A method and system for AC battery operation. In one embodiment, the method comprises determining, at a battery management unit (BMU) coupled to an AC battery comprising a power converter and a battery that is rechargeable, a bias control voltage that indicates a state of a charge process of the AC battery; and coupling, by a bias control module of the BMU, the bias control voltage to the power converting for communicating the state of the charge process to and from the BMU and the power converter.

An electrical combination. The combination comprises a hand held power tool, a battery pack and a controller. The battery pack includes a battery pack housing connectable to and supportable by the hand held power tool, a plurality of battery cells supported by the battery pack housing, each of the plurality of battery cells having a lithium-based chemistry, being individually tapped and having an individual state of charge. A communication path is provided by a battery pack sense terminal and a power tool sense terminal. The controller is operable to monitor a state of charge of a number of battery cells less than the plurality of battery cells and to generate a signal based on the monitored state of charge of the number of battery cells less than the plurality of battery cells, the signal being operable to control the operation of the hand held power tool.

The invention relates to a control for an electrical energy supply unit, comprising a first filling level input, to which a first filling level of a first energy store of the electrical energy supply unit can be transmitted. In addition, the control comprises a further filling level input, to which a further filling level of an optional further energy store of a further electrical energy supply unit can be transmitted. Furthermore, the control comprises a nominal alternating voltage determiner which is designed to determine a nominal alternating voltage while taking into account the first filling level and/or the further filling level. In addition, the control comprises a nominal alternating voltage output, from which the nominal alternating voltage can be transmitted to an alternating voltage generator of the electrical energy supply unit. An electrical energy supply unit comprises a control according to the invention, a first energy store and an alternating voltage generator having a first and a second terminal. The first terminal of the alternating voltage generator is connected to the first energy store in an electrically conductive manner. The alternating voltage generator is designed to generate at the second terminal an alternating voltage that corresponds to a nominal alternating voltage. An electrical energy supply system comprises an electrical energy supply unit according to the invention and at least one additional electrical energy supply unit according to the invention, which are connected to one another in an electrically conductive manner.

A battery pack, power tool, and power tool combination. The battery pack includes one or more battery cells, a first terminal electrically connected to the one or more battery cells, a high current power supply terminal, a power switch electrically connected between the one or more battery cells and the high current power supply terminal, and a low current power supply terminal electrically connected to the one or more battery cells. The first terminal and low current power supply terminal are operable to provide a substantially continuous low current to the power tool during a normal operating state of the battery pack. The battery pack also includes a controller operable to control the power switch to provide high current power through the high current power supply terminal in response to a call for power from the power tool.

The invention relates to a circuit for an electrical energy storage system (100) with two energy storage units (R1, R2) respectively comprising a first and a second pole connection (P1, P4, P3, P2), said circuit comprising: at least one first and one second input (E1, E2), at least one first and one second output (A1, A2), a first switching element (S1) between the first pole connection (P1) of the first energy storage unit (R1) and the first output (A1), and a second switching element (S2) between the second pole connection (P2) of the second energy storage unit (R2) and the second output (A2), a third switching element (S3) being arranged between the second pole connection (P3) of the first energy storage unit (R1) and the first pole connection (P4) of the second energy storage unit (R2), a fourth switching element (S4) being arranged between the second pole connection (P3) of the first energy storage unit (R1) and the second pole connection (P2) of the second energy storage unit (R2), and a fifth switching element (S5) being arranged between the first pole connection (P1) of the first energy storage unit (R1) and the first pole connection (P4) of the second energy storage unit (R2), the energy storage units (R1, R2) being connected in parallel or in series according to the switch position of the third, fourth and fifth switching elements (S3, S4, S5).

A protective device connected between an external terminal provided in an energy storage apparatus and a power cable extending from a vehicle, the protective device includes a current interruption device that interrupts electric conduction between the vehicle and the energy storage apparatus in response to a command of a CPU in a battery management device provided in the energy storage apparatus.

Provided is an ESS charging/discharging schedule management device, and in particular, to an ESS charging/discharging schedule management device which maintains the charging/discharging efficiency of an energy storage device and minimizes an equalized discharge amount during a maximum load time period, thereby preventing a decrease in a customer baseline load which is a baseline for power demand response bidding.

A battery control device that controls a battery assembly includes a first determining unit that determines whether a voltage difference between minimum and maximum values of OCVs of battery cells constituting the battery assembly and having an SOC-OCV characteristic curve including a flat region is equal to or larger than a predetermined voltage value, a second determining unit that determines whether the OCV of each battery cell is lower than a lower-limit voltage of the flat region, or is equal to or higher than the lower-limit voltage and lower than an upper-limit voltage, or is higher than the upper-limit voltage, a controller that executes control selected from SOC raising control, SOC lowering control, and SOC keeping control of the battery cells, based on determination results of the first and second determining units, and a processor that homogenizes the SOCs of the battery cells controlled by the controller.

A battery management unit for a battery system with a conductor or a busbar, the battery management unit including a printed circuit board, and a fluxgate current sensor including a magnetic core having a through-hole, at least one excitation winding, at least one compensation winding, and a sensor circuit configured to measure a magnetization of the at least one excitation winding, to generate a driving signal for driving the at least one compensation winding, to generate a current flowing through the at least one compensation winding according to the driving signal, and to generate an output signal corresponding to a magnitude of an electric current flowing through the through-hole of the magnetic core, wherein the magnetic core, the at least one excitation winding, the at least one compensation winding, and the sensor circuit are each integrated into the printed circuit board.

A battery equalization method includes: obtaining a voltage value of a to-be-equalized cell in a battery pack; obtaining a reference voltage value required for equalization; determining a target equalization duration of the to-be-equalized cell according to a voltage value of the to-be-equalized cell, the reference voltage value, and a preset equalization duty cycle, where the equalization duty cycle is a ratio of an equalization period in a unit cycle to the unit cycle, and the unit cycle includes the equalization period and a sampling period; and controlling equalization of the to-be-equalized cell in the equalization period in the unit cycle according to the target equalization duration. According to this method, sampling is separated from equalization in a unit cycle, thereby ensuring accuracy of collected battery information, making the calculated equalization duration relatively accurate, and improving equalization effects of the battery pack.