Method and structure for switching between two battery units for driving an electrically driven device

摘要

Electric apparatus, computer apparatus, controller, and battery switching method and program is provided to prevent a system shutdown caused by a reduction of electric power from a battery. A computer apparatus is constructed to be able to accept and be powered by a rechargeable main battery and a rechargeable sub-battery. An embedded controller in the computer apparatus monitors a remaining capacity at a pre-specified temperature of the sub-battery under discharge by receiving information from CPU. When the monitored temperature exceeds a predetermined temperature and when the monitored remaining capacity becomes less than a predetermined capacity, the embedded controller receives electric power from the main battery by switching the power supply circuit to provide power from the main battery instead of the sub-battery.