This is a combined Balance and Protection board for 4S packs of lithium ion cells.
I have “BMS” in the title because that’s what people search for but please note this type of protection board is NOT a charging board, you still need to use an appropriate CC+CV charger to charge packs, this handles balancing (within reason) and protection (over DISCHARGE current, over voltage, under voltage, and short circuit).
In terms of balancing, this is a top-of-charge balancer, at 4.2v on a cell a resistor is switched in parallel with the cell to bring it down/reduce charge, until it his 4.19v
In terms of protection, the cells are each protected from serious overvoltage by the classic DW01 ic, and also the pack as a whole is protected from over discharge (not charge) current, and short-circuit.
In theory the working current (that is, constant) is 30A for this module, and the over-current is about 75A (that is, you're going to trip it out at that).
Max cell volts: 4.28 +/- 0.05 V
Min cell volts: 2.55 +/- 0.08
Cell balance current: 60mA
Working current: 30A
Over current: 75+/-5A
The balance IC is the Hycon HY2215-BB3A, the protection IC is the DW01
I'm not going to tell you how to use this, if you are buying this, you already know what you are doing, or you shouldn't be playing with fire.
Never rely on just one thing to protect you, others, or your things, always have a backup plan - in other words, don't come crying to me if your quad plummets to earth in a spectacular flaming ball because a cheap Chinese balance+protection board blew a mosfet, I'd be happy to replace the board, the quad, not so much. Like any component from China, you assume some risk. Sorry I have to say that, but it's the world we live in :-/
All of our products are shipped from Christchurch, New Zealand using CourierPost for NZ, and Airmail for international.
