Yep..the BMS works as a safety feature. It equals out the amps to all the cells inside used when 2 or more batteries are hooked together in delivering a charge. It prevents a fire if the battery overheats it will shut down. Same if the charge is too many amps in charging it will temporary shut it down. Same for overcharging the cells it will temporary shut down. If you were to tear the top of the battery off, it’s on the very top of all the cells with the positive and negative terminal wired to it then wired to the cell blocks inside.