Dimensions of DigiKey 18650 Battery Holder

[rmteo]

In case anyone is interested, here are the dimensions of http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=BK-18650-PC2-ND

 

[SnowplowTortoise]

What are you up to, sir? Do I smell an 18650 cell phone charger?!

Thanks for the info. Too bad I didn't know such a thing existed when I placed an order with Digikey last night (gonna try the LM7805 - seems simpler than the LM22671).

 

[lolzertank]

I just placed an order last Friday, and I needed these.

 

[Black Rose]

It's too bad that doesn't have solder tabs.

However if you build a tray like rmteo's 16340 tray, then it's great.

 

[rmteo]

I did not actually build a tray. What I did was to epoxy the individual 16340 cell holders together and then connected the tabs in parallel with copper braid - you can use any conductor material.

 

[kramer5150]

Thanks for posting this!!

I am almost finished with my parallel 26650 tray. I was a little worried the epoxy will not adhere well to the cell holder plastic, have yours been very durable?

I am using 1/4 thick delrin stock for the base of my tray. heres some build up pics. My soldering iron is warming up in the other room.

1xC trays cut in half and spaced apart for 65mm length

test fit

Bus-bars prior to soldering

test fit

My iron should be nice and hot now.... be back in a sec...

 

[clintb]

Kramer,

IIRC, those type cell holders are only good up to about 1 Amp before heating up enough to melt the plastic.

 

[rmteo]

kramer, those AA, C and D cell appear to be made from a soft, shiny material and I'm not sure how well they work with epoxy as I have not tried to glue them. The 16340 holders OTOH, are made from a harder material - almost like a glass filled engineering plastic - and hold together well with epoxy after roughening the surface with emery paper.

clintb, I use those D cell holders to charge 10000mAH NiMH cells at 3.6A (I like using this number as 1mAH of charge takes one seceond) and they appear to work well - the contacts do get slightly warm but definitely not hot enough to melt the plastic - YMMV.

 

[kramer5150]

Kramer,

IIRC, those type cell holders are only good up to about 1 Amp before heating up enough to melt the plastic.

Argh... I was worried about that. still brainstorming. I was thinking about flowing some more solder, in an effort to try and reduce resistance. Maybye wrapping the springs in copper braid too....:sigh:

 

[lolzertank]

Argh... I was worried about that. still brainstorming. I was thinking about flowing some more solder, in an effort to try and reduce resistance. Maybye wrapping the springs in copper braid too....:sigh:

You don't need to WRAP the springs. You could just do it like the resistance fixes for a Mag spring, by passing it straight through.

 

[clintb]

clintb, I use those D cell holders to charge 10000mAH NiMH cells at 3.6A (I like using this number as 1mAH of charge takes one seceond) and they appear to work well - the contacts do get slightly warm but definitely not hot enough to melt the plastic - YMMV.

Might have been the AAA and AA versions that melt around 1 amp of input current. The spring on kramer's unit does look bigger than the AA / AAA units I have here, and you're using 3.6A so I guess they'll be good enough. Just don't crank it up to 5A!