Low Power State To Avoid Battery Damage Due To Excessive Drain

Rechargeable batteries in portable devices can be damaged permanently and become unrecoverable when completely drained. Such a situation arises when a device is left idle for a long period of time. This disclosure describes techniques to prevent battery damage during extended idle periods. When an idle state is detected, a low power state is selected for the computing device based upon a battery state of charge. The selection of the state is based on a comparison of the measured remaining battery capacity with a predetermined threshold. If the battery state of charge meets the threshold, the computing device is placed into a hibernation state and an embedded controller (EC) is shut down to conserve battery power. If the battery state of charge does not meet the threshold, the computing device is placed into a sleep state. In the sleep state, the embedded controller periodically monitors the battery state of charge, and disconnects the battery if the battery state of charge falls below a critical level