HW-391 2S 20A 7.4V 8.4V Li-ion Lithium Battery Charger Protection Board 18650 BMS Board Module Balance _x005f_x000D_ Specification: _x005f_x000D_ Charging voltage: DC8.4-9V _x005f_x000D_ Continuous discharge current: Maximum 20A (if the heat dissipation is not good, please reduce the load current to use) _x005f_x000D_ Continuous charging current: Maximum 10A _x005f_x000D_ Applicable options: Suitable for lithium batteries with a nominal voltage of 3.7V and a full charge of 4.2V (including 18650, 26650, polymer lithium batteries), with a starting current of 25A, power drills below 50W, or 168W resistive load. _x005f_x000D_ Product size: 48*20*3mm _x005f_x000D_ Product weight: 5g _x005f_x000D_ Packing size: 50*50*15mm _x005f_x000D_ Package weight: 5g _x005f_x000D_ _x005f_x000D_ Precautions: _x005f_x000D_ 1. To successfully start the electric drill, you need 2 10C-20CD power batteries, or 4 51-10C power batteries (recommended power battery models: for compatible with sony vtc4A, vtc5, vtc6) OV and 8.4V connection lines, use more than 2 square millimeters Copper wire (nickel sheets cannot be used). _x005f_x000D_ 2. When welding the battery for the first time, it needs to be charged before output. Accord connects OV, 4.2V, 8.4V according to the figure. _x005f_x000D_ 3. When the battery is being welded for the first time or is being charged, as long as a single battery exceeds 4.2V, the "430" resistor will heat up and discharge (discharge to about 4.19V to stop heating). If the "430" resistor is very hot, please check whether it is connected to the wrong wire. _x005f_x000D_ _x005f_x000D_ Note: _x005f_x000D_ Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! _x005f_x000D_ Please allow 1-2mm measuring deviation due to manual measurement. _x005f_x000D_ _x005f_x000D_ Included: _x005f_x000D_ 1 X Lithium Battery Protection Board