ah ok cant remeber who it was that told that to me
sorry will correct my post
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I have to confess every time I wanted a fuse for the charging circuit I went on amazon and only found these ones and ended up not fusing it at all 
Very interested on what you guys use specifically.
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I use âefusesâ, electronic fuses that use MOSFETs to switch the current on/off much faster and more precisely (at very particular current levels and timing). Iâm sure others will chime in with their recommendations for standard fuses though.
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ah nice and can you just reset those when they blow?
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Check Digi-Key, Newark, Allied Elec, and other dedicated component suppliers. Amazon is not the place to shop for these. 
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SelectableâŚyou can button reset or they will automatically reset.
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how large are they? can you link
They are a chip you have to design a circuit around. Multiple manufacturers make them but I use ones from TI: https://www.ti.com/power-management/power-switches/efuse-hotswap-controllers/overview.html
Much bigger and more expensive than just a regular fuse though. But you get a lot more control and functionality for the size and cost.
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A polyfuse might also be an option.
(Is used for lower voltage and current mostly)
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OohhhhâŚwaitâŚI goofed. You have a 12S pack at high amps. I donât think they have an efuse that will work for you. Check the hot swap controllers.
I use the efuses mostly for lower voltage or lower current levels.
Check Analog Devices too: https://www.analog.com/en/parametricsearch/11394#/
The LTC4368 is the type of chip that can protect a 12S pack.
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No you didnât, only interested for charging, so a limit around 10 to 15A.
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I was just looking into that earlier today. The 60V ones I found topped out at 5A. 
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Yup! This isnât the neatest work but you can see no cross overs (there are but itâs in free space so they will not rub under pressure)
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Really clever, it is not an easy layout to do.
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Haha itâs a bit of brain work, it took me a second round because 2 wires got mixed, but thatâs why you solder with the balance connector out and check the pins to see if itâs right
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Itâs going to depend a lot based on the pack size. It just might balance a .1V for a 4Ah pack, but I wouldnât be to sure.
My thoughts here are that youâre correct, itâs not going to happen.
If you look at the balance current on most BMSâs is 25-35mA. Now imagine trying to balance a .1V difference on a 16Ah pack. That would take literal days. The only BMSâs Iâve ever seen that can do that are LLT smart BMSâs because you put them in static balance and it just goes until it hits the programmed delta.
It also doesnât help that most of us use 4-8A chargers. So itâs going to blast right up to full voltage. If you had a charger that was maybe .5A and used that from 4-4.2V charging it would take a lot longer and might buy the BMS more time to balance out the pack a bit extra.
But on large packs, +6P or more, and the higher you go the more ineffective standard BMSâs become at balancing to the point it probably isnât worth even using them and instead smart BMS option or as some have done, adding a lipo balance charger hookup in which can balance at amps instead of milliamps and actually keep a large capacity pack well maintained.
Here is the full DALY Data Sheet for a 12S 15A BMS
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on llt in theory could you just stick in static balance on a some rainy days and leave to balance for a couple days?
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Correct, thatâs what I do on the first startup of an LLT bms in a pack. charge to 4V, lower the balance start to 3.8V, lower the voltage delta to .01, and flip it to static. Then work on putting the rest of the board together. Usually overnight the pack will be balanced to that spec since new cells are generally already close. Then I put it to charge balance and set the voltage start to 4V. I check it every so often and flip to static if needed.
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Do the tiny Daly BMSes even have a balance function?
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