A mobile terminal having one or more of the following modes: a standby mode, talk mode, send/receive mode, and read/write mode, includes a cell array being capable of providing a cell array power and a backup battery being capable of providing battery power. The mobile terminal has a power management system that when the mobile terminal enters standby mode and/or read/write mode, has the ability to supply the mobile terminal with only cell array power. The power management system further has, when the mobile terminal enters talk mode and/or send/receive mode, the ability to supply the mobile terminal with battery power and/or cell array power. In both events, the power management system has the ability to send any excess cell array power to recharge the battery.