What is the difference between Nickel Cadmium (NiCd) batteries and Nickel Metal Hydride (NiMH) batteries?
Firstly there is no difference in the voltage of the cells; they both produce 1.2 volts per cell. NiCd batteries have less capacity but around three times more cycle life than NiMH Batteries. NiCd batteries are more suitable for high drain and fast charge appliances such as Cordless Power Tools and appliances running motors. Large capacity NiCds are still in use for Aviation, Solar Storage appliances, Emergency Generator Set Start and Theatre Lighting. The reputation of NiCds in these applications is one of reliability and longevity. NiMH batteries have a higher capacity to size ratio but only have around one third of the cycle life of a NiCd battery. If a NiMH battery is treated like a NiCd and deep discharged regularly it will not have a long lifespan. NiMH batteries are not known for having the ‘memory effect’ problems of NiCds. They are very suitable where higher capacity is required in appliances such as Mobile Cellular phones, Laptop Computers, Video Cameras and Hand Held Radios.
