Specifications: Voltage Charge Voltage 19/21V Single Cell Charge Voltage 3.8/4.25V Current Continuous Discharge Current 8-20A Overcharge Protection Overcharge Single Cell Detection Voltage 3.85-4.25V Overcharge Protection Delay 1S Overcharge Single Cell Recovery Voltage 3.75-4.13V Overcharge Protection Release Delay 1mS Over-discharge Protection Over-discharge Single Cell Detection Voltage 2-2.8V Over-discharge Protection Delay 1S Over-discharge Single Cell Recovery Voltage 2.5-3.0V Over-discharge Protection Release Delay 10020mS Over-current Protection Over-current Detection Voltage 0.1-0.4V Over-current Detection Current 305A Over-current Detection Delay 1S Recovery State Auto Short Circuit Protection Support Yes Short Circuit Detection Delay 250uS Short Circuit Release Delay 1S Short Circuit Detection Voltage 0.8V Recovery State Auto after Disconnect Load Over Temperature Protection Protection Temperature 705 Recovery Temperature 555 Power Consumption Working State 25uA (25) Stand-by State 6uA(25) Internal Resistance Discharge Main Circuit Internal Resistance 305m Temperature Operating Temperature -40-85 RH75% Store Temperature -40-125 RH75% Size Length*Width 46*40mm/1.81*1.57" Package Includes: 1 x Protection Board