What is Nickel-metal hydride battery?
[[File:Two GP950 AAA NiMH batteries.jpg|thumb|Nickel metal-hydride batteries]] A '''nickel-metal hydride battery''', also known as '''NiMH''', is a secondary cell, meaning it is a [[rechargeable battery]]. They are used in [[camera]]s and other electronic devices. They are made in several sizes; AA is the most common. They are similar to nickel-cadmium batteries but store twice as much energy. They have a voltage of 1.2 V, the same as the nickel-cadmium battery. They do not contain toxic chemicals like the [[nickel cadmium battery]] does. They work by the [[oxidation]] of [[hydride]]s, such as [[lanthanum]] hydride, by [[nickel(III) oxide]]. They have longer [[shelf life]] and are more durable than the [[lithium-ion battery]]. They are not as powerful for their size, although the best Ni-MH batteries are very close. They used to be more expensive than nickel cadmium batteries, but in the 21st century the cost is similar. ==Related pages== * [[Nickel(III) oxide]] * [[Secondary cell]] * [[Table of batteries]] {{science-stub}} [[Category:Batteries]]