A battery system, control device, and control method are provided that can improve the cycle service life. One aspect of the present invention is a battery system comprising: a plurality of battery units including at least one battery cell that has a negative electrode that is free of a negative electrode active material; a plurality of switches that can switch between a first state in which a battery unit is connected to a charging pathway or a discharge pathway, and a second state in which a battery unit is not connected to the charging pathway or the discharge pathway; a charge control unit; and a discharge control unit, wherein the charge control unit includes a first switch control unit that simultaneously sets “a” (where “a” is an integer equal to or greater than 2) selected switches to the first state and sets the remaining switches except the “a” switches to the second state, and the discharge control unit includes a second switch control unit that simultaneously sets “b” (where “b” is an integer less than “a”) selected switches to the first state and sets the remaining switches except the “b” switches to the second state.

A temperature raising system includes an alternating current (AC) generation circuit connected to a power storage battery including one or more power storages and configured to generate an AC current, and a conductive member of a metallic conductor connected between a terminal portion of the power storage and the AC generation circuit or between two or more power storages. The conductive member includes a first path and a second path along which heat is generated by allowing the AC current to flow. The first path has a larger inductance component than the second path.

An open cell detection system includes a battery management system. The battery management system includes a control unit that transmits an open cell detection signal, to enable a balance unit for a first time period and to disable it for a second time period, and to enable an under-voltage comparison unit and an over-voltage comparison unit for a third time period. The under-voltage comparison unit compares a voltage with a first open cell threshold and outputs a first comparison result in the third time period. The over-voltage comparison unit compares a voltage with a second open cell threshold and outputs a second comparison result in the third time period. A judging unit determines whether a connection between a first battery unit and the battery management system is inoperative based on the first and second comparison results.

A battery management apparatus includes: an inverter connected to a battery cell and configured to convert a DC current output from the battery cell into an AC current according to an operation state of a plurality of switches provided therein; a measuring unit connected to a diagnosis line at which the AC current converted by the inverter is output, the measuring unit being configured to measure a voltage of the diagnosis line and output the measurement result; and a control unit having a plurality of capacitors connected to the diagnosis line and configured to control the operation state of the plurality of switches, receive the measurement result output from the measuring unit and diagnose a state of the plurality of capacitors based on the received measurement result.

An energy storage system used in a flight vehicle includes: a plurality of energy storage apparatuses; and a power transfer circuit that is connected to the plurality of energy storage apparatuses and transfer electric power between the plurality of energy storage apparatuses.

A power storage device or the like with low power consumption is provided. Alternatively, a power storage device or the like with high integration is provided. A first battery cell includes a first electrode over a first substrate, a positive electrode active material layer over the first electrode, an electrolyte layer over the positive electrode active material layer, a negative electrode active material layer over the electrolyte layer, and a second electrode over the negative electrode active material layer. The comparison circuit includes a first input terminal, a second input terminal, an output terminal, and a first transistor. The first transistor includes an oxide semiconductor over the first substrate, a first insulator over the oxide semiconductor, and a gate electrode over the first insulator. The first electrode is electrically connected to the gate of the first transistor and the first input terminal. The comparison circuit has a function of outputting a first signal in response to a result of comparison between a potential of the first electrode and a desired reference potential from the output terminal to the control circuit. The control circuit has a function of controlling charging of the first battery cell in accordance with the first signal.

A battery pack includes a battery cell, a main relay provided on a charging and discharging path of the battery cell, a precharge relay, a precharge resistor, the precharge relay and the precharge resistor being connected in parallel to the main relay on the charging and discharging path, a connector connected to a load including a capacitor; a communication part receiving a capacitance of the capacitor from the load through the connector, when the load is connected to the connector, and a controller obtaining the capacitance from the communication part, calculating a duty ratio corresponding to the capacitance, and precharging the capacitor by controlling an operation state of the precharge relay according to the calculated duty ratio.

A bipolar capacitor assisted battery includes a bipolar capacitor including a first capacitor, and a second capacitor. The second capacitor is connected in series with the first capacitor. A lithium ion battery is connected in parallel to the bipolar capacitor.

The invention relates to a battery pack type device including a first terminal (101), a second terminal (102) and a plurality of energy storage elements between these terminals, each element including:

a) at least one switch for connecting it with, or to disconnect it from, one or more other element(s);
b) at least one conductor (15, 17) for conducting a current, parallel to the element, when the latter is not connected with one or more other element(s);
c) at least one switch (20) for establishing a short-circuit between the terminals of the battery when the latter is disconnected or supplies a zero voltage;
d) a control circuit (30), specifically adapted to: select at least one first energy storage element and at least one second energy storage element, at least one of these elements being to be heated up, to make a current circulate at least from the first element to the second element when the terminals (101, 102) are short-circuited; stop the current when a setpoint temperature for one or more element(s) of the pack is reached.

A power supply unit includes: a power supply configured to discharge power to a load for generating an aerosol from an aerosol generation source; a charger configured to convert inputted power into charging power; a temperature measuring unit configured to measure a temperature of the power supply; and a charging controller configured to perform a first control for stopping the charger from supplying the charging power to the power supply and a second control for causing the charger to supply the charging power to the power supply, the charging controller setting a duty ratio to a value greater than 0 and smaller than 100 in a case where the temperature of the power supply is within a predetermined range, and the duty ratio being obtained by dividing a time during which the charging controller performs the first control by a unit time.