Abstract: A battery charger with a self-contained power source which provides a current charging signal at or near the resonant frequency of the battery to be charged when no other power supply is readily available. A storage energy device, for example a battery, delivers a current charging signal modulated at or near the resonant frequency of a load, or stores energy from a source.

Abstract: A signature connector adapter adapted to provide additional capabilities for a battery charger beyond not only charge batteries, but performing other user-friendly functions is presented. One embodiment utilizes a resistor disposed within a signature charger adapter to detect battery type and communicate the battery type to the battery charger. The signature connector adapter provides information such as, but not limited to, battery chemistry, battery voltage, charging capabilities, and thermal limits. The battery charger can then optimize charging performance. The signature connector adapter allows a plurality of household, construction, medical and military devices to be charged and/or powered via the battery charger.