# aa Batteries from 3000mah to 3600mah



## ergotelis (Sep 6, 2009)

Hi, if anyone searches ebay, he will find numerous AA batteries rated till 3600mah.
So, has anyone tested any of them before?Or these one are not going to be any better than the best and well known 2700mah Sanyo batteries?
Is it worth giving them a try?For the moment i have sticked up with eneloops, but if even 3000mah are possible with some of them, why not?


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## mudman cj (Sep 6, 2009)

If you spend some time reading threads on this topic you will find that there is no such thing as a AA Nimh battery that will deliver >2700mAh over many cycles. This is a very complex subject matter, and battery performance depends upon many variables. The performance will depend upon the charging algorithm, charging current, discharge rate, required minimum discharge voltage, number of charge/discharge cycles, etc. 

The short answer is that none of the batteries you mention will be better than 2700mAh Sanyos.


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## Mr Happy (Sep 6, 2009)

Even 2700 mAh cells do not achieve 2700 (they usually deliver about 2650 mAh in testing).

3000 mAh is impossible in an AA cell.

3600 mAh is utterly impossible.

In addition to being overrated, unbranded cells are going to be crap. If you want any chance of decent quality make sure you buy cells from a manufacturer with a known pedigree.


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## ergotelis (Sep 6, 2009)

When you mention that 3000mah is impossible, it is due to technology limits of nimh?So, isn't ridiculus the fact that there are so many brands claiming something impossible? 
You have already at least convinced me not to buy such batteries, but, because i am a bit curious, i would like to know if someone tested any of them and what were the results.Thanks!


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## Mr Happy (Sep 6, 2009)

ergotelis said:


> When you mention that 3000mah is impossible, it is due to technology limits of nimh?


Yes. The charge is stored in the chemicals of the electrodes and the electrolyte. Bigger electrodes means more capacity. But the size of an AA cell is fixed, so there is a limit to how much you can squeeze inside it. If you try to squeeze more of the active chemicals into the container you have to sacrifice something else to make room. The result of making such sacrifices is a cell that wears out quickly, damages easily and does not hold charge well. The true 2700 mAh cells already suffer from these problems. Even some 2500 mAh cells suffer from them.

Unless somebody comes up with a radical new innovation, 3000 mAh cells are not going to exist. If somebody did come up with such an innovation it would be big news and the cells would be announced by a big name manufacturer with lots of publicity, not shipped from unknown factories with no brand name.


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## ergotelis (Sep 6, 2009)

Your latest post really says it all,thanks!


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## distrbd (Sep 6, 2009)

Mr Happy said:


> In addition to being overrated, unbranded cells are going to be crap. .


So true.



ergotelis said:


> ,..i would like to know if someone tested any of them and what were the results.Thanks!


 
Well I did buy 4 of these cheap batteries from ebay ,the brand is GP(gold peak group) it says 3000mAh but after 5 or 6 break-ins and refresh /analyze cycles all I got was 905 ,856 ,1460, and 1235 mAh!
I only paid under $7 for them so I wasn't really heart broken to find out they are crap ,the reason I bought them was to use in my camera but I have found out the good old Eneloop will be plenty for my occasional use.
So the bottom line is in my experience these no name 3000 mAh batteries you see on Ebay are simply worthless.


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## ergotelis (Sep 6, 2009)

I saw these gp too, and these are thought to be good batteries!So bad performance, really bad!


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## h2xblive (Sep 6, 2009)

ergotelis said:


> When you mention that 3000mah is impossible, it is due to technology limits of nimh?So,* isn't ridiculus the fact that there are so many brands claiming something impossible? *
> You have already at least convinced me not to buy such batteries, but, because i am a bit curious, i would like to know if someone tested any of them and what were the results.Thanks!



I've never known anyone to claim their AA NiMH cells have 3000 or 3600 mah capacity.


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## ergotelis (Sep 6, 2009)

Search ebay, you will find a lot of brands, though most of them not well known or just unknown.


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## TakeTheActive (Sep 6, 2009)

ergotelis said:


> Search ebay, you will find a lot of brands, though most of them not well known or just unknown.


"*If it sounds too good to be true, it probably is...*"
​


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## EngrPaul (Sep 6, 2009)

It depends on the drain test cutoff voltage. :shakehead

I could claim my gas tank is good for 500 miles, but I would be stranded with no gas when I actually try it. :duh2:


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## TakeTheActive (Sep 6, 2009)

EngrPaul said:


> It depends on the *drain test cutoff voltage*. :shakehead


*AND* mA load!

I'd like to see someone graph this, if possible... (i.e. 5mA down to 0.5VDC) :thinking:


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## SunFire900 (Sep 7, 2009)

IMHO, NiMh cells should never have been pushed any further than about 2100mAh. When this was done, the cells became less reliable, more fragile and much more difficult to match. I found, after years of experience, that whenever I'd buy a set of 4 cells, I would be lucky to get 3 that would be within 100mAh of each other (which would be fantastic), and one cell would be even weaker. The weakest cell in the set becomes your best cell as it will give out before the others, and there is nothing the other cells can do about it. 

Yes, even with Sanyo's.

Like the old saying: "A chain is no stronger than it's weakest link."

Eneloops and the like are the best thing going right now in AA cells. They won't go dead in a month of sitting around like regular NiMh cells. It would be great if they were 3000mAh, but that will never be with this technology.

Everyone has their own experiences with these cells and many will disagree with my statements, but my experience tells me to avoid anything that runs off of multiple AA's (that meaning more that 2-4 cells). I've had it with them.






I feel better already.


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## EngrPaul (Sep 7, 2009)

Yes, I agree that it's better to buy consistent performing cells at a reasonable capacity, than to buy inconsistent cells with a high capacity.

I have a set of 2700 Sanyos. They are big, I had a few flashlights that they didn't fit into. One of them went high impedance, and now since I have three, the remaining ones are of less use to me.

The most consistent cells I've tested are eneloops & imedions. I don't bother buying anything else.


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## MarioJP (Sep 7, 2009)

I would like to know about the ansmann batteries, and these are known batteries that amazon sells.
http://www.amazon.com/dp/B000WDSFPM/?tag=cpf0b6-20

so far 4 have reviewed it and all claims they last a very long time. But then again its only 4 reviews lol. Though not cheap but has a new record of 2850mah. If this is true Consider me impressed.


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## Bones (Sep 7, 2009)

The reviews on the Ansmann 2850mAh cell are quite good. Regrettably, none include a capacity test.

Considering where this reviewer set the bar, I couldn't help but think he's had prior experience with high-capacity cells:


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## lctorana (Sep 7, 2009)

Bones said:


> The reviews on the Ansmann 2850mAh cell are quite good. Regrettably, none include a capacity test.
> 
> Considering where this reviewer set the bar, I couldn't help but think he's had prior experience with high-capacity cells:


Gosh, move over SilverFox! This bloke's the business!



Not.


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## MarioJP (Sep 7, 2009)

so how good are these batteries. I hear nothing but good from other sources as well, but not a lot of reviews.


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