NiCd is a type of rechargeable battery that uses nickel oxide hydroxide and cadmium as electrodes. Widely used in applications such as power tools, they have a high discharge rate but have low capacity compared to other rechargeable batteries.
There are two types of NiCd batteries: sealed and vented with the most common type being sealed. These batteries differ from the NiMh batteries because it uses cadmium as it’s negative electrode.
Up until the mid 1990’s, the NiCd batteries were the most popular in consumer electronics. Recently the NiMh and Li-Ion batteries have become more readily available and are cheaper. However the NiCd battery is still the preferred choice of batteries in certain high discharge applications (i.e. power tools) because it can endure the discharge with no damage or loss of capacity.