Nickel-Metal Hydride Batteries
They represent the evolution Ni-Cd cells and after many years of refinement they reached a reliability entirely similar.
They are available in the following shapes:
and for the following use:
- permanent charge
- high discharge
They can be used for a wide range of applications, within the limits of their energy density, that reaches max 70 Wh/ Kg
The cells are completely sealed and require no maintenance.
They can be stored and used in any position.
Every cell is equipped with a safety and reversible valve that vents an over-pressure who may develop as a result of malfunctioning.
The basic structure is identical Ni-Cd batteries.
Ni-MH batteries consist of a positive pole containing nickel hydroxide as a main active material, a negative pole composed by a mixture of rare earth and alloys who can absorb and release the high density hydrogen ion, a separator made by thin synthetic fibers, an alkaline electrolyte, a metal case hermetically closed and equipped with a safety valve.
You can see the construction of a cylindrical cell Ni-MH in the drawing below.