Modern acid batteries and plates Pb, are embodiment of simplicity in use. Unlike NiCd batteries, they must be recharged by connecting to a constant voltage. In this situation, the loading current will provide a good indication of the state of loading.

Here are two battery chargers using solar cells to capture light energy for battery charging. It converts light energy into electrical energy. Simple and ideal energy saving designs.

Here is an ideal Mobile charger using 1.5 volt pen cells to charge mobile phone while traveling. It can replenish cell phone battery three or four times in places where AC power is not available.

Simple High Current battery charger using raw DC for charging
D.Mohan Kumar