To improve the charging and discharging efficiency of a secondary battery provided on a hybrid vehicle, and to prolong the lifetime of the battery.

When required power is increased by pressing down an accelerator pedal 82 while a secondary battery 44 is charged with a front-wheel motor 40 driven as a generator, an increment of the required power is outputted from a rear-wheel motor 90, using electric power from the front-wheel motor 40, if the increase of the required power is within the range of charging power that is used for charging the battery 44. This battery 44 is charged continuously, while the charging power decreases, so that less frequent changeovers for the charging and the discharging can suppress temperature rise in the battery 44. As a result, the charging and discharging efficiency of the battery 44 can be improved, and its lifetime can be prolonged.

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