This is a intelligent 12V battery charger controller. you can use your old 12V power supply to charge a battery. its automatically off the connection when the battery is fully charge.
Specifications
Battery Type
12V Battery ( Lead acid, Li-ion)
Input Voltage
13.8V ~ 14.8V
Length x Width x Height
65mm x 52mm x 30mm
Special Features
DC voltmeter connection
Voltage
Relay closing voltage - 12.4V
Relay off voltage: 14.8V