This is simple to make and low cost emergency light. also it gives better backup more than 3 Hour.
low cost and simplicity comes by replacing the battery charger circuit with a any mobile charger, here the connector CN1 must be socket of any mobile charger here me used nokia's charger pin convertor.
The output voltage of most of mobiles will be in 5-7 Volts thus it is suitable for 4.8V batteries. LED D5 acts as charging indicator. while connecting LEDs in parallel all must be same type (same batch).
