nikkelmetálhidrid

Nikkelmetálhidrid, often abbreviated as NiMH, is a type of rechargeable battery technology. These batteries use a positive electrode made of nickel oxyhydroxide and a negative electrode made of a hydrogen-absorbing alloy, typically a mischmetal containing rare earth elements like lanthanum, cerium, and neodymium, along with nickel. During discharge, hydrogen is released from the negative electrode and combines with nickel oxyhydroxide at the positive electrode. The reverse occurs during charging, where hydrogen is absorbed by the negative electrode and nickel oxyhydroxide is reduced.

NiMH batteries offer a higher energy density compared to older nickel-cadmium (NiCd) batteries, meaning they can store more energy for their size and weight. They also exhibit a lower self-discharge rate, retaining their charge for longer periods when not in use. A significant advantage of NiMH technology is its environmental friendliness; unlike NiCd batteries, they do not contain toxic cadmium. This makes them a popular choice for a wide range of applications, including portable electronics, electric and hybrid vehicles, and power tools. However, NiMH batteries can be sensitive to overcharging and extreme temperatures, which can degrade their performance and lifespan.