Patent ID: 8410751

Claim:
A combination comprising: a battery housing device housing an internal battery, the battery housing device having a receiving coil that supplies charging power to the internal battery; and a charging pad having a transmitting coil that magnetically couples with the receiving coil of the battery housing device and supplies charging power, wherein the battery housing device further comprises a modulator circuit that modulates the impedance of the receiving coil with internal battery information, wherein the charging pad further comprises a detection circuit that detects battery information via the transmitting coil by detecting receiving coil impedance changes made by the modulator circuit, wherein the modulator circuit comprises a control circuit and a load circuit connected in parallel with the receiving coil, the load circuit having a switching device connected in series with an impedance modulating capacitor, and the control circuit switches the load circuit switching device ON and OFF in accordance with battery information, wherein the modulator circuit switches the switching device ON and OFF to transmit battery information to the charging pad, and wherein the battery housing device further comprises a battery data detection circuit that detects internal battery information, the battery data detection circuit being connected between the internal battery and the modulator circuit.