Initial chargingcurrent less than 2.1 A Voltage 14.4V~15.0V at 25ºC (77ºF) Temperature Coefficient -30mV/ºC Standby: Voltage 13.5V~13.80V at 25ºC (77ºF) Temperature Coefficient -20mV/ºC It is recommendedto use constant-voltage charge andrecharge immediately after use.