A nickel metal hydride battery (nickel metal hydride battery) is a rechargeable battery. The chemical reaction of the positive electrode is similar to that of a nickel-cadmium battery (NiCd), both of which use nickel oxide hydroxide (NiOOH). Ni-MH batteries are divided into high-voltage nickel-hydrogen batteries and low-voltage nickel-hydrogen batteries.
A. Low-voltage Ni-MH batteries have the following characteristics:
(1) The battery voltage is 1.2~1.3V, which is equivalent to nickel-cadmium batteries;
(2) High energy density, more than 1.5 times that of cadmium-nickel batteries;
(3) It can be charged and discharged quickly and has good low temperature performance;
(4) It can be sealed and has strong resistance to overcharge and discharge;
(5) No dendrites are generated, which can prevent short circuits in the battery;
(6) Safe and reliable, no pollution to the environment, no memory effect, etc.
B. High-voltage nickel-metal hydride batteries have the following characteristics:
(1) Strong reliability. It has better over-discharge and over-charge protection, can withstand higher charge-discharge rates and has no dendrite formation. Has good specific characteristics. Its mass specific capacity is 60A·h/kg, which is 5 times that of cadmium-nickel batteries.
(2) Long cycle life, up to thousands of times.
(3) Compared with nickel-cadmium batteries, it is fully sealed and less maintenance.
(4) Excellent low temperature performance, the capacity does not change significantly at -10°C.