US Patent 11283294 Wireless charging for rechargeable button cell battery

The present invention provides a charging device for a button/coin cell rechargeable lithium ion battery. A receiving inductor coil receives energy from a transmitting inductor coil which is passed to a wireless charging receiving circuit which is in electrical communication with the receiving inductor coil. The wireless charging receiving circuit communicates with a charging control circuit, a voltage regulation circuit, and a battery protection circuit in electrical communication with one another. The voltage regulation circuit includes a 1.8 V to 3.3 V constant voltage output regulator circuit to maintain a constant voltage output in loading currents ranging from approximately 10 μA to approximately 300 mA.