Universal Battery Charger for Charging up to 18V Cell

Universal Battery Charger for Charging up to 18V Cell
This universal battery charger has regulated output voltage which can be adjusted as you need. Also, this circuit has an adjustable constant-current charging circuit.  So, the circuit will be compatible and easy to use with the most NiCad batteries.  It capable to charge a single cell or a number of series-connected cells up to a maximum of 18V. A series connection of power transistors T1 and T2 to manage the battery charger's output voltage and charge-current rate. An LM317