# 2800MaH AA Ni-mH rechargeable



## john2551 (Dec 25, 2005)

I was wondering if any CPF battery experts have put any 2800MaH AA cells to the test. I found these 2 brands on ebay:

http://cgi.ebay.com/Rechargeable-Batteries-4-x-2800mAh-AA-NiMH-1-2V_W0QQitemZ7572998699QQcategoryZ43445QQrdZ1QQcmdZViewItem

&

http://www.sparedollar.com/viewpic.asp?imgurl=http://members.sparedollar.com/ksood/aa_2800_01(2).jpg


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## IsaacHayes (Dec 25, 2005)

Hmm. I don't reconize either brand so it may be inflated claims... AFAIK, 2500/2600 is the tops right now.. but I could be wrong....


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## paulr (Dec 25, 2005)

I wouldn't believe that rating enough to bother testing them, unless someone gave me the cells for free.


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## jar3ds (Dec 25, 2005)

yeah... 2600 max right now.. i'm using energizer 2500... thats pretty dang good... =-P


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## BatteryCharger (Dec 25, 2005)

I'd put alot of money on them being no more than 2300...if that...


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## N162E (Dec 25, 2005)

BatteryCharger said:


> I'd put alot of money on them being no more than 2300...if that...



I'll take that bet. What do you call a lot?


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## wptski (Dec 25, 2005)

Tamiya is a big name in RC stuff!


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## baylisstic (Dec 25, 2005)

I was gona say the same. Tamiya is a respectable brand in RC and if those really are genuine Tamiya brand, I believe them.


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## N162E (Dec 25, 2005)

baylisstic said:


> I was gona say the same. Tamiya is a respectable brand in RC and if those really are genuine Tamiya brand, I believe them.


Just as soon as *BatteryCharger* puts his money where his mouth is we are going to find out how good these batteries are. One of us could be doing this group a real service.


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## BatteryCharger (Dec 25, 2005)

I'm pretty sure betting would be against the CPF rules. 

2800mah from an unknown brand for about a buck on ebay? Come on now...if you believe that I want some of whatever you're smoking...


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## VidPro (Dec 25, 2005)

oh please sombody bet, put some big money on it, so we can find out the truth.
i am thinking a high of 2.59 max.
but i am with the naysayers on this one, with some cute tricks you can scew any specs. just run it totally flat, they didnt mention what Voltage it actually maintained when it hit that last ma.

so were going to need some parameters for the betting. like a discharge rate, and a low voltage stopping location.


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## Luna (Dec 25, 2005)

Do a google on Tamiya.

Remember RC is a major driving force of rechargable cell technology and they (Tamiya ) are a playa 

edit:That was to BC


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## N162E (Dec 26, 2005)

BatteryCharger said:


> I'm pretty sure betting would be against the CPF rules.
> 
> 2800mah from an unknown brand for about a buck on ebay? Come on now...if you believe that I want some of whatever you're smoking...


You started it. If you feel so sure you are right it should be a slam dunk for you. Put up or shut up. If you are worried about CPF rules, we can use another forum. 2800 is a real push but all I need is over 2300. When I say something I mean it, Don't you? If you don't intend to honor your word at least stop arguing about the potential of these cells.


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## N162E (Dec 26, 2005)

VidPro said:


> oh please sombody bet, put some big money on it, so we can find out the truth.
> i am thinking a high of 2.59 max.
> but i am with the naysayers on this one, with some cute tricks you can scew any specs. just run it totally flat, they didnt mention what Voltage it actually maintained when it hit that last ma.
> 
> so were going to need some parameters for the betting. like a discharge rate, and a low voltage stopping location.


I agree. May I suggest a cutoff of 1 volt at a 500ma rate. We will also need a tester (Maybe Silverfox) and a person to act as escroe agent (Maybe WPTSKI) I am open for ideas on how to proceed. If this is a little over the edge for out here we could take it "Underground"


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## BatteryCharger (Dec 26, 2005)

You really need to calm down, dude. This kind of abrasive attitude is not welcome on CPF. If you want to test the cells put your money where YOUR mouth is and buy some. Prove me wrong.


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## CLHC (Dec 26, 2005)

And so spoke "The crazy guy next door"—If I recall, there's somewhere I saw/read about DigiPower and also Panasonic having 2800mAh NiMH rechargeable batteries for sale. I thought I saw that the Panasonic ones were "Made in Japan" but don't know about the DigiPower ones. . .Enjoy!


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## VidPro (Dec 26, 2005)

i put a bid on a set from there, a different set so i wouldnt mess with the OPs bid.
i can test them AGAINST others, using the same method as others.

but i have tested many of these now
powerizers, IMO total fraud the specs
powerUS , same thing
maha cells didnt last time
energyser high cap, still testing, high today, over spec in testing, but untill i test them for long , wont know
sunoco , of all things came very close to spec, close enough to concider that they could get to thier specs.

i will try these thing, if i dont have to pay much for them.
price for capacity so far, sunoco things for the price i got em was great.
but energyser 2300s i have tested since they came out, and retested when the 2500s came out, and they are STILL at spec.

all my tests and asumptions are just based on USE, then testing every once in a while. like anybody who wants massive capacity, i have seeked it out at every claim, and have gotten burned far more times than not.

i always get near the same results as silvers tests, but certannly dont have a CBA, or even care if things are off by .1 here and there.


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## wptski (Dec 26, 2005)

Sometimes new cellphones, etc. are released in other markets first before they are here which could be possible with these cells.


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## wptski (Dec 26, 2005)

CHC said:


> And so spoke "The crazy guy next door"—If I recall, there's somewhere I saw/read about DigiPower and also Panasonic having 2800mAh NiMH rechargeable batteries for sale. I thought I saw that the Panasonic ones were "Made in Japan" but don't know about the DigiPower ones. . .Enjoy!



Is there "any" Ni-MH cells made in the USA? I really don't know!


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## N162E (Dec 26, 2005)

BatteryCharger said:


> You really need to calm down, dude. This kind of abrasive attitude is not welcome on CPF. If you want to test the cells put your money where YOUR mouth is and buy some. Prove me wrong.


You started this, prove me wrong. You are not an administrater here and not in a position to tell me what is appropriate behavior here.


BatteryCharger said:


> I'd put alot of money on them being no more than 2300...if that...


My money is where my mouth is, Where is your's? Either put up or slither away.


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## BatteryCharger (Dec 26, 2005)

N162E said:


> This message is hidden because N162E is on your ignore list.



Did somebody say something?


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## AdamW (Dec 26, 2005)

N162E said:


> My money is where my mouth is, Where is your's? Either put up or slither away.



OWNED!


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## jayflash (Dec 26, 2005)

Geez, it's the Christmas season, let's keep this fun. Sometimes we overstate without being all that serious (just for fun) and sometimes we are misunderstood. Having put-foot-in-mouth myself, may I ask that we abstain, further, from personal duels? Please.


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## [email protected] (Dec 26, 2005)

Hmm, I would have liked it when the Christmas Spirit would have lasted a while longer... :sigh:

Let's not go there guys, and just discuss the batteries please?
Thanks.


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## N162E (Dec 26, 2005)

This has gone too far and it is my fault. This is supposed to be fun and I took it too far. I am in FL now but will be home on Jan. 9. I am curious to see how these cells perform. If no one else has done a test by the time I get home I will get some cells and run a test myself. As for BatteryCharger, I'll concede either way the test goes, his prize will be lunch with WPTSKI and me. :buddies:


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## CLHC (Dec 26, 2005)

wptski said:


> Is there "any" Ni-MH cells made in the USA? I really don't know!




That's a good question, because so far, of all the rechargeable batteries that I've seen whether it's for RC, Cordless Power Tools, Flashlights, and others, they (rechargeable batteries) have either Made in Japan or China on it. . .


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## TrueBlue (Dec 26, 2005)

For scientific interests and my own curiosity I won the auction at Ebay for a set of Tamiya AA batteries. $7.99 was the final cost. One penny to buy, $6.99 for shipping and 99 cents for insurance will get the batteries to my door.

If the batteries have a capacity of over 2500mA then I’ll be happy. The battery “maker”, Tamiya, is big company in Japan. It specializes in models and Radio Controlled products. For the RC crowd I would think Tamiya would sell premium batteries. AA batteries of over 2500mA would be a good sell for the company. If the batteries came close to 2800mA then it would be a big leap in run time for our lights.

I do have the La Crosse charger. I suppose setting the charger for “Refresh” mode would tell me the final capacity of the batteries. .9V is the cut off for discharge and the smart charger will know when to stop charging.

Testing the Tamiya battery next to a known battery in a light would be good. I do have Energizer 2500mA AA batteries to compare against.

I might have an advantage over a reviewer testing the batteries. My batteries are bought ‘off the street’ and would be an end consumer product.

I wonder how long the shipping will take from Hong Kong?

Hold on scientists, some Tamiya batteries are coming to the US.


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## jeffb (Dec 26, 2005)

N162E (Fred),

:goodjob: !


jeffb


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## wptski (Dec 26, 2005)

TrueBlue:

I ordered a laser a while back from Hong Kong and got it in a week but that may not be the norm!


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## TrueBlue (Dec 27, 2005)

Thanks wptski. For the shipping cost then I'd think the mail would come from the air and not from the sea.

I hope.

I should get the batteries as soon as they hit the US since I'm on the Pacific side.


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## balazer (Dec 27, 2005)

If I remember correctly, the BC-900 will only put 3000 mAh into a battery during a charge cycle. Take that into consideration in your testing.


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## TrueBlue (Dec 27, 2005)

I did think about that. Thanks, balazer. I doubt the batteries will get near 3000mA.


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## John N (Dec 27, 2005)

FWIW, I'd like to see a discharge graph at 5 Amps, ala Silverfox's NiMh shootout. It seems like the 5 Amp discharge rate is at the edge for the high capacity AA batteries. The top performers (over >=2 Ah) to date seem to be:

Energizer AA 2500 - 2.163 Ah
Sanyo Industrial AA 2500 - 2.192 Ah
AccuPower AA 2600 - 2.085 Ah
Titanium AA 2600 - 2.121 Ah
Vapextech AA 2500 - 2.049 Ah

So it looks like 2.192 Ah @ 5 Amp is the one to beat.

-john


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## wptski (Dec 27, 2005)

balazer said:


> If I remember correctly, the BC-900 will only put 3000 mAh into a battery during a charge cycle. Take that into consideration in your testing.


balazer:

The manual states using slots 1&4 the max. charging current is 1800ma. Any other pair or all four slots, max. charging current is 1000ma.


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## TrueBlue (Dec 27, 2005)

During charging the higher charge rates mean warmer batteries. Does the BC-900 mA indicator adjust its readings to compensate for the extra heat-energy being wasted?


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## SilverFox (Dec 27, 2005)

Hello TrueBlue,

No.

It also does not adjust for any heat developed during the discharge cycle.

Tom


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## InfidelCastro (Dec 27, 2005)

I'd sure love something close to 3Ah for a 2D-6AA Mag mod. The Energizer 2500mAh's seem to last forever in my digital camera though. In fact I haven't even gotten them to die, I just recharge them every once in awhile so they don't become too discharged.


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## Agent_K (Dec 27, 2005)

InfidelCastro said:


> I'd sure love something close to 3Ah for a 2D-6AA Mag mod. The Energizer 2500mAh's seem to last forever in my digital camera though. In fact I haven't even gotten them to die, I just recharge them every once in awhile so they don't become too discharged.



How about 3600mAh...












I don't remember where I found these pics, anyone know if these are for real?


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## IsaacHayes (Dec 27, 2005)

wow, that can't be right. That's getting close to C NiMH territory!


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## InfidelCastro (Dec 27, 2005)




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## balazer (Dec 27, 2005)

wptski said:


> The manual states using slots 1&4 the max. charging current is 1800ma. Any other pair or all four slots, max. charging current is 1000ma.


I was talking about charge (mAh), not current (mA). The maximum charge for a charging cycle in the BC-900 is 3000 mAh.


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## MSI (Dec 27, 2005)

My bet is that the batteries are pirate versions, both the Tamiya and the Panasonics. There have been reports on CPF before of pirated batteries.


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## CLHC (Dec 27, 2005)

On the Panasonic's official website, their newest AA batteries were the 2800mAh. There was nothing on them 3600mAh AA. . .So I don't know about that and those pictures. Maybe indicative of what IsaacHayes and MSI alluded to.


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## TrueBlue (Dec 27, 2005)

Brazil, of all places, seems to have a rash of 3600mAh NiMH batteries that are labeled Sony. Sony claims they make only 2100mAh NiMH batteries. The Panasonic 3600mAh batteries could be another fake.

From Dan’s Data about Sony 3600mAh AA fake battery.


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## wptski (Dec 27, 2005)

balazer said:


> I was talking about charge (mAh), not current (mA). The maximum charge for a charging cycle in the BC-900 is 3000 mAh.


balazer:

If you have a 1000mAh capacity cell, what's the typical max current rate that you charge at? 1C or 1000ma, correct? The mAh is a cell's capacity and the charger ability to charge is in ma.

I think I know what your trying to say because I've heard that too. The BC-900 can only measure capacity up to 3000mAh. Is that it??


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## CLHC (Dec 27, 2005)

Interesting link there TrueBlue. Nowadays one cannot always be so sure eh? Man Alive. . .Just sit, wait and see.


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## TrueBlue (Dec 27, 2005)

No one knows more about the Panasonic 3600mAh batteries? Do I dare to ask if they are sold in Brazil? :thumbsdow 



I’ve been in contact with the Ebay seller of the Tamiya 2800mA batteries. I told him the story about how this, unknown to him, forum is watching the batteries and I was going to test the set. His reply,

_“We do the retail for this batteries & we're not the producer of this product. These batteries are selling very good in our place but we never do any test to them. 
Thank you for your test & we don't know how to join the forum. But we willing to give discount if large quantity order. 

Thank you for your interest to our products.

*Name withheld”_

See if he joins CPF since I sent him a link. Everyone keep an eye out for him.


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## balazer (Dec 28, 2005)

wptski said:


> balazer:
> 
> If you have a 1000mAh capacity cell, what's the typical max current rate that you charge at? 1C or 1000ma, correct? The mAh is a cell's capacity and the charger ability to charge is in ma.
> 
> I think I know what your trying to say because I've heard that too. The BC-900 can only measure capacity up to 3000mAh. Is that it??


I'm saying that the BC-900 will only put 3000 mAh of CHARGE into the batteries during a charging cycle. That's "charge" as a noun, as we use the word in electricity and physics. Think of charge as a number of electrons, and current as a rate of electron flow, i.e. electrons per second. If you set the charging current to 1000 mA, the BC-900 will stop after 3 hours. If you set the charging current to 500 mA, the BC-900 will stop after 6 hours. Get it? The 3000 mAh charging limit is a safety feature of the BC-900, to prevent it from frying the cells if it should fail to detect the end-of-charging conditions.

The issue is that charging of NiMH cells is less than 100% efficient. If these batteries turned out to have an actual capacity of 2800 mAh, you'd need to put something like 3200 mAh (I'm guessing) into the batteries to fill them up. There's a way around the problem, if necessary.


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## ChrisA (Dec 28, 2005)

@agent_k - it really is that simple...







that's a two minutes ps work on the picture you posted. whoever brought that picture up, had a better source to manipulate... these are fakes for sure !

chris


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## wptski (Dec 28, 2005)

balazer said:


> I'm saying that the BC-900 will only put 3000 mAh of CHARGE into the batteries during a charging cycle. That's "charge" as a noun, as we use the word in electricity and physics. Think of charge as a number of electrons, and current as a rate of electron flow, i.e. electrons per second. If you set the charging current to 1000 mA, the BC-900 will stop after 3 hours. If you set the charging current to 500 mA, the BC-900 will stop after 6 hours. Get it? The 3000 mAh charging limit is a safety feature of the BC-900, to prevent it from frying the cells if it should fail to detect the end-of-charging conditions.
> 
> The issue is that charging of NiMH cells is less than 100% efficient. If these batteries turned out to have an actual capacity of 2800 mAh, you'd need to put something like 3200 mAh (I'm guessing) into the batteries to fill them up. There's a way around the problem, if necessary.


balazer:

I get what your trying to say now. Where did you get your information from? I wonder if that's similar to what I heard about it only being able to calculate up to 3000mAh?

I may try to attach a depleted 5500mAh Ni-MH "C" and see if this is true.

The way people have been melting the BC-900's lately, this doesn't seem to work!


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## InfidelCastro (Dec 28, 2005)

TrueBlue said:


> _“We do the retail for this batteries & we're not the producer of this product. These batteries are selling very good in our place but we never do any test to them.
> Thank you for your test & we don't know how to join the forum. But we willing to give discount if large quantity order.
> 
> Thank you for your interest to our products.
> ...




Ebay engrish always makes me weary.

We don't know how to join the forum? Wtf?

Anyways, it'll be interesting to see how these batteries perform.


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## balazer (Dec 28, 2005)

wptski said:


> balazer:
> 
> I get what your trying to say now. Where did you get your information from? I wonder if that's similar to what I heard about it only being able to calculate up to 3000mAh?


I think I read it in the manual.


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## wptski (Dec 28, 2005)

balazer said:


> I think I read it in the manual.


balazer:

I called La Crosse today because I was curious about this. The Tech that I spoke said that the BC-900 has been tested on 2600mAh cells and worked. I pressed about any limits and he left the phone to check with someone else that knew the BC-900 better. The answer was that there is no know limits in respect to capacity but metioned the temperature cutoff and suggested using the 200ma settings on larger capacity cells.


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## TrueBlue (Dec 28, 2005)

Wptski, would ‘larger capacity cells’ mean larger than 2600mA? A lowest charge rate of 200mA on the BC-900 makes it hard for the charger to figure out the cut-off voltage.

The rep ‘suggested.’ Does that mean he is not sure? No answer is necessary; we all do not know.

Any test of the ‘2800mA’ batteries is better than buying blind.

Thanks for taking the time to call La Crosse and sharing the info with us.


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## Haz (Dec 28, 2005)

Don't trust all the figures you see, some are inflated to sell the batteries. I have used other cheap brands, that retains little charge over 1 or 2 days, and don't hold much charge.


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## wptski (Dec 28, 2005)

TrueBlue said:


> Wptski, would ‘larger capacity cells’ mean larger than 2600mA? A lowest charge rate of 200mA on the BC-900 makes it hard for the charger to figure out the cut-off voltage.
> 
> The rep ‘suggested.’ Does that mean he is not sure? No answer is necessary; we all do not know.
> 
> ...


TrueBlue:

Yes, larger than the tested 2800mAh. Yes again, sounds like they aren't really sure, so the suggestion to slow charge. I didn't bring up the point that some have suggested that a slow charge might not terminate. I might add that I've never had that happen myself. It seems that the BC-900 has a problem with larger new cells but I don't remember if the user stated that a slow charge was used. :thinking:


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## N162E (Dec 28, 2005)

wptski said:


> balazer:
> IThe way people have been melting the BC-900's lately, this doesn't seem to work!


Has this happened with any stock BC-900s? As I recall several of the overheat problems happened when people used the 3.3 volt Cisco adapter or in some other way tampered with the charger.


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## nikon (Dec 28, 2005)

N162E said:


> Has this happened with any stock BC-900s? As I recall several of the overheat problems happened when people used the 3.3 volt Cisco adapter or in some other way tampered with the charger.


 

Please see my previous post. My charger and adapter are just as supplied by the manufacturer.


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## SilverFox (Dec 28, 2005)

Hello TrueBlue,

When you get your new cells, I would suggest you follow the following procedure for charging them.

Put them into your BC-900 and select the Discharge mode. The default discharge current of 100 mA will be perfect. It may take a while for the discharge to complete, but this is an important step in "forming" your cells. At the end of the discharge cycle, the BC-900 will switch to charging at 200 mA. This is the charge current we want, so just let it go. Pay attention to the time when it enters the charge mode. 18 hours after it starts charging, shut the charger off and pull the cells. This is the end of the first charge.

You need to keep an eye on the cell temperature during this first charge. If the cells get hot, stop the charge by removing the cells from the charger and let them cool down. They should not start to warm up until the end of the charge time.

Your cells should now be formed and after they have cooled down, you should be ready to do a test cycle.

To test the cells, put them in the BC-900, select the test mode, and select EDIT: _500 mA as the discharge current_ this should read select 1000 as the charge current. END EDIT The BC-900 will first charge the cells up at 1000 mA. You need to keep an eye on cell temperature during this part of the test. Then the discharge will begin, and should run for around 5.5 hours. Once the discharge is complete, the charge cycle will start. Once again you need to keep an eye on the cell temperature toward the end of the charge cycle. It should take around 3.5 hours to charge back up and the last hour is probably the most critical time to watch the cell temperature.

While the BC-900 does have a high temperature cut off feature, it is set quite high and does not terminate the charge. It will stop charging and let the cell cool down, but once the temperature drops, it will start charging again and drive the temperature back up. The temperature cut off on the BC-900 is specified at 165 F. This seems like it is a bit too hot. I am checking out the Maha C808M charger, and its high temperature cut off is set at 120 F. That seems a lot more reasonable to me.

While I have not had any problems with high temperatures while using the BC-900, there are a few reports of others experiencing some "melt downs."

Once you have completed a test cycle. Feel free to do another one. After completing two complete cycles, it is probably OK to hit the refresh mode and see if the capacity will increase. Once you have 4 or 5 cycles on the cells, it is time to do the "official" test to see how they do.

This procedure will give you the best chance of properly forming and conditioning your new cells and should yield the highest capacity from them.

Tom


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## wptski (Dec 28, 2005)

N162E said:


> Has this happened with any stock BC-900s? As I recall several of the overheat problems happened when people used the 3.3 volt Cisco adapter or in some other way tampered with the charger.



N162E:

There was another thread started about a meltdown where is was a new Xmas gift, no mention of anything odd being down!


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## wptski (Dec 28, 2005)

Tom:

Darn CPF locked me up when I to "quote" you!

I never used the Discharge Mode yet. I good explanation as usual but you have a slight mistake in the Test Mode procedure. The user selects the Charge current which is twice the Discharge current. I think you were stuck in Discharge Mode!


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## SilverFox (Dec 28, 2005)

Hello Bill,

Thanks for catching that. I have edited it and it should be correct now.

I usually use test mode more than any other mode, but I have been using the discharge mode as of lately with new cells. You are right, I was stuck in the discharge mode state of mind... 

Tom


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## Mike abcd (Dec 29, 2005)

SilverFox said:


> Hello TrueBlue,
> 
> When you get your new cells, I would suggest you follow the following procedure for charging them.
> 
> ...



Based on a number of recent reports of charging failures at 200 mA, I'd suggest using at least the 500 mAH rate. The magnitude of the -delta V used for charge termination will be smaller and harder to detect at lower charge rates. Recent reports suggest it's problematic on the BC-900.

If you use 200 mAH, make sure the BC-900 shows the cells as "Full" after 14 hours for 2500 mAH cells. If not, it's probably failed to detect the "full charge" -delta V and will damage the cells. Leaving them in for the full 18 hours to be topped off with a "trickle" charge is ok as long as that happens.

I've settled on the 700 mA rate for charging 2500 mAH Energizers. It seems to keep them a bit cooler than the 1000 mA rate and I still get very consistent charging to very near full capacity.

Mike


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## SilverFox (Dec 29, 2005)

Hello Mike,

I was suggesting charging at 200 mA for the first charge and not relying on the charger to terminate the charge. That is why we are looking at the clock and shutting thing down after 18 hours. If we manually shut down the charge based on time, we don't care if the charger sees the end of charge signal or not.

Your system will work on subsequent charge cycles.

I came up with 18 hours charge time based on the assumption that they may only be 2600 mAh cells in spite of their 2800 mAh label. With NiMh cells, you loose about 40% while charging. If we take 2600 and multiply it by 1.4 we get 3640. Then we take the 3640 and divide that by 200 and I come up with 18 hours plus a little extra. If the cells are really 2800 mAh capacity, the charge time would be close to 19.5 hours.

Tom


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## MattK (Dec 29, 2005)

I just wanted to add my 02.

I'm in the battery business and perhaps I can bring some clarity to this.

Pretty much any claim over 2300mah is bunk. I've tested dozens of brands on a Cadex analyzer and spoken to probably 20 manufacturers. No one now is currently producing a cell that can attain over 2300mah at a realistic charge rate. Most 2300mah capacity claims are based on a charge rate of .05 (over 48hrs) and discharge rate of .2C

The only way to attain these wildly exagerated numbers is to charge AND discharge at unrealistically rates which can only be done on a fairly sophisticated analyzer rig.

There is no such thing as a 2800mah nimh AA battery. 

In my experience there's no such thing as a 2500mah cell either - not from Sanyo, Maha or any of the other so called 'premium brands'. Though one can screw with charge/discharge rates enough to achieve this capacity it's not an honest number.

Sadly there is and has been rampant capacity inflation in the industry for a few years now. The problem has only compounded as each company seeks to outdo eachother through 'label upgrades' because they count on consumers not knowing or caring enough to check. This goes for the big guys too.

I repeat - the only way to attain these capacitities is with ultra low rate charging/discharging in a very cool environment. 

Most consumers charge their cells at 300-1000mah and will be lucky to see 2000mah at best.

The only domestic US NiMh plant I'm aware of is the old Dynacharge factory bought by Duracell a few years ago - I'm not sure if it's still producing batteries.

/Matt


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## wptski (Dec 29, 2005)

MattK:

Since you appear to be new to this forum, you might want to look at: Ni-MH Battery Shoot Out and scroll down to the 2500mAh Energizer cell. Look at the capacity of these cells at 1A, 2A and even 3A! I think that SiverFox will stand behind his tests too!!


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## Mike abcd (Dec 29, 2005)

SilverFox said:


> Hello Mike,
> ..
> 
> I came up with 18 hours charge time based on the assumption that they may only be 2600 mAh cells in spite of their 2800 mAh label. With NiMh cells, you loose about 40% while charging. If we take 2600 and multiply it by 1.4 we get 3640. Then we take the 3640 and divide that by 200 and I come up with 18 hours plus a little extra. If the cells are really 2800 mAh capacity, the charge time would be close to 19.5 hours.
> ...



Tom,

The Duracell docs say that maximum capacity is reached with 150% of C charge input but that maximum life is affected. 
"higher capacity levels are achieved with a 150
percent charge input, but at the expense of cycle life;
long cycle life is attained with a 105 to 110 percent
charge input, albeit with slightly lower capacity"

That combined with my observations of my BC-900 make me worry about pumping 140% of capacity into cells for conditioning. With 2500 mAH Energizers (Sanyo), at 700 mA, it reports about 2.7 AH charge input and about 2.8 AH @ 1000 mA rate.

The cells will be able to deal with an overcharge better at the lower rate but it still leaves me concerned.

Do you have any references supporting conditioning with 140% of C charge at a low rate. I'd be very interested in them. I suspect I know more than the average consumer about this but also realize there's an awful lot more I have to learn.

I'd also like to thank you for all your efforts evaluating chargers and batteries. Your work on this web site is by far the best compilation of real world testing I've run across and is deeply appreciated.

Mike


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## John N (Dec 29, 2005)

Bill, I'm not sure if you are agreeing with Matt or disagreeing with him. But in either case, I don't see Matt's claims at odds with SilverFox's tests. Especially if you consider the Energizer 2500 is one of the best cells tested and SilverFox's charging methology is pretty sophisticated, and even then, the best result is 2.236 Ah vs the rated 2500. 



wptski said:


> look at: Ni-MH Battery Shoot Out and scroll down to the 2500mAh Energizer cell. Look at the capacity of these cells at 1A, 2A and even 3A! I think that SiverFox will stand behind his tests too!!





MattK said:


> Most consumers charge their cells at 300-1000mah and will be lucky to see 2000mah at best.



Summary of SilverFox's Energizer AA 2500 tests:
1A test = 2.230 Ah
2A test = 2.236 Ah
3A test = 2.110 Ah
5A test = 2.163 Ah

-john


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## hookoo (Dec 29, 2005)

I just revisited that thread. Correct me if I am wrong, I do not see any of the AA testing over 2300mah.


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## John N (Dec 29, 2005)

Pretty much. Here is a summary of some of the top performers. I selected a battery for the "top performers" list if it's 5 Amp test result was =>2.0 Ah. If you look through them, it looks like the largest absolute number is 2.350 Ah, provided by the Sanyo Industrial AA 2500 with the 1 Amp test.

While I guess that is technically over 2300, it certainly isn't by much.

Forgive any typoes. Thanks again to Tom/SilverFox for providing this great data.

BTW, I think the main thing I want to know about these "2800 mah" cells is if it can beat the five batteries listed here. 

-john


Energizer AA 2500
Test/Amp |000.5|001.0|002.0|003.0|005.0|
ResultsAh |2.193|2.230|2.236|2.210|2.163|

Sanyo Industrial AA 2500
Test/Amp |000.5|001.0|002.0|003.0|005.0|
ResultsAh |2.322|2.350|2.263|2.207|2.192|

AccuPower AA 2600
Test/Amp |000.5|001.0|002.0|003.0|005.0|
ResultsAh |2.297|2.316|2.263|2.194|2.085|

Titanium AA 2600
Test/Amp |000.5|001.0|002.0|003.0|005.0|
ResultsAh |-n/a-|2.313|2.245|2.176|2.121|

Vapextech AA 2500
Test/Amp |000.5|001.0|002.0|003.0|005.0|
ResultsAh |-n/a-|2.195|2.147|2.034|2.049|


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## wptski (Dec 29, 2005)

JohnN:

I wasn't agreeing with MattK because he said that you'd be lucky to see 2000mAh but it's the cells that are rated way over 2000mAh that test that high.

The Titanium 2000mAh tests show a results that are pretty much equal to their rating.


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## SilverFox (Dec 30, 2005)

Hello Matt,

Welcome to CPF.

I am afraid that as much as we hope for a 2800 mAh cell, actual testing pretty much supports just what you are saying. There are only a couple of cells that I have tested that tested at or slightly over 2300 mAh. Most of them are closer to 2000 mAh.

I will have to play around with some 2500 mAh cells and see if I can duplicate the results from the data sheets. I was able to get a good correlation with 2000 mAh cells by testing them right off the charger and at a low rate. I have not tried that with the 2500 mAh cells.

I wonder if the people that label the larger spot lights are also consulted on labeling the batteries. A 1.5 million candlepower light would be even more impressive if it was powered by a 1.5 million mAh battery... 

Tom


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## wptski (Dec 30, 2005)

Tom:

The point is that MattK stated that you'd be lucky to get 2000mAh but your detailed tests prove that you can higher capacities but that's with cells rated at 2300mAh or higher. The Titanium 2000mAh tests results are at or slightly above rated capacity.


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## SilverFox (Dec 30, 2005)

Hello Mike,

I just happened to be doing some studying on the GP site, and the 140% stuck in my mind.

There seems to be some differences of opinion in what is optimal for a timed charge at a low rate. Sanyo suggests that the industry standard is to charge at 0.1C for 16 hours. GP reports their capacities using a 14 hour charge at 0.1C Duracell suggests 120% accompanied by a thermal cut off of 140 F.

I have used 14 hours for quite a while and have had no problems with it.

However, the information that Matt brought forth indicates that a maximum capacity would probably be in the 2300 mAh range. That would require a slight reduction in charge time, and a reworking of the numbers.

Tom


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## TrueBlue (Dec 30, 2005)

I’m still listening and taking notes. I’m not worried about testing the batteries until they arrive at my doorstep. I want the batteries in hand first. When the batteries get in my house I’ll start think about testing them.

My first thought it to charge up the batteries. Then I’ll have fun conditioning the cells. I’ll use my Vivitar 285 camera flash to drain them.

The camera flash should drive my neighbors nuts. I can drain batteries quick with the flashes. Charge and flash, charge and flash. Popping the flash will make the neighbors think the New Year night came early. They will think I’m nuts. They might think I’m nuts AND New Year night came early. I’m already nuts.

A side by side test next to Energizer 2500mA batteries sounds reasonable. Every battery has a different capacity even if they come from the same batch. The test is a quick and dirty test to see if the Tamiya batteries are in the range of 2800mA. Plus or minus 15% capacity would be reasonable. So the range of the cell should be between 2350 (believable) to 3220mA (highly unlikely.)

I’ll drain the batteries one more time then put them in the BC-900, set the mode to test at 500 or 700 mAh and see what the capacity is. I might test twice. Once at 700mAh to get fast answers to post. Then another test at 500mAh to see if the answers are reliable. I might do the 700mAh test twice. In that case I would switch the batteries in the bays to make sure each bay is working properly.

To keep the tested batteries cool and more accurate I would think a charge of 500 to 700mAh is a good compromise. I have a temperature probe so I can monitor the temperature.


It seems NiMH batteries do not have much capacity over 2300mAh. The batteries seem to have more capacity if you use them hot off a charger. The additional mAh the battery makers hype seems to sag to 2300mAh within a day.


None of this testing happens until I get the batteries in the mail.


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## wptski (Dec 30, 2005)

TrueBlue:

I forget the model number but I have a old Sunpak handle mount, I think that it's a guide number 120. Ever put your hand in front of the lense while you hit the test button? Feel the heat! :wow:


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## John N (Dec 30, 2005)

TrueBlue said:


> A side by side test next to Energizer 2500mA batteries sounds reasonable.



Thanks, that would be great!

-john


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## TrueBlue (Dec 30, 2005)

wptski said:


> TrueBlue:
> 
> I forget the model number but I have a old Sunpak handle mount, I think that it's a guide number 120. Ever put your hand in front of the lense while you hit the test button? Feel the heat! :wow:



Try having the flash next to your ear when it pops at full power. FEEL THE HEAT!


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## MattK (Dec 30, 2005)

Hi guys and thanks for the welcome 

I actually wrote a brief into about myself last week https://www.candlepowerforums.com/posts/1205720&postcount=9

I think SilverFox's shootout largely proves my point. You're also frankly counting, and no disrespect meant, on the accuracy of his methodology and testing device.

Ambient temperature's need to be recorded and stable in order to have any consistency between tests and while I'm a huge fan of the Vanson BC1-HU as a quality, reliable and affordable charger there's simply too many variables not accounted for.

When were the cells manufactured in relation to the test? How many cycles had they gone through prior to testing? Of these previous cycling how was that cycling done? How many cells from each brand were tested? What was the ambient temperature? How many cells were in the charger when each cell was charged and discharged? What was the interval between the cells coming off of the charger and the test being performed? etc...

There's a huge amount of variables and frankly batteries are much like LED's - for every group there are some that will come out better and some that will come out worse - as a matter of fact batteries from 2100-2300 all come off of the same production line and are sorted afterwards.

It's also a given IMO that batteries supplied by sellers and manufacturers are the freshest possible cells that have been cycled an optimal amount of times using an optimal method. It's certainly what I'd do were I supplying cells to be tested.

I don't want to get into a pissing contest with anyone I'm just stating the facts as I know them. I think Silverfox's shootout is valuable and a great contribution but must be taken with a grain of salt given the variables unaccounted for.

We'd all like to have 3000mah AA cells but given the current state of technology no manufacturer is attaining what I consider a true 2500mah never mind anything higher. That said, NiMh technology has improved vastly in the last few years and we've seen tremendous consumer acceptace of rechargables which I think we can all agree is a great stride forward from an environmental and economic standpoint. Also, the simply enormous competition and, frankly, the overproduction of AA and AAA cells has resulted in an EXTREMELY consumer friendly environment. 

Here's a data sheet that I think you'll find fairly informative; this is pretty typical.
http://www.shorelinemarket.com/ebayimages/batteries/batteryspecs.jpg

Happy New Year!

/Matt


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## TrueBlue (Dec 30, 2005)

I am the worst laboratory on this planet.

I do not have a research center dedicated to battery testing. There is no crate of battery samples to average. There are only 4 Tamiya battery, consumer grade, samples. There are no walls of equipment in a test room. My test center is very poor.

Reviewers get free samples. Reviewers get ‘select’ reviewer grade parts to review. The samples are not necessarily real world samples. Many products are free for reviewers to keep. I have seen reviewers get better than consumer grade products.

My battery samples, mAh test numbers, will probably be lower than any reviewer grade test numbers.

My small sample of Tamiya batteries are bought ‘off the street.’ The money came from my wallet. I told the seller of the batteries that I am going to test the batteries after I knew he shipped them. I wanted consumer grade batteries to test. I am going to test batteries that CPF member would end up buying.

Like other CPF members, I am an end user. We would like to see what a real world 2800mAh Tamiya battery mAh numbers are. We would like to see if the batteries are a waste of money. We are open minded enough to see if the batteries could be a revolutionary product.

With my humble BC-900 charger and temperature probe we can generate real world numbers. I don’t have the best test center. My numbers wouldn’t be the most accurate in the world. It sure beats guessing. In the end I will try the Tamiya versus Energizer battery in a real light. I will graph and post a graph of the batteries as they run in a light. We want a real world test.

I will simply generate the numbers between known Energizer 2500mAh batteries and the test batteries.

CPF members can join in and figure out the results of the numbers.

Please don’t expect the most accurate numbers from me. If any CPF member has a much better test center they are welcome to test the Tamiya batteries. Until then, the test results from the worst laboratory in the world are better than buying batteries blindly.


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## MattK (Dec 30, 2005)

LOL - well done.

/Matt


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## Mike abcd (Dec 30, 2005)

Hi Tom,

I took a quick look through the Sanyo NiMH doc. It seems to state that the standard for capacity tests is a 16 hour .1C charge but I can't find anything that advises using that charge method. It just seems designed to max out the cell capacity for testing purposes although possibly at the expense of lifetime. It's interesting that their data on capacity vs # of cycles doesn't appear to use that method. Sanyo, like Duracell seems to generally advise against slow charging.

I generally start by discharging new cells and find some that have appreciable initial charge. I still doubt that a single long slow charge cycle would have any appreciable impact.

I haven't looked at the GP data before but I will when I get a chance.

I've been very convinced of the value of conditioning cells before putting them to normal use in packs by large differences in capacity over the first couple/few cycles. I suspect most of that is due to early charge termination due to their "eratic" voltage profiles when new. I'm very interested in any data on methods that improve capacity or cycles and appreciate the info.

Mike


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## SilverFox (Dec 31, 2005)

Hello Matt,

You have brought up some vary important questions. You will find that most of your questions have already been brought up and discussed in the Shoot Out thread.

However, there are a couple that have not been addressed…

I have no idea of the manufacturing date of the cells tested. Since almost all of those tested were provided by members of CPF and returned to them, I have no way of checking them out. I would guess that most of the cells were less than 3 years old. Several people sent me new cells in the package, but others sent me cells that they had been using for awhile. I had some 3 year old cells that were included in the testing.

I would guess that the number of cycles on the cells varied from 5 to less than 100. While I have some cells that are approaching 200 cycles, I don’t think most people that supplied me with cells to test use their cells as much as I do.

I am not sure what your question about how many cells were in the charger means. All charging was done with an independent channel charger and the cells were rotated from slot to slot to minimize any charging variations.

An interesting story comes to mind when discussing the accuracy of the testing. I was one of the Beta testers for the CBA unit. There were a few problems with the unit when it was first released, but those issues got worked out. Prior to publishing the NiMh Shoot Out data, I participated in a series of round robin tests with a friend who had access to a Cadex 7200 analyzer. I was very pleased with the results. The difference in our results was about 1%. My results were always lower. We tested at 0.5 amps and 1.0 amps.

I have also compared results to tests done on the Competition Electronics Turbo 35 GFX unit. Once again there was good agreement, and once again my results were lower.

When several people purchased BC-900 units, we compared the results. I found a very close correlation when I tested in a similar manner as the BC-900 uses.

All of these comparisons make me feel comfortable with the results I am presenting. If anything, I am a bit conservative. The biggest problem with this whole round of testing is the lack of samples to test. In spite of that, I believe there is a lot of valuable information that has been presented. 

Tom


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## SilverFox (Dec 31, 2005)

Hello Mike,

I am sorry, but I don't have any long term cycle life results. I have been keeping track of cycles on a set of test cells, but am only up to about 200 cycles on them. I have pushed them quite hard and have been surprised that the capacity is remaining about the same as when I first tested them.

If I ever make it to 500 cycles, I will let you know...  

Tom


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## paulr (Dec 31, 2005)

I bought a bunch of Sanyo HR-3U industrial (green label) 2500 mah cells from batterystation earlier this year (April 2005) and they had a manufacturing date (12/04) stamped on them. They also had a fair amount of charge when I got them.

I've been using the bc-900 discharge/test function to measure capacity and found the 2500 mah cells all test a little bit below rated capacity. Of course that's a "hot off charger" measurement and the Cedex (etc.) measurements are probably more realistic.


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## wptski (Jan 2, 2006)

balazer said:


> I think I read it in the manual.


balazer:

I know where you seen 3000mAh limit now! It's printed right on the bottom of the BC-900. No mention in the manual either.


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## SilverFox (Jan 4, 2006)

In an effort to better understand Matt’s observations, I did some testing on some new Powerizer 2500 mAh cells. They, in the fine print, are rated at a minimum of 2300 mAh. I am not sure why they have 2500 mAh on them… Perhaps marketing has something to do with it. 



MattK said:


> Pretty much any claim over 2300mah is bunk. I've tested dozens of brands on a Cadex analyzer and spoken to probably 20 manufacturers. No one now is currently producing a cell that can attain over 2300mah at a realistic charge rate. Most 2300mah capacity claims are based on a charge rate of .05 (over 48hrs) and discharge rate of .2C
> 
> The only way to attain these wildly exagerated numbers is to charge AND discharge at unrealistically rates which can only be done on a fairly sophisticated analyzer rig.



The testing was done on 4 cells. The cells are brand new and testing was done at 68 F.

The charge rate was 1C (2500 mA), the discharge rate was 0.2C (500 mA), and I discharged down to 0.9 V.

Test cycle 12 resulted in a capacity of 2381 mAh,
Test cycle 13 resulted in a capacity of 2385 mAh,
Test cycle 14 resulted in a capacity of 2387 mAh.

While this is not quite up to the 2500 mAh rating, it is over the 2300 mAh capacity level. Charging at 1C is a very realistic charge rate, and discharging at 0.2C is the standard discharge rate the industry uses for rating capacity.

It looks like the capacity to beat is 2400 mAh…

Tom


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## TrueBlue (Jan 4, 2006)

The Ebay win is here from Hong Kong to California. 9 days air mail in a white envelope is four Tamiya 2800mAh NiMH batteries.

In the front the batteries says:

Mini 4WD
Tamiya
NiMH battery (N-3US)
2800
Rechargeable
Tamiya Plastic Model Co.

In the back with a lot of Japanese language is the English that says:

Made in Japan







Here is a little information:

Tamiya 2800mAh batteries x 4, weight= 4 oz./115g
Per cell= 1 oz./28.75g per cell

Energizer 2500mAh batteries x 4, weight= 4.1 oz./117g
Per cell= 1.025 oz./29.25g per cell



I am conditioning the batteries now. The Energizer 15 minute charger powered the batteries up and the Vivitar 285 camera flash brought them down. The cells are gaining capacity with each charge and discharge. The flash only got 10 ‘pops’ the first charge. The flash was set for full power. The second battery charge gave the flash 27 pops.

Now the La Crosse charger is refreshing the batteries. 500mA discharge and 1000mA charge.

After the refresh cycles I will use my flash to bring the power down in the batteries. I will use the La Crosse charger set for 500mAh charge and 250mAh discharge to see if the Tamiya battery capacity will stop at. I’ve got a tested capacity Energizer 2500mAh battery that I will use to see how close the battery capacities are.

This is not the most perfect test. My samples are limited to four batteries. If I had a hundred Tamiya batteries I could get a much better idea what the average capacities of the 2800mAh batteries are.


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## VidPro (Jan 5, 2006)

no more bets please, Spin that wheel


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## TrueBlue (Jan 5, 2006)

I am still getting the batteries in fighting condition. Charge, discharge and repeat.

When I took the Tamiya batteries out of the package, the first thing I did was a voltage check. The numbers scared me.

Multimeter voltage measurement:

Battery # 1 Voltage- 1.01V
Battery # 2 Voltage- 0.01V
Battery # 3 Voltage- 0.00V
Battery # 4 Voltage- 0.88V

La Crosse charger voltage measurement:

Battery # 1 Voltage- 1.00V
Battery # 2 Voltage- 0.00V
Battery # 3 Voltage- 0.00V
Battery # 4 Voltage- 0.98V

I guess Tamiya doesn’t believe in putting a stabilizing charge on their batteries. The batteries after the first charge seem to be holding their charge. They are working.

I’ve marked the batteries. I want to see if #2 and #3 batteries die prematurely because of the initial low voltage.


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## wptski (Jan 5, 2006)

TrueBlue:

Oh Boy! If it's not under lab conditions the "Testing Policeman" will pull you over!


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## balazer (Jan 5, 2006)

TrueBlue said:


> I guess Tamiya doesn’t believe in putting a stabilizing charge on their batteries.


Unless these batteries are special, it wouldn't matter what charge state Tamiya shipped the batteries in because they'd self discharge anyway. It does no harm to the battery to be left in a zero-charge state.


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## missionaryman (Jan 5, 2006)




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## wptski (Jan 5, 2006)

balazer said:


> Unless these batteries are special, it wouldn't matter what charge state Tamiya shipped the batteries in because they'd self discharge anyway. It does no harm to the battery to be left in a zero-charge state.


balazer:

I should digup my thread about about the MAHA PowerEx 1800/2000mAh that were neglected by me. Brand new in plastic cases that were still wrapped, some leaked, others wouldn't charge on any "smart" charger or a special forming charger. Some that survived had limited capacity. Twelve 1800mAh and two of the 2000mAh were chucked.

I know I've read that too, it doesn't hurt them! I guess that you can't believe all you read!


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## bcwang (Jan 5, 2006)

I guess I should mention I got some of these tamiya 2800mah batteries from hong kong around dec of 2004. They were obviously fake as 2500mah just came out from the big guys, and they were cheap to buy, maybe $1 each. Got back and tested them on my bc900 and capacity never exceeded 1600mah. I wasn't expecting them to be real. They also had the made in japan wrapper and look exactly like the picture posted here. Asia is full of knockoff products. They were obviously using the tamiya name and high mah rating to sell them. But everyone knows their fake when they come in a shrink wrap with no real packaging and costs less than the GP and Sanyo cells selling at the same store.


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## TrueBlue (Jan 6, 2006)

Testing...testing.


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## hookoo (Jan 6, 2006)




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## TrueBlue (Jan 6, 2006)

Worse than disappointing is my first thought. Second, third and forth thoughts:

This is what Tamiya says is 2800mAh cells.
What were they smoking?
What are they dreaming?



Results of the FIRST TEST.

500mAh charge & 250mA discharge. My first test result.

Battery #1= 1130mAh
Battery #2= 1244mAh
Battery #3= 1338mAh
Battery #4= 1128mAh


This is not even close to have the claimed capacity. If these batteries were for ‘Mini 4WD’ then the poor RC car could run 80 feet with a push, downhill run and a fair wind. It would not drive back. You will have to go get the car.

To simplify the above. So far these are terrible cells.

I have 5 year old Olympus NiMH batteries that still hold 1500mAh. I would use my Oly cells before I use these new Tamiya cells.



I’ll give the Tamiya cells a second chance to redeem themselves. I’ll use a known quantity with the next test.

I’m going to do the same test but I will take out the lowest mAh Tamiya battery, #4. It will be replaced with a known Energizer 2500mAh battery. The Energizer battery is a tested cell. It measures 2500mAh on the La Crosse charger.

Remember that I only have four of these Tamiya batteries to sample. Maybe another batch of batteries would be have more capacity?

I doubt it.


Who wins the bet so far?


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## VidPro (Jan 6, 2006)

figures, thanks for saving me 8$.


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## john2551 (Jan 6, 2006)

William,

Thanks for the "heads up" & test on these garbage cells. I guess i'll just stick to the Energizer 2500 AAs.

Regards,

John


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## SilverFox (Jan 6, 2006)

Hello TrueBlue,

Interesting... 

I just finished a series of tests similar to what I reported on in post #87 on some AmondoTech Titanium 2600 mAh cells. Charging at 2.5 amps and discharge at 0.5 amps, I am getting 2496 mAh. I guess this means that the new mark to beat is 2500 mAh.

Your cells are going to need a lot of help to even come close to that... 

I should point out that in order to get the maximum capacity from a cell, you need to start the discharge test immediately upon the finish of the charge cycle. When I show results in the Battery Shoot Out threads, I let the cells rest for a while after charging. This allows the excess surface charge to bleed off, and I feel it gives a more realistic value. If you top your cells up just before using your lights, you will get better performance that what I am reporting.

Tom


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## TrueBlue (Jan 6, 2006)

Testing the Tamiya batteries the second time did not show an improvement in capacity. I didn’t expect the batteries to improve.

I tested the unknown batteries with a known Energizer 2500mA battery. The Energizer was in bay #4.

Results of the FIRST TEST.

500mAh charge & 250mA discharge. My first test result.

Battery #1= 1130mAh
Battery #2= 1244mAh
Battery #3= 1338mAh
Battery #4= 1128mAh


Results of the SECOND TEST.

500mAh charge & 250mA discharge.

Tamiya battery #1= 1017mAh
Tamiya battery #2= 1264mAh
Tamiya battery #3= 1406mAh

Energizer battery #4= 2510mAh


I really don’t see any reason to test the Tamiya batteries any more. The Tamiya batteries might gain a slightly more capacity with use. They will not gain 228% capacity to hold 2800mAh of power. I’m finished.

Does anyone want to email Tamiya and ask them who tested the company’s batteries? Maybe someone could ask them how the came to the conclusion these batteries are 2800mAh capacity.

The Tamiya 2800mAh batteries are the worst out of the box NiMH batteries I’ve ever tested.


----------



## SilverFox (Jan 6, 2006)

Hello TrueBlue,

I can only suggest one additional test, but it is very time consuming and you have to keep an eye on it.

Put the cells in the BC-900 and select the discharge mode. This will discharge them at 100 mA and then charge them at 200 mA. The discharge should take about 14 hours, and the charge about 8 hours. You need to watch the charge side because the charger may not see and end of charge signal. when the voltage reads around 1.44 volts and the cells start to warm up, shut things down.

Then do another test mode.

If you see a significant jump in capacity, it could mean that those cells have been sitting around for quite a while. I still don't think they will come close to your Energizer cells, but it may be interesting to try...

Tom


----------



## john2551 (Jan 6, 2006)

Tom, 

You are saying that amondo's titanium 2600 are the best @ 2496mah. But William just tested an Energizer 2500 that tested @ 2510. Am i splitting hairs here or are those numbers so close that it would be pretty much a tie score?

John


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## TrueBlue (Jan 6, 2006)

The numbers are real close. You could test a cell ten times and you would get slightly different numbers each time.

Keep your batteries. The capacity is equal to the Energizer battery.


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## SilverFox (Jan 6, 2006)

Hello John,

If your light draws 1.0 amps, the difference amounts to about 50 seconds of run time. I think that is pretty close to splitting hairs...

Tom


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## paulr (Jan 6, 2006)

I think you need to try the Lacrosse in the Discharge/test mode, 500 ma charge, 250 discharge. That discharges and recharges the batteries repeatedly until the measured discharge capacity stops increasing, typically 5 or so cycles, so it can take about 2 days. It's quite normal to get a significant increase by doing that. Just leave the setup alone and check on it next week.


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## TrueBlue (Jan 6, 2006)

Thanks, paulr. That is a good idea. I'll give it a try. See you all in around two days.


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## paulr (Jan 6, 2006)

TrueBlue said:


> Does anyone want to email Tamiya and ask them who tested the company’s batteries? Maybe someone could ask them how the came to the conclusion these batteries are 2800mAh capacity.


I don't think there is any mystery about this. They sell more batteries if they're labelled 2800 mah, so they must be 2800 mah, because that's where the money is, measurements be damned.


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## BatteryCharger (Jan 6, 2006)

I sure hope whoever has bought these batteries doesn't let the seller get away with good feedback....


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## balazer (Jan 8, 2006)

I'd second the suggestion to use the BC-900's refresh mode, combined with some extended trickle charging in-between. In tests on my Duracell 2300 mAh cells, I found that 4-5 refresh cycles only got the cells up to 60% before the capacity stabalized and the refresh process stopped. It took some overnight trickle charging and another 4-5 refresh cycles before the capacity neared 2300 mAh.

Not that it would really matter, since these cells are most likely knock-offs.


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## balazer (Jan 8, 2006)

wptski said:


> balazer:
> 
> I should digup my thread about about the MAHA PowerEx 1800/2000mAh that were neglected by me. Brand new in plastic cases that were still wrapped, some leaked, others wouldn't charge on any "smart" charger or a special forming charger. Some that survived had limited capacity. Twelve 1800mAh and two of the 2000mAh were chucked.
> 
> I know I've read that too, it doesn't hurt them! I guess that you can't believe all you read!


Do you know that the cells wouldn't have failed if they weren't neglected?

It might depend on the cells. I have some NiMH cells that have sat dead for >5 years and charge still charge up to full capacity.


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## missionaryman (Jan 8, 2006)

I don't know that I'd bother re-testing them as I can't see them picking up another 1500 - 1800mah. I visited my local Olympic Batteries 
(not - so)superstore and spoke to the rep about these and he explained that there is NO legislation in China to police the accuracy of these claims so they could legally put 4000mah on AAA's and get away with it. He might not be right but from this test I might believe him.

I emailed a Chinese manufacturer (who I won't name in case no body buys a 15million candlepower spotlight from northen tool again...) about this same issue and the response was "we don't use the same method of measure in our country as you do in yours" then they never spoke to me again. So no offence intejded to anyone who may be Chinese but I wouldn't count on the accuracy of these claims - testing and common sense is the best insurance. 
Though I must say it's very dissapointing coming from someone as trusted as Tamiya.


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## John N (Jan 8, 2006)

Do we know for sure that these are direct from the mfg. or counterfiit?

-john


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## wptski (Jan 8, 2006)

balazer said:


> Do you know that the cells wouldn't have failed if they weren't neglected?
> 
> It might depend on the cells. I have some NiMH cells that have sat dead for >5 years and charge still charge up to full capacity.


balazer:

When you read a paper on Ni-MH chemistry, it has nothing to do with brand name although it may be written by a brand name company. You can read about how to handle/care for your cells but that doesn't always work as I have found out.

BTW: What brand are you refering to?


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## balazer (Jan 8, 2006)

I don't remember what brand cells I had. They had a plain green sleeve.


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## VidPro (Jan 8, 2006)

"""Does anyone want to email Tamiya and ask them who tested the company’s batteries? Maybe someone could ask them how the came to the conclusion these batteries are 2800mAh capacity."""

it is more likly that the company IF it is spelled the same , should be e-mailed and told that thier trademark is bing infringed, because knowing e-bay and SOME china sellers, that is what is likely.
e-bay also can be informed, and they will pull thise particular auctions, but without some sort of basis for e-bay to know what is going on, they wont pull anything, except more money for listings .

on the other hand, it might be time for a CHEER, to the online distributers that are well known, for thier more realistic specs of the things they sell.


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## CroMAGnet (Jan 9, 2006)

I just saw the same batteries at an RC hobby store down the street but they were labled 1000mAh.


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## MattK (Jan 10, 2006)

A few FYI's:

I'm farily certain that the Energizer 2500's are made by Sanyo.

Sanyo just showed 2700mah cells at CES last week. Per my previus remarks I'd be surprised to see them attain over 2300mah never mind 2500mah never mind 270mmah...that said I'm willing to bet they'll be the best product on the market.

Oh and I sincerely doubt those cells are really Tamiya - I say counterfeit.

Tom, I wrote you a lengthy reply last week but the forum crapped out on me and I lost the post and didn't have the heart to type it all again. :/

Best,

/Matt


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## BatteryCharger (Jan 10, 2006)

MattK said:


> Sanyo just showed 2700mah cells at CES last week. Per my previus remarks I'd be surprised to see them attain over 2300mah never mind 2500mah never mind 270mmah...



Well, the 2500s show between 2300 and 2500 mah depending on who's doing the test, so I'd expect Sanyo 2700s to be at least 2500. I think the Sanyos are about the only batteries that have touched the label capacity in real life tests...


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## VidPro (Jan 15, 2006)

update
e-bay pulled the auctions for them

""Our records show that you were a bidder on this item. We recently removed this listing and have suspended the seller's trading privileges.""

good ridance.


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