Patent ID: 8963485
Filing Date: 2015-02-24
Classification: H02J

Abstract:
1. A battery charger for increasing a charge of a rechargeable battery, the battery charger comprising: (a) an input for an electric charging power source configured to supply electrical charging power to the rechargeable battery via an output circuit portion interposed therebetween, the output circuit portion having a predetermined reference voltage associated therewith; (b) a transfer function circuit portion configured to sense the voltage of the rechargeable battery as a sensing voltage, wherein a change in the sensing voltage is directly proportional to the internal impedance of the rechargeable battery; (c) a control logic circuit portion configured to select between: (d) a compensation circuit portion disposed between the control logic circuit portion and the output circuit portion, the compensation circuit portion configured to generate the change in the sensing voltage thereacross in the constant current, scalable voltage operational mode; wherein the constant current, variable voltage operational mode is configured to drive the output circuit portion to provide a constant current, variable voltage electrical charging power to the rechargeable battery by setting the variable resistor to an initial value until the sensing voltage is equal to the predetermined reference voltage; the constant current, scalable voltage operational mode is configured to drive the output circuit portion to provide a constant current, scalable electric charging power to the rechargeable battery in response to the sensing voltage exceeding the predetermined reference voltage, the scalable voltage being scaled to the change in the sensing voltage by increasing the value of the variable resistor; and the variable current, constant voltage operational mode is configured to drive the output circuit portion to provide a variable current, constant voltage electric charging power to the rechargeable battery in response to the sensing voltage exceeding a comparison voltage by stopping the increase of the variable resistor.