Here’s a little something I would like to use for parallel groups with cell level fusing. The goal is to easily put double stack groups together and have a channel in the middle for either a copper braid wire or a thick nickel strip. Then put a fuse wire between the wire/strip and each cell. Only recently I learned that it’s possible to spot weld fuse wires to cells. Just soldering should also be OK here though.
At the same time I want to keep it as compact as possible, ideally no bigger if I just glued the cells together.
I have made this model some time back when learning the Fusion 360:
I printed it today with my new Prusa mk3s printer. This is actually my first successful 3D print. I just exported an STL file from Fusion, loaded it to the Prusa slicer and left everything at defaults. It came out pretty well.
I’m not too keen on putting my life in the hands of a couple zip ties, but aside from that I’m impressed with design and I really want to see where this goes
Hey all. I’m building my first battery and wanted to get some constructive criticism on my progress thus far. This is a 10s3p build with Sony vtc6 cells. Nickel is sourced from Liion Wholesale. I’ve done both the brine test (scored the nickel first) and the spark test and nickel is pure. I will be using single 14 awg high strand wires for the series connections as well as bus bars. 12 awg HS for the main terminals and an xt60. The vtc6’s are capable of 45 continuous so I think 14 awg is sufficient as it seems to be able to run 55 continuous without any problems for short lenghts. Here are my wiring diagrams:
I’m new to battery building, and someone correct me if I’m wrong since I got schooled on how much nickel to use earlier, but I think that much nickel is a little excessive. It looks pretty thick, so I imagine one parallel strip and 1 or 2 tabs is sufficient for making those serial connections
Thx man. Its 0.15mm x 10mm nickel and I could’ve probably gotten away w just a single strip but I would rather over-engineer the pack rather than the alternative. Vtc6’s can do up to 30 amps tho so they’re more powerful than 30q’s which is why I chose the bus bar route. That and it reduces resistance.
Excellent safety precautions by adding that insulation under the folded nickel. I would just recommend a tighter grouping for the welds on the positive terminal but aside from that, seems great. Try to keep the nickel away from that void though. I know it’s already spotwelded and theres no chance of it sliding underneath however so you’re fine.
These look dope IMO. I’m super uninformed and have been curious about cell level fusing–whats the difference here in how the terminals are connected? Each battery is individually fused or what? Advantages/disadvantages?
That looks pretty cool, but if that was mine I would rather do some M3 studding to hold everything together, zipties will fracture under fatigue
Alternatively put a massive radius on the zipties and have the blocks on the corner so the plastic doesn’t bend (take advantage the connection is already 90 degrees)
Ya, irl I don’t plan on running the wires that way. That diagram was more for me not fucking up wiring the bms. Think it might be a bestech but not sure. It’s wtv bms came w the bkb battery.
Thx man, ya I learned that as I went on and the groupings got much tighter. This was one of the first p groups I did. I actually blew through the nickel on one and that smartened me up in a hurry,
@YeetMeat that’s fish paper. You score it to create a nice clean fold for double insulation on the pos terminal.
oo yeah ik what the fishpaper is, I was talking about the little white bit at the 90 degree bend. But I can’t tell if that’s apart of the wrap or separate.
Not sure I follow. Do you mean the wiring itself is incorrect or my labelling of said wiring? This diagram is a reproduction of how the original pack was wired. I took detailed pics of all the balance leads when I disassembled the pack. There are 11 wires going into the bms via the jst connector. Balance 1 (labelled B1) was connected to the main neg terminal. Balance 10 was connected to the neg terminal of cell 10 (B10) and the 11th wire (B+) was connected to the main pos terminal.
I just exported an STL file from Fusion, loaded it to the Prusa slicer and left everything at defaults. 
It came out pretty well.
