Battery Holder for 26650 M1 cells

[katou]

Hey, anyone know of a cell holder for 26650 format cells?

I bought a dealextreme 2-cell charger to use as a battery holder for the 18650 format cells I have, but they don't sell anything for the larger (dewalt M1 A123) cells

katou

 

[MitchJi]

Hi,

Are you looking for a way to charge or use a few individual cells?

If so any of the following will work:

If they have tabs, the easiest way is to use alligator clips.

If the cells don't have tabs, you can use a neodynium magnet, clip it in the alligator clip, and it should hold to the cell (it's kind of a hack, but it works).

Another method is to purchase "D" cell holders, cut them in two and glue them the appropriate distance apart on a flat surface (cardboard or wood, etc).

 

[katou]

Not bad, but I'm looking for something a bit easier. I can homebrew my own holder if I need to, but I'd much rather buy one - sooo much faster.

I can hack, but I don't want to in this case. I just want a nice little holder I can snap cells into and out of for charging/testing.

Katou

 

[amberwolf]

I just went searching the place I thought for sure would have something, CandlePowerForums, but all I can find are hacks of various holders or chargers. And completely custom-made holders, usually for one-off flashlights.

Best one I saw out of the latter category is this:
http://www.candlepowerforums.com/vb/showthread.php?t=261193
http://public.fotki.com/cmacclel/lights-1/7x-mc-e/
View attachment IMG_1677-vi.jpg
Looks simple enough to emulate in various configurations; appears to simply use all 5 of the cells in direct parallel, connected via the brass plates.

I can't find any commercially made ones at any of the regular big distributors.

 

[katou]

Those are 18650's I believe.

I am using a Dealextreme dual cell charger to hold 18650 cells for testing with my CBA III (took out the charging board, for 7$, I don't mind)

But I need a holder for 26650's.

If you guys can't find one, I doubt I ever will. I may have to resort to the road Mitch suggested, although I am loathe to do it.

Katou

 

[cell_man]

If they have tabs I would use a clip or solder the test lead onto the tab. If no tabs, I'd try to fabricate something that would just push terminals up against the ends of the cell. I use toggle clamps for the pouch cells and clamp the tabs to copper bus bars. You could use toggle clamps to apply the necessary force to get a good connection.

If doing single cell testing with a resistive load, the attenuation on the termination can be very significant and has a big effect on results. If you have a constant current load it doesn't make so much difference if you have some attenuation in the termination, as long as your cell voltage measurement is remote from your load.

 

[Doctorbass]

BATTREYSPACE.COM HAVE THEM

Doc

 

[katou]

I already checked there, and they do not have any holder like I need.

This is the one they have:


I went to batteryspace.com and searched on 26650, that's all that came up as a holder.

I'm looking for something that looks like this:


Still no joy.

Katou

 

[amberwolf]

Those are 18650's I believe.

He says in the thread:
"Custom 5x 26650 series Battery Holder"

But I need a holder for 26650's.
If you guys can't find one, I doubt I ever will. I may have to resort to the road Mitch suggested, although I am loathe to do it.

I'll keep an eye out, but so far I haven't found the ones I thought I had once seen at CPF.

Maybe you can get j3tch1u to make you some with his new Makerbot.
http://www.endless-sphere.com/forums/viewtopic.php?p=271696#p271696

 

[katou]

I don't doubt that the description lists 26650's but that picture does not look like it. Those cells look much too thin to be 26650's given the length showing.

Back to the drawing board.

Katou

 

[Papa]

Do the A123 (26650) cells have the same physical dimensions as the IMR-26650 cell? I assume they do, but need confirmation.

 

[katou]

Yes, the code indicates the size.

26650 = 26 mm dia, 650 mm length.

By the same rule, 18650 is 18mm dia, 650mm long

Cool eh?


Katou

 

[docnjoj]

I think they are only 65 mm long! 650 is kind of big!
otherDoc

 

[Papa]

The 3/4" PVC coupler ID is 26.79mm. The IMR-26650 cell OD shown below is 26.30mm. You'll end-up with approx. 6.3mm gap at each end - sufficient room for the contacts and/or springs. I glued 2 caps as legs, but the number of mounting possibilities is endless. This was a 5 minute hack at a total cost of $1.69

* (1 ea.) 3/4" PVC coupling
* (2 ea.) 3/4" PVC caps

 

[katou]

Oh geez. Yes, 65mm, not 650!! And I was raised in metric, oh, the shame...

That is a nifty hack papa! I really was hoping for a purchased solution, but you've come up with the next best thing IMO.

Nice work. I like how you left the crumbly bits from cutting for the photo.

Katou

 

[amberwolf]

Cleaning up the crumbly bits is the other 25 minutes of a 30-minute hack.

I like this too, and it could be a good solution for single-cell holders. Potentially it could be used for multi-cell series holders, too, using some of the cut-off bits to make inter-cell retainers.