About secondary cells batteries
Secondary cells :
These are also called as storage cells or accumulators. In these cells the chemicals can be brought back to their initial state by charging the exhausted cell with electric current from an external source. Thus, the secondary cells can be used again and again by changing them. The electrical energy can be stored in these cells and these cells are called storage cells accumulators. The lead storage battery (or Acid storage cell) nickel - cadmium storage cells, and alkali storage cell (or, the Edison accumulator) are the secondary cells.