An alarm system with improved power is provided. The improved power comprises at least two batteries. Each battery has the capacity to individually back up the alarm system for a standby period. The alarm system selects either battery and operates from that battery. A switching network is coupled to a power source and to the batteries. The switching network is capable of transferring one battery to charge and the other battery to discharge, with the discharge battery providing power to the alarm system. A battery charger circuit is powered from a power source. The battery charger circuit is used to charge the battery that is not powering the alarm system. Circuitry and software can be provided to monitor the health of the batteries.