A computer provided with an intelligent battery 52 for charging/discharging, the intelligent battery 52 supplying power to a main system unit, wherein the intelligent battery 52 includes: a voltage measuring circuit 70 for measuring a battery voltage of the intelligent battery 52; a current measuring circuit 63 for measuring a charging/discharging current of the intelligent battery 52; a temperature measuring circuit 90 for measuring a temperature of the intelligent battery 52; and a CPU 62 for periodically reading the battery voltage measured by the voltage measuring circuit 70, the charging/discharging current measured by the current measuring circuit 63, and the temperature measured by the temperature measuring circuit 90 so as to manage a capacity deterioration of the battery due to a storage deterioration and a cycle deterioration, and wherein the main system unit includes an embedded controller 41 for receiving information about the capacity deterioration from the CPU 62 of the battery.