Abstract: An approach is provided that determines that power from at least one battery cell in a multi-battery cell configuration is not required to power the device based on a power requirement of the device. The approach then regulates voltages from the battery cells so that first set of the battery cells is shunted (0 v) and a second set of the battery cells is regulated with the voltage being set to one or more voltage levels to satisfy the power requirement.

Abstract: A battery pack and a protection method of the battery pack are provided. The battery pack includes a battery including battery cells, a balancing unit for balancing voltages between the battery cells, a first switch on a high-current path of the battery, and a battery management unit for monitoring a voltage, a temperature, and a current of the battery, for applying a control signal for turning off the first switch, and for operating the balancing unit when the first switch is not turned off in response to the control signal.

Abstract: A microcontroller is operable to monitor power supply levels corresponding, respectively, to a first power supply (e.g., a main power supply) and a second power supply (e.g., a battery backup power supply). In one or more modes of operation, the same brownout detector in the microcontroller alternately monitors signals corresponding, respectively, to the first and second power supply levels.

Abstract: An electronic equipment chamber is disclosed. The electronic equipment chamber has an electronic equipment chamber board on which at least one electronic component among a current sensor, a relay, and a fuse is disposed, a controller located in a center of the electronic equipment chamber board, the controller electrically connected to the electronic component and configured to control the electronic component, and a plurality of busbars electrically connected to the electronic component and disposed along an outer edge of the electronic equipment chamber board, the plurality of busbars spaced apart from the controller.

Abstract: An electricity-storage system 110a is configured to be able to charge and discharge by connecting a plug to an electrical outlet 140a. Power discharged from the electricity-storage system 110a is monitored by a reverse-power monitoring device 100 and discharge from the electricity-storage system 110a is executed according to instruction from the reverse-power monitoring device 100, in order to avoid reverse power flow to an electrical grid 150.

Abstract: A battery voltage monitoring apparatus monitoring a voltage of an assembled battery, the assembled battery including a plurality of battery cells, comprising; a first voltage sensor module that monitors voltages of a plurality of battery cells arranged at a high voltage side; and a second voltage sensor module that monitors voltages of a plurality of battery cells arranged at a low voltage side, wherein the second voltage sensor module comprises a voltage sensor that is connected to a terminal and detects a voltage of a battery cell connected to the terminal, the terminal being supplied with a power source potential of the second voltage sensor module, the voltage sensor comprises a comparator including a first terminal and a second terminal, the first terminal being supplied with a voltage according to the voltage of the battery cell, the second terminal being supplied with a reference voltage.

Abstract: A back-up rechargeable battery supply system comprises communication linkages and a configuration of switches to allow battery back-up power to be provided by cells within a battery unit that are in a ready mode and to by-pass batteries that are in a non-ready mode, or maintenance mode. The unique configuration of switches and communication methods enables the back-up power to be provided very quickly to avoid disruptions in power to a load. Each battery cell has a charge and discharge switch and a power switch. Both the power switch and one of the charge or discharge switches must be closed to allow the battery cell to charge or discharge respectively. The by-pass switch may be controlled by the battery system control or by the cell controller and when closed, the cell may be bypassed from discharging or charging. The battery cells may be electrochemical cells such as metal air batteries.

Abstract: A battery power supply system and a battery power supply method for a main system are provided. The battery power supply system includes a power supply processor, an expansion slot module with plural slots, and plural battery units. The plural battery units are docked with the corresponding slots. Moreover, plural control switches are electrically connected between the corresponding slots and the power supply processor. A voltage value of one battery unit is defined as a fiducial voltage value. If the difference between the fiducial voltage value and the voltage value of at least one battery unit of the rest of the battery units is within a predetermined value, the control switch corresponding to the at least one battery unit is turned on. The battery unit with the fiducial voltage value and the at least one battery unit are connected with each other in parallel.

Abstract: An energy generation system includes an inverter power control system and a plurality of energy storage devices coupled to the inverter power control system. The inverter power control system includes an input configured to receive DC power; a DC/AC inverter stage configured to receive the DC power input; an anti-islanding relay coupled to the output of the DC/AC inverter stage; and a transition relay coupled to the anti-islanding relay, where the transition relay configured to route an output of the inverter power control system between one or more onsite back-up loads and an AC grid. Each energy storage device is configured to communicate with the inverter power control system.

Abstract: The present invention relates to a method for operating an energy storage unit having a plurality of battery cells (1) electrically connected to one another, each battery cell comprising an over-voltage protection device and a cell protection, wherein an adjacent battery cell voltage (14) on each battery cell (1) of the energy storage unit is monitored to determine whether said battery cell voltage is larger than a predetermined cell voltage minimum value (16), wherein the energy storage unit is switched off when the battery cell voltage (14) drops below the cell voltage minimum value (16). Thereby the battery cells (1) are monitored with respect to a triggering of the respective over-voltage protection devices, wherein the energy storage unit is further operated if a battery cell voltage (14) of a battery cell (1) of the energy storage unit exceeds the cell voltage minimum value (16) and the triggering of the over-voltage protection device of this battery cell (1) is thereby detected.

Abstract: A system for calculating total lifecycle costs for a building energy management system includes lifecycle costs for a grid-scale battery system. The system includes a battery lifecycle optimizer configured to provide an optimal battery configuration for a building and a building energy system controller. The building energy system controller receives optimum battery configuration information, information relating to the heat ventilation air conditioning system of the building, intrinsic thermodynamic properties of the building, energy tariff schedules and weather forecast data to forecast a monthly peak demand profile. A simulation is run using a battery model, system model along with tariff and weather information to produce an hourly building energy management plan for minimizing overall energy costs with consideration of system lifecycle costs.

Abstract: A battery system is described. The battery system includes a power controller having sensors monitoring the state of predetermined sections of battery modules within battery packs and sends signals to a switching network to connect a bi-directional DC/DC converter to a first predetermined group of battery modules of the plurality of predetermined groups of battery modules at a first instant of time responsive to a first measurement of a first predetermined section of battery modules, and a second predetermined section of battery modules of the plurality of predetermined groups of battery modules at a second instant of time responsive to a second measurement of a second predetermined group of battery modules.

Abstract: A cell balancing system includes sensing circuitry configured to sense a cell voltage of each of a plurality of cells of a battery. Cell balancing circuitry is configured to balance each of the plurality of cells in response to a respective cell balancing command for each of the plurality of cells. A comparison circuit configured to compare the sensed cell voltages for each of the plurality of cells to an adaptive threshold voltage. The comparison circuit generates a respective cell state for each of the plurality of cells to indicate a state of the respective cell voltage for each of the plurality of cells relative to the adaptive threshold voltage. A controller is configured to set the respective cell balancing command for each of the plurality of cells and to adjust the adaptive threshold voltage based on an evaluation of the cell states for the plurality of cells.

Abstract: One embodiment of the present disclosure describes a battery system including a battery module with a first and second cell group connected in series; and a cell control unit communicatively coupled to a plurality of sensors, in which the cell control unit includes a first analog-to-digital converter that outputs a first cell group voltage; a second analog-to-digital converter that outputs a second cell group voltage; outputs a measured battery module voltage; and logic circuitry that determines a calculated battery module voltage based at least in part on the first cell group voltage and the second cell group voltage; and determines whether a fault is expected to be present in the cell control unit, the battery module, or both based at least in part on the measured battery module voltage and the calculated battery module voltage.

Abstract: Methods, systems and battery modules are provided, which increase the cycling lifetime of fast charging lithium ion batteries. During the formation process, the charging currents are adjusted to optimize the cell formation, possibly according to the characteristics of the formation process itself, and discharge extents are partial and optimized as well, as is the overall structure of the formation process. During operation, voltage ranges are initially set to be narrow, and are broadened upon battery deterioration to maximize the overall lifetime. Current adjustments are applied in operation as well, with respect to the deteriorating capacity of the battery. Various formation and operation strategies are disclosed, as basis for specific optimizations.

Abstract: A battery assembly controller controls terminal voltages of a plurality of series-connected secondary batteries to be equal. The controller includes a discharge circuit selectively reducing the terminal voltages of the secondary batteries; and a monitoring circuit directly connected to positive and negative electrodes of the secondary batteries to monitor the terminal voltages of the secondary batteries.

Abstract: Methodologies and systems are described herein whereby performance parameters of a power converter may be tested. In one or more embodiments, a system for testing the performance parameters comprises a multi-channel monitoring device including a first channel for monitoring a switch voltage of a power converter and a second channel for concurrently monitoring an output voltage of the power converter. The system further comprises a set of one or more processors for generating, as a function of the switch voltage and the output voltage, and displaying an inductor current waveform approximating current through an inductor of the power converter. Additionally or alternatively, other waveforms such as output current waveforms and inductor voltage waveforms, may be generated during testing of the power converter. An arbitrary wave generator may inject different signals during testing of the power converter.

Abstract: The present disclosure provides an electric vehicle, a vehicle-mounted charger and a method for controlling the same. The method includes: obtaining a first total charging time and a second total charging time in a second manner, and a first total discharging time and a second total discharging time in the second manner; calculating a first total working time in the first manner and a second total working time in the second manner; obtaining a first predetermined charging time in the first manner, a second predetermined charging time in the second manner, a first predetermined discharging time in the first manner and a second predetermined discharging time in the second manner; selecting a manner according to the first and second total working time; and performing an alternate control according to the first and second predetermined charging time or according to the first and second predetermined discharging time.

Abstract: A battery system may include multiple battery cells having different chemistries. To achieve certain performance goals, voltage parameters for the battery system, such as cruising voltages and maximum voltages can be adjusted. These adjustments may, for example, direct charging currents to a lithium-ion battery to increase fuel economy or may direct charging currents away from a lithium-ion battery to increase its longevity. Methods for matching batteries having different chemistries based on their open circuit voltages are also discussed.

Abstract: The present disclosure relates to an apparatus for controlling charging of an environment-friendly vehicle. The apparatus includes a high-voltage battery SOC determining unit configured to determine a state of charge (SOC) of a high-voltage battery that is a main power source, an auxiliary battery SOC determining unit configured to determine an SOC of an auxiliary battery that assists power of the high-voltage battery, and an auxiliary battery charging control unit configured to, when receiving a request for an operation of an engine for controlling heating, perform a control such that the auxiliary battery is charged by using the high-voltage battery.

Abstract: A battery pack includes: a battery including at least one battery cell; a power line communicator connected to a current path to detect a first data signal; and a battery management system (BMS) to receive the first data signal from the power line communicator, and to control the battery according to the first data signal.

Abstract: Embodiments of the present disclosure provide an equalization circuit, a device to be charged and a charging control method. The equalization circuit includes: a first converting unit, configured to receive a direct voltage output by a first battery cell and to convert the direct voltage output by the first battery cell into a first alternating voltage; a first resonant unit, configured to receive the first alternating voltage and to convert the first alternating voltage into a second alternating voltage in a resonant manner; a first capacitive coupling unit and a second converting unit, in which the first capacitive coupling unit is configured to couple the second alternating voltage to the second converting unit in a capacitive coupling manner, and the second converting unit is configured to convert the second alternating voltage into a first charging voltage for charging a second battery cell.

Abstract: The disclosed charging system has multiple charging ports emanating from a central digital power transmitter to charge a plurality of battery packs. The system comprises a centralized bulk power converter to produce a first DC voltage and multiple additive power converters. One additive power converter is assigned to each charger port. The output of each charging port is transmitted in digital power format to a receiver local to each battery pack. The receiver converts the digital power to conventional analog DC power for charging the battery packs. The bulk converter provides the majority of the power needed to charge all the battery packs simultaneously, while the additive power converters adjust for the individual characteristics of each battery pack.

Abstract: A battery pack receives a charging current from a charger via a power line. The battery pack includes a battery management unit and a transmitting unit. The battery management unit is coupled to a plurality of battery cells and is operable for acquiring data associated with the battery pack. The transmitting unit is coupled to the battery management unit and is operable for transmitting the data to the charger via a power line.

Abstract: Disclosed is a battery management method and corresponding apparatus to manage a battery including determining state information of a target battery, among batteries, based on quantity data of the target battery. The method and apparatus also includes determining state information of a battery, different from the target battery, among the batteries, based on the state information of the target battery and difference information between electrical quantity data of the different battery and the electrical quantity data of the target battery.

Abstract: An electric storage apparatus according to one aspect of an embodiment includes a plurality of storage batteries, a virtual processing unit, and a connection controlling unit. The virtual processing unit virtually and sequentially connects in parallel two or more storage batteries, of the plurality of storage batteries, having a potential difference or potential differences within a predetermined range so as to equalize electric potentials of the two or more storage batteries. The connection controlling unit connects in parallel the two or more storage batteries in a connection order for maximizing the number of the two or more storage batteries to be connected in parallel when the virtual processing unit sequentially connects in parallel the two or more storage batteries in an order from highest electric potential to lowest one and in an order from lowest electric potential to highest one.

Abstract: An electric storage apparatus according to one aspect of an embodiment includes a battery unit, a determination unit, a virtual processing unit, and a connection controlling unit. The battery unit includes storage batteries to be connected in parallel. The determination unit determines, when the battery unit is started up, a startup type indicating a discharge start or a charge start. The virtual processing unit generates connection orders. Each of the connection orders is obtained by virtually and sequentially connecting in parallel storage batteries, of the storage batteries, having potential differences within a predetermined range so as to equalize electric potentials of the storage batteries. The connection controlling unit selects, among from the connection orders, a connection order in which the equalized electric potential is an electric potential according to the startup type determined by the determination unit, so as to connect in parallel the storage batteries.

Abstract: Various embodiments of a technique to estimate and monitor a self-discharge rate for use as a measure of battery health are described herein. In some embodiments, the technique includes a system including a processor and a memory coupled with the processor. The memory is configured to provide the processor with instructions that when executed cause the processor to receive a plurality of snapshots obtained by monitoring a battery system in a quiescent state at a plurality of times. Each snapshot includes a plurality of cell state values at one of the plurality of times. The memory is further configured to provide the processor with instructions that when executed cause the processor to estimate a self-discharge indicator using at least one snapshot in the plurality of snapshots, compare the self-discharge indicator to a threshold, and recommend a remedy for the battery system in response to the self-discharge indicator exceeding the threshold.

Abstract: A capacity restoration system restores a capacity of a battery pack including lithium ion secondary batteries and mounted on a vehicle. The capacity restoration system includes a capacity restoration device, a communication device, and a server. The capacity restoration device is configured to perform a restoration process to restore a capacity of the battery pack by maintaining a SOC of the battery pack to be equal to or less than a reference value. The communication device is configured to acquire restoration data. The restoration data includes: the reference value for the SOC, the reference value being used for the restoration process; and a capacity restoration ratio attained by the restoration process. The server is configured to use the restoration data to calculate the reference value used for the restoration process for a target vehicle.

Abstract: Disclosed is an overcharge detection method for detecting an overcharging of an accumulator of a battery including a set of parallel branches each including accumulators disposed in series, wherein the method includes steps of: (i) collecting the measurements of the currents flowing in the branches of the battery; (ii) identifying at least one variation in current in one branch with respect to at least one other branch as a function of the measurements of current collected; (iii) determining a level of state of charge of the branch; and (iv) detecting an overcharging of an accumulator in the branch as a function of at least the variation in current identified and of the level of state of charge determined.

Abstract: A power device, system and method. The device may include a housing defining a first support operable to support a first battery pack, and a second support operable to support a second battery pack; a circuit selectively electrically connecting the first battery pack and the second battery pack in series, the circuit including an output terminal to provide an output voltage to a powered device, a first bypass portion operable to selectively electrically disconnect the first battery pack from the circuit, and a second bypass portion operable to selectively electrically disconnect the second battery pack from the circuit; and a boost converter electrically connected to the circuit and operable to boost a voltage at the output terminal.

Abstract: A method of determining battery power capability may include: determining a circuit model for a battery, including a first resistance (r1) in series with a second resistance (r2) and a capacitance (C) in parallel; setting upper and lower limits for r1, r2 and C based on a battery temperature a battery state of charge or both; applying an EKF to determine r1, r2 and C within the set upper and lower limits; and outputting the battery power capability based on r1, r2 and C. The upper and lower limits may be adjusted based on the age of the battery.

Abstract: Provided is a power source device having a high efficiency. A power source device 1 includes an insulated AC-DC converter 2 which receives a voltage of an AC power source 10 and outputs a link voltage Vlink, a bidirectional DC-DC converter 3 which receives the link voltage Vlink to charge a main battery 5, an insulated DC-DC converter 4 which receives the link voltage Vlink to supply power to a load 7, an operation mode in which the power is supplied from the AC power source 10 to the main battery 5, and an operation mode in which the power is supplied from the main battery 5 to the load 7.

Abstract: The present invention relates to a charger device (100) comprising: a sensor (10) which is configured to measure a differential current (DELTA_I) as a difference between a first current (I_POS) through a first battery portion (210) of a battery (200) and a second current (I_NEG) through a second battery portion (220) of the battery (200) and which is configured to provide a current difference signal (?I_meas) based on the measured differential current (DELTA_I); a compensator (20) which is configured to calculate a first current setpoint (I_SP_POS) used for the first battery portion (210) and a second current setpoint (I_SP_NEG) used for the second battery portion (220) based on the provided current difference signal (DELTA_I) and a battery current setpoint (I_SP); and a controller (30) which is configured to control charging and/or discharging of the first battery portion (210) based on the first current setpoint (I_SP_POS) and of the second battery portion (220) based on the second current setpoint (I_SP_NE

Abstract: Embodiments of a welding power supply include an engine adapted to drive a generator to produce a first power and a energy storage device adapted to discharge energy to produce a second power. The welding power supply also includes control circuitry adapted to detect a commanded output. The control circuitry is adapted to meet the commanded output by controlling access to power from the energy storage device to produce the second power when the commanded output is below a first predetermined load level. The control circuitry is further adapted to meet the commanded output by controlling access to power from the engine and the energy storage device to produce the first power and the second power when the commanded output is above a second predetermined load level.

Abstract: A handheld power tool battery pack includes a plurality of battery cells, which have a positive cell pole at one end and a negative cell pole at an opposite end, connecting conductors which are provided for electrically connecting the battery cells, a connecting side, and a side opposite the connecting side. The battery cells have one integrated cell connector which is provided for the purpose of making one of the cell poles of the battery cell electrically connectably available at the end of the other cell pole of the battery cell, and that the connecting conductors for electrically connecting the battery cells are situated only on the connecting side.

Abstract: An electric power retention distribution cell apparatus and method of operation of the cell includes a rechargeable battery assembly, a bi-directional inverter and a switch control operatively connectable to an electric utility grid, an outside power charging supply and at least one end user wherein the cell is selectively switched between the electric utility grid and the battery assembly to supply electric power to the one or more end users. The cell is connected to the power charging supply for charging the battery assembly, and for dividing the battery assembly into groups of batteries for storage at a lower terminal output voltages of each group than the battery assembly output voltage when in use as the primary power supply. Electric power supply networks are also described for a utility hub network formed using two or more cells, and for a regional utility hub network formed using multiple utility hubs.

Abstract: A distributed charge controller that matches a charging and power profile of each individual battery cell within a bank of batteries with one or more strings of photovoltaic (PV) cells in order to maintain battery health and performance. The charge controller further optimizes the performance of a solar module by allowing active unshaded strings of cells to operate independently of other strings within the module that may be shaded. Strings of PV cells are selectively matched to one or more battery cells as required.

Abstract: A magnetic assembly structure comprises a first main body and a second main body. The first main body comprises at least one first buckle structure. The second main body comprises a tail terminal portion, at least one magnetic attraction unit, at least one second buckle structure and at least one releasing structure. The tail terminal portion, the second buckle structure and the releasing structure form a loop, the first buckle structure is capable of being engaged to the second buckle structure, and the first buckle structure moves in respect to the second buckle structure and the releasing structure. The first buckle structure and the magnetic attraction unit attract each other due to a magnetic attraction effect. By the loop design, merely one directional force is needed to achieve the objective of facilitating assembling and detaching, thus having results of reducing assembling cost and time consumption.

Abstract: Provided is a battery balancing apparatus and method including determining state information of a battery unit based on battery quantity data of the battery unit, determining a balancing parameter of the battery unit based on a range comprising the state information, and controlling a balancing unit based on the balancing parameter.

Abstract: A power electronics system for charging at least one electrically operated vehicle, wherein the power electronics system has at least two modules each having at least one terminal pair with DC output, at least one rectifier, at least one AC input, at least one DC link and a number of switching elements the switching elements are arranged at and/or between the DC outputs of the at least two modules in such a way that, between the at least two modules, at least one series and one parallel circuit configuration can be selectively dynamically set by suitable switching states of the switching elements.

Abstract: The present invention relates to a battery cell balancing system and method using LC resonance. The present invention comprises: a drive unit including one or more battery cells connected in series, a resonance module for performing a resonant operation, and a switch unit provided so as to allow electric charges stored in the resonance module to be transferred to each of the one or more battery cells; and a control unit for measuring a resonance period of the resonance module according to a voltage state of each of the one or more battery cells, and transferring the electric charges charged in the resonance module to each of the one or more battery cells by controlling an on/off operation of the switch unit according to the measured resonance period.

Abstract: A hybrid power plant is characterized by a substantially constant load on generators regardless of momentary swings in power load. Short changes in power load are accommodated by DC components such as capacitors, batteries, resistors, or a combination thereof. Resistors are used to consume power when loads in the power plant are generating excess power. Capacitors are used to store and deliver power when the loads in the power plant demand additional power. Reducing rapid changes in power load as seen by the generators allows the generators to operate at higher efficiencies and with reduced emissions. Additionally, power plants employing combinations of generators, loads, and energy storage devices have increased dynamic performance.

Abstract: A battery characteristics learning apparatus is provided for calculating learning values of circuit constants of an equivalent circuit of a rechargeable battery. The apparatus includes: (1) means for acquiring values of terminal voltage of the battery sensed by voltage-sensing means and values of current of the battery sensed by current-sensing means and storing the acquired values in time series; (2) means for determining, based on the acquired values of the current, whether there has occurred a predetermined change in the current; and (3) means for calculating, when it is determined that the predetermined change has occurred, the learning values of the circuit constants based on those values of the terminal voltage and the current which are acquired at sampling time points or during sampling periods, each of the sampling time points and the sampling periods being set according to a corresponding one of time constants defined by the circuit constants.

Abstract: A first voltage sensor measures a primary voltage between a first terminal of a tested device and electrical ground when a first switch and a second switch are in various on states or off states. In a test state either the first switch or the second switch is in an on state and in reference state both the first switch and the second switch are in on states. An observed leakage resistance is estimated based on the measured primary and secondary voltages of the test state. A reference leakage resistance is based on the measured primary and secondary voltages of the reference state. A test circuit has failed if the observed leakage resistance differs from the reference leakage resistance by more than a threshold amount.

Abstract: A power storage apparatus includes a plurality of power storage modules connected in series and a control apparatus that controls each power storage module. The power storage module includes a battery section, a controller, a communication unit, a first insulator that insulates the controller from the communication unit, and a second insulator having a withstand voltage higher than a withstand voltage of the first insulator. The second insulator is provided between the communication unit of each power storage module and the control apparatus.

Abstract: A battery-affixing frame member includes a body plate section and duct-forming members. The duct-forming members are affixed to one surface side of the body plate section and are combined with the body plate section to form gas discharge ducts. The gas discharge ducts are used to discharge gas discharged from the inside of battery modules. The battery-affixing frame member is used to form a battery-affixing member for integrally affixing the battery modules together, the battery modules being arranged on the other surface side of the body plate section.

Abstract: A battery management system (BMS) described herein determines the internal resistance for a cell that may have an internal short circuit. In one aspect, the BMS monitors the voltage across each of a plurality cells that are coupled in series. If the voltage across one of the cells differs from the voltages across the other cells, the BMS can flag the cell as potentially having an internal short circuit. Once flagged, the BMS can use a simulator that stores a model cell that has similar characteristics as the cells monitored by the BMS to determine the internal resistance of the flagged cell. In one aspect, the simulator changes the value of a surrogate resistor that is parallel with the model cell until the voltage across the model cell matches the voltage of the flagged cell. The value of the surrogate resistor indicates the internal resistance of the flagged cell.

Abstract: A computer-implemented method, system, and computer program product are provided for demand charge management. The method includes receiving an active power demand for a facility, a current load demand charge threshold (DCT) profile for the facility, and a plurality of previously observed load DCT profiles. The method also includes generating a data set of DCT values based on the current load DCT profile for the facility and the plurality of previously observed load DCT profiles. The method additionally includes forecasting a next month DCT value for the facility using the data set of DCT values. The method further includes preventing actual power used from a utility from exceeding the next month DCT value by discharging a battery storage system into a behind the meter power infrastructure for the facility.

Abstract: In order to provide a charge/discharge control circuit capable of controlling a charge/discharge current of secondary batteries that are connected in parallel, the charge/discharge control circuit includes: a first power supply terminal and a second power supply terminal to which a respective first electrode of each of secondary batteries which are connected in parallel is connected; a third power supply terminal to which second electrodes of the secondary batteries are connected; a connection circuit configured to connect the first power supply terminal and the second power supply terminal to generate an electric potential for an output; and a controller configured to operate on a potential difference between the electric potential supplied from the connection circuit and an electric potential supplied from the third power supply terminal, and to control charging/discharging of the first secondary battery and the second secondary battery.