If you can get your hands on a lab psu that can output 20a, that’s the ticket. Set the voltage low for safety, like 2v should be okay. Voltage does not affect heat and fusing. Set current limit close to zero, short across the strip, slowly turn up the current until you see what you want. Most reasonably priced lab PSUs stop at 10a. You might be able use half thickness fuse to test. Not sure if things are linear enough with heat affecting things.
There’s also Ruideng DPS-5020 which might be cheaper and more compact if you can feed it enough power.
Alternatively you can also try one of these
There are many variants with different prices. The limit for the linked one is 150w or 20a whichever is reached first. If you set voltage under 7.5v you can pull 20a. Might need to watch the cooling.
IIRC the one I linked (purple fan with pretty displa) is analog controls. The display shows what’s happening, and you twiddle the knobs to change parameters. No digital control.
The one below has an ugly display and is only 10A, but has digital control (you set the parameters you want numerically, then hit the “on” button).
Maybe 2 of those in parallel to get 20a of load…
All that said, I think you should skip the cell level fusing.
@tyesk8 There are different ways to fix your pack/cells.
I used silicon other use velcro tape.
Pack number 1 starts where the main negative wire is connected, the last pack is where the main position wire is connected.
Out of curiousity what BMS did you end up using? I see that you were initially using the HCX D223v1 (I’m using those in my builds). Assuming the D140 based on your charge only statement?
I’m assuming that count is then linear starting from main negative terminal on the pack. I have a 13 wire BMS for my 12s pack I would then do the following based on my diagram moving from left bottom to top left:
B- on BMS would go to main negative
1 would go to positive side on P group 1
2 would go to positive side on P group 2
…
6 would go to positive side on P group 6
7 would then continue top right working my way down each positive until I reach 12 on main positive.
You should get a wiring diagram with your bms. There are different kinds. It can be that B- is shared with b- or b0 (different Label but First Balance wire) so you need only the main B- and the first balance wire goes to first pack plus. There other bms where you need the first balance wire to connect to the first pack minus and than go on with first pack positive, second pack positive and so on
Dont overthink and just use regular glue, if you dont go cheap on it and put a reasonable amount it will be stronger than the heatshrink, and if you try to remove it it will break the heatshrink, especially if its really hot when you apply it
Any brand name hot glue will do it, but dont go with the cheap sticks from ebay
No need for this
I would personally use 10awg because its much easier to solder
who can design a pcb!? so frustrated trying to get someone to put my hand drawing into a gerber file. help me do it and i’ll put the pcbs up for sale at cost.
similar to this but 48 cells instead of the 24.
dm if you can help.
When I’m building my battery pack do I connect the power cable between the p packs first or do I connect the balance cables from each pack first? Note, I’m not connecting a BMS.
Need some quick help… I have an old prototype pack I had made from a pack with dead p groups during the winter to try and have a backpack battery system. Works great but my problem is this. I charged it and forgot to use it. What household item can I use to drain it? Please do not, I repeat, please dont school me on the methods I used with this. I had fun doing it and learned from it.
easiest/cheapest way is to find someone with a 8s hobby charger. Other ways cost time/money/knowledge. The cheapest other way I can think of is a handful of halogen lightbulbs and some googling and calculations.
If you have an old incandescent sitting around (i don’t anymore lol) just use that. Its getting harder and harder to find incandescent but most dollar stores still have some shitty ones that work for a few hours these days.
)
