Scope: Nominal voltage of 3.6V, 3.7V lithium battery (including 18650,26650, polymer lithium battery) Charging voltage: 16.8V - 18.1V Continuous discharge current (upper limit): 40A (if the cooling environment is not good, please reduce the load current use) Continuous charge current (upper limit): 20A Enhanced version: for starting current below 80A, power 135W below the drill.(Not balanced function) Note:this item is Enhanced version Note 1: The successful start of the drill requires three 15C-20C power battery, or six 10C-15C power battery (ordinary 18650 can not start the drill!!). Note 2: strictly according to map wiring 0V, 4.2V, 8.4V, 12.6V, 16.8V, do not deliberately short circuit. Note 3: When the load of the brush motor is used, try to connect a non-polar capacitor (withstand voltage above 25V, capacity 10uF-100uF) to the motor's positive and negative terminals to prevent the reverse spike from the motor. Break the MOS tube. Note 4: 4 groups of batteries in series, please ensure that the voltage of each group of batteries, if not the same, please fill each battery separately and then use in series. The The Discharge test, the voltage drop faster battery that group is poor battery. Condition: Type:Electronic products Application:Computer Operating Temperature:-40-+85 Electronic products:For Arduino STM colour:green Material:PC+ metal size:5.5*4.4cm Package Contents: 1 * 4S 40A Li-ion Lithium Battery Protection Board