I have with my AAAs and AAs.



After doing all of my discharge tests multiple times to make sure my broken MD-3000 wasn't causing any erroneous readings I have four of the Tenergy Blue batteries staying just below 7000mah and one more hovering around 6000mah. These are all in the Maha 808 going through a conditioning cycle to see if they will come up any. All of them have been through at least 4 or 5 charge/discharge cycles so I don't expect to see much if any improvement.

These batteries would be fairly rated at around 7500mah as that seems to be about the median for 16 of them. Guess that is why they came out with the Premium replacement. The good news is they seem to hold their voltage just as well as the Premiums under load. I would take these over the garbage AccuEvolution cells any day.

Just to keep in in perspective the Tenergy Premium batteries I own vary in capacity readings from around 9000mah to about 10,400mah. Chinese batteries always seem to have a larger variance. If we could get a Japanese company or "Quality" American company to develope some D Nimh cells we would have some killer Deeees!!!


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## CyberCT (Feb 16, 2012)

357mag1 said:


> After doing all of my discharge tests multiple times to make sure my broken MD-3000 wasn't causing any erroneous readings I have four of the Tenergy Blue batteries staying just below 7000mah and one more hovering around 6000mah. These are all in the Maha 808 going through a conditioning cycle to see if they will come up any. All of them have been through at least 4 or 5 charge/discharge cycles so I don't expect to see much if any improvement.
> 
> These batteries would be fairly rated at around 7500mah as that seems to be about the median for 16 of them. Guess that is why they came out with the Premium replacement. The good news is they seem to hold their voltage just as well as the Premiums under load. I would take these over the garbage AccuEvolution cells any day.
> 
> Just to keep in in perspective the Tenergy Premium batteries I own vary in capacity readings from around 9000mah to about 10,400mah. Chinese batteries always seem to have a larger variance. If we could get a Japanese company or "Quality" American company to develope some D Nimh cells we would have some killer Deeees!!!



Man, that is disappointing! At first I was expecting 10,000 mah as advertised. Then read on here that realistically they are more like 8,000 which is not toooo bad. But anything below that, well now that's crap. My modded Rayovac lanterns take D cells but I have been using the AA to D cell adapters. At 1.4a on the highest mode for an XML, the higher capacity cells would clearly win here, which is what I initially wanted - runtime.

I bought some stuff to make adapters for my D cells to fit into my Maha MHC9000. SO hopefully I'll have it rigged up tonight. What should I do to test the mah values of mine? Just stick them in and discharge at 1 amp for each cell? it would take about 8 hours I presume.


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## 357mag1 (Feb 16, 2012)

I would say you are looking at approximately 8 hours to discharge a cell. 

Remember my tests are at 3 and 5amps to more closely simulate how I use these batteries. 

At about $3.13 a cell shipped to our door I'm still pretty happy. You have to figure at that price they must have been old stock that had sat around for quite some time.

I paid a whole lot more for my AccuEvolution cells and they made my incadescent light (ROP HI) look sick. The cells were not even usable for the application. These Tenergy Blue cells run it as bright as any cell I've used and do it for over 1hr 35mins.

These Blue cells will run my newer TK70 on Turbo using 3 cells the AccuEvolutions sag so bad it drops to high in about 23 seconds.


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## CyberCT (Feb 16, 2012)

Two of the cells are still "soft" charging on my Maha. They have been charging for 13 hours now. I went to home depot and bought a wooden dowel that was the closest size to an aa battery to make an adapter for my C9000. THe dowell was a little too thick and I finally got irritated after my 3rd try to make it fit in there with my copper wires that I gave up. I'll have to figure out another way to get an adapter to work so I can start doing battery matching with the Tenergys.

EDIT: The last two cells took about 13.5 hours to charge. I took them off the charger. With my volt meter I quickly checked these 8 that just came off the Maha, and the 8 that came off yesterday. The range of the 8 charged today was 1.39 to 1.42. Yesterdays was 1.35 to 1.4.

Amazon has multiple reviews of these batteries, and I forget where the link is but these were tested with other D batteries and the capactiy came up as a smuge under 8,000 mah. The Amazon reviews seem to be both good and bad, with the worse reviews being most recent. No doubt QA/QC has sunk, but there seem to be good and bad batches of these batteries.

http://www.rechargeable-battery-rev...battery-tests/d-nimh-battery-performance.html

I ended up buying a pack of those AAA to AA adapters so I will simply wire them up as a dummy cell to my D cell holders that I will have to modify (from series to individual) from Radioshack so I can do discharge tests. I have a feeling that cell matching with these batteries is an absolute must.

I'm not sure the maximum discharge capability of the C9000 but I'll have to check. I could do multiple tests per battery 1 amp, then 2 amp, then 3 amp if it's available. This would probably take a while to do but meh. I bought the TK70 for snorkeling in the late spring so I won't really be using the TK70 much beforehand.


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## sadtimes (Feb 17, 2012)

I have purchased 36 of the batteries from ebay, all of them came out of the shrink wrap between .899 - 1.08v... I started them all of with a charge cycle to wake em up, then cycled them through a 3a discharge and, some at 5a charge, and some at 2a charge.. I have found they all have over 8000mah.. My triton2 charger has actually "mah'ed" out at 9900mah on a couple of charge cycles (most of these were with 8 cells or more in the charge loop) but with 4 cells discharging/ charging at one time I find that 8500-9500mah is the norm with most of them being over 9000mah... 

and its already been said once, at just over 3.00 dollars a cell shipped, you really can not complain even a little bit if they are less than 10,000mah... lol


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## 357mag1 (Feb 17, 2012)

CyberCT said:


> Two of the cells are still "soft" charging on my Maha. They have been charging for 13 hours now. I went to home depot and bought a wooden dowel that was the closest size to an aa battery to make an adapter for my C9000. THe dowell was a little too thick and I finally got irritated after my 3rd try to make it fit in there with my copper wires that I gave up. I'll have to figure out another way to get an adapter to work so I can start doing battery matching with the Tenergys.
> 
> EDIT: The last two cells took about 13.5 hours to charge. I took them off the charger. With my volt meter I quickly checked these 8 that just came off the Maha, and the 8 that came off yesterday. The range of the 8 charged today was 1.39 to 1.42. Yesterdays was 1.35 to 1.4.
> 
> ...



The C9000 is limited to 1amp discharge rate. You can go less in increments of 100ma but not more.


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## chewy78 (Feb 17, 2012)

im gonna have to get some d cell holders and maybe some adapters to test mine. on my c9000


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## CyberCT (Feb 17, 2012)

357mag1 said:


> The C9000 is limited to 1amp discharge rate. You can go less in increments of 100ma but not more.



357mag1, what battery charger do you have, where you can measure the D cells' mah values from various discharge rates?


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## 357mag1 (Feb 17, 2012)

CyberCT said:


> 357mag1, what battery charger do you have, where you can measure the D cells' mah values from various discharge rates?



I use hobby chargers to test battery capacity. I have two, one is a Turnigy AccuCell-8 that can discharge at a rate up to 5amps and the other is a Triton2 EQ that is limited to a discharge rate of 3amps. Either unit can charge or discharge Nimh, NiCad, Lithium and Lead Acid single cells or battery packs.


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## 357mag1 (Feb 17, 2012)

drmalenko said:


> I have purchased 36 of the batteries from ebay, all of them came out of the shrink wrap between .899 - 1.08v... I started them all of with a charge cycle to wake em up, then cycled them through a 3a discharge and, some at 5a charge, and some at 2a charge.. I have found they all have over 8000mah.. My triton2 charger has actually "mah'ed" out at 9900mah on a couple of charge cycles (most of these were with 8 cells or more in the charge loop) but with 4 cells discharging/ charging at one time I find that 8500-9500mah is the norm with most of them being over 9000mah...
> 
> and its already been said once, at just over 3.00 dollars a cell shipped, you really can not complain even a little bit if they are less than 10,000mah... lol



Just because your charger pushed 9900mah to a cell doesn't mean that cell has that capacity. A high quality battery like the Eneloop will have a capacity close to what the charger pushes into it but these cheaper Chinese cells always seem to take more to charge than they deliver in capacity.

As an example I performed some AAA test on the C9000 last night. Eneloop AAAs took around 825mah to fully charge. The Rayovac AAA cells took over 900mah on every cell and some well over that. The Eneloops always show more capacity when discharged than the Rayovacs.

Something to keep in mine.


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## CyberCT (Feb 17, 2012)

357mag1, I appreciate your feedback and help.

I'm learning, and think I finally have an idea of what's going on here. Confirm I do or correct me where I don't. I'm still learning and have picked up bits & pieces over the last two years but think I got it:

There are different mah values: 

1) Charge capacity of a battery is how much charge it can take from the charger in mah, which will usually be the the highest capacity of the battery. 

2) Discharge capacity, which is how much mah a battery can produce for a load. That value will be lower than the charge capacity. Now, for the discharge capacity, the discharge capacity mah values can vary depending on the load or rate of discharge. Let's use an eneloop. The charge capacity might be 2,000 mah. Under a .2 amp load, the battery might produce 1,950 mah. Under .5 amp load, the battery might produce 1,850 mah. Under a 1 amp load, the battery might produce 1,700 mah.

3) The amount of voltage a battery can supply under load. A NIMH battery such as an eneloop is rated at 1.2v. now let's say there is a .5 amp load on the battery. If it produces about 1.15v and 1,850 mah that is better than another AA battery that produces, at .5 amps load, 1.05v but say 1,950 mah? I'm still a little confused about this a little.

Would it be safe to say that a battery with a stated capacity that matches closely its discharge capacity is a good quality battery? Like if a D battery can take 10,000 mah from a charger, but as soon as a load of say 1 amp hits the battery it drops to 8,000 mah capacity, that cell isn't as high quality as a cell that is stated at 9,000 mah capacity but produces 9,000 capacity under load?

When you mentioned that your blue Tenergy cells were around 7,000 mah capacity, you were doing a discharge test of each at what, 4 amps? If you did a 1 amp discharge test should you expect a capacity of more like 9,000 mah?

Just curious, what capacity did the Eneloops show on your C9000 vs the Rayovacs, when you did the discharge?
And which of those two chargers you mentioned do you like better?


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## hank (Feb 17, 2012)

357mag1, can you describe exactly how you're testing D cells with the Turnigy?
I've got an Accucel-6 now and can probably set it up the same way you're doing and compare.
I've only used it with single cells, never with more than one at a time.

I was wondering if the Accucel-6 can handle multiple batteries if set up properly to do effectively the same charge and discharge as the Maha D-cell charger others are using.


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## jayflash (Feb 17, 2012)

Cyber, maybe a bit more info will be useful. It seems there are trade offs and compromises for most things. Ideally, high capacity, good voltage maintenance under high drain, low self discharge, long cell life, and low price, could all be found in one cell. You might find most of those features, but at a higher or premium price. 

Maintaining voltage around 1.25v at loads of ~5 or more amps might be one indication of good quality cells. My AccuEvolution D & C cells are holding their LSD properties after one year and voltage is good, but I only load them to <2 amps. Some 7Ah cells could perform better than other 10Ah cells. 

I depend on discharge capacity to more accurately reflect my actual use. Charging capacities may be up to ~30% higher than actual due to, say, only a 70% charging efficiency. 

It would be nice if large rechargeable cells had warranties. There's potential to spend hundreds on cells that only last a couple years or drop off in performance in less time.

BTW, my RayOVac Hybrids of four years are all deteriorating. My four year old "Duraloops" have lost only 100mAh or so, and are maintaining good voltage under loads of an amp or less.


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## CyberCT (Feb 17, 2012)

Hmm. So in 10 years from now, would it be safe to say my rechargeables are pretty much worthless? I understand that over time they degrade, but thought that in at least 6 years from now, they would still perform similarly (by doing a break-in cycle once a year) I don't use the cells as much as I originally intended.


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## chewy78 (Feb 17, 2012)

jayflash said:


> Cyber, maybe a bit more info will be useful. It seems there are trade offs and compromises for most things. Ideally, high capacity, good voltage maintenance under high drain, low self discharge, long cell life, and low price, could all be found in one cell. You might find most of those features, but at a higher or premium price.
> 
> Maintaining voltage around 1.25v at loads of ~5 or more amps might be one indication of good quality cells. My AccuEvolution D & C cells are holding their LSD properties after one year and voltage is good, but I only load them to <2 amps. Some 7Ah cells could perform better than other 10Ah cells.
> 
> ...


 my older duraloops are performing pretty much new like the day i bought them too. It would be interesting how long these blue label d cell tenergys would last with proper maintenance.


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## CyberCT (Feb 17, 2012)

Just speaking out loud as I'm further learning / understanding this stuff:

In a regulated light like the TK70, it needs 9.6 amps I think. So with 4 D cells that is 2.4 amps per D cell. I think it needs like 4.8v so each cell is providing its correct 1.2v. But with under that heavy load, if a cell is not capable of producing enought volts per amperage drain, it will cause the light to kick down from turbo to high (the light's driver does the kick down as soon as not enough volts from the battery pack is not avaiable anymore.


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## willieschmidt (Feb 17, 2012)

hank said:


> 357mag1, can you describe exactly how you're testing D cells with the Turnigy?
> I've got an Accucel-6 now and can probably set it up the same way you're doing and compare.
> I've only used it with single cells, never with more than one at a time.
> 
> I was wondering if the Accucel-6 can handle multiple batteries if set up properly to do effectively the same charge and discharge as the Maha D-cell charger others are using.


The Accucel-6 has a 1A max discharge vs Accucel 8150 5A but I could be wrong. I concur that my 16 Marrsinc blue D cells have never exceeded 9500ma averaging closer to 8600ma. My 8 premium white Tenergy cells avg 10,500ma. Biggest bang for the buck Marrs blue Ds. On Big Chelis endorsement I purchased the Tenergy Ds and can attest to their high draw low sag capabilities. My PT120 green will pull a 25A+ with hot off the charger 4 D cells via direct drive.


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## CyberCT (Feb 17, 2012)

Wow, that's at least a 6.3 amp draw per D cell! And you're talking about the blue Tenergy D cells referenced in later in this thread?


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## willieschmidt (Feb 17, 2012)

I did that with white cells. Have pulled 20A+ with blue cells with in an hour off the charger. Actually these numbers might be conservative. IIRC read that Lambda has pulled 30A from these cells in 4D configuration.


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## 357mag1 (Feb 17, 2012)

CyberCT said:


> 357mag1, I appreciate your feedback and help.
> 
> I'm learning, and think I finally have an idea of what's going on here. Confirm I do or correct me where I don't. I'm still learning and have picked up bits & pieces over the last two years but think I got it:
> 
> ...



CyberCT,

You pretty much have a handle on it with the exception of the amount of mah a battery takes when charging. Lesser quality batteries always seem to take more mah during charge than they can ever deliver under a load. I think it may have something to do with lesser quality cells being harder for the charger to find a termination point but don't really know.

My discharge tests were at 3 and 5amps. All the batteries were done at 3 and about half at 5. I didn't keep doing the 5amp test because there did not appear to be any difference in capacity between the rates. I haven't seen where quality nimh cells vary much in capacity if the load is kept reasonable for the cell. 

Try this test with your C9000 and two Eneloops of similiar capacity. Discharge one at 1amp and one at 200ma and see how much difference in capacity you get. I wager little to none. At least that was my experience.

The Eneloop and Rayovac AAA had been setting about 3-4 months. I didn't write it down but going from memory the Eneloops were all 640 - almost 700mah and the Rayovacs averaged around 540mah. The Eneloops had a significantly higher voltage during the discharge cycle.

I like the Triton2 EQ better but it is a $170 charger compared to $46 for the Accucell. If I were to do it again I would buy the FMA PowerLab 8 v2 from Progressiverc. Buying quality only hurts once.


----------



## chewy78 (Feb 17, 2012)

CyberCT said:


> Just speaking out loud as I'm further learning / understanding this stuff:
> 
> In a regulated light like the TK70, it needs 9.6 amps I think. So with 4 D cells that is 2.4 amps per D cell. I think it needs like 4.8v so each cell is providing its correct 1.2v. But with under that heavy load, if a cell is not capable of producing enought volts per amperage drain, it will cause the light to kick down from turbo to high (the light's driver does the kick down as soon as not enough volts from the battery pack is not avaiable anymore.


 9.6 amps per cell in a 4 cell configuration ? theoretically if you had 3 cells on the tk70, amperage goes up 33% under load to supply the watts needed? to around 12.8 amps? Or are my calculations a** backwards?


----------



## CyberCT (Feb 17, 2012)

chewy78 said:


> 9.6 amps per cell in a 4 cell configuration ? theoretically if you had 3 cells on the tk70, amperage goes up 33% under load to supply the watts needed? to around 12.8 amps? Or are my calculations a** backwards?



No, it's 9.6 amps total. So divide that by 3 for 3 cells (3.2a), and 4 for 4 cells (2.4a).


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## CyberCT (Feb 17, 2012)

357mag1 said:


> My discharge tests were at 3 and 5amps. All the batteries were done at 3 and about half at 5. I didn't keep doing the 5amp test because there did not appear to be any difference in capacity between the rates.



At the moment I only have my C9000. Once I have my rig set up so I can discharge my Tenergy Ds at 1 amp max, I will do a few recharge, and then discharge tests per cell. Then I will battery match the best four, the 2nd best 4, the 3rd best 4, and then the last worst 4. So these results are based on a 1 amp discharge. If I could do a 3 amp discharge, should I expect the matched batteries to perform comparitevly? Like should I expect the best 4 performing under a 1 amp draw to perform the best under a 3 amp draw? Or would it completely change? Like one of the best at 1 amp draw is 1 of the worst under a 3 amp draw.


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## JudasD (Feb 17, 2012)

chewy78 said:


> 9.6 amps per cell in a 4 cell configuration ? theoretically if you had 3 cells on the tk70, amperage goes up 33% under load to supply the watts needed? to around 12.8 amps? Or are my calculations a** backwards?



The tk70 uses somehwere between 30 to 35watts on turbo. just divide that number by the total voltage of the cells to see what the amps needs to be. When the 4 cells are fresh it uses about 7.2 amps.

JD


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## chewy78 (Feb 17, 2012)

right o


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## 357mag1 (Feb 17, 2012)

CyberCT said:


> Just speaking out loud as I'm further learning / understanding this stuff:
> 
> In a regulated light like the TK70, it needs 9.6 amps I think. So with 4 D cells that is 2.4 amps per D cell. I think it needs like 4.8v so each cell is providing its correct 1.2v. But with under that heavy load, if a cell is not capable of producing enought volts per amperage drain, it will cause the light to kick down from turbo to high (the light's driver does the kick down as soon as not enough volts from the battery pack is not avaiable anymore.



CyberCT,

Current in series is common so whatever current is at the tailcap all cells are felling that draw. In the case of the TK70 all three cells are feeling the 9.84amp draw (from my test). With 4 cells it drops to 6.25amps and again each cell has that current drawn through it.

My Newer TK70 draws 10.7amps on 3 cells and 7.2amps with 4 cells.


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## CyberCT (Feb 17, 2012)

ok thanks for that clarification. I wonder why the new TK70 draws more from the cells than the old one?


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## 357mag1 (Feb 17, 2012)

CyberCT said:


> ok thanks for that clarification. I wonder why the new TK70 draws more from the cells than the old one?



The newer one appears slightly brighter on Turbo. It might just be variance in driver boards and LEDs. After 30+ years in the field nothing in electronics comes out exactly the same. Kind of like snow flakes. 

I have a chart inside an Open Office (Open Source, not Microsoft) I could send you via Email. It list the current draw for both TK70s and my TK60 using various battery configurations. I've tried posting it on here but have not had any luck (Format gets messed up).


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## CyberCT (Feb 17, 2012)

Email received! thanks


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## JudasD (Feb 17, 2012)

357mag1 said:


> CyberCT,
> 
> Current in series is common so whatever current is at the tailcap all cells are felling that draw. In the case of the TK70 all three cells are feeling the 9.84amp draw (from my test). With 4 cells it drops to 6.25amps and again each cell has that current drawn through it.
> 
> My Newer TK70 draws 10.7amps on 3 cells and 7.2amps with 4 cells.



Do you recall what the serial number variance is on the old vs. new lights? Just trying to get an idea of what newer would mean. Neither of these are a TK70S right?

Thanks,
JD


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## 357mag1 (Feb 17, 2012)

JudasD said:


> Do you recall what the serial number variance is on the old vs. new lights? Just trying to get an idea of what newer would mean. Neither of these are a TK70S right?
> 
> Thanks,
> JD



Both of my TK70s run on D cells. I believe the TK70S uses Lithium cells by design but don't know.
My original TK70 is serial F46H9600215 and the newer one is F46H9C00505.

I believe there was a circuitry change in there somewhere but have no idea when or where in the serial numbers it came about. 

Besides drawing more current and looking slightly brighter the newer version also has this difference. No matter what mode it is in when you unscrew the tailcap the new light comes on in low when you first put fresh batteries in and fire it up. I used to think the older light came on in Turbo after a battery change but that was just the mode I had it in most of the time. It actually remembers the last mode used and comes on in that mode after changing out batteries or loosening and securing the tailcap.

So the older light will remember the last selected mode when changing batteries and the new always starts back at low. 

My two TK70s are the only ones I've ever seen or handled so maybe one of my lights has issues but I don't think so. They appear to have slightly different circuitry. Maybe one of our Fenix distributors could shed some light on any TK70 circuitry changes.

Hope that info helps.


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## chewy78 (Feb 17, 2012)

CyberCT said:


> Just speaking out loud as I'm further learning / understanding this stuff:
> 
> In a regulated light like the TK70, it needs 9.6 amps I think. So with 4 D cells that is 2.4 amps per D cell. I think it needs like 4.8v so each cell is providing its correct 1.2v. But with under that heavy load, if a cell is not capable of producing enought volts per amperage drain, it will cause the light to kick down from turbo to high (the light's driver does the kick down as soon as not enough volts from the battery pack is not avaiable anymore.



wrong! every cell puts out equal amps:nana::nana:


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## JudasD (Feb 17, 2012)

357mag1 said:


> Both of my TK70s run on D cells. I believe the TK70S uses Lithium cells by design but don't know.
> My original TK70 is serial F46H9600215 and the newer one is F46H9C00505.
> 
> I believe there was a circuitry change in there somewhere but have no idea when or where in the serial numbers it came about.
> ...



This is very interesting. My TK70 acts like your old one and has the same preface of the serial number. I suppose i have one of the old ones. One thing is that if i leave the batteries out long enough it will default back to low. But if i just undo the tailcap and then reconnect, it will go back to the last used mode. This is a bummer. Kinda wish i had a new one. 

JD


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## CyberCT (Feb 17, 2012)

Hmm I'll have to do that test when I get mine in the mail (hopefully tomorrow). I think shortly after the TK70 was released people started complaing about the light only selecting low mode or some issue. So maybe a flood of returns caused Fenix to do a quick and quiet redesign?


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## 357mag1 (Feb 18, 2012)

JudasD said:


> This is very interesting. My TK70 acts like your old one and has the same preface of the serial number. I suppose i have one of the old ones. One thing is that if i leave the batteries out long enough it will default back to low. But if i just undo the tailcap and then reconnect, it will go back to the last used mode. This is a bummer. Kinda wish i had a new one.
> 
> JD



JD,
I'm trying that test on my older one. I will leave the cap off for a while and see if it drops back to low mode.

It just takes money to get a new one!!!

If you would be interested I just found a place to get new in the box Fenix lights at awesome prices. The guy is stateside and awesome to work with. Wish I would have known about this guy before CyberCT purchased his TK70. Probably could have saved him some cash.


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## LIGAF (Feb 18, 2012)

357mag1 said:


> JD,
> I'm trying that test on my older one. I will leave the cap off for a while and see if it drops back to low mode.
> 
> It just takes money to get a new one!!!
> ...



357mag - i'm interested in that link...could you post it or send it to me in a 'pm'?...
i'm very new to this flashlight obsession thing but caught the bug and set my sights on the tk70...plan to purchase one within 2 weeks...was going to buy from battery junction...if i can get a new tk70 for better price i'm interested of course...

also, getting somewhat confused by all these posts here re-best rechargeable d cells...there are several different opinions by different postees on this thread....i read some strongly stated opinion and thought i have the answer, only to see it shot down by another opinion...crap....

357mag, since you've evidently done a lot of long term d-cell tests AND own a couple of tk70s i'm willing to stake my choice on your recommendation man....
along with the tk70, i'm planning to buy the maha c808m charger so i can charge d cells for the tk70 AND use 4 d cell batteries in that light, not alternative adapters, etc...length and weight penalty notwithstanding.....which 'top 2' nimh lsd rechargeable d-cells are recommended after all, considering the longest run time on turbo mode and extended period of being inside the flashlight [i.e. slow discharge]??...
thanks - jerzy...


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## 357mag1 (Feb 18, 2012)

I've been gone over four hours now with the Older TK70 tailcap off. I just put it on and it started up in the Hi mode which is where I left it. I'm not sure why yours resets JD.


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## 357mag1 (Feb 18, 2012)

LIGAF said:


> 357mag - i'm interested in that link...could you post it or send it to me in a 'pm'?...
> i'm very new to this flashlight obsession thing but caught the bug and set my sights on the tk70...plan to purchase one within 2 weeks...was going to buy from battery junction...if i can get a new tk70 for better price i'm interested of course...
> 
> also, getting somewhat confused by all these posts here re-best rechargeable d cells...there are several different opinions by different postees on this thread....i read some strongly stated opinion and thought i have the answer, only to see it shot down by another opinion...crap....
> ...



I don't claim to be an expert and can only comment on the cells I've tested. For LSD I've tested the AccuEvolution, Imedion and Tenergy Centura. Though one of the most economical the Centura easily best the other two. 

If it were me I would not purchase LSD D cells unless I planned to put them into a light and let it set for at least 6 months and that light had to work when I picked it up!!! 

Otherwise the best Nimh D cell on the market that I've tested is the Tenergy Premium. I would purchase them from All-battery.com but use their Ebay store. The batteries are listed cheaper there and shipping is less.

The Premiums I've tested after setting for 2 months still have more capacity left than the best LSD cells do fresh off the charger. The fact the Premiums still maintain a higher voltage under load even though their resting voltage is lower makes them the hands down winner for me.

Battery Junction would not be on my list of Merchants to buy anything from ever again.

Check your PMs.


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## SilverFox (Feb 18, 2012)

Hello CyberCT,





CyberCT said:


> 357mag1, I appreciate your feedback and help.
> 
> I'm learning, and think I finally have an idea of what's going on here. Confirm I do or correct me where I don't. I'm still learning and have picked up bits & pieces over the last two years but think I got it:
> 
> ...




A slight correction... Or perhaps a perspective review.

The mAh of a cell refers to its capacity. This capacity is determined during discharge. The discharge capacity is the "official" number. This number is dependent upon a number of things including the discharge rate. When a cell is labeled with a capacity, it was supposed to have been tested according to standard methods that include a standard charge followed by a standard discharge.

In battery testing a standard charge involves charging the cell at a 0.1C charge rate for 16 hours. Following a rest period the cell is then subjected to a standard discharge. The standard discharge rate is 0.2C. This works out to 16 hours of charging, about 1 - 2 hours of rest, and about 5 hours of discharge.

While battery manufacturers test according to these standards, there is no rule that the person making up the label for the cell has to read the results, and there is varying "truth in labeling."

This is why we do testing. If the label says 10000 mAh, and the cell only is capable of delivering 6000 mAh, we know that the label was optimistic. Some manufacturers (Sanyo Eneloop for example) give a minimum capacity for their cells. In this particular case, the Eneloop cells actually test out very close to what they are labeled at.

The amount of charge you put into the cell is important, but it tells you nothing about the capacity of the cell. It does tell you how well the termination method used by the charger works. For example, the amount of charge that goes into a cell depends upon charge rate. When charging at 0.1C, if everything were perfect the cell should be fully charged in 10 hours. However, due to inefficiencies a full charge actually takes 16 hours. If you raise the charge rate to 1.0C, you expect the total charge going into the cell to be about 105 - 110%. If your charger misses its termination, the cell gets hot and the charge number raises much higher. This can actually damage the cell and produce a lower discharge capacity.

So, if you see a cell that has a higher charging capacity it could mean that something is going on with either the charger or the cell and it has been overcharged due to the charge termination signal being missed.

You have a good grasp on the discharge capacity. This is the actual capacity of the cell. The standard load used to determine the capacity is a 5 hour discharge or 0.2C. I like to see how close the labeled capacity is to the cells actual capacity, and then to see what the capacity of the cell is under the loads I plan to use.

The voltage under load varies with the load. The "nominal" voltage of 1.2 volts comes from the voltage seen during the standard discharge. As a cell ages, its ability to hold voltage under load is reduced. This reduced voltage also results in reduced capacity. When using cells in a multi cell application you are better off if the cells are matched to each other. Matching is done on both capacity and voltage under load. Matched cells help reduce the problem of cell reversal when the battery pack is at the end of the discharge cycle.

It is rare to have a cell match its labeled capacity. The exception to this is if the cell has a discharge sheet from the battery manufacturer. For example with AA cells the sheet from Sanyo on the Eneloop cells very closely matches the labeled capacity of the cell. GP cells are a little off on labeling, but the sheets are closer to the actual capacity. The GP 2700 mAh cells while having 2700 mAh on their label have data sheets that show the capacity is closer to 2550 mAh. When you test these cells you find that they come in close to the data sheet capacities. The label in this case is optimistic.

Capacity under load is a good way to start looking at the quality of a cell, but the story goes on from there. Voltage under load is another consideration, as are the number of charge/discharge cycles the cell can handle. I have had some cells that had good capacity and good voltage under load, but they only lasted 20 cycles and then everything tanked and they turned into crap cells. Other cells with less capacity were still going strong after 100 charge/discharge cycles, and in my opinion they were higher quality.

This should help you understand a little more about battery testing and how to interpret the numbers you observe.

Tom


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## LIGAF (Feb 18, 2012)

357mag1 said:


> I don't claim to be an expert and can only comment on the cells I've tested. For LSD I've tested the AccuEvolution, Imedion and Tenergy Centura. Though one of the most economical the Centura easily best the other two.
> 
> If it were me I would not purchase LSD D cells unless I planned to put them into a light and let it set for at least 6 months and that light had to work when I picked it up!!!
> 
> ...



got it, thank you...
};->


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## CyberCT (Feb 18, 2012)

Well my TK70 did not arrive today either, so I said screw it and put my first half of Tenergy cells in the "soft" "conditioning" mode of my 808M. If it takes 60 hours to complete, they should be ready Monday night. My TK70 should be at my doorstep earlier that night when I get home so it's no big deal. I'm going to do some runtime tests to turbo with the 3 cell tube, and the 4 cell tube. Seeing how these batteries are hit or miss, I'll to the same test once I have rigged up my C9000 to discharge my D cells and give an mah value, and then do cell matching. I'm thinking of doing 3 tests per cell and I'll take the average. I have found from testing my AA and AAA batteries that sometimes all 4 bays have a lower reading, and the next time they have a higher reading from the same cells, same cycling mode. Not too much of a difference but an average is the best way to go I think.


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## CyberCT (Feb 19, 2012)

I put my 2 best Eneloops and 2 best Imedions on the discharge cycle at 1 amp. I used only the 1st bay for all 4. So I ran the C9000 four times. Here are the results at 1 amp disharge:


Imedion 1: 2253 mah, 1.15v
Imedion 2: 2214 mah, 1.15v
Eneloop 1: 1894 mah, 1.14v
Eneloop 2: 1879 mah, 1.22v

SO is the C9000 showing the voltage of the cells when the discharge stopped? Or how they held up?


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## 357mag1 (Feb 19, 2012)

CyberCT said:


> I put my 2 best Eneloops and 2 best Imedions on the discharge cycle at 1 amp. I used only the 1st bay for all 4. So I ran the C9000 four times. Here are the results at 1 amp disharge:
> 
> 
> Imedion 1: 2253 mah, 1.15v
> ...



Unfortunately the C9000 doesn't not show average voltage for the discharge cycle. You are just seeing the resting voltage at that moment after discharge. Depending on how long you wait it will continue to climb until it stops around the 1.2 volt mark.

Try discharging them at the same time push the "Slot" button at different times during the discharge cycle (5 minutes, 10, 20, 30, 45, ect). Each slot will rotate through the voltage of the cell, it takes about 10 seconds for each slot. Write those numbers down and compare them. You will have a fair idea which batteries maintain the higher voltage.

My Triton2 EQ provides the average voltage during discharge something I wish the C9000 did.


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## 357mag1 (Feb 19, 2012)

My low capacity Blue Tenergy D cell completed the "Conditioning" cycle on the MAHA 808. I let it rest an hour and it read the lowest capacity yet, 5862mah when discharged at 3 amps. Previously it has read between 5899 and 5929mah. 

I was going to call it a weak cell but it is really just lower in capacity as it maitains voltage under load with the best cells. I wish I had annotated which cells were the lowest coming out of the pack. I'm wondering if they are the lower capacity cells.


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## sadtimes (Feb 19, 2012)

357mag1 did you get my pm?


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## 357mag1 (Feb 20, 2012)

drmalenko said:


> 357mag1 did you get my pm?



Just got it. I didn't notice PMs piling up in my inbox. Thanks for the heads up.


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## CyberCT (Feb 20, 2012)

357mag1 said:


> CyberCT,
> 
> Current in series is common so whatever current is at the tailcap all cells are felling that draw. In the case of the TK70 all three cells are feeling the 9.84amp draw (from my test). With 4 cells it drops to 6.25amps and again each cell has that current drawn through it.
> 
> My Newer TK70 draws 10.7amps on 3 cells and 7.2amps with 4 cells.



You know, I'm thinking about the LION option. If the TK70 steps down from turbo to high when only 3.8v is available from the batteries, wouldn't a LION step down too soon? If you charge 2 LION 32600 cells to say 4.2v and then use them in the TK70 the TK70 would step down when the LIONs are only what, 70% capacity remaining? Because LION cells are rated at 3.7v.


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## CyberCT (Feb 20, 2012)

Did a runtime test of 4 of 8 Tenergys fresh off "soft" "condition" mode from my Maha 808S charger. 1 hour 2 minutes till the light stepped down from turbo to high. You can hear the driver in the light at the end squealing. It sounded like a dive bomb and then went silent haha.

Of the other 4 that were finishing the "soft" "conditioning" mode, 1 battery ended with the other 4 that went into the TK70, but 3 just kept on taking charge from the charger, blinking with the 3 capacitiy indicators on full. After over an hour and a half of continuous blinking, after the last of the other 5 batteries finished, I just took them off the charger. Is that OK? My assumption was that these 3 are crap cells and the charger is having a difficult time distinguishing their final capacity which is why the charger keeps trying to feed them charge till done.

I tested the TK70 in the tub in cool water. The head and heatsink were just a tad warm even under the cool water at 1 hour 2 minutes. But not hot at all.


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## 357mag1 (Feb 20, 2012)

CyberCT said:


> You know, I'm thinking about the LION option. If the TK70 steps down from turbo to high when only 3.8v is available from the batteries, wouldn't a LION step down too soon? If you charge 2 LION 32600 cells to say 4.2v and then use them in the TK70 the TK70 would step down when the LIONs are only what, 70% capacity remaining? Because LION cells are rated at 3.7v.



Voltage in series is additive. Lithiums shouldn't be drained below 3v so even drained they would still have 6v not counting for voltage sag.


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## 357mag1 (Feb 20, 2012)

CyberCT said:


> Did a runtime test of 4 of 8 Tenergys fresh off "soft" "condition" mode from my Maha 808S charger. 1 hour 2 minutes till the light stepped down from turbo to high. You can hear the driver in the light at the end squealing. It sounded like a dive bomb and then went silent haha.
> 
> Of the other 4 that were finishing the "soft" "conditioning" mode, 1 battery ended with the other 4 that went into the TK70, but 3 just kept on taking charge from the charger, blinking with the 3 capacitiy indicators on full. After over an hour and a half of continuous blinking, after the last of the other 5 batteries finished, I just took them off the charger. Is that OK? My assumption was that these 3 are crap cells and the charger is having a difficult time distinguishing their final capacity which is why the charger keeps trying to feed them charge till done.
> 
> I tested the TK70 in the tub in cool water. The head and heatsink were just a tad warm even under the cool water at 1 hour 2 minutes. But not hot at all.



Actually they were probably your better quality cells as far as capacity is concerned. The first one off conditioning on my Maha 808 is the cell that tested lowest in capacity. The cells that could go over 8000mah took much longer. The reason for this is they take longer to charge and discharge. So contrary to what you thought those are probably your highest capacity cells.


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## CyberCT (Feb 20, 2012)

357mag1, please help me understand. So two LION cells at full charge each are 4.2v x 2 = 8.4v. So nominal LION cell voltage is 3.7v x 2 = 7.4v. If each cell was discharged to 3v each (the safe minimum), that's 3v x 2 = 6v. With no battery protection, the TK70 driver would not step down from turbo to high until just 3.8v was available. So it would drain the LION cells down to 1.9v each x 2 = 3.8v.


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## 357mag1 (Feb 20, 2012)

CyberCT said:


> 357mag1, please help me understand. So two LION cells at full charge each are 4.2v x 2 = 8.4v. So nominal LION cell voltage is 3.7v x 2 = 7.4v. If each cell was discharged to 3v each (the safe minimum), that's 3v x 2 = 6v. With no battery protection, the TK70 driver would not step down from turbo to high until just 3.8v was available. So it would drain the LION cells down to 1.9v each x 2 = 3.8v.



You are correct, if the batteries are not protected it would drain them too low. Once you do that a Lithium cell is questionable at best and can be quite dangerous. In this respect Nimh chemistry is much safer and more rugged.


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## CyberCT (Feb 20, 2012)

357mag1 said:


> Actually they were probably your better quality cells as far as capacity is concerned. The first one off conditioning on my Maha 808 is the cell that tested lowest in capacity. The cells that could go over 8000mah took much longer. The reason for this is they take longer to charge and discharge. So contrary to what you thought those are probably your highest capacity cells.



I think you are correct. That second batch of batteries, the 3 that I took off the charger charging 1.5 hours longer, 1 that finished previously with the rest, lasted 1 hour 10 minutes on turbo in my light. That's pretty darn good! I thought I read somewhere that the TK50 battery tube fits on the TK70 tube. I'll have to confirm it but if so and I can find a distributor that sells the tube only then I'll spring for it. If I can get more runtime with the light and with less squealing at the end of turbo mode (which would scare the fish away maybe?) then I think that's ideal.


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## 357mag1 (Feb 21, 2012)

CyberCT said:


> I think you are correct. That second batch of batteries, the 3 that I took off the charger charging 1.5 hours longer, 1 that finished previously with the rest, lasted 1 hour 10 minutes on turbo in my light. That's pretty darn good! I thought I read somewhere that the TK50 battery tube fits on the TK70 tube. I'll have to confirm it but if so and I can find a distributor that sells the tube only then I'll spring for it. If I can get more runtime with the light and with less squealing at the end of turbo mode (which would scare the fish away maybe?) then I think that's ideal.



The AccuEvolution cells which test out between 8500 -8900mah struggle to reach 60 minutes. That higher voltage under load makes a difference, the TK70 on Turbo draws over 1amp more from the AccuEvolution cells due to voltage sag which depletes the cell quicker.

I just tried it and the TK50 battery tube fits. I added the spacer and used 3 D cells to make sure it made proper electrical contact and it does. The TK70 spacer doesn't seat into the TK50 tube deep enough for the O-ring to seal. This applies to the TK70 tailcap as well. The O-ring is still exposed when it is screwed down tight on the TK50 tube. You would need a TK50 tailcap as well or someone to modify the TK70 cap length to fit. Problem is once modified the TK70 tailcap wouldn't make contact on the TK70 tubes.

I'm assuming you intend to use Lithium-Ion cells. Remember two of them are about .8inches longer than two Nimh D cells. You have about an inch of spring to work with in the TK50 tailcap so it could be done. It would be an unbalanced light though, very head heavy and tend to want to tip toward the head unless you placed your hand around the switches.

Not trying to dampen your enthusiasm just bringing to light any potential issues I can foresee.  You might as well buy the TK50 outright, it is a great little light.


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## hank (Feb 21, 2012)

On conditioning -- I have a Maha C9000 (the AA-size charger).
It has a 2.0A power supply.

I can extend the contacts with clips and wires and magnets to handle these Tenergy D cells.

How do I set it up to condition/break in these cells -- how many can it handle at what charge/discharge settings?


----------



## hank (Feb 21, 2012)

On conditioning -- I have a Maha C9000 (the AA-size charger).
It has a 2.0A power supply.

I can extend the contacts with clips and wires and magnets to handle these Tenergy D cells.

How do I set it up to condition/break in these cells -- how many can it handle at what charge/discharge settings?


----------



## CyberCT (Feb 21, 2012)

357mag1 said:


> The AccuEvolution cells which test out between 8500 -8900mah struggle to reach 60 minutes. That higher voltage under load makes a difference, the TK70 on Turbo draws over 1amp more from the AccuEvolution cells due to voltage sag which depletes the cell quicker.
> 
> I just tried it and the TK50 battery tube fits. I added the spacer and used 3 D cells to make sure it made proper electrical contact and it does. The TK70 spacer doesn't seat into the TK50 tube deep enough for the O-ring to seal. This applies to the TK70 tailcap as well. The O-ring is still exposed when it is screwed down tight on the TK50 tube. You would need a TK50 tailcap as well or someone to modify the TK70 cap length to fit. Problem is once modified the TK70 tailcap wouldn't make contact on the TK70 tubes.
> 
> ...



Hmm I need the waterproofness and that's too much modding so I'll stick with the stock tubes. I have a bunch of those 2AA to D cell adapters which have plastic bodies. I would simply cut one in half and then cut it down further, solder 16 gauge copper wire on the inside, and electrical tape it shut. That way I shouldn't have to cut the tailspring and have a perfect "dummy" cell.

I would put the dummy cell as the 1st cell in the 3D tube, so the weight of the LION batteries would be on the handle end helping to balance out the light a bit. My problem is how the heck to LION cells even work then with this light? Unprotected cells will be overdischarged so they don't work. The Novae which are the only protected LION 32650 cells I know of tha tare supposd to be quality, don't work either because their protection circuit kicks in. So what LION cells do I use??


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## CyberCT (Feb 21, 2012)

hank said:


> On conditioning -- I have a Maha C9000 (the AA-size charger).
> It has a 2.0A power supply.
> 
> I can extend the contacts with clips and wires and magnets to handle these Tenergy D cells.
> ...



Although they have not arrived in the mail yet, I bought a set of those AAA to AA adapters. I bought a wooden dowel at Home Depot for $1. I will solder 20 gage solid copper wire (plastic sheath like all wire, but the copper is not braided) to the inside postiive and negative ends of the AAA AA adapters. Then I will cut the wooden dowel down to the size of an AAA battery and put it in the adapters to keep tension on soldered ends from being yanked out. I also bought those 2D cell series adapters in Radioshack for $2 each. I will wire them up as individual cells to each AAA AA adapter to put in the C9000.


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## hank (Feb 21, 2012)

Sounds good; I was thinking of using alligator clips but the plastic-adapter-and-dowel sounds like a better electrical contact.
I'll get the same stuff and follow along behind. Do you have a notion if you can condition more than one of these D cells at a time, given the 2.0A power supply?


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## 357mag1 (Feb 21, 2012)

CyberCT said:


> Although they have not arrived in the mail yet, I bought a set of those AAA to AA adapters. I bought a wooden dowel at Home Depot for $1. I will solder 20 gage solid copper wire (plastic sheath like all wire, but the copper is not braided) to the inside postiive and negative ends of the AAA AA adapters. Then I will cut the wooden dowel down to the size of an AAA battery and put it in the adapters to keep tension on soldered ends from being yanked out. I also bought those 2D cell series adapters in Radioshack for $2 each. I will wire them up as individual cells to each AAA AA adapter to put in the C9000.



For a spacer I've used copper pipe with a cap on the end the spring pushes on. You could cap both ends I just let the pipe push against the negative end of the battery. Then I used PVC pipe for a sleeve and the copper pipe fit inside of it. You could use aluminum rod and just wrap it with tape to take up the slack inside the PVC pipe.

When performing the test for you on the TK70 I just used a bolt inside PVC with a coin shaped rare earth magnet to get the proper spacing. It wasn't fancy but is solid and quick.

I just tried a runtime with the Novae batteries and the light went dead at 4min 12sec so they difinitely wouldn't do you any good.


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## CyberCT (Feb 21, 2012)

hank said:


> Sounds good; I was thinking of using alligator clips but the plastic-adapter-and-dowel sounds like a better electrical contact.
> I'll get the same stuff and follow along behind. Do you have a notion if you can condition more than one of these D cells at a time, given the 2.0A power supply?



My only plan for using the C9000 with my D cells was to do a discharge at 1 amp per cell. 1 amp is the max discharge rate the C9000 will allow. Since I'm essentially discharging batteries wouldn't that use very little power from the outlet? I didn't know the power supply draws a max of 2amps from the outlet. That doesn't make sense though because if you just charge four AA batteries at 1 amp each, that's 4 amps.


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## 357mag1 (Feb 21, 2012)

CyberCT said:


> My only plan for using the C9000 with my D cells was to do a discharge at 1 amp per cell. 1 amp is the max discharge rate the C9000 will allow. Since I'm essentially discharging batteries wouldn't that use very little power from the outlet? I didn't know the power supply draws a max of 2amps from the outlet. That doesn't make sense though because if you just charge four AA batteries at 1 amp each, that's 4 amps.



The C9000 can actually put out 2amps to all 4 cells for a total of 8amps. Multiply 8x1.5volts and you achieve power in watts. In this case 12watts consumed to provide 2amps to all 4 cells. The power supply (wall unit) for the C9000 provides 12v x 2amps for a total of 24watts. Since nothing is perfect the unit may draw 15-16 watts from the wall to power all 4 channels at 2amps.

You are correct that during discharge very little is needed from the power supply. The main limitation is getting rid of the heat as that power from the cell has to go somewhere.


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## Sagebrush (Feb 21, 2012)

drmalenko said:


> This is a super deal and super hard to pass up.. he has 81 of them left (show 81 sets of 8)... He also has another auction with 4 for 15.00 in case you dont need 8
> 
> Also posting in the good deals section
> 
> ...



I've done OK with those blue ones from that vendor. Out of the plastic they are really low at .87 to .94, mine have charged up so far. I'm putting them in my lanterns, mag lites and my tent fan. It sure helps the wallet at half the price of my Tenergy Premiums. :thumbsup:


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## CyberCT (Feb 22, 2012)

Sagebrush said:


> I've done OK with those blue ones from that vendor. Out of the plastic they are really low at .87 to .94, mine have charged up so far. I'm putting them in my lanterns, mag lites and my tent fan. It sure helps the wallet at half the price of my Tenergy Premiums. :thumbsup:



Yea I figure for $50 for 16 cells it's not too bad, even if there are crappy performers there. I have two XML modified Rayovac Sportsman Xtreme lanterns, each takes 3 D cells. So that's 6 of 16. So even if my worst D cells are 7,000 mah that's still enough runtime on high for the whole night. Then I'd save my best performing Tenergys for the TK70 if I were to use it. Which is 4 of 16. What tent fan do you have? I have seen them and was thinking about buying a small but good D cell one, powered by at most 6 D cells which is what I have remaining.


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## JudasD (Feb 22, 2012)

I am having a bit of an issue with the Tenergy Blue D Cells from that ebay seller. My cells also arrived with a very low voltage. all were in the .9 range. When i charge them via the Maha 9000 the cells will never get to 1.47 volts for them to terminate. The voltage just stays at 1.41 and never goes up. I put 12,000mAh into them and it never went past 1.41 volts. They also never got hot.
After the Maha, i i put the cells on my hobby charger and they terminate right away when the peak delta is set to 5mV. They only discharge to about 7,000mAh.  I'll try to exercise them and see if they open up. Anyone else seen this?

Thanks,
JD


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## Sagebrush (Feb 22, 2012)

I use a 4 d fan from academy. I thinks its a timber creek . It will go two nights . Its the yellow and black one with the led lights.

My blue tenergies shut off at 1.40 using the tenergy charger. Same with the premium ones . Its probably the 7.5 hour timer.

Sent from my GT-S5690L using Tapatalk


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## CyberCT (Feb 22, 2012)

JudasD said:


> I am having a bit of an issue with the Tenergy Blue D Cells from that ebay seller. My cells also arrived with a very low voltage. all were in the .9 range. When i charge them via the Maha 9000 the cells will never get to 1.47 volts for them to terminate. The voltage just stays at 1.41 and never goes up. I put 12,000mAh into them and it never went past 1.41 volts. They also never got hot.
> After the Maha, i i put the cells on my hobby charger and they terminate right away when the peak delta is set to 5mV. They only discharge to about 7,000mAh.  I'll try to exercise them and see if they open up. Anyone else seen this?
> 
> Thanks,
> JD



How did you charge them on the Maha C9000? My initial plan was just a discharge per cell at 1 amp on the C9000 to get the capacity per cell. Charging them is done on my Maha 808D. Also, I used a volt meter for each cell off my 808D and none of them were 1.5v. They were in the 1.4v range. But that's normal, my eneloops come off in the 1.4v range too.


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## Sagebrush (Feb 22, 2012)

CyberCT said:


> How did you charge them on the Maha C9000? My initial plan was just a discharge per cell at 1 amp on the C9000 to get the capacity per cell. Charging them is done on my Maha 808D. Also, I used a volt meter for each cell off my 808D and none of them were 1.5v. They were in the 1.4v range. But that's normal, my eneloops come off in the 1.4v range too.



I don't have any fancy chargers and my D cells just came off the V-9688 at 1.42 to 1.40. After three hours they are reading 1.35. Thats the first charge on new blue D cells. This batch of 4 were all .88 out of the box.

I didn't know that they could reach 1.5? My Premiums stay 1.35 to 1.38 after sitting a day or so. Is that right?


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## JudasD (Feb 22, 2012)

CyberCT said:


> How did you charge them on the Maha C9000? My initial plan was just a discharge per cell at 1 amp on the C9000 to get the capacity per cell. Charging them is done on my Maha 808D. Also, I used a volt meter for each cell off my 808D and none of them were 1.5v. They were in the 1.4v range. But that's normal, my eneloops come off in the 1.4v range too.



I just have dummy cells that have wire outputs that then go from the maha 900 to a cradle for my cells. I charged them at 2A. The maha 9000 terminates at 1.47v. This is the voltage that is read DURING charge. I have Tenergy Premium and Centura D that will both terminate at 1.47 on the maha. Right after charge they will read high 1.3x or low 1.4x. These blue Tenergy will just sit at 1.41 and keep taking charge current. they never got hotter and the volts never go any higher. They must have a very high internal resistance. Maybe from sitting on the shelf for a very long time in a discharged state?

JD


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## Russel (Feb 22, 2012)

JudasD said:


> I just have dummy cells that have wire outputs that then go from the maha 900 to a cradle for my cells. I charged them at 2A. The maha 9000 terminates at 1.47v. [...]



Remember that unless you have one of the older MH-C9000 chargers, there is a limit of about 4500mAh (if I remember the number correctly) in every [edit] Charge [end edit] mode except break-in. Break-in mode has a limit of 20000mAh, if I remember correctly. Of course, you can always run a second charge cycle to completely charge 5000mAh to 10000mAh D cells.


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## JudasD (Feb 22, 2012)

Russel said:


> Remember that unless you have one of the older MH-C9000 chargers, there is a limit of about 4500mAh (if I remember the number correctly) in every mode except break-in. Break-in mode has a limit of 20000mAh, if I remember correctly. Of course, you can always run a second charge cycle to completely charge 5000mAh to 10000mAh D cells.



Yes, i have one of the newer ones. I have to run multiple charge cycles back-to-back. So far i have run 3 cycles and it will never terminate and just stays at 1.41 volts. On my Tenergy D Premiums, which are also 10,000mAh, the charger usually terminates in the middle-ish of the 3rd cycle when it hits 1.47 volts.

JD


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## CyberCT (Feb 23, 2012)

Russel said:


> Remember that unless you have one of the older MH-C9000 chargers, there is a limit of about 4500mAh (if I remember the number correctly) in every mode except break-in. Break-in mode has a limit of 20000mAh, if I remember correctly. Of course, you can always run a second charge cycle to completely charge 5000mAh to 10000mAh D cells.



Wait, so the C9000 will not discharge my blue Tenergy D cells completely, if I do a discahrge mode? My initial intention was to do a discharge at 1 amp for all my Tenergys and see their capacity. I don't want to run 2 discharge mode cycles.


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## JudasD (Feb 23, 2012)

CyberCT said:


> Wait, so the C9000 will not discharge my blue Tenergy D cells completely, if I do a discahrge mode? My initial intention was to do a discharge at 1 amp for all my Tenergys and see their capacity. I don't want to run 2 discharge mode cycles.



It will discharge them completely. It is the charge cycle that is limited to 4,000mAh per channel. So you will have to do back-to-back charge cycles until the charger terminates on its own.

JD


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## sadtimes (Feb 23, 2012)

Sagebrush said:


> I've done OK with those blue ones from that vendor. Out of the plastic they are really low at .87 to .94, mine have charged up so far. I'm putting them in my lanterns, mag lites and my tent fan. It sure helps the wallet at half the price of my Tenergy Premiums. :thumbsup:



All of mine had similar voltage out the plastic. I charged them, then discharged, then charged again. They all seem fine and perform just fine. 

I have several mag lights that I have custom SST-90 builds in and these cells deliver over 10 amps with no trouble...


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## 357mag1 (Feb 23, 2012)

CyberCT said:


> Wait, so the C9000 will not discharge my blue Tenergy D cells completely, if I do a discahrge mode? My initial intention was to do a discharge at 1 amp for all my Tenergys and see their capacity. I don't want to run 2 discharge mode cycles.



I discharged three of my cells at 1amp to help give you a comparison. Even though there seemed to be no difference doing it at 3amps or 5amps when done at 1amp capacity showed between 600-650ma higher.

My low capacity cell that was averaging right around 5900mah gave 6506mah. By subtracting 600mah you should have a pretty valid idea of capacity per cell at the load your TK70 pulls.


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## CyberCT (Feb 23, 2012)

357mag1 said:


> I discharged three of my cells at 1amp to help give you a comparison. Even though there seemed to be no difference doing it at 3amps or 5amps when done at 1amp capacity showed between 600-650ma higher.
> 
> My low capacity cell that was averaging right around 5900mah gave 6506mah. By subtracting 600mah you should have a pretty valid idea of capacity per cell at the load your TK70 pulls.



Thanks for the heads up. I'll keep that in mind when I use my C9000 to do the discharge test for my Tenergys.


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## CyberCT (Feb 24, 2012)

I went downstairs and checked my 808M charger before work. It's been running a "soft" "conditioning" cycle for over 2 days on my second batch of 8 Tenergy blue D cells. I noticed that the "condition" indicator was no longer present on the readout, but "soft" was there. I know both were on the indicator previously. I don't remember what was on the display after the first batch of 8 D cells went through the "soft" "conditioning" mode but is it normal for "condition" disappear from the indicator toward the end of the whole cycle?


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## Danielight (Feb 24, 2012)

357mag1 said:


> Avoid the AccuEvolution D cells at all cost. The old cells were great, the cells they presently sell are the worst D rechargeable cells I have tested and I've tested a bunch.
> 
> The Imedion D cells are not much better.
> 
> ...


Hmmmm ... you mean like the Titanium D12000 rechargeables available thru Battery Junction? I bought several of those thinking I might need them for my big MagLight, but they have been sitting in a charger ... haven't used them yet!


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## 357mag1 (Feb 24, 2012)

Danielight said:


> Hmmmm ... you mean like the Titanium D12000 rechargeables available thru Battery Junction? I bought several of those thinking I might need them for my big MagLight, but they have been sitting in a charger ... haven't used them yet!



Yes, if they are anything like the Titanium C cells they won't meet there capacity and sag terribly under load. Not unusable but there are much better choices on the market. Until somebody comes out with something better than the Tenergy Premium D cells they are my choice.


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## 357mag1 (Feb 24, 2012)

CyberCT said:


> I went downstairs and checked my 808M charger before work. It's been running a "soft" "conditioning" cycle for over 2 days on my second batch of 8 Tenergy blue D cells. I noticed that the "condition" indicator was no longer present on the readout, but "soft" was there. I know both were on the indicator previously. I don't remember what was on the display after the first batch of 8 D cells went through the "soft" "conditioning" mode but is it normal for "condition" disappear from the indicator toward the end of the whole cycle?



I'm pretty sure the word "conditioning" stayed on mine the whole time but can't swear to it. My cells took about three days to complete.


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## jayflash (Feb 24, 2012)

When running lengthy tests, conditioning, and recharging, the chance of very brief power outages, sags, surges or spikes may fool the charger and reset it. I'll have to re-read the owner's manual about the missing "conditioning" indicator, but I remember mine did that at least once.

Now I use a spike protected UPS to supply my chargers and, so far, haven't had previous problems.


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## CyberCT (Feb 24, 2012)

It took 2.5 days to complete the whole cycle. I have a 350watt hour battery that is connected to my charger, and the battery is also connected to the wall outlet. So in a way it acts like a UPS. I ran all my chargers off of it and the first conditioning cycle as well on the 808M.

I checked the owners manual too but in those 2 pages, there's no mention of this issue. I emailed Powererex this morning.


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## jayflash (Feb 24, 2012)

Is that about the size of three "typical" 12v SLA batteries or garden tractor size? That's big enough for any normally short AC outage. May I assume the battery charger and 808 are attached in parallel with the battery? The battery should act as a large capacitor to help limit spikes, but maybe some AC aberration got through.


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## CyberCT (Feb 24, 2012)

jayflash said:


> Is that about the size of three "typical" 12v SLA batteries or garden tractor size? That's big enough for any normally short AC outage. May I assume the battery charger and 808 are attached in parallel with the battery? The battery should act as a large capacitor to help limit spikes, but maybe some AC aberration got through.



No. My 350w hour battery is acting as the power source. Here is what I have:
http://www.goalzero.com/shop/p/64/Extreme-350-Adventure-Kit/1:3/

The specs of the battery are on the middle of the page. The battery is plugged into the wall outlet at all times while charging my D cells, so the wall outlet keeps supplying power to the battery, acting like a UPS.


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## Russel (Feb 24, 2012)

CyberCT said:


> It took 2.5 days to complete the whole cycle. I have a 350watt hour battery that is connected to my charger, and the battery is also connected to the wall outlet. So in a way it acts like a UPS. I ran all my chargers off of it and the first conditioning cycle as well on the 808M.
> 
> I checked the owners manual too but in those 2 pages, there's no mention of this issue. I emailed Powererex this morning.



Are you using an inverter between the battery and the MH-C808M charger?

Oops! You answered my question in your next post...


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## Danielight (Feb 24, 2012)

ΓΕΝΗΘΗΤΩ ΦΩΣ ... "Let there be light" (Genesis 1:3, LXX).


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## CyberCT (Feb 24, 2012)

I rigged up my plastic / wood dummy cells and Radioshak D battery holders. It's complete, although looks kinda crappy lol. So now I have 4 of my D Tenergy cells discharging at 1 amp on my C9000. 2 bays show discharge 1010 mah, one 999 mah and last one 1003 mah. Why the difference between bays?


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## 357mag1 (Feb 24, 2012)

CyberCT said:


> I rigged up my plastic / wood dummy cells and Radioshak D battery holders. It's comple, although looks kinda crappy lol. So now I have 4 of my D Tenergy cells discharging at 1 amp on my C9000. 2 bays show discharge 1010 mah, one 999 mah and last one 103 mah. Why the difference?



You might want to see if the connection didn't get disturbed and the 103mah is actually charging. If the connection was lost then picked up again it would start charging.


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## CyberCT (Feb 25, 2012)

I fixed a few typos in my previous post. I ended up accidently bumping the C9000 and it reset so I stopped it. I'm going to run 2 "soft" "condition" cycles on my Tenergys and after an hour rest put them in the C9000 and do a discahrge test to get the capacity. Although somehow the 808M lost the conditioning cycle on one and one of the cells slipped out just enough to not be read on the 2nd "soft" "conditioning" cycle I just started. I simply just pushed it a tad back in.


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## CyberCT (Feb 27, 2012)

I have a few of the Maha MH-C800S chargers (8 AA) and didn't realize it but you can do a "soft" "condition" mode together on those chargers as well. So I did one cycle per charger on my Imedions and I have found that for both chargers, the word "soft" was on the LCD screen but "condition" was not. This is near the end of the cycle, when the batteries were charging with 2/3 or 3/3 battery life bars blinking. And my next "soft" "condition" mode is complete on the 808M and only "soft" was on the screen when it ended. SO this must be normal.

Now a question about the Tenergys. Right off the "soft" "condition" mode from the 808M I put them into my rig to have the C9000 discharge them at 1 amp. Before I get into that, I did a test with an AA eneloop in a D cell adapter. At first bays 1 thru 4 read the following when doing the discharge cycle: 1010mah, 999mah, 1010mah, 1002 mah. I don't know why bays 1 and 3 are together and 2 and 4 are together for discharge rates. I swapped the battery adapters in the different slots and started another disharge test on the Eneloops and the bays read the same, so it's not my rig specifically. It has been an hour now and the Tenergy in the 2nd bay is now "done" and I was watching it, the voltage dropped to 0.92v and when I came back in about 5 minutes the battery was done. Strange, could the battery really be crap? Could it be my rig somehow and resistance? The rest seem to be discharging ok so far. The other 3 batteries are reading at 1.17v or so.

EDIT: The other 3 Tenergys were complete when I checked them before work. Their mah ranges were between 7800 mah and 7200 mah. Kinda crappy. I'll have to test that dud battery again on a different slot and heck a different adapter too on my C9000 D conversion setup. I have a feeling it's a dud but need to be sure.


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## hjjaleon (Feb 28, 2012)

I glad to know tenergy which I prepare to purchase is good. Thank all of you!


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## CyberCT (Feb 28, 2012)

Second batch of Tenergys off the C9000 range from 7500 to 8000 mah. Discharge is at 1 amp.


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## CyberCT (Mar 2, 2012)

What the heck? That one dud D cell, or so I thought, I charged again with the rest and did another discharge test. Now it shows a capacity of 8600 mah? I thought it was originally charged with the rest. Strange.


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## 357mag1 (Mar 2, 2012)

CyberCT said:


> What the heck? That one dud D cell, or so I thought, I charged again with the rest and did another discharge test. Now it shows a capacity of 8600 mah? I thought it was originally charged with the rest. Strange.



Not so strange really. On older Nimhs you definitely need to cycle them at least once to get an idea of actual capacity. One of my Blue Tenergy's only measured around 4000mah on the first discharge cycle at 3amps but the second cycle capacity jumped to 8000mah. I just bought another 8 of these cells because they are hard to beat at that price (just under $3.13 a piece shipped).


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## Quest4fire (Mar 6, 2012)

At present I have absolutely no specific use for these cells. Had to buy some though, great price! Mine were four for $15.00. Didn't see any other quantities for sale. Sorry if it's off topic, but has anyone tried out the blue Tenergy "C" cells?


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## JudasD (Mar 6, 2012)

I have cycled all 8 of my blue cells 3 times now using the Maha 9000 Breakin cycle. My best cell is only about 8,800 mAh. Not to impressive for a 10,000mAh battery if you ask me. I have a set of Tenergy Centura D (rated at 8,000mAh) and my WORST cell holds 8,500 mAh. Only 300mAh difference AND LSD properties. Not a difficult choice of which one to choose.

@Quest4Fire: i dont have the Blue Tenergy C cells, but i do have the white Premium Tenergy C cells. They are rated at 5,000mAh and my worst is getting 5,300mAh. They have a great discharge rate too! 

JD


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## AnAppleSnail (Mar 6, 2012)

357mag1 said:


> I just bought another 8 of these cells because they are hard to beat at that price (just under $3.13 a piece shipped).


 Where from?


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## Quest4fire (Mar 6, 2012)

> @Quest4Fire: i dont have the Blue Tenergy C cells, but i do have the white Premium Tenergy C cells. They are rated at 5,000mAh and my worst is getting 5,300mAh. They have a great discharge rate too!



Thanks JD!



> Where from?



See post # 39 by drmalenko


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## CyberCT (Mar 6, 2012)

357mag1 said:


> Not so strange really. On older Nimhs you definitely need to cycle them at least once to get an idea of actual capacity. One of my Blue Tenergy's only measured around 4000mah on the first discharge cycle at 3amps but the second cycle capacity jumped to 8000mah. I just bought another 8 of these cells because they are hard to beat at that price (just under $3.13 a piece shipped).



2 of my cells will just sit and keep charging on the charger forever until I disconnect it or take the battery out. That 8,600 mah on is one of them. Also to note, I ran another discharge cycle at 1 amp on that battery after charging it and letting it sit for a bit. The same thing happened initially where it went to crap after a half hour.



JudasD said:


> I have cycled all 8 of my blue cells 3 times now using the Maha 9000 Breakin cycle. My best cell is only about 8,800 mAh. Not to impressive for a 10,000mAh battery if you ask me. I have a set of Tenergy Centura D (rated at 8,000mAh) and my WORST cell holds 8,500 mAh. Only 300mAh difference AND LSD properties. Not a difficult choice of which one to choose.
> 
> @Quest4Fire: i dont have the Blue Tenergy C cells, but i do have the white Premium Tenergy C cells. They are rated at 5,000mAh and my worst is getting 5,300mAh. They have a great discharge rate too!
> 
> JD



I agree and kind of wish I went with the Tenergy LSD Centura cells although more expensive. How on earth did you do a full break-in cycle on your C9000? YOu can only set the max capacity to what? 3,000 mah or something lower than 8,000 mah?


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## JudasD (Mar 7, 2012)

CyberCT said:


> I agree and kind of wish I went with the Tenergy LSD Centura cells although more expensive. How on earth did you do a full break-in cycle on your C9000? YOu can only set the max capacity to what? 3,000 mah or something lower than 8,000 mah?



I am able to set the break-in cycle to 10,000 for the blue D cells on the C9000. I have read that it goes as high at 20,000, but i have not confirmed it.

JD


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## CyberCT (Mar 7, 2012)

Wow. I never tried it but thought I read previously that there was a limit way below 10,000. I would set the limit to 9,000 but it's worth a shot when I finish my 3rd round of discharge tests at 1 amp on the C9000.


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## JudasD (Mar 7, 2012)

CyberCT said:


> Wow. I never tried it but thought I read previously that there was a limit way below 10,000. I would set the limit to 9,000 but it's worth a shot when I finish my 3rd round of discharge tests at 1 amp on the C9000.



The C9000 will quite charging after 4,000mAh on every mode except for break-in. On Break-in it will supply the .1C (which is 1,000mAh for these D cells) for 16 hours. This charger would be pretty worthless to me if the break-in cycle needed restarting like the other charge modes. LOL

JD


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## CyberCT (Mar 8, 2012)

You're right. To my surprise you can go past 10,000 mah and the display says amp hours. I wonder why this is even available on this charger. Nothing over 3,000 is even possible with AA batteries. I have four Tenergys right now on the break-in mode. I put the capacity to 9,000 mah.

I took my Tenergy D blue label cells and put 3 in the 3D tube. Surprisingly the TK70 stayed on turbo for a total of 43 minutes, with the driver screaming the whole time. I'm surprised because I thought the TK70 would step down after a few minutes because of the huge load on the D cells for 9.5ish amps load per cell. The 3 Tenergys I used measured 7, 700 - 7,800 mah on the 1 amp discharge test of the Maha C9000 charger.


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## fireballtp (Mar 10, 2012)

I would like to persoanlly thank the OPs of this thread. I was able to get 16 Blue D Tenergys for use in my Mr Beams/Dorcy Porch lights. Even if these aren't the best batteries, they will still save a bundle over time.

Now to find something else to use with D cells..... a TK70 perhaps???

oh the wife would kill me......


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## JudasD (Mar 10, 2012)

fireballtp said:


> I would like to persoanlly thank the OPs of this thread. I was able to get 16 Blue D Tenergys for use in my Mr Beams/Dorcy Porch lights. Even if these aren't the best batteries, they will still save a bundle over time.
> 
> Now to find something else to use with D cells..... a TK70 perhaps???
> 
> oh the wife would kill me......



The TK70 is a great light! Even if the wife does kill ya, it just might be worth it! :lolsign:

JD


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## Sagebrush (Mar 10, 2012)

Thinking back to old reviews of the blue D cells I remember them saying they were in the 8,000 range.

So, that was what l expected. 

I bought them for my maglites and my tent fan. Good deal for the price. :thumbup:

Sent from my GT-S5690L using Tapatalk


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## Quest4fire (Mar 10, 2012)

I have not seen anymore blue Tenergy D cells in marrsinc's listings in a day or two now. :sigh: Hope everyone who was thinking about getting some pulled the trigger on time. Thanks again drmalenko for the heads up.


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## JudasD (Mar 10, 2012)

Sagebrush said:


> Thinking back to old reviews of the blue D cells I remember them saying they were in the 8,000 range.
> 
> So, that was what l expected.
> 
> ...



I should have done more research before i bought them. i thought they would be true 10k cells like the other tenergys. Right now my Centura 8,000s are getting higher capacity numbers than these blue cells with the added benefit of being LSD. Ill probably just buy some true Tenergy Premium 10k and sell these blue cells. I dont really have a need for them now.

JD


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## sadtimes (Mar 12, 2012)

Quest4fire said:


> I have not seen anymore blue Tenergy D cells in marrsinc's listings in a day or two now. :sigh: Hope everyone who was thinking about getting some pulled the trigger on time. Thanks again drmalenko for the heads up.



Anytime! Hope you scored enough of them!


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## CyberCT (Mar 13, 2012)

The Break-in mode on the C9000 is complete for 8 of the 16 blue Tenergys I have. They are showing up about 600 mah higher during break-in cycle than with the 1 amp discharge. My highest is just under 9,100 mah. I set the total capacity during break-in to 9,000 mah.


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## Eneloops (Mar 19, 2012)

I've always wanted to use those plastic adapters, the ones you stick a AA cell into, and it becomes "D sized" - just to have the lightest weight, biggest flashlight with extremely poor run time.


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## CyberCT (Mar 19, 2012)

Kind of a "duh" but after spending much time doing multiple mah capacity tests on my 16 Tenergys and battery matching them in fours (4 best, then next 4, then next 4, last worst 4), here are my runtime results on the TK70 on turbo mode for the 4 best and 4 worst:

Best 4 batteries (8,708 8,603 8,556 8,410)
1 hour 10 minutes 35 seconds until light drops to high from turbo

Worst 4 batteries (7,784 7,673 7,532 7,228)
57 min 41 sec

The driver starts to squeal around 45 minutes or so and it is a little annoying. Would be an issue snorkeling at night with this thing, the sound would probably scare the fish away. Since the 1 D cell adapter piece can fit on the end, I wonder if it can fit between the head of the TK70 and the 3D tube. Because if it can I could technically have a 5 D cell light underwater and it wouldn't be too heavy because all I'm doing is swimming with the light. Fenix distributors online supposedly have spare parts. I'll have to look into this. If that 5th battery is in there I wonder if it will be enough voltage to keep that squealing from happening until at least over an hour. With just 3 D batteries the light squeals on turbo from the moment it is turned on till it drops to high 40 some minutes later.
EDIT: 1D extension will NOT fit between the head and 3D tube.

The only thing I can think of for the worst 4 and second to worst 4 D cell batteries would be for my two modified Rayovac Sportsman Xtreme lanterns (take 3 D cells each). I put neutral XMLs in them and used Shiningbeam's 3-mode max 1.4a driver. These batteries should provide about 5 - 6 hours on the highest mode of constant use, and tripple that on the medium setting which is plenty bright. Perfect for camping.

http://www.shiningbeam.com/servlet/the-133/3-dsh-Mode-Regulated-Circuit-Board/Detail


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## 357mag1 (Mar 20, 2012)

CyberCT said:


> If that 5th battery is in there I wonder if it will be enough voltage to keep that squealing from happening until at least over an hour. With just 3 D batteries the light squeals on turbo from the moment it is turned on till it drops to high 40 some minutes later.
> EDIT: 1D extension will NOT fit between the head and 3D tube.
> http://www.shiningbeam.com/servlet/the-133/3-dsh-Mode-Regulated-Circuit-Board/Detail



If you have an extra 1D extension it will add right onto the previous 1D extension and that is how I run one of my TK70s. Per the chart I sent you it should give you close to two hours runtime and I doubt the driver would start squealing except maybe right at the end of the run.


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## CyberCT (Mar 20, 2012)

357mag1 said:


> If you have an extra 1D extension it will add right onto the previous 1D extension and that is how I run one of my TK70s. Per the chart I sent you it should give you close to two hours runtime and I doubt the driver would start squealing except maybe right at the end of the run.



I think I'm going to order one. I'll contact a Fenix dealer later on.

I did runtime tests on turbo for my other 8 Tenergys. These are the two mid groups. I wanted to see if they were closer to 1 hour 10 minutes or 1 hour just for the heck of it. To my surprise they were MUCH closer to 1 hour for some reason. Maybe because the sat off the charger for an extra day? That can't make this much of a difference though.

2nd best 4 batteries (8,346 8,194 8,100 8,027)
1 hour 1 minute 47 seconds until light drops to high from turbo

3rd best 4 batteries (7,980 7,961 7,844 7,814)
1 hour 0 minutes 42 seconds until light drops to high from turbo


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## hank (Apr 6, 2012)

I belatedly got a D cell adapter started checking my Tenergy Ds -- connected via wires, alligator clamps and magnets -- to the contacts of my Maha 9000 charger.

So far all of them show HIGH -- I'm wondering if I've just got too much resistance added by the wires/clamp/magnet.
I'll try the method CyberCT suggested earlier: http://www.candlepowerforums.com/vb...-D-quot-cell&p=3881284&viewfull=1#post3881284

If I can figure out how to solder wire to those little adapter things without melting the plastic case, that should give better contact.

On a slower (CCrane) charger the Tenergys do show as charging. That charger will test voltage one cell at a time, and I'm showing 1.36 or 1.37v.


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## CyberCT (Apr 6, 2012)

hank said:


> I belatedly got a D cell adapter started checking my Tenergy Ds -- connected via wires, alligator clamps and magnets -- to the contacts of my Maha 9000 charger.
> 
> So far all of them show HIGH -- I'm wondering if I've just got too much resistance added by the wires/clamp/magnet.
> I'll try the method CyberCT suggested earlier: http://www.candlepowerforums.com/vb...-D-quot-cell&p=3881284&viewfull=1#post3881284
> ...



Hmmm what do you mean by they read HIGH? If you mean those AAA to AA adapters, what I did to avoid melting the plastic was poke the metal contact points on the (+) and (-) sides of each battery adapter out, and then solder my wire to them. Then snap them back into the plastic adapters. I drilled a small hole for each side of the battery adapter to feed the wire through. The solder wouldn't stick too well to the metal contact points, so I ended up cutting a dowel down to an AAA size and placed one in each the AAA to AA adapters. It made the fit inside so snug that it forced the wire to touch the metal contact points with no play. Then I taped the part where the AAA to AA adapters come apart in two, just to make sure they don't come apart and the dowel keeps the contacts touching inside the adapter (between the wires and metal contact points). I have run many tests on these and they stil work well. My copper wire running from each AA to AAA adapter to D cell adapter is about 20 gage or so, and about a foot in length.

Hope this helps.


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## TEEJ (Apr 6, 2012)

The WHITE wrapped Tenergy D Cell NiMH are better than the BLUE versions. They are called PREMIUM sometimes.

The white ones tend to be truer to the 10k mah rating than the blues.


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## hank (Apr 6, 2012)

> read HIGH
That's what appears on the Maha 9000 display.

I haven't tried the little battery adapters yet; they ought to give better contact. Ah, you're right, the metal bits do pop out fairly easily, thanks. Looks like the contacts are chromed steel, maybe a lick with a file or sandpaper will remove some chrome and make solder stick better.

I've had a Tenergy D in an external holder, and the alligator clips on its wires held to the Maha charging contacts with magnets. 
(ps, looked under the shrinkwrap, the wires were just squeezed into the alligator clips; I've soldered them now, will retry; may need bigger wire)

I'll try your method for the battery case.


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## WDG (Apr 9, 2012)

CyberCT said:


> Hmmm what do you mean by they read HIGH?



On the MH-C9000, a "HIGH" reading normally means that the charger is rejecting the cell as having too high internal resistance. This usually happens with aging NiMh cells, or if alkalines are accidentally inserted.

If the cells are new, I would think it more likely that adapter connection set-up is adding too much resistance, rather than it being in the cells themselves. I could, of course, be mistaken.


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## hank (Apr 17, 2012)

I'm describing the Tenergy Ds (blue wrap, 10,000, the ones this thread started about -- from the discount supplier.

These Ds do hold charge, they show somewhere between 1.3 or 1.4v when full, but are inconsistent after several discharge/charge cycles. They still read "HIGH" on the MH-C9000 charger. 

The old Tenergy AAs from the same source were similarly weak.


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## rdljr1 (Dec 15, 2012)

Hey guys, I'm new to this forum. Just got the flashlight bug a few months ago and it's quickly become an addiction!  Anyway, I have both the blue standard Tenergy D cells and I just purchased the premium white Tenergy D cells for my Fenix TK70. After I charge the white premiums I've noticed that the voltage has been dropping from 1.4v to 1.38 and now to 1.36 in the span of about 2 days in storage as the blues are still going good in the TK70. Is this a normal discharge rate? It seems rapid to me but again I'm pretty new to this. I hadn't noticed the drop with the standard blue Tenergy's before, but maybe I just wasn't checking as frequently. I'm using a Fluke 115 multimeter for my measurements. Thanks for your help guys!


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## StorminMatt (Dec 16, 2012)

rdljr1 said:


> Hey guys, I'm new to this forum. Just got the flashlight bug a few months ago and it's quickly become an addiction!  Anyway, I have both the blue standard Tenergy D cells and I just purchased the premium white Tenergy D cells for my Fenix TK70. After I charge the white premiums I've noticed that the voltage has been dropping from 1.4v to 1.38 and now to 1.36 in the span of about 2 days in storage as the blues are still going good in the TK70. Is this a normal discharge rate? It seems rapid to me but again I'm pretty new to this. I hadn't noticed the drop with the standard blue Tenergy's before, but maybe I just wasn't checking as frequently. I'm using a Fluke 115 multimeter for my measurements. Thanks for your help guys!



Have you measured the blues and confirmed that they're NOT similarly dropping over the course of two days? Anyway, neither the blue standard nor the white Premium batteries are LSD. So I would expect voltage to drop as you say. In fact, from what I have heard, non-LSD batteries can lose around 20% of their capacity in the 24 hour period after charging. So what you describe wouldn't be too out of line. That's probably the biggest reason why non-LSD batteries are best for use immediately after charging.


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## Power Me Up (Dec 16, 2012)

rdljr1 said:


> After I charge the white premiums I've noticed that the voltage has been dropping from 1.4v to 1.38 and now to 1.36 in the span of about 2 days in storage



That's actually completely normal for NiMH rechargeables - the voltage will always settle after charging - even the low self discharge type do this.


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## tatasal (Dec 16, 2012)

Even LSDs will normally settle to 1.28V


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## 357mag1 (Dec 18, 2012)

rdljr1 said:


> Hey guys, I'm new to this forum. Just got the flashlight bug a few months ago and it's quickly become an addiction!  Anyway, I have both the blue standard Tenergy D cells and I just purchased the premium white Tenergy D cells for my Fenix TK70. After I charge the white premiums I've noticed that the voltage has been dropping from 1.4v to 1.38 and now to 1.36 in the span of about 2 days in storage as the blues are still going good in the TK70. Is this a normal discharge rate? It seems rapid to me but again I'm pretty new to this. I hadn't noticed the drop with the standard blue Tenergy's before, but maybe I just wasn't checking as frequently. I'm using a Fluke 115 multimeter for my measurements. Thanks for your help guys!



In my experience all rechargeable nimhs settle out to around 1.3v after they have been off the charger for a certain amount of time. The time varies with each battery type and manufacturer lot.

I have some Eneloops (best nimh LSD) that were charged two days ago and they are still around 1.4v and may take a month to drop down to 1.3v but they will. The Blue Tenergy D cells aren't true 10,000mah cells or at least none of the ones I've tested have reached much over 8000mah. Tenergy Premium (white cells) are true 10,000mah cells so the internal chemistry is slightly different and they will measure different than the Blue cells.

I have run discharge test on both cells and the Tenergy Premium will have more capacity left after 6 months setting unused off the charger than the blue cells do fresh. I've verified this several times with several different batches of cells.

Keep in mind even with just a 2 or 3 amp load both cells will drop to 1.2v under that load so the static voltage doesn't tell you a whole lot about the cell.

In my testing the Tenergy Premium D cell is better than any other D cell on the market.

Hope that helps.


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## mccririck (Dec 19, 2012)

Thought I'd let people in the UK know that from Thursday Lidl will be selling rechargeable D cells, they are LSD I think, capacity is 4500mAh, the AA are 2100mAh and the C are 4000mAh, they are also doing AAA (850mAh) and 9V (200mAh)


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## coachtjm (Dec 20, 2012)

Looking at a similar light to tk70, that requires D cell batteries...can you use the eneloops with the adapters or is this unsafe? not recommended? etc? new to this also...


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## mccririck (Dec 20, 2012)

coachtjm said:


> Looking at a similar light to tk70, that requires D cell batteries...can you use the eneloops with the adapters or is this unsafe? not recommended? etc? new to this also...




You can use Eneloops with adaptors but their capacity is only 2000mAh which defeats the point of a D cell light.


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## StorminMatt (Dec 21, 2012)

mccririck said:


> You can use Eneloops with adaptors but their capacity is only 2000mAh which defeats the point of a D cell light.



A point well taken. One HUGE advantage of D batteries vs smaller batteries (like AA batteries) is runtime. With Eneloops in adaptors, you will get only a quarter to a fifth of the runtime of a true size D NiMH. This isn't going to be very long with a TK70 on Turbo.

Speaking of a TK70 on turbo, another issue with Eneloops is going to be internal resistance. Although even a NiMH AA battery is going to have a low internal resistance, the internal resistance of an Eneloop is going to be several times higher than, say, a Tenergy Centura D battery. Given that a TK70 on Turbo is going to be drawing some MAJOR amps, true D batteries are going to be able to hold their voltage better than AA batteries.


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## mccririck (Dec 21, 2012)

Are Tenergy Centura D the best value?


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## StorminMatt (Dec 21, 2012)

mccririck said:


> Are Tenergy Centura D the best value?



All of the Tenergy D cells seem to go for around $16 a pair. So whether the Premiums or the Centuras are a better value depends on your use of the batteries. The Centuras are LSD batteries. And, accordingly, they are lower in capacity than the Premiums (8000mAH vs 10000mAH). It all comes down to whether you need a battery that is going to give you maximum capacity to all be used in pretty much one shot right after charging vs something that will be able to hold its charge for intermittent use over a period of months.


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## Verminator (Dec 22, 2012)

357mag1 Thank you for all your great testing info on D cells. I'm sold on the Tenergy Premiums based on your reviews already! A question I have though is, in your opinon, are these batteries also suitable for childrens toys that take D cells? I know this forum is primarily for "flashlight users" but about the only other thing that takes D cells are toys and that is my interest. Assuming they are, what is the best charger for D cells? I have a MH-C9000 my my AA and AAA cells and find it excellent. I'm really happy with that charger and I see Powerex does have D charger. What is your opinion of that?

Finally, have you done any testing on 9V batteries? If so, I see there is also a Tenergy Premium version of them, however I have no idea they only held 2500 mAh on average! For some reason I expected a 9V would have a much larger capacity...but I guess not??


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## K9Patrol (Dec 22, 2012)

Just for the record I have lots of Tenergy Centura cells (16 D, prob. about 60 AA, about the same AAA, 4 9 volts). I've had absolutely zero problems with them and they work great. Haven't seen any bad reviews of them either.

One thing about using multiple cells in a device is that you dont want to ever let them drain until their completely dead - Chances are one of the cells will be weaker than the rest and will get reverse charged. I see this every time I run down alkalines, and have ruined some older Energizer NiMH cells that way (the weak one which got reversed charged read 0.000 volts when I took it off the charger because it defected on it)

I left it on the shelf and eventually it recovered enough to put it on the charger, though running it through a test cycle showed that it only held 1600ma after that, and it was a 2100ma battery..

Not scientific, just observation.


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## ArcticHighlander (Dec 22, 2012)

357mag1 said:


> In my experience all rechargeable nimhs settle out to around 1.3v after they have been off the charger for a certain amount of time. The time varies with each battery type and manufacturer lot.
> 
> I have some Eneloops (best nimh LSD) that were charged two days ago and they are still around 1.4v and may take a month to drop down to 1.3v but they will. The Blue Tenergy D cells aren't true 10,000mah cells or at least none of the ones I've tested have reached much over 8000mah. Tenergy Premium (white cells) are true 10,000mah cells so the internal chemistry is slightly different and they will measure different than the Blue cells.
> 
> ...



Thanks, 357mag1. I read threw this entire thread and your information has been invaluable. I just ordered a TK70 and a set of 8 Tenergy Premiums for $50 to go with it. Along with the Maha 808m charger. I'd also like to get a TK35 and saw somewhere in this thread that you had a good source at a good price located in the US for Fenix. Could you PM me with the info? I don't have enough posts yet to contact you directly.


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