# NIZN VERSUS NIMH



## 357mag1 (Jan 5, 2010)

I bought some of those 1.6V Power Genix batteries just to see how they would work compared to the Rayovac 4.0 LSD batteries I have. This is far from a scientific test but gives one a rough idea how these batteries compare. 

The Power Genix batteries come off the charger right around 1.87 volts and the Rayovacs are around 1.45 volts as read on my trusty Fluke multimeter. I used batteries that had been charged about 10 days ago but they were both charged on the same day. The Rayovac I used measured 1.36 volts and the Power Genix measured 1.82 volts.

The flashlight used was a Quark AA Tatical R2 set to the high mode which is suppose to give 90 lumens out the front with a single AA battery. I'm impressed with the little light as it easily matches my Surefire 6P LED in output and has a warmer beam. 

If you are wondering if the light is brighter with the Power Genix battery it is but not by much.

I started with the Power Genix battery and turned the Quark on at it's Max setting and let it set on the end table while watching Football this past Sunday. According to the literature with the light it should last 1.2 hours or 72 minutes but it doesn't say with what type of battery. The light started to fade at 97 minutes and was fading fairly fast. The battery measured 1.45 volts when I removed it.

I let the light cool down for 30 minutes, it only got mildly warm to begin with. It was cool to the touch when I started with the Rayovac. The Rayovac started to dim at the 87 minute mark and was fading fast.

Fairly impressed with both batteries. When starting I thought if they reached an hour I would be doing good. The Rayovac seemed to be fading faster when it started but neither battery was going to last long on Max. I didn't want to run them on a lower setting until they died completely as I understand that can shorten the battery life drastically.

So are the Power Genix batteries worth the expense of an extra charger and the hassle of tracking a different set/type of batteries. Probably not for flashlight use but they do seem to work as advertised and if you have something that needs the extra voltage they may be the ticket. Just be careful because as I stated earlier they come out of the charger at 1.87 volts or there about and that is higher than the Energizer Lithiums.


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## Conte (Jan 5, 2010)

Hmm, you gained 10 mins.

Now the question is, what is the mAh rating of the 2 diff batteries ?

I've been meaning to try those NiZN Batteries, but they seem difficult for me to get.
Where did you get yours and how much ?


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## 357mag1 (Jan 6, 2010)

The Power Genix are rated at 2500 mwh since wattage is a power reading. If you consider the Rayovacs are 1.2 volts and multiply that by their rated 2100 mah you arrive at 2550 mwh. Meaning they should be roughly equivalent.
I bought them off Amazon for around $25 which included four batteries and a charger. For an extra $20 I got eight more batteries and free shipping.


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## Conte (Jan 6, 2010)

Hmm, then the 10 min gain much be cause the batteries hold their voltage longer despite the capacity.

I've never bought anything from amazon before. I think my GF has, perhaps I'll ask her about it.


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## Rexlion (Jan 6, 2010)

NiZn cells sound interesting. I immediately thought of my Canon A series cameras, which seem very finicky about their AA's. So I checked Canon's website for mention of NiZn: nothing. Then I wrote their customer service and asked it NiZn would be ok. They replied with a stock, cut & paste type of answer that did not answer my question. I should have known they would be too lazy to give a real answer... :shakehead I haven't decided whether to chance it or not.


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## turboBB (Jan 7, 2010)

357, thx for posting this. I had been considering alternatives to Li-Ion 14500's (protected or not, just not comfortable carrying Li-Ion spares).

I was debating getting Eneloops but decided to give these a shot instead. Did the same thing and got the charger + 4 AA's as well as the 8 AA's. Will post back with my feedback once I get 'em.

Cheers,
Tim


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## Phaserburn (Jan 7, 2010)

Very cool! Great for lights that need the higher voltage for max performance. Might have to get me some... anyone know the best source for these?


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## Conan (Jan 7, 2010)

Rexlion said:


> NiZn cells sound interesting. I immediately thought of my Canon A series cameras, which seem very finicky about their AA's. So I checked Canon's website for mention of NiZn: nothing. Then I wrote their customer service and asked it NiZn would be ok. They replied with a stock, cut & paste type of answer that did not answer my question. I should have known they would be too lazy to give a real answer... :shakehead I haven't decided whether to chance it or not.



If your camera runs better with AA Lithiums compared to Eneloops then it might be worth a shot to get the NiZn batteries. I bought them to power my Pentax DSLR's. There's no official blessing from Pentax to use these but my cameras would perform better with Lithiums so I decided to give it a try and they work good.


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## Conan (Jan 7, 2010)

Phaserburn said:


> Very cool! Great for lights that need the higher voltage for max performance. Might have to get me some... anyone know the best source for these?



I got mine from Amazon.com so that might be your best bet.


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## Christoph (Jan 7, 2010)

I bought a set and charger from Amazon as well. I am going to use them in single cell lights instead of protected AA li-ions.The first one I tried ran my RRT0 for 35 minutes on max min then went dim.the voltage was 1.3 and climbing as I checked it and it took a little over an hour to charge up again.It started out brighter than an eneloop.


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## BelliR6 (Jan 7, 2010)

Great post guys I have been thinking about running 3 of these in a Javelin w a NB SST 50 led....:shrug:


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## liketotallyrandom (Jan 8, 2010)

Has anyone compared the voltage under load with NiMH?


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## davidefromitaly (Jan 8, 2010)

that's great, the gain in efficiency thanks to the higher voltage make possible that a 1500mAh battery last longer and brighter than a 2000mAh 

and don't forget that a ni-zn cost less than a premium ni-mh (rayovak cost less of course) and the charger cost less than a premium ni-mh charger, with ni-zn we don't need any more complicated and unrealiable delta-V algorithms, the charge is always perfect like a li-ion or a SLA battery


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## turboBB (Jan 9, 2010)

Just got the charger and batteries today. There's definitely a noticeable difference in terms of brightness as seen by these shots of a Zebralight H501.

Control Shot:







Power Genix NiZn 2500 mWh @ 1.848v (left) POWEREX 2700 mAh NiMH @ 1.425v (right):







Canon S3 IS on M | 1/5" | 2.7f | Flash WB |

I'm not properly equipped to do proper run time tests so will defer to someone else for those but so far I'm impressed!

My RRT-0 is out for repairs currently but when I get it back, I'll take some additional shots.

Cheers,
Tim


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## Phaserburn (Jan 10, 2010)

I ordered some of these, just to play with. I think they'd be good for 2AA lights where the higher voltage would be closer to the led vf.


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## OpenGuy (Jan 10, 2010)

Conan said:


> If your camera runs better with AA Lithiums compared to Eneloops then it might be worth a shot to get the NiZn batteries. I bought them to power my Pentax DSLR's. There's no official blessing from Pentax to use these but my cameras would perform better with Lithiums so I decided to give it a try and they work good.



Be careful. I've seen reports of the NiZn batteries frying Pentax flashes.


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## Conan (Jan 10, 2010)

OpenGuy said:


> Be careful. I've seen reports of the NiZn batteries frying Pentax flashes.



I don't use them in my flash, only for the DSLR's.


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## Nite (Jan 28, 2010)

bought 8 of those 1.6V Power Genix batteries from amazon.

I want to use them in my electric jacket which uses a 3.7/4.2 volt, I suspect LiPoly gel pack. like the cell in the MacbookAir by apple.

the jacket also comes with a 6 AA battery holder if your in the woods and cant recharge.

NiMH wont work the voltage is too low to not use alkalines, till now, but will it be too much power?

more importantly *which charger is better you think for these cells? the Genix 1 hour charger or the genix 5 hour hour charger. both say they are fast chargers, both from amazon, both with 4 more cells. both with 4 bays*

edit-> based on 1.5 volts x 6 = 9 volts, I suspect this a 7.4 volt or so battery pack. SO if it works with 9 vollts from 6 alkies, will six times 1.87 = 11.22 and be too much? I better call the manufacturer



thanks


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## Conan (Jan 28, 2010)

The 1 hour charger is better but in reality it's a 2.5 hour charger as the batteries reach 80% in hour and gets trickle charged the rest of the way.


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## Mr Happy (Jan 28, 2010)

Nite said:


> NiMH wont work the voltage is too low to not use alkalines, till now, but will it be too much power?


This seems a little unusual. For heating devices or heavy current consumers it is typical for NiMH to work far, far better than alkalines. For example a hand held soldering iron I have kills alkalines but works like a charm on NiMH.

What is it that doesn't work about the jacket with NiMH? Does it give a low battery warning, or does it just not get warm?


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## 45/70 (Jan 28, 2010)

Nite said:


> NiMH wont work the voltage is too low to not use alkalines, till now, but will it be too much power?



A bit OT, but I've never come across a portable heating device like you describe, that was voltage dependent. These devices are purely current driven, and good NiMH/NiCd cells _always _work better than alkalines, because of this.

I suspect that the NiMH cells you are trying to use, are suffering from voltage depression (which means they can't deliver significant current, as well, except at very low rates) and just can't deliver enough power to create any heat.

Go ahead with your NiZN trial, but NiMH's should blow away alkalines in this type of device, if they are in good shape. You have to be careful not to over discharge NiMH cells in something like this, especially when they're in series, or you'll kill the cells. Recharge, well before they quit working.

In my experience with "D" cell socks, I used 4500mAh NiCd's, and they were much warmer. They didn't last as long as alkalines, but they actually put out some heat. 

Dave

*EDIT:* Awww, Mr H.


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## r1gm1n (Jan 28, 2010)

Nite said:


> *which charger is better you think for these cells? the Genix 1 hour charger or the genix 5 hour hour charger.*


 
The 1 hour charger (which is really 2 hours to FULL charge) will charge an even or odd number of batteries.

The 5 hour charger will only charge in pairs (an even number of batteries).

Your application calls for 6, so no problem. But, if you ever want to use the batteries in an application that uses 1 or 3 batteries, you will wish you had the 1 hour charger.

Besides bicycle lights and flashlights (which do burn brighter), I use mine in a Canon PowerShot (faster recharge of the flash) and in an electric shaver (zoom-zoom).


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## Nite (Jan 28, 2010)

45/70 said:


> A bit OT, but I've never come across a portable heating device like you describe, that was voltage dependent. These devices are purely current driven, and good NiMH/NiCd cells _always _work better than alkalines, because of this.
> 
> I suspect that the NiMH cells you are trying to use, are suffering from voltage depression (which means they can't deliver significant current, as well, except at very low rates) and just can't deliver enough power to create any heat.
> 
> ...



I think that when I use the NimH AA holder...cells that are fresh...the voltage drops quickly so my runtime is shorter than it should be.

The jacket shuts off automatically when voltage is too low to protect the battery packs. a real problem when nimh cells drop down to 1.2

This is a great jacket...from brookstone.com its a windproof fleece..buy it from the manufacturer (not brookstone) with two rechargeable packs..youll save alot of money. lo medium high..soft fibers that heat up

Ill give the compnay a call..they have great service. last year he said use alkies, not nimh..NiZN would solve this if the voltage wont burn out the controller.

6 Nizn is like 3 volts more to start than nimh

thanks


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## 357mag1 (Apr 13, 2010)

Under load I've seen the Nizn as high as 1.75 volts but that was straight out of the charger. If they have been charged for a week their resting voltage sets around 1.82 and starts out under load right about 1.65 then settles in for 1.6volts for most of the run.


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## ThunderCloud (Apr 20, 2010)

r1gm1n said:


> The 1 hour charger (which is really 2 hours to FULL charge) will charge an even or odd number of batteries.
> 
> * The 5 hour charger will only charge in pairs (an even number of batteries).*
> 
> ...


Where did you get that information from?

According to powergenix website, the 3-5 hr charger charges 1-4 AA. Same as the 1 hour charger.

I want to get a set for my Sonicare toothbrush that takes AA's (zoom-zoom).


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## Mockingbird (Apr 21, 2010)

ThunderCloud said:


> Where did you get that information from?
> 
> According to powergenix website, the 3-5 hr charger charges 1-4 AA. Same as the 1 hour charger.
> 
> I want to get a set for my Sonicare toothbrush that takes AA's (zoom-zoom).



Apparently there is a new version of the 3-5 hour charger which isn't available yet. If you click on "More" info, it says coming soon. The batteries needed to be charged in pairs in the original slower charger as I understand it.


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## etc (Apr 21, 2010)

Sounds interesting.

I want to try them in FiveMega 3xAA body with Malkoff M30 module.


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## core (Apr 21, 2010)

Mockingbird said:


> The batteries needed to be charged in pairs in the original slower charger as I understand it.



And although the faster 1 hour charger accepts odd numbers of cells (got mine just today yay!), this direct quote from the manual has me scratching my head:

"1. Insert 1 to 4 AA or 2 AAA rechargeable NiZN batteries into the battery compartment; *batteries should be charged in pairs for optimal performance*."

I wonder what that means? If I insert a single cell it won't get charged fully? Because I find it hard to believe it would take longer to charge a single cell. Those are the only two possibilities I can come up with for "optimal performance".

The specifications page reads:
1 or 2 PCS AA 1500mA
3 or 4 PCS AA 750mA

If anyone's got any idea what they're getting at here I'd sure love to hear it -- I was planning on charging a single cell per day, but if that's gonna be bad for my cells then that's another matter.

Ahhhh wait... perhaps they are just trying to say it's best/fastest to not charge _more_ than a pair at a time? That would make sense.


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## Art (Apr 22, 2010)

Where do you buy this?
It would be interesting to use it on Led Lenser lights.. but I cant find AAA of this cells only AA.
Do they hold the charge ok?


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## 357mag1 (Apr 22, 2010)

I charge single Nizn cells all the time and don't see any performance difference during use than when I charge two or more.


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## BigusLightus (Apr 22, 2010)

I'm using the NiZn's in my 2xAA SolarForce host and driving a Malkoff M30. With only two cells it powers up nice and happy.

I've tried these in several lights with positive results. Not all are brighter due to regulation.

Safe chemistry, higher Voltage, common size, and non toxic. I hate to sound like an advertisement but I really like these cells.

My next test is 6xAA NiZn's in a 2D holder driving an 1185. We shall see...


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## sunny_nites (Apr 22, 2010)

Some more unscientific testing but from a couple of personal observations:

I use a set of the NIZNs in a 3watt Maglite and they work great. I tried them in Xbox 360 controllers and compared to Eneloops, they didn't last as long.

My guess would be that they can put out a lot of current but have a higher self discharge than Enerloops. So, good for high power devices but maybe not the best for low power, long duration uses.

Personally, I think they are great and I hope development continues. Looking forward to the release of AAAs and dare I hope, N cells??


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## h2xblive (Apr 28, 2010)

Does anyone know how to charge these batteries without using the OEM charger? 

I would like to use these batteries as an alternative to NiMH and Lithiums with radio controlled vehicles. For example, I could get the power of an 8 cell NiMH battery pack, but only use 6 cells. And no, I don't want to use lithium batteries since I must keep the exact form factor and approximate weight of a 6 AA NiMH battery pack.

I was told it uses CC/CV charge algorithm similar to what Pb and lithium cells require, but I was wondering what any of you guys had to say.


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## ampdude (Apr 28, 2010)

I think the NiZn will eventually take over NiMh as it has higher voltage, watt hour ratings will improve on them, and it seems to have low self discharge rates around that of LSD NiMh cells. I'll at least wait for the 2nd generation though before I dive in.


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## was.lost.but.now.found (Apr 28, 2010)

From PowerGenix FAQ:




PowerGenix said:


> *How quickly do NiZn batteries self-discharge?*
> 
> The self-discharge rate is the natural loss of battery power or energy capacity when the battery is standing idle and not in use. PowerGenix batteries have a self-discharge rate equal of approximately 8 percent per month at room temperature. This is comparable to other rechargeable batteries.


I was hoping for better, but I guess it's still better than conventional NiMH.


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## Nite (Apr 28, 2010)

was.lost.but.now.found said:


> From PowerGenix FAQ:
> 
> 
> 
> I was hoping for better, but I guess it's still better than conventional NiMH.



Link?


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## was.lost.but.now.found (Apr 28, 2010)

Nite said:


> Link?


 
If you Google "PowerGenix FAQ" it will be the first result.


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## Nite (Apr 28, 2010)

was.lost.but.now.found said:


> If you Google "PowerGenix FAQ" it will be the first result.



tried that and the first page was mostly links to this thread I'm in now

Ill try again

thanks anyway

btw the first hit is this thread.


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## core (Apr 28, 2010)

Here's the link in question:
http://www.powergenix.com/faq.php

Also if you read the Amazon reviews, NLee the Engineer did some self discharge tests and found them to be better (self-discharge-wise) than conventional NiMH but understandably not as good as LSD. 

As an aside though I fail to see why people insist on comparing NiZn to LSD in such a manner. If LSD works for your device, use them. If you want/need the extra voltage then use NiZn. Two different applications.


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## MarioJP (Apr 28, 2010)

I am starting to wonder if the extra voltage from these cells will increase charging performance in my mobile usb charger to charge usb devices. Eneloops are great and they do work well but the voltage sag that I think is hindering the charging performance and could be better if I start using Ni-Zn in my mobile usb charger instead of eneloops to charge most power hungry usb devices like a Iphone or Blackberry. In comparison in mAh side by side. which one would last more??. Eneloop or Ni-Zn??

I know the advertisement says 2500mWh. But how much of that mWh translates to mAh???. Since NiZn has a higher voltage could this affect current draw??. Like would it draw more or less current with higher voltage like 1.6 vs 1.2v in devices like power boosters such as my 4AA mobile to 5V usb charger?


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## Egsise (Apr 29, 2010)

357mag1 said:


> The flashlight used was a Quark AA Tatical R2......
> ........I didn't want to run them on a lower setting until they died completely as I understand that can shorten the battery life drastically.


Quark AA has overdischarge protection at 0.9V, which is still safe for NiMH, you mean it is too low for NiZn?


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## VidPro (Apr 29, 2010)

MarioJP said:


> Like would it draw more or less current with higher voltage like 1.6 vs 1.2v in devices like power boosters such as my 4AA mobile to 5V usb charger?


 
if it is anything like the 2 mobile voltage *boost*ing 5V usblike chargers i have: 
They dont have enough operation voltage with alkalines very shortly
hold out "ok" with ni-mhys but still as the voltage droops cant keep the boost going well.
they thrive with the higher voltage of the lithium cells and will drain the lithiums almost completely (way to much cost).

The boost pulls down the battery voltages , then the boost curcuit begins to faulter , it will either sputter or just stop at that point, not doing any usefull charging.
WHEN those are the symptoms, the additional voltage will allow the curcuit to continue to operate, BUT is not going to have the boost curcuit run that much harder, as they are limited in total output.

most boost curcuits (even some really bad ones) will draw less current from the battery when the voltage is maintained higher.
So 
if voltage holding was the issue, the higher voltage chemistry should maintain that better. the charge rate out of the device should not change much over the rate it was doing with good fresh cell items in it. So there shouldnt be some huge charge speed increase, just longer operation at full.

If your Cell charger always WORKS but just doesnt give you enough current EVER, then switch to a Direct drive 4xAA one, and use ni-mhy or even alky, they dont have to do a boost, they have enough total power in them, and with all the extra total power they can be stronger in their charge. Often they are pure simplicity and way higher efficency, but you wouldnt want to use it on something that cant cope with higher total power. Many (but not all) devices using USB charging work fine with the DD voltages that go from ~5.4-4.8v no bs, no lossey curcuit , no failing curcuit junk, no reverse charge of batts as it will cutoff when the voltage drops to low to act like a USB.
Stuffing Ni-Zinc into 4xAA with Direct drive, will raise the voltage to high, which could toast the USB input on the device. i have tested a few USB inputs on the li-ion charging stuff (pda, Phone, external li-ion solar thing) and they start to break around 7V, so i stay below 6V

When determining the "runtime" of the cell charger using a boost curcuit, you just do the Watts to Watts comparison of the battery, the ~2.5W of the battery capacity is then usefull figure. When voltage is higher the actual current drawn to get to the same watts is lower.

If the cell charger never has enough voltage for its cheezy curcuit thing in it, then having a higher voltage battery in there solves that issue, and the actual watt total of the battery is inconsequential, When, with the high voltage the thing actually Works, instead of sputtering and stopping.


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## VidPro (Apr 29, 2010)

think i finnaly fixed that post. remind me next time to read better :ironic:

What kind of 4XAA cell charger?


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## MarioJP (May 1, 2010)

well it does work and I forgot to mentioned that this wasn't a problem with my previous phone. Its the newer phones with a faster processor,3G,wifi that I can't seem to top it off on a single charge.

But it does charges my phone to almost full like 75 to 80%. My other phone would not only be topped off but still have charge left over from the eneloops.

This phone however drains them completely and its not fully charged.


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## VidPro (May 1, 2010)

Well if it drains all the cells then it is doing something right, or something wrong 

what is the Max capacity of the devices internal battery? logically even a really efficient or DD cell charger will have quite a bit of losses in the phones internal charger thing. then if the charger has driver too, the losses could easily get to 50%
(because of that some devices we skipped the curcuits and just add the battery direct instead)

so how does the device act with the mere 500ma charge of one of them small wall wart switching chargers , or via a computer?

there is one device i know of , that uses 2 methods, one for anything it THINKS could be connected to a computer, wherin it MUST stay below 500ma to not ruin a computers USB port. 
and when the data lines of the USB are Tied (specially) , a Specific Flag that the charge curcuit is trained to see, switches it into the faster charge. That device prefers to be charged with its own Data tied line charger (obviously)

plus there are some phone devices that actuall allow the charging curcuit to be rate changed, deep in the menu somewhere.

But what i really want to know is What is IN your 4XAA cell charger. i have one i made , and one i bought. the one i made is DD, the one i bought is also DD (batteries just direct connected plus cute led with diode to show it is on).

What kind of cord do you use to connect? I use some lightweight rollup (retract) cords, and they certannly slow down the max rate, because the small wire, but is sufficent.

and how far can i go off topic rambling , and making more errors


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## MarioJP (May 1, 2010)

This charger is weird. You can use from 2 to 4 AA to start the charge. I can't tell if this charger has a independent booster circuit per pair or its wired in parallel per pair. Its definitely not a 4AA one circuit.

All i know is if you pull one AA out out of 4 the charger is still on charging the usb device. Does not matter which AA you pull out either. This is a very interesting charger.

On the data tech specs. It pushes 800ma from the usb port. This explains why my phone gets warm after 5 minutes and sometimes my phone gets around 40c. I know this because I have a battery app that monitors the temp. When the phone gets to 41c the charging stops until the phone cools down.

http://www.tekkeon.com/products-tekcharge1550.html

My phone's battery is a 1500mAh Lion Polymer.


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## VidPro (May 1, 2010)

yup boost, so it wont go much faster or better.
so putting in Ni-Zi should work ok, the In voltage will still be below the out voltage, but it wont change rate much, depending on the boost curcuit it could increase effeciency slightly.

find the low end, to discover if it could drain them to far (being boost), how low does it drain cell items?

with that at least when using parellels the batts can maintain the current of the boosting better.

1500ma cell battery is not like your going to get 2x charges with it like they might with a cell that uses some 600-800ma battery.

i have some 800ma quoted boosters in some china ones, they arent 800ma, but i didnt test exact, as i would need a scope to see everything going on.

or just get a more simplistic 4xAA that is raw and direct, then dont put ni-z in that. 
if its working , its better than some  mabey best to enjoy that, vrses re-wiring it.


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## MarioJP (May 1, 2010)

VidPro said:


> yup boost, so it wont go much faster or better.
> so putting in Ni-Zi should work ok, the In voltage will still be below the out voltage, but it wont change rate much, depending on the boost curcuit it could increase effeciency slightly. find the low end, to discover if it could drain them to far.
> at least when using parellels the batts can maintain the current of the boosting better.
> 
> ...



Won't Ni-zn burn this charger out??. one time I bought energizer Lithium ultimate. The usb charger was making a buzzing pitching noise, or a low pitch sound when it was charging my phone. and the AA's were getting almost hot!. The whining pitch was louder when using 2 AA than using all 4. But no buzzing or low pitch noise when using NiMh cells 2 or 4. With that said I am not using lithium AA on this charger again lol.

and as for the eneloops cells. When batteries are drained I measure the voltage the moment i take them out.

all 4 of them read in my multimeter 0.90 idle voltage. if not lower sometimes 0.85V off the usb charger. I have to wait until the voltage recovers back to 1v before I i put them in the charger


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## VidPro (May 1, 2010)

did you load 4 lithium AA cells or 2 ?
if the thing is going to freak out over lithium, and it is not because the Energyser lithiums overcurrent kicked in, then it will freak over these.

the energyser lithiums will kick in overcurrent protection, when it does , the voltage of the lithium will drop, the booster will increase in current as the voltage drops, then the booster will squeal like a pig and , and then heat up, then the canoe turns over and the hillpeople will kill everyone  i saw the movie

on the other hand the NIZN also break on very high currents.

try a Direct drive 4xAA cell charger with enloops, kicks butt no losses , no wastes, no curcuit junk, other than in the device your charging, no reverse charge, long live the batteries.


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## MarioJP (May 1, 2010)

Started off with 2 but the pitch was loud and heats up the batteries too fast. The spring contacts got too hot to touch. With 4 reduced the pitching and heat by a little.


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## VidPro (May 1, 2010)

well it sounds like it has some efficency issues. dont they all.
these devices are not often sold as being permenent chargers, and charge WHILE operating type of things, more like get you by for a while, till you get to a real power source.
that is why i go with adding on battery, extended battery, solar , and all the other methods of surviving without a power cord.

note the word "Emergency" often utalised.


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## MarioJP (May 1, 2010)

I did not use the lithium cells too long. Just seems this charger is meant for nimh cells. No pitching and does not heat up with 4 of them. so Higher voltage is bad??

with the nimh cells that are rated 2000mah it does charge my phone from 10 to 75-80% on a single charge. Not bad though I guess what i can do is turn off most of the phone services when its charging to maximize the charge. like dim the display shorten the time for the display to turn off.


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## VidPro (May 1, 2010)

MarioJP said:


> I did not use the lithium cells too long. Just seems this charger is meant for nimh cells. No pitching and does not heat up with 4 of them. so Higher voltage is bad??


 
Your testing showed that higher voltage lithium was bad news, they are higher voltage just like the zinc.

You were certannly smart for stopping a bad situation, from getting worse, but it works on 3v , it has a driver, it outputs 5v , it has to be a boost , , , hmm mabey it was one of those really loose boosters, like a voltage doubler curcuit. as the voltage input changes so too does the output voltage, and the total current.

could find out how it acts quick enough, either using a adjustable power supply, or just doing I/O readings on both sides of it.

approx guesses: (including probable realities)
4x2000ma batteries ~9 watts
the phone is sucking ~1W/h while on
~4 W/h output out of charger on a good day
~1.5 W/h watts lost via both charge curcuits
2 hour charge time with use
~4.5W li-ion battery
that is completly par.
battery dead even though it has the "watts" to almost charge 2 times,


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## MarioJP (May 1, 2010)

the only readings i am able to do is when using 2 cells. I measured the current as the charger was charging. boy does it draw quite a current almost 2A! lol. No wonder the spring contacts gets hot!. Don't think Lithium AA cells would appreciate that kind of current draw, especially if its constant current. At that rate and if I walked away. The AA Lithium cells would get too hot and possibly start melting the plastic lol.


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## h2xblive (May 1, 2010)

So I take it NO ONE knows how to charge these cells in series?


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## Ray_of_Light (May 1, 2010)

For series charging of Ni-Zn AA batteries, use CV method, 1 A limited, 1.9 V per cell, and terminate the charge when the current drops below 90 mA.
You need a thermal stop if the temperature of any battery in the pack raises of 15 C over ambient temperature, or 40 C absolute temperature.
If you want the 200 full cycles from a pack of Ni-Zn, you need charge balancing and temperature compensation, otherwise with a simple series charging at 1,9 V /cell, you may end up with 20-30 cycles. Unlike Ni-CD and Ni-Mh, you can't use slow charging to equalise the cells charge unbalance, because they will leak.
To keep the pack alive, you need to recharge every month, or everytime the open circuit voltage of any of the cells fall below 1.68 V.

Hope this helps

Anthony


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## h2xblive (May 1, 2010)

Ray_of_Light said:


> For series charging of Ni-Zn AA batteries, use CV method, 1 A limited, 1.9 V per cell, and terminate the charge when the current drops below 90 mA.
> You need a thermal stop if the temperature of any battery in the pack raises of 15 C over ambient temperature, or 40 C absolute temperature.
> If you want the 200 full cycles from a pack of Ni-Zn, you need charge balancing and temperature compensation, otherwise with a simple series charging at 1,9 V /cell, you may end up with 20-30 cycles. Unlike Ni-CD and Ni-Mh, you can't use slow charging to equalise the cells charge unbalance, because they will leak.
> To keep the pack alive, you need to recharge every month, or everytime the open circuit voltage of any of the cells fall below 1.68 V.
> ...




Thanks for the suggestion Anthony, but can you explain where you got that information from? I thought on the website (at least one of them for NiZn) it called for CC until a certain point, then CV until the end of charging. I have been told this is how Li-Po and Li-Ions are currently charged, except the voltages are at different levels than NiZn, obviously.


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## core (May 1, 2010)

The PowerGenix spec sheet does in fact call for a two step procedure:

- Constant Current: From C/2 to C to 1.9V per cell
- Constant Voltage: 1.9V/cell until current < 75mA

But that is not in series, which I think is the key here.


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## MarioJP (May 1, 2010)

why can't these cells be slowed charged unlike ni-mh cells?


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## Ray_of_Light (May 2, 2010)

Nickel-Zinc is a very old and well known battery chemistry, so is their charging parameters. Before Powergenix batteries, Nickel-Zinc chemistry never made to the mass market because of their very limited number of cycles, caused from some unappropriate properties of the zinc. 
The problem I see with Powergenix battery is that, unlike Ni-CD and Ni-MH, there is no mechanism to recombine hydrogen and oxygen which produces at end of charge.
This is the reason why the battery cannot be overcharged or trickle charged, and charge has to be terminated when the idle currrent falls below 90 mA, and the series packs needs charge balancing. Overcharge will cause a leakage.

EDIT: * CV Method with 1 A current limit * is "about" the same to say CC at 1 A, then CV at 1.9 V till 90 mA idle. Pure CC+CV rely on a voltage comparator to switch source impedance at 1.9 V, while current-limited CV act as CC until the cell try to draw more than 1 A. 
The first method is the one suggested from manufacturer for single cell charging, but is not suggested for series packs unless you closely monitor each cell with a balancer. 

Anthony


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## MarioJP (May 2, 2010)

Slow charging will cause them to leak? isn't the charge suppose to stop once voltage hits 1.9?


Edit: 

Looks like we have one bad review about these cells at Amazon






*5 dead batteries after Wii and XBOX 360 usage*, May 2, 2010 
By *Kristopher L. Gainey



* (Norfolk, VA)

*This review is from: PowerGenix ZRPGX-AA8 AA 1.6v 2500 mWh ZiNc High-Voltage Rechargeable Batteries -8 Pack (Green) (Electronics)* 
I've already tossed 2 of these AA batteries and now have another 3 that refuse to charge and show ~0.4v on my multimeter...this just after about 5 uses in Wii and Xbox controllers. I bought them because they're made from less toxic materials but if they're not going to hold up...I may be switching back to NiMh soon.


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## VidPro (May 2, 2010)

but did the amazon user indicate that he used the proper charge alogrythm?


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## MarioJP (May 2, 2010)

isn't what the Powergenix charger suppose to do??


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## Paul_in_Maryland (May 2, 2010)

*Re: charging NIZN AAs*

The Amazon reviewer apparently bought the 8AA pack without the PowerGenix charger. I suspect he tried to charge them in a charger meant for nickel-metal hydride AAs. I have nothing but praise for my NiMH AAs. I now choose drop-ins whose voltage band lines up well with 1AA, 2AA, or 3AA NiMH output voltages. for this reason, I steer clear of drop-ins regulated from 3.6 to 4.2v; that range falls within the NiZn hole between 2AA (3.2V) and 3AA (4.8V).



MarioJP said:


> Slow charging will cause them to leak? isn't the charge suppose to stop once voltage hits 1.9?
> 
> 
> Edit:
> ...


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## Conan (May 3, 2010)

MarioJP said:


> isn't what the Powergenix charger suppose to do??



Maybe he read your post and charged them in a Ni-Mh charger too.


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## Bapman (May 7, 2010)

Hello, I'm a newbie

Anthony ,could you give more information (if available) about proper care and 

maintenance of nizn batteries.

Thanks!

Ben.


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## r1gm1n (May 8, 2010)

Bapman said:


> Hello, I'm a newbie
> 
> Anthony ,could you give more information (if available) about proper care and
> 
> maintenance of nizn batteries.


 
http://www.powergenix.com/charging.php


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## Bapman (May 8, 2010)

r1gm1n, thanks for the reply. 


Ben.


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## MarioJP (May 9, 2010)

Despite of the eneloops being the best nimh out on the market today. They simply can't compete when it comes to voltage. In some devices the voltage is too low to use nimh but at the same time offer more runtime than alkalines??. So they came out with a battery technology that solves both problems??.

I wonder if these cells will put a dent in NiMh. Pretty impressive for being the first generation of these cells. Just imagine second or even third generation?. Then what??.

when nimh cells first starting to come out they were crap. and the voltage problem was a big deal at that time too. Not so much these days since electronics can handle both chemistries.

I just wished this technology like these Ni-Zn cells could of came out loooooonnngg timmee agooo.


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## jcw122 (May 10, 2010)

For reference, I think I was told last summer by 4Sevens in an email, that their runtime ratings are based off *2500 mah NiHM batteries*


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## MarioJP (May 10, 2010)

I would have to say that Higher capacity Nimh are becoming a hassle to take care,yet you don't get much performance out of them. These cells in the other hand have lower capacity but with higher output voltage. I want to do some tests and do a comparison in devices that we use every.

I want to tests these cells in my mobile usb charger to see if the extra voltage can make a big difference versus higher capacity nimh cells. Learned that mistake to never buy nimh cells that are 2500+. You don't gain much out of them if any at all. (Though hope these ni-zn cells does not fry my charger my usb charger lol).

And I want to keep my eneloops as a backup. I ended up ordering ni-zn cells for 2 reasons. 1. I am realizing despite eneloops being 2000mAh. The charging performance drops dramatically when the voltage sag. I have to disconnect the phone from the charger to see how much power is left and apparently all 3 led lit up instantly but when I plug the phone back all 3 led lights go off and eventually you see 1 lit. This is telling me that the cells are not yet low but the voltage just drops too much. In the end that one led stays on for a while.

2.I want to see if higher voltage makes the charger perform better.

This is just weird. Unless of course the 3 led indicator is not accurate then that would make a lot of sense!.


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