A control method for a bi-directional DC/DC converter. A source terminal transmits electric energy to a destination terminal sequentially through a first rectifier module and a second rectifier module of the converter. The method includes obtaining a first voltage value output by the first rectifier module in a current control cycle, obtaining a second voltage value output by the second rectifier module in the current control cycle, calculating a theoretical voltage control quantity of the bi-directional DC/DC converter in the current control cycle based on a preset reference voltage value and the second voltage value, and setting an actual output voltage of the bi-directional DC/DC converter in a next control cycle based on the theoretical voltage control quantity and the first voltage value.

An apparatus and method for diagnosing whether a charging and discharging switching element provided on a charging and discharging path of a battery pack operates normally. A charging and discharging switching unit having a charging and discharging switch and a fuse is installed on a charging and discharging path between a battery cell and a pack terminal. The apparatus includes a first diagnosing path a second diagnosing path, a third diagnosing path, an integrated diagnosing path having a diagnosis switching unit and a diagnosis resistor, a voltage measuring unit, and a control unit configured to turn on and off the diagnosis switching unit and determine whether the charging and discharging switching unit is operating abnormally based on the diagnosis voltage measured by the voltage measuring unit.

A power apparatus applied in a solid state transformer structure includes an AC-to-DC conversion unit, a first DC bus, and a plurality of bi-directional DC conversion units. First sides of the bi-directional DC conversion units are coupled to the first DC bus. Second sides of the bi-directional DC conversion units are configured to form at least one second DC bus, and the number of the at least one second DC bus is a bus number. The bi-directional DC conversion units receive a bus voltage of the first DC bus and convert the bus voltage into at least one DC voltage, or the bi-directional DC conversion units receive at least one external DC voltage and convert the at least one external DC voltage into the bus voltage.

A microgrid system controller includes a regulated bus, a variable-frequency drive (VFD) inverter, a generator coupled to a rotatable flywheel, a resistive load; and a plurality of actuatable switches. The microgrid system controller may also include a battery and charge controller or a battery storage device. The plurality of actuatable switches couple some of the various components.

This application discloses an apparatus and a method for detecting internal resistance of a battery, applied to the field of intelligent vehicles. The apparatus includes: a processing circuit, a differential amplifier, and a charging circuit. The processing circuit is configured to input a first comparison voltage to a second input end of the differential amplifier and maintain the first comparison voltage. The differential amplifier is configured to output a first output voltage based on the first detection voltage and the first comparison voltage. The processing circuit is further configured to control the charging circuit to charge the battery by using a constant current, and detect a second detection voltage of the battery after the battery is charged. The differential amplifier is further configured to output a second output voltage based on the second detection voltage and the first comparison voltage.

A semiconductor device that is of a face-down mounted chip-size package type, discharges electric charges stored in an electric storage device (battery), and has a power loss area ratio of at least 0.4 (W/mm.sup.2) obtained by dividing a power loss (W) in the semiconductor device at time of the discharge by an area (mm.sup.2) of the semiconductor device, the semiconductor device comprising: a field-effect transistor of a horizontal type and a resistor that are connected in series in stated order between an inflow terminal and an outflow terminal; and a control circuit that causes a discharge current to be constant without depending on an applied voltage between the inflow terminal and the outflow terminal. A difference between a maximum temperature of a field-effect transistor portion and a temperature of a resistor portion is within five degrees Celsius in a discharge period.

A combined battery charger and engine jump start system configured to automatically determine in which operating mode to operate based on the output plug attached to an output outlet is disclosed. For instance, the system may include a single output outlet and a single cable capable of being attached to the single output outlet in multiple positions to enable the system to automatically operate in the correct mode. In another embodiment, the system may include a single output outlet and a cable for a battery charger process and a cable for an engine jump start process whereby a cable position or plug configuration enables the system to automatically operate in the correct mode. As such, the system is more cost effective to manufacture and more reliable in that the system is automatically places itself in the correct operating mode when a cable is attached thereto.

An electrical generator is provided. The electrical generator can include a generator, an electric motor, and a battery. The generator has a rotatable shaft and stationary component and be operatively coupled via a drive belt to the motor, which provides torque to the rotatable shaft of the generator The battery is operatively coupled to the motor. The generator can be operatively coupled to a utility grid via a transformer/invertor that can import current from the utility grid to charge the battery when the utility grid is operating and export current from the generator to a grid connector when the utility grid is not operating.

The present application relates to a battery charging method and charging system which can prevent degradation of a battery and enhance the lifetime characteristics thereof. In one aspect, the charging method includes charging a battery at a first C-rate higher than a reference C-rate, wherein the C-rate represents charge or discharge current/a rated capacity of the battery. The charging method also includes charging the battery at a second C-rate lower than the reference C-rate. The charging of the battery at the first C-rate includes at least one rest period for temporarily stopping the charging of the battery.

A method for depassivation of an energy storage device having an anode, a cathode and a core with an electrolyte, the method including: detecting that a first predetermined event related to a buildup of passivation has occurred with regard to the energy storage device; switching between a positive input voltage and a negative input voltage provided to the anode at a frequency sufficient to depassivate the anode; discontinuing the switching when a second predetermined event related to passivation has occurred.