Soldering cells

Im planning to make a 12s4p pack, using A123 26650 cells, what would be the ideal size of the nickel plate? should I go with the 8mm x 0.3mm? would the thickness affect the current flow?

thanks for sharing those info :thumbsup:

@whitepony has built a few packs. He will be able to tell you what thickness and width he uses.

1 Like

Thanks @lox897

Im using 10x0.15mm and current-reinforce serial connections with copper which I solder ontop of the strips. was never sure how “thick” my diy welder would be able to handle. the 10x0.15mm strips are good for about 15A!

1 Like

Sorry, would you mind to post a picture of it? U mean copper strips right on top?

like that:

I would say, there isnt any single nickel strip that will support the continuous current for reasonably sized batteries. but you can get around that problem with your battery layout - for example I build a trampa battery that has 6 nickel strips as serial connections (from each of the parallel pack cells is a connection going to the next). in that case, you dont need to reinforce, but if you have a single strip carrying the full serial load, it wont work. basically the last nickel strip of my trampa battery has to carry that load - thats why I reinforced the last + and - parallel row:

3 Likes

I totally understand now. Thanks for uploading those pictures, that made it really easy for me to grasp the concept.

I assume you built an E-Mbr, right? Did u use the vesc for that?

Never mind, just found it on endless-sphere.com Reading time hha

check this out https://www.youtube.com/watch?v=BlM9tn4531M

skip to 8:50 to see

1 Like

Ya that guys iron was way too cold. But it’s good to know to be extra careful when soldering the negative side of the battery.

What kind of welding rods did you get? I am soldering a 8s2p basen 26650 pack. and 10gauge is too bulky to connect individual cells together. How easy is it to solder the welding rods onto the batteries? Any tips? Links for the welding rods would also be helpful!

AI’m just about to assemble an 8s3p pack. The only copper brazing rods I can find are at Canadian Tire.

http://www.canadiantire.ca/en/pdp/copper-brazing-rods-3-pk-0580044p.html

They are listed as copper phosphorus with flux. Are these any good? My thought was to try 12g household wire or 12g multi strand silicone wire. I also have 8g and 10g silicone as well. Thanks for any advice.

Edit: Couldn’t wait. I used 12g solid wire rated for 220v and 45amps. The button side negative was the easy side. The flat positive side (A123’s are bass-ackwards) was a pain in the ass. My Hakko 888 had a hard time with the positive side. I’m headed out later to grab a nice butane powered iron to try and finish these up and maybe reflow a few ugly ones.