A secondary battery device is provided, comprising: a secondary battery capable of being charged and discharged; a charger for charging the secondary battery, the charger operating in at least two operation modes including first and second operation modes ...

For charging a secondary battery, at least two operation modes including first and second operation modes, in which the secondary battery is charged to predetermined charge end voltages different from each other, are established. Both life and capacity of ...

An object is to limit temperature rise in a battery, which operates at ambient temperature, due to heat generated at an outside heat source mounted close to the battery. A hollow space is formed in a wall of a battery container or a heat insulating materia...