Nickel Metal-Hydride (Ni-MH)
Nickel-metal hydride cells have an anode (negative) in a metal alloy capable of absorbing and desorbing hydrogen, plus a nickel hydroxide cathode (positive), immersed in an alkaline electrolyte solution of potassium, sodium and lithium hydroxides. Nickel-metal hydride cells are rechargeable and deliver a voltage of 1.2 V.
This kind of cell can be sealed, in smaller capacities (< 60 Ah), or open, in larger capacities (> 60 Ah). The cells are maintenance-free but require precise charge level monitoring, to control gaseous exchanges with the outside and thus water consumption (for open cells, only slightly pressurized, owing to size). Charge monitoring also helps minimize heating under charge, to maximize capacity and service life.
Sealed cells are in cylindrical shape with nickel steel can and open cells are prismatic in shape, with casing in flame retardant plastic, with fluid circulation for temperature control.
Nickel-metal hydride cells have very similar properties to nickel-cadmium units, and share the same manufacturing processes and most components, except of course the hydridable anode material. They have excellent energy density by volume (up to 140 Wh/L) and are ideal for high-capacity maintenance-free units.
Sealed cells are used in many mobile and fixed professional and industrial applications. Open cells are used for traction and back-up power in public transport (trams, trains) and industrial vehicles, in stationary back-up systems and in photovoltaic applications.
VH / VHT / VHT U - Super high power series
- personal mobility
- professional tooling
- medical equipment
- personal care
- emergency lighting units
- UPS and back-up systems
- professional lighting
- radio communication and tracking equipment
- military equipment
- professional electronic devices