The key difference between primary cells and secondary cells is reusability. Secondary cells can be reused repeatedly, while the primary cells can only be used once. Primary cells should not be recharged because it is dangerous to attempt recharge and may explode.
Primary cells are typically found in electric toys, clocks, wristwatches, and domestic remote controllers. Secondary cells are also chemical cells, but they may be restored for reuse. The chemical reaction which generates electricity is reversible, and the cell can be utilized as a new one after it is recharged.
The cell can be used again, but the lifetime is lessened. A common use for secondary batteries includes starting, lighting, and igniting vehicles. They are also used in power supplies, telecommunications, and tools.