Among all the secondary and rechargeable batteries that are available till date, NiMH batteries have been a popular name. The concept of commercialized hydrogen based rechargeable batteries was sought in 1960s but inability to store hydrogen in small cells was a big hindrance. In the mid 90s, technological achievement was unlocked and commercial production of NiMH batteries became possible.A single AA standard NiMH cell gives 1.2V of outputs and can serve for an average of 2-3 years. The efficiency of these cells is around 70-80% and remains constant for a long period of time. This is a prominent reason for mass popularity of these cells.