A controller, comprising: a control unit that is configured to acquire historical information of an electrical storage unit from a storage unit (36, 47), the electrical storage unit including one or two or more storage batteries, wherein the control unit is configured to perform a control of: setting a charging setting voltage value of the electrical storage unit to a typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the typical-charging voltage value; and in case where the historical information satisfies a voltage changing condition, changing the charging setting voltage value of the electrical storage unit to a low-charging voltage value lower than the typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the low-charging voltage value, wherein the voltage changing condition is at least one of a condition in which the number of charging and discharging cycles, which are performed with the typical-charging voltage value, in the electrical storage unit is greater than a predetermined number of cycles, a condition in which out-of-temperature-range accumulated time, for which the electrical storage unit is used out of a typical-use temperature range, is greater than a threshold value, a condition in which internal resistance is greater than a predetermined value, a condition in which full-charging capacity is reduced from initial capacity by a predetermined value, and a condition of exceeding over passed accumulated time that is predicted by lifespan prediction, characterized in that the control unit is configured to perform a control of, after the electrical storage unit has performed charging and discharging with the low-charging voltage value, returning the charging setting voltage value of the electrical storage unit to the typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the typical-charging voltage value. a control unit that is configured to acquire historical information of an electrical storage unit from a storage unit (36, 47), the electrical storage unit including one or two or more storage batteries, wherein the control unit is configured to perform a control of: setting a charging setting voltage value of the electrical storage unit to a typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the typical-charging voltage value; and in case where the historical information satisfies a voltage changing condition, changing the charging setting voltage value of the electrical storage unit to a low-charging voltage value lower than the typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the low-charging voltage value, setting a charging setting voltage value of the electrical storage unit to a typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the typical-charging voltage value; and in case where the historical information satisfies a voltage changing condition, changing the charging setting voltage value of the electrical storage unit to a low-charging voltage value lower than the typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the low-charging voltage value, wherein the voltage changing condition is at least one of a condition in which the number of charging and discharging cycles, which are performed with the typical-charging voltage value, in the electrical storage unit is greater than a predetermined number of cycles, a condition in which out-of-temperature-range accumulated time, for which the electrical storage unit is used out of a typical-use temperature range, is greater than a threshold value, a condition in which internal resistance is greater than a predetermined value, a condition in which full-charging capacity is reduced from initial capacity by a predetermined value, and a condition of exceeding over passed accumulated time that is predicted by lifespan prediction, characterized in that the control unit is configured to perform a control of, after the electrical storage unit has performed charging and discharging with the low-charging voltage value, returning the charging setting voltage value of the electrical storage unit to the typical-charging voltage value so that the electrical storage unit can perform charging and discharging with the typical-charging voltage value.