TP5100 Lithium Battery Charging Module.Double 8.4v /4.2v lithium rechargeable singleSize: 25 * 17 * 5mm ultra-small sizeInput voltage: 5-18V DC power supplyCharge status: full and unloaded bluelights, charging red.Programmable charge current. 0. 1A-2AProgrammable steady precharge current 10% -100%.Wide operating voltage, maximum reach I8VRed and green LED charge status indicatorChip temperature protection, overcurrent protection,undervoltage protectionBattery temperature protection, reverse battery shutdown,short circuit protectionSwitching frequency 400Khz, usable inductance 2OuH andmorePWR_ON Power battery for switching controlStatic input supply voltage (VIN): 20VBAI: -8.4V-20VBAT Short-Circuit Duration: ContinuousOperating environment Temperature range: -40 ° -85Storage temperature range: -65 ° - 12Packaging Include: 1Piece TP5100 Lithium BatteryCharging Module