Oh my
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I do not cut āallā strips. Only when necessary. Placing properly and protecting the wires is way more important than rounded corners. I also see many of you are making just two welds per cell. Thatās perfect for a dual suspension ebike but imho is scary for esk8. Our vibrations are really something. I make 6 welds per cell and stick every single balance wire with kapton and pad them with eva foam. Thereās no way they can be cut. Any part of the nickel can cut the wire even if they are rounded with the right movement/hit so I prepare my packs thinking on possible bumps.
Thatās just my opinion.
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Ya Iām with you. Cutting the nickel is the most time consuming part building my batteries! Some one needs to make a cutting jig asap!
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Lol, I really dont need to cut any of the nickel on this big block packā¦ but it looks so nice.
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This might be a really really dumb question, and please donāt be dissapointed in me.
Does the power supply voltage matter? Iām currently looking at power supplies, but the ones that are 50.4v and over 2a are kind of expensive.
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You mean āpower supplyā as one to be used for a balance charger or you actually mean a āli-ion chargerā? If the latter, the voltage does matter and it must match your battery pack voltage, e.g. you need 50.4V one for a 12S pack; 42V one for 10S pack etc.
I mean a power supply that connects to the charging port that is connected to the BMS.
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Right, that would actually be the li-ion charger. It has to be able to switch from CC to CV mode as the battery pack voltage gets close to the target voltage.
The Yzpower chargers are popular and inexpensive. I have this 4A one for $27 shipped and it works well: https://www.aliexpress.com/item/32864844991.html. It only really does 3.7A but thatās still good enough for me.
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I have already ordered the charging port, so i want the 5.5x2.1 mm plug.
Would this charger also work, even though itās only 2a?
Yes, it should work as long as you have a 12S battery pack. I have a similar one, too. It only does a little over 1A and it gets really hot but it hasnāt failed me yet.
Note that the Yzpower charger I linked can also be ordered with the 5.5x2.5mm plug and would be a much better value for the money unless you prefer to charge your battery pack very slowly (which is not necessarily a bad idea if you donāt mind the longer charging time).
Oh, sorry I didnāt realise it could be ordered with other plugs, Iāll go for the aliexpress one.
Thank you for the help
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thanks for the advice Im in the process of geting a charger aswell, but why do you need a CC/CV if you are using a bms? Doesnt the bms handle the charging bit aslong as it has a powersupply?
No. It only takes care of balancing the cells. It can also cut off the charger should it be unsafe to continue charging (e.g. one or more cells are about to get overcharged). The charging itself is left up to the charger though so the CC/CV is necessary.
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Okay. So the bms have no part in limiting the current to the battery during charging? Only cuting the current off to balance individual cells and then resuming if it isnt fully charged?
the bms does, but only in the way of cut off if there is an overcurrent. A bms doesnĀ“t activly influence the charge current, that is done only by your charger (depending on your charger)
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Think of it as you charger dose the bulk of the work filing the tank up and the BMS micromanages every thing else inclining protections
Both should cut of from overcharging
Charger by dropping the curent down slowly
BMS by stoping over voltage
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Is there a difference when charging the battery fast vs slow in terms of battery health and lifetime?
There are ways to increase battery health charging slower, charging to a lower voltage than max, discharging slower, ending discharge befor min voltage.
I recommend you stick to manufacture recommendations limits that spend a lot of time testing to work out the best compromise.
need some help with 12s6p. battery will not charge. when i got to work i put the board on charge it charged for 5 min then started blinking red/green. I unplugged the charger and power on the board to check the battery level. the battery was at 40%. I powered the board off and plugged the charger in. It charged to 49.7v. after work i went on an after work ride check voltage every mile or so. I kept getting weird cutoff like behavior. made it home and checked voltage it said 40%. when i started charging it charged for 5 mins then started blinking red/green. i checked the voltage it said 3% on metr pro and 16% in Unity app. checked voltage from the xt60 on battery it says 41.9v the charger reads 50.5v. any ideas?
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