I’m trying to reason about how to build a two layer pack with cell level fusing. Any ideas out there? I’ve been looking around and nothing so far. I’ve got to build this thing safe!
Did you see this thread?
I’ve read through it before but I don’t remember anything about a double layer design.
Here’s a modular design I came up with a while ago. The sides of each group of cells is spot welded with a nickel strip thats folded over a sheet of fibreglass like this stuff:
Then I use brass bars as a bus bar on each side with the fuse wires soldered between the bus bar and nickel strips. Both the bus bar and nickel strips are held in place with plenty of hot glue (Doesn’t look particularly tidy but it does the job). Then I glue another layer of fibreglass over the top to as a layer of protection/insulation.
Oh sweet! Cleaver design. What sort of enclosure did you put those batteries in?
Cheers. These are being used on a Loaded Vanguard so I made a pair of enclosures out of ABS. 6 packs in one and 4 packs + ESCs in the other
I’m working on a different approach. Just spitballing now, but I really like the PCB that @Blasto and @Kaly are using. Super reliable and easy to troubleshoot. I’d like to modularize the idea to make it airplane safe and completely toolless. Uses TE Micro Mate-N-Lok connectors for the balance leads. Hopefully they’re vibration-resistant enough for the application. A 3D printed fixture may be added to secure these connectors in place.
Something like this:
that implements this:
I really like how @Kaly does his packs:
I just need to work on the PCB’s, which is easy.
Its so subjective, but what is the range your getting with the 6P pack?
I am trying to figure out how to do cell level fusing for 10SP4 pack in 2 layers. Thinking to cover positive ends of each P group by a PCB cut to its shape with 4 drilled holes for cathodes of the cells. Then run fuse wires from the cathodes to the PCB.
Lot’s of ideas in this thread:
That’s not a bad idea, I think that is what @michaelcpg achieved above. The only negative of that approach is having to make sure you have space for the extra length of the cell + the PCB or Fiberglass. If you have the space for it, do it. Are you pulling the trigger on it? Care to share some pics of the experience?
I’m currently working on a 1.1Kwh mountainboard build and I’ve come up with a slightly more refined (and hopefully much simpler and quicker to build) design for the new pack.
Although it’s more designed for single layer packs, it could probably be fairly easily used on double layer packs with no issues and should only make the cells a couple mm longer.
I’ll see if I can find some time this weekend to draw up a model of the idea if anyone is interested
I am interested too.
Speaking about your double layered design above…
Why do you put fuses on both sides of cells? It is enough to fuse only one side, right?
I am thinking about the following modification: Put fiberglass plates and fuses only on one side of a pack. Connect the other side by nickel strips as usual. Make two packs like this and glue them by the sides that don’t have fuses. Then all fuses will be on the sides of the pack (mixed on pluses and minuses ). It should be easy for inspection, replacement of fuses, etc.
Hope it makes sense what I mean.
… also instead of bus bar I want to use flat wire like this
(because I already have it)
And instead of hot glue, I’ll use neutral cure silicone. (Hot glue is flammable.)
If you don’t want to worry about taping and wrapping the batteries, you can use brackets as such. Looks clear and easier to handle.
It looks like small packages of coke with cables sticking out
The idea behind the trapizodial design is to save space. There aren’t a lot or hardly any enclosures that fit 6P even with that design.
Oh. Thanks. I didn’t quite get it in the beginning
Still trying to decide if I’ll go for cell level fusing, or just spot weld the cells as usual. Sure I’ll post pics if I pull the trigger.