Yes I am looking at a spring loaded cart with nickel ends fuse wired between the nickel ends to the bussbar, maybe with a little poron
@banjaxxed. Whats the reason for the fusing? Only tesla does it and the rest of the world somehow manages go arround without them. Cars, laptops, tool packs, golf carts etc. I mean 99.99% of the market that uses lithium cells dont use them. I can point you where this madness started(my colegue) and even he admited after a while that individual cell fusing on bikes is overeoveroverbuild let alone skateboards. Internal shorting is so rare, it just makes no sense what so ever. Even worse, cell fusing on small packs is dangerous. I suggest to watch some vids from elithion by Davide. They make high end BMSâes and are competent.
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Recently Someone in here made a New pack with New batteries. Somehow two cells from the entire Pack got damaged or were damaged. these two cells dipped below 2,5v⌠A cell Level fuse would have Safes the healthy cells some cycles (because of the p group balancing behaviour) So cell Level fuse cannot be over build when such things Happen. It wont Happen as often as other failures but you should not count them out. But they arent neccessary too.
Donât think cell level fuse would have made a difference here.
Cell level fuses would save from some types of catastrophic fire causing failures, but then the whole system needs to be looked at in light of these fuses. Itâs not a clean winner. there are trade offs. I think it can make sense in a large pack with lots of extra space and a super smart BMS. I think it can cause more harm then good in small packs that are built like non-cell-fused back in all other ways.
I like how in @bevilacquaâs pack the fuses are mostly visible to the naked eye. One of the âbadâ things about cell level fusing is, itâs hard to tell if a fuse disconnected. Being able to see it is not foolproof but it helps.
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Cell fusing would save from overcurrent or short or internal short. The bad thing is that if one fuse blows on such small pack, that current will be pulled from smaller count of cells which will cause chain reaction. Not a problem of 2 cells blowing in couple hundred cell p group, but pulling 40A from 4 cells, 2 blown fuses means twice the current for remaining cells and in unlikely situation where the fuses dont blow on remaining cells or cell caused by increased current, you might light up the whole pack on fire
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Actually it would be the opposite. If right fuse(rated for right current) is used then, the fuses would just burn out and prevent the cells from over current.
Although it might be dangerous to suddenly lose battery while riding, but then you get to save your pack. What would be ideal is for the bms too somehow detect that the fuse has melted and warn us to make repairs.
For me itâs mostly about this thread
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The bms just needs to monitor Ah in the p group and it will know when a cell has disconnected
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even my Beestech BMS saved me once because of this. One of the cell holders broke and tore one fuse.
Was it the low voltage? Thatâs why discharge bmss need to be use with cell level fusing so that it can stop if they go out of balance
Yes, that was the case, I guess they do coulomb counting and correlate it to the lost voltage. It shut the pack of at around 3,4V/P-Group
I thought they just measured the voltage to cutoff. I didnât know âbasicâ bmss could detect amp hours
Itâs a discharge BMS, 2 of the 3P group cells were still connected so there is no other way to tell than doing C-Counting (on a simple way, I thinkâŚ)
I think we could possible be talking about two different things lol. I was saying that the bms detects its overdischarge limit by measuring the voltage of the cell. Thatâs why most say 2.8v cut off and such.
This means that if a fuse blows the bms will still stop that p group from over discharging because it will drain faster than the rest due to lower ah. Once hitting that LVC the bms stops all discharge.
An example of this is with power tools. You know when your drill battery is almost flat and you try to put in a screw or drill metal drawing high current and the drill cuts off. This is because the high current dips the voltage below the bms LVC and it turns off. However if you take it away from the load and try again it will still function but not with any loads applied.
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Thatâs what I actually said 
âunlikely situationâ. But people use resistor legs for fuses and other stuff that.
Looks very professional, like a pre built one. Congrats
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What are those tires? Hopefully not skull Board airless ones?
They are 
Heard bad stuff about them recently. No proper alignment thus Vibration