6.1  Introduction     

• Definition: A battery is an energy storage device, which converts chemical energy directly to electrical energy.
  
  
• Non-Rechargeable: This is called a primary cell. Typical battery types being: Alkaline, carbon-zinc, certain lithium metal batteries, silver oxide and zinc air.
  
  
• Rechargeable: This is called a secondary cell. Typical types being: Lead-acid, lithium-ion, certain lithium metal batteries, nickel-cadmium and nickel-metal hydride.