It would be much better if, instead of shutting down, a BMS would make a warning, say, a loud beep if something is wrong. There is a simple LiPo voltage tester that does just this - gives a loud beep if voltage of some cell gets too low.
Actually, I am not planning to use a BMS. I will make VGA balance connectors and charge the battery using a balance charger. This way I can easily see if there is a problem at charge time. But I want to implement some protection.
My main priorities:
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Safety while riding. I don’t want to add risks of blowing a fuse or blowing a BMS.
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I don’t want the battery to go in flames.
Cell level fusing sounds like a great idea. But it has to be done correctly.
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So, why fuses have to be on the positive side of cells? This was discussed in this thread, but I did not get the explanation. A fuse on the positive side can short as likely as on the negative side.
If I eliminate any possibility of shorts (thinking to use fiberglass fr4 plates between cells and fuses), can I put them on the negatives of cells? Is there any other electrical reason for them to be on the positive side?
More precisely, for easier access, I want to put them in alternating way: 1st P group - all fuses on plus side, 2nd P group - all fuses on minus side, 3rd P group - fuses on plus, etc.
Also thinking to use flat wire like this instead of busbar:
Will it work?
So 0.4 mm thick brass sheet will do right? How wide should 1 bar be??
Anyone know where to get 22 awg nickel plated copper wire in europe?
https://uk.rs-online.com/web/p/hookup-equipment-wire/0355079/
0,397 mm² this is almost AWG 21
https://uk.rs-online.com/web/p/hookup-equipment-wire/0355063/
0,652 mm² AWG 19
I wouldn’t go for AWG 22. It’s very thin and can break by vibration. AWG 21 or 20 would be much better!
This is my cell level fusing pack:
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Thanks mate! I might go with 21 awg instead. It’s only a 4p pack I’m making so
Chaka where did you buy/get the copper you attached to your batteries? Also what gauge is it?
How about this pack? So many P’ees
He’s no longer on here…
It’s really cheapper than buy a battery ?
was just watching guy who made it from flattening copper tube from the hardware store with a press. cheapest probably. i used to get stuff from basiccopper.com but kinda expensive
He can’t mean that the bus bar he used was 0.15" thick? That’s nealy 4millimeters
0.016" = ~0.4mm Brass Copper thickness i don’t kniw.
You’re right , I’m missing a decimal place. Thx
Where can I get the fuse wire? I looked up 20a fuse wire on eBay, but all I got were regular 20a fuses. I’m copying the structure of this battery for a flexible battery, but it would be great if I could copy the cell level fusing too!
Usa or eu?
The fuse wire is just copper wire??? I thought it was supposed to be a special alloy or something. Huh