Patent ID: 7353894

Claim:
A hybrid electric vehicle comprising: an internal combustion engine; a plurality of sealed nickel-metal hydride storage cells, each of the storage cells comprising: a positive electrode comprising nickel as a positive electrode active material; a negative electrode comprising a hydrogen-absorbing alloy as a negative electrode active material, the negative electrode having a theoretical capacity larger than a theoretical capacity of the positive electrode so as to provide a charge reserve capacity when the positive electrode is in a fully charged state and to provide a discharge reserve capacity when the positive electrode is in a fully discharged state, a ratio of the charge reserve capacity to the discharge reserve capacity ranging from 1:0 to 1:0.5; a separator interposed between the positive electrode and the negative electrode; and an electrolyte immersing therein the positive electrode and the negative electrode; a generator driven by the engine to generate electricity for charging the storage cells; and a controller that controls the engine and the generator to recharge the storage cells.