Premier Engineered Products Corporation

Electrodynamics, Inc.

Jeffrey A Rose

Joseph A Cates

Stephen D Rose

A disengageable electrical capacitive coupling for transmitting high frequency AC electrical current is provided. In an electric vehicle charging system, dual first connectors form the vehicle inlet, and mating dual second connectors form the coupler. A dielectric material, such as barium titanium oxide, is positioned between the connectors to form capacitors. A holder secures the connectors together with the dielectric material in between. The interface formed is sufficient for establishing a highly efficient, compact electrostatic field for transmitting the current. Provision is made in the holder for easily disengaging the connectors once the charging cycle is complete. When utilized as a charging system, the capacitive charge coupling is connected between a high frequency drive unit on the charger side and a DC power conversion unit on the energy storage side, such as in an electric vehicle. In an alternative embodiment, the connectors comprise mating multiple section conductive plates formed of a spring metal core with a flexible dielectric coating, such as polypropylene. Variation of the various parameters of the charge coupling is utilized to enhance the power transfer capability.

Capacitive charge coupling with dual connector assemblies and charging

A method and apparatus is provided to charge a battery including a DC charge current supply having a variable output. The charging current is varied in accordance with several sensed parameters in the circuit so that battery voltage is accurately controlled. Initially, constant charging current is applied, and upon detecting that battery voltage increases to the gassing voltage, an incremental step reduction in charging current is triggered. The step reduction causes a decrease in battery voltage, dropping it below the gassing voltage. The step reduced charging current is then applied to increase battery voltage back up to the gassing voltage, thereby triggering another step reduction in charging current. This process is repeated multiple times providing a stepped current profile, i.e., each battery voltage increase to the gassing voltage triggering a step reduction in charging current, and in turn a corresponding voltage reduction. The battery voltage, with the alternating increases and decreases, is thus defined by a saw-tooth profile with peaks at the gassing voltage. When the charging current is finally reduced to a minimum level, the sensed battery voltage triggers a termination of the stepped current reduction. Upon the battery reaching full charge, the application of charging current is terminated. In the alternative embodiment, the slope of the voltage curve is detected and analyzed to control a step up profile of the current during the initial phase of charging. The rising temperature of the battery controls a decrease in the gassing or target voltage.

Battery charging method with stepped current profile with operating

A method and apparatus is provided to charge a battery including a DC charge current supply having a variable output. The charging current is varied in accordance with several sensed parameters in the circuit so that battery voltage is accurately controlled. Initially, constant charging current is applied, and upon detecting that battery voltage increases to the gassing voltage, an incremental step reduction in charging current is triggered. The step reduction causes a decrease in battery voltage, dropping it below the gassing voltage. The step reduced charging current is then applied to increase battery voltage back up to the gassing voltage, thereby triggering another step reduction in charging current. This process is repeated multiple times providing a stepped current profile, i.e., each battery voltage increase to the gassing voltage triggering a step reduction in charging current, and in turn a corresponding voltage reduction. The battery voltage, with the alternating increases and decreases, is thus defined by a saw-tooth profile with peaks at the gassing voltage. When the charging current is finally reduced to a minimum level, the sensed battery voltage triggers a termination of the stepped current reduction. Upon the battery reaching full charge, the application of charging current is terminated.

Growing community of inventors

La Jolla, CA, United States of America

Jeffrey A Rose