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Source for Rechargeable AA batteries for PCB mounting

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HammerForStickingOutNails:
Hello!

For a little project I need two AA-size 1.2V 2000+mAh rechargeable batteries (LiIo, LiPo or NiMh, no NiCd) for print mount on a PCB. All I could find however were batteries with wide solder tabs for creating battery packs, and most of the tabs were in Z configuration (one tab showing in the opposite direction). And as soon as I filter out the crop of cheap no-name Chinese batteries (which I want to avoid for several reasons) then there is nothing suitable left.

What I am looking for are AA-style rechargeable batteries with either pins for PCB mount or narrow solder tabs (the ones with a hole at the end to put a wire through) which show in the same direction and which have a capacity of 2000mAh or better (I'd prefer something in the 3600 to 4000mAh range).

Does anyone know where to get such batteries from? Since I'm in the UK I'd prefer a source in the UK or Europe.

Of course I could fiddle these batteries in by soldering another tab on them, however I would prefer to have batteries which already come with suitable tabs, especially as space is constrained.

JoannaK:
First.. Trying to limit some options.. 
- NiCd are out since they don't have mAh you are looking at the size.
- As far as I know, all Lithium technologies are around 3.6V per cell.. so it's too high woltage.

So NiMh (or perhaps NiZn?) it is..

Digikey have at least couple types that seem to be usable. (was second I looked, after Farnell)
www.digikey.com/product-detail/en/NH15/N703T-ND/1040726
www.digikey.com/product-detail/en/HHR-210AAC4B/P220T-ND/598006

As a word of warning .. If you'll look batteries from sites like Ebay, alibaba or any of those China-exports,  the specs are most likely badly inflated. As far as I know, there simply are no AA size 4000mAh NiMh available, and making those would reguire all new technology.

I'm sure there are many well known and respected Accu/battery sellers at net (or even local there) but I can't give any names off hand. I'd expect someone else to fill in here.



Astroplio:
You have absolutely no room for a PCB mounted battery holder?
This will allow you to use the best NiMH battery you can find for your application instead of looking for what's it is available now to you with solder tabs.

George

IanB:
Well, first a few facts for you:

1. NiMH cells are nominally 1.2 V and in the AA size come in capacities from about 1600 mAh to 2700 mAh, with 2000 mAh being the common conservative figure.

2. LiIO or LiPo cells are nominally 3.6 V (or 3.2 V for LiFe), and in the AA size come with a capacity of about 600-800 mAh (you get about 1/3 of the capacity because you are getting triple the voltage).

3. Lithium ion cells use completely different battery management and recharging technology from NiMH and you have to pick one or the other to design around. You can't just mix them up as if they were interchangeable.

4. No AA size cell has a capacity anywhere close to 3600 mAh. This is technically, totally unfeasible.

5. Tabs are not fixed to the batteries by the manufacturer. The tabs are affixed afterwards by vendors or pack assemblers using a tab welding machine. If you find a vendor who can fix tabs to the cells, you can possibly contact them and ask them to fix the tabs the way you would like. Or you can simply solder wires to the standard tabs that are attached in the normal way.

6. Have you considered using a battery holder? Rechargeable batteries do wear out after a while and may need replacing. Putting them in a holder makes this easier than re-soldering.

HammerForStickingOutNails:

--- Quote from: JoannaK on December 28, 2012, 11:36:45 pm ---First.. Trying to limit some options.. 
- NiCd are out since they don't have mAh you are looking at the size.
--- End quote ---

As stated in my original posting I already ruled out NiCd, not just because of the very low capacity.


--- Quote ---- As far as I know, all Lithium technologies are around 3.6V per cell.. so it's too high woltage.

So NiMh (or perhaps NiZn?) it is..
--- End quote ---

A while ago I have seen some AA LiIo cells on an exhibition but I can't remember who made them, and a search didn't come up with results, so I guess NiMh it is.


--- Quote ---Digikey have at least couple types that seem to be usable. (was second I looked, after Farnell)
www.digikey.com/product-detail/en/NH15/N703T-ND/1040726
www.digikey.com/product-detail/en/HHR-210AAC4B/P220T-ND/598006
--- End quote ---

Thanks for the links! The Panasonic battery seems to have tabs in Z config but the Energizer battery looks like what I need.


--- Quote ---As a word of warning .. If you'll look batteries from sites like Ebay, alibaba or any of those China-exports,  the specs are most likely badly inflated.
--- End quote ---

I'd never buy batteries (or flash memory cards) from ebay just because of the sheer amount of crap and fakes sold there, and especially with rechargeable batteries I keep with the major brands.


--- Quote ---As far as I know, there simply are no AA size 4000mAh NiMh available, and making those would reguire all new technology.
--- End quote ---

Not necessarily. For a while now we use GP 3600mAh AA rechargeable batteries in various applications, and while not having tested their true capacity the runtime suggests that the rating is indeed quite accurate.  From what I have heard a 4000mAh variant is already in the works.

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