Management device, power storage device, power storage system, and electrical apparatus

Abstract

As a result of using each battery module in different environments, there is a difference in degradation states among a plurality of battery modules, and it is desirable to reduce man-hours and costs for managing the battery modules. A management device is provided with: an equalization unit that equalizes the voltages of a plurality of power storage cells; and a power transmission / reception unit that does not cut off or switch (a) the electrical connection between the plurality of power storage units and (b-1) a load that uses the power of the plurality of power storage units or (b-2) a charging device that charges the plurality of power storage units, and (i) transmits the power of the plurality of power storage units to an external device that is different from the load and the charging device. Or (ii) receives power supplied to the plurality of power storage units from an external device.

Description

[0001] This invention patent application is a divisional application of the invention patent application with application number 201711297951.X, title “Management device, power storage device, power storage system and electrical equipment” and application date December 8, 2017. Technical Field

[0002] The present invention relates to a management device, a power storage device, a power storage system and an electrical device. Background Art

[0003] A battery module having an assembled battery including a plurality of storage cells connected in series and an equalizing circuit for equalizing voltages between the plurality of storage cells in the assembled battery is known (see Patent Documents 1 to 3 and Non-Patent Document 1). In recent years, battery packs including a plurality of battery modules connected in series have begun to be used.

[0004] [Background Technology Literature]

[0005] [Patent Document]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 11-176483

[0007] [Patent Document 2] Japanese Patent Application Publication No. 2011-087377

[0008] [Patent Document 3] Japanese Patent Application Publication No. 2013-243806

[0009] [Non-patent literature]

[0010] [Non-Patent Document 1] Linear Technology Corporation, “LTC3300-1 - High Efficiency Bidirectional Multi-Cell Battery Balancer”, [Online], [retrieved on July 13, 2017], Internet, <URL: http: / / www.linear-tech.c0.jp / product / LTC3300-1> Summary of the invention

[0011] [Problems to be solved by the invention]

[0012] There are cases where each battery module of a battery pack is arranged at a different position of an electrical device, or a battery pack is constructed using battery modules having different numbers of storage cells or rated voltages. Using each battery module in different environments may result in differences in degradation states between multiple battery modules. In addition, it is desirable to reduce the man-hours and costs of managing battery modules.

[0013] [Methods of solving the problem]

[0014] In a first aspect of the present invention, a management device is provided. The management device, for example, manages the charging and discharging of a plurality of storage cells connected in series. The management device, for example, has an equalization unit that equalizes the voltages of the plurality of storage cells. The management device, for example, has a power transmission and reception unit that does not cut off or switch the electrical connection between (a) the plurality of storage cells and (b-1) a load that utilizes the power of the plurality of storage cells or (b-2) a charging device that charges the plurality of storage cells, but (i) transmits the power of the plurality of storage cells to an external device different from the load and the charging device, or (ii) receives the power supplied to the plurality of storage cells from the external device.

[0015] In the management device, the external equipment may include one or more storage units that are arranged between (a) multiple storage units and (b-1) loads or between (b-2) charging devices and connected in series with multiple storage units. In the management device, the power transmission and reception unit may have a voltage adjustment unit that adjusts the voltage of the power transmitted or received to an arbitrary value. In the management device, the power transmission and reception unit may start power transmission or power reception according to a received signal for starting power transmission or power reception. In the management device, the power transmission and reception unit may stop power transmission or power reception according to a received signal for stopping power transmission or power reception. In the management device, the power transmission and reception unit may include an insulated bidirectional DC-DC (Direct Current to Direct Current) converter.

[0016] The management device may include a storage unit that stores first identification information and second identification information assigned to each of the plurality of storage units. The management device may include an identification information conversion unit that refers to the information stored in the storage unit, converts the first identification information included in the signal received from the outside into the second identification information, and converts the second identification information included in the signal sent to the outside into the first identification information. In the management device, the second identification information assigned to each of the plurality of storage units may be different from each other. In the management device, the first identification information assigned to each of the plurality of storage units may be respectively (i) different from all the second identification information. In the management device, the first identification information assigned to each of the plurality of storage units may be respectively (ii) consistent with all the second identification information.

[0017] According to a second aspect of the present invention, there is provided an electric storage device. The electric storage device includes, for example, a plurality of electric storage cells. The electric storage device includes, for example, the management device according to the first embodiment.

[0018] In a third aspect of the present invention, a power storage system is provided. The power storage system, for example, has a plurality of power storage devices according to the second embodiment. The power storage system, for example, has a power line electrically connected to a power transmission and reception unit of each power storage device so that power can be transmitted between any power storage devices. The power storage system, for example, has a control unit that controls the power transmission and reception unit of at least one power storage device. In the power storage system, for example, a plurality of power storage units of each power storage device are connected in series.

[0019] In the power storage system, the rated voltage of a first power storage device constituting a plurality of power storage devices and the rated voltage of a second power storage device may be different from each other. In the power storage system, the number of a plurality of power storage cells included in the first power storage device constituting a plurality of power storage devices and the number of a plurality of power storage cells included in the second power storage device constituting a plurality of power storage devices may be different from each other. In the power storage system, a power transmission and reception unit of at least one of the first power storage device and the second power storage device may include a bidirectional DC-DC converter.

[0020] In the power storage system, the first power storage device may be the power storage device disposed closest to the negative electrode among the plurality of power storage devices. In the power storage system, the positive terminals and negative terminals of the plurality of power storage cells of the first power storage device are physically connected to the power line and may be always electrically connected to the power line.

[0021] In the power storage system, the control unit may include a determination unit that determines, based on the voltage or charge / discharge state (SOC) of each of the plurality of power storage units included in the plurality of power storage devices, (i) a power storage device that transmits power to the power line and (ii) a power storage device that receives power from the power line. In the power storage system, the control unit may include a command generation unit that generates at least one of (i) a command for causing a power transmission / reception unit of the power storage device that transmits power to the power line to start a power transmission operation and (ii) a command for causing a power transmission / reception unit of the power storage device that receives power from the power line to start a power reception operation.

[0022] In the power storage system, the determination unit may determine at least one of (i) a power storage device that stops power transmission and (ii) a power storage device that stops power reception based on the voltage or charge / discharge state of each of the plurality of power storage units included in each of the plurality of power storage devices. In the power storage system, the command generation unit may generate at least one of (i) a command for causing a power transmission / reception unit of the power storage device that stops power transmission to stop power transmission and (ii) a command for causing a power transmission / reception unit of the power storage device that stops power reception to stop power reception.

[0023] In a fourth aspect of the present invention, a power storage system is provided. The power storage system, for example, includes a plurality of power storage devices. The power storage system, for example, includes a control unit that controls each of the plurality of power storage devices. In the power storage system, the plurality of power storage devices, for example, each includes a plurality of power storage cells connected in series. In the power storage system, the plurality of power storage devices, for example, each includes an equalization unit that equalizes the voltages of the plurality of power storage cells. In the power storage system, the plurality of power storage devices, for example, each includes a storage unit that stores first identification information and second identification information assigned to each of the plurality of power storage cells. In the power storage system, the plurality of power storage devices, for example, each includes an identification information conversion unit that converts the first identification information included in a signal received from the control unit into the second identification information, and converts the second identification information included in a signal sent to the control unit into the first identification information, with reference to the information stored in the storage unit. In the power storage system, for example, the plurality of power storage cells of each power storage device are connected in series. In the power storage system, for example, the first identification information assigned to each of the plurality of power storage cells is different from each other. In the power storage system, for example, the first identification information assigned to each of the plurality of power storage cells is (i) different from all the second identification information or (ii) identical to all the second identification information.

[0024] In the power storage system, in at least one of the plurality of power storage devices, the equalization unit, the storage unit, and the identification information conversion unit may be physically arranged in different housings. In the power storage system, in at least one of the plurality of power storage devices, the equalization unit, the storage unit, and the identification information conversion unit may be physically arranged on different substrates. In the power storage system, at least two of the plurality of power storage devices may be connected in parallel. In the power storage system, at least two of the plurality of power storage devices may be connected in series.

[0025] According to a fifth aspect of the present invention, there is provided an electric device. The electric device includes, for example, the power storage system according to the third aspect or the fourth aspect. The electric device includes, for example, a load that utilizes electric power of the power storage system.

[0026] In addition, the summary of the invention does not list all possible features of the present invention. In addition, sub-combinations of these feature groups may also constitute inventions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 An example of the system configuration of the battery pack 100 is schematically shown.

[0028] Figure 2 An example of the internal structure of the battery module 112 is schematically shown.

[0029] Figure 3An example of the internal structure of the battery module 114 is schematically shown.

[0030] Figure 4 An example of the internal structure of the balance correction unit 220 is schematically shown.

[0031] Figure 5 An example of the internal structure of the balance correction circuit 432 is schematically shown.

[0032] Figure 6 An example of the internal structure of the DC-DC converter 330 is schematically shown.

[0033] Figure 7 An example of the internal configuration of the system control unit 130 is schematically shown.

[0034] Figure 8 An example of the system configuration of the electric vehicle 800 is schematically shown.

[0035] Fig. 9 An example of the system configuration of the battery pack 900 is schematically shown.

[0036] [Explanation of Reference Numerals]

[0037] 32 signals

[0038] 52 drive signal

[0039] 54 drive signal

[0040] 56 Signal

[0041] 58 action control signal

[0042] 100 Battery Pack

[0043] 102 terminal

[0044] 104 terminal

[0045] 112 battery module

[0046] 114 battery module

[0047] 116 battery module

[0048] 122 Channel Selector

[0049] 124 Channel Selector

[0050] 126 Channel Selector

[0051] 130 System Control Department

[0052] 140 Power transmission bus

[0053] 142 Low potential bus

[0054] 144 High potential bus

[0055] 202 terminal

[0056] 204 terminal

[0057] 210 Battery Pack

[0058] 212 Voltage Management Department

[0059] 220 Balance Correction Department

[0060] 230 Protection Department

[0061] 242 terminal

[0062] 244 terminal

[0063] 312 Voltage Management Department

[0064] 330DC-DC Converter

[0065] 412 Storage Unit

[0066] 414 Storage Unit

[0067] 416 Storage Unit

[0068] 418 Storage Unit

[0069] 432 Balance Correction Circuit

[0070] 434 Balance Correction Circuit

[0071] 436 Balance Correction Circuit

[0072] 443 Connection Point

[0073] 445 Connection Point

[0074] 447 Connection Points

[0075] 447 Connection Points

[0076] 545 Connection Points

[0077] 550 Inductor

[0078] 552 Switching elements

[0079] 554 Switching elements

[0080] 562 Diode

[0081] 564 diode

[0082] 570 Equalization Control Department

[0083] 580 Voltage Monitoring Department

[0084] 582 Voltage detection unit

[0085] 584 Voltage detection unit

[0086] 586 Differential detection unit

[0087] 590 Module Control Unit

[0088] 610 Transformer

[0089] 622 Switching elements

[0090] 624 Switching elements

[0091] 632 diode

[0092] 634 Diode

[0093] 642 Discharge Control Unit

[0094] 644 Charging Control Unit

[0095] 652 Current detection unit

[0096] 654 Current detection unit

[0097] 662 Capacitor

[0098] 664 Capacitor

[0099] 710 Module Management Department

[0100] 720 Module Selection Department

[0101] 730 Signal Generation Department

[0102] 800 Electric Vehicles

[0103] 810 Electric Motor

[0104] 900 Battery Pack

[0105] 920 Battery Module

[0106] 932 Channel Selector

[0107] 934 Channel Selector

[0108] 940 Battery Module

[0109] 942 Current detection unit

[0110] 944 Current detection unit

[0111] 952 Switching Department

[0112] 954 Switching Department DETAILED DESCRIPTION

[0113] The present invention is described below by way of embodiments of the invention, but the following embodiments do not limit the invention involved in the claims. The combination of features described in the embodiments may not all be necessary for the solution of the invention. In addition, the embodiments are described with reference to the drawings, but in the description of the drawings, the same or similar parts are given the same reference numerals and repeated descriptions are omitted.

[0114] Figure 1 An example of the system configuration of the battery pack 100 is schematically shown. In the present embodiment, the battery pack 100 includes a terminal 102, a terminal 104, a battery module 112, a battery module 114, a battery module 116, a channel selector 122, a channel selector 124, a channel selector 126, a system control unit 130, and a power transmission bus 140. In the present embodiment, the power transmission bus 140 includes a low potential bus 142 and a high potential bus 144.

[0115] In this embodiment, for simplicity of description, the battery pack 100 is described as having three battery modules. However, the battery pack 100 is not limited to this embodiment. In another embodiment, the battery pack 100 may have two battery modules. In yet another embodiment, the battery pack 100 may have four or more battery modules.

[0116] The battery pack 100 may not have a combination Figure 1 In one embodiment, the battery pack 100 includes a battery module 112, a battery module 114, a battery module 116, a system control unit 130, and a power transmission bus 140. In another embodiment, the battery pack 100 includes a battery module 112, a battery module 114, a battery module 116, a channel selector 124, a channel selector 126, and a system control unit 130.

[0117] The battery pack 100 may be an example of a power storage system. The battery module 112, the battery module 114, and the battery module 116 may each be an example of a power storage device. The battery module 112, the battery module 114, and the battery module 116 may be an example of at least two power storage devices or a plurality of power storage devices. The battery module 112, the battery module 114, and the battery module 116 may be an example of an external device. The channel selector 122, the channel selector 124, and the channel selector 126 may be an example of a storage unit and an identification information conversion unit. The system control unit 130 may be an example of a control unit. The power transmission bus 140 may be an example of a power line. The low potential bus 142 may be an example of a power line. The high potential bus 144 may be an example of a power line.

[0118] In this embodiment, the battery pack 100 supplies power to an external device (sometimes referred to as a load) that uses power (sometimes referred to as discharging the battery pack 100). The battery pack 100 stores power supplied from the external device (sometimes referred to as charging the battery pack 100). For example, the battery pack 100 stores the rechargeable power from the load. The battery pack 100 may also store power supplied from a charging device. In this embodiment, the terminal 102 and the terminal 104 electrically connect the external device to the battery pack 100.

[0119] Here, the so-called "electrical connection" is not limited to the case where the first element and the second element are directly connected. A third element may also be provided between the first element and the second element. In addition, the so-called "electrical connection" is not limited to the case where the first element and the second element are physically connected. For example, the input winding and the output winding of the transformer are not physically connected, but are electrically connected. Furthermore, the so-called "electrical connection" includes not only the case where the first element and the second element are actually electrically connected, but also the case where the first element and the second element are electrically connected when the storage unit is electrically connected to the balance correction circuit.

[0120] In addition, the term "series connection" means that the first element and the second element are electrically connected in series. In addition, unless otherwise specified, the "voltage difference" between the storage cells means a value obtained by comparing the voltages of the two storage cells (sometimes referred to as the terminal voltage) and subtracting the voltage of the storage cell with a lower voltage from the voltage of the storage cell with a higher voltage.

[0121] In the present embodiment, at least one of the battery modules 112, 114, and 116 includes a plurality of storage cells connected in series. The battery modules 112, 114, and 116 may each include a plurality of storage cells connected in series. At least one of the battery modules 112, 114, and 116 may further include one or more storage cells connected in parallel with the plurality of storage cells connected in series included in each module.

[0122] In the present embodiment, at least one of the battery module 112, the battery module 114, and the battery module 116 may have a device or element for managing the charge and discharge of multiple power storage cells included in each module. The battery module 112, the battery module 114, and the battery module 116 may also each have a device or element for managing the charge and discharge of multiple power storage cells included in each module. The battery module 112, the battery module 114, and the battery module 116 may also each have (i) multiple power storage cells connected in series, and (ii) a device or element for managing the charge and discharge of the multiple power storage cells. (i) Multiple power storage cells connected in series and (ii) a device or element for managing the charge and discharge of the multiple power storage cells may be physically configured in the same housing.

[0123] In the present embodiment, the plurality of storage cells included in the battery module 112, the plurality of storage cells included in the battery module 114, and the plurality of storage cells included in the battery module 116 are connected in series. In the present embodiment, the plurality of storage cells included in the battery module 112, the plurality of storage cells included in the battery module 114, and the plurality of storage cells included in the battery module 116 are connected in series in such a manner that the battery module 112 is on the low potential side and the battery module 116 is on the high potential side.

[0124] In the present embodiment, the battery module 112, the battery module 114, and the battery module 116 are respectively arranged between the other battery modules and the terminal 102 or the terminal 104. Thus, between the multiple storage cells included in the battery module 112, the battery module 114, and the battery module 116 and the load or the charging device, one or more storage cells included in the other modules are arranged.

[0125] The rated voltage of one of the battery modules 112, 114, and 116 may be the same as or different from the rated voltage of the other of the battery modules 112, 114, and 116. The number of the plurality of power storage cells included in one of the battery modules 112, 114, and 116 may be the same as or different from the number of the plurality of power storage cells included in the other of the battery modules 112, 114, and 116.

[0126] In the present embodiment, at least one of the channel selectors 122, 124, and 126 includes, for example, a storage unit that stores first identification information and second identification information assigned to each of the plurality of storage cells included in the corresponding battery module. At least one of the channel selectors 122, 124, and 126 includes, for example, an identification information conversion unit that converts the first identification information included in a signal received from the outside (for example, the system control unit 130) into the second identification information, and converts the second identification information included in a signal sent to the outside (for example, the system control unit 130) into the first identification information, with reference to the information stored in the storage unit.

[0127] The second identification information assigned to each of the plurality of storage cells is preferably different from each other. In one embodiment, the first identification information assigned to each of the plurality of storage cells is different from all the second identification information. In another embodiment, the first identification information assigned to each of the plurality of storage cells is consistent with all the second identification information.

[0128] The first identification information may be information for the system control unit 130 to identify each of all the storage cells included in the battery pack 100. The second identification information may be information for a device or element for managing charge and discharge included in a corresponding battery module to identify each of the plurality of storage cells included in the corresponding battery module.

[0129] In the present embodiment, the channel selectors 122, 124, and 126 are respectively arranged corresponding to the battery modules 112, 114, and 116. For example, when the battery modules 112, 114, and 116 each have 10 storage cells connected in series, the system control unit 130 assigns numbers 1 to 10 to each storage cell of the battery module 112, assigns numbers 11 to 20 to each storage cell of the battery module 114, and assigns numbers 21 to 30 to each storage cell of the battery module 116.

[0130] In this case, the channel selector 122 stores, for example, 1 to 10 as the first identification information of each storage cell of the battery module 112, and stores, for example, 1 to 10 as the second identification information of each storage cell of the battery module 112. The channel selector 124 stores, for example, 11 to 20 as the first identification information of each storage cell of the battery module 114, and stores, for example, 1 to 10 as the second identification information of each storage cell of the battery module 114. The channel selector 126 stores, for example, 21 to 30 as the first identification information of each storage cell of the battery module 116, and stores, for example, 1 to 10 as the second identification information of each storage cell of the battery module 116.

[0131] When managing the inventory of battery modules, if the battery pack 100 does not have a channel selector, the inventory for the battery module 112, the inventory for the battery module 114, and the inventory for the battery module 116 must be managed as different battery modules. However, if the battery pack 100 has a channel selector, at least the inventory for the battery module 114 and the inventory for the battery module 116 can be managed as the same battery module. This can promote the standardization of battery modules and reduce the man-hours and costs for managing battery modules.

[0132] In this embodiment, the system control unit 130 controls the battery pack 100. The system control unit 130 may also manage the state of the battery pack 100. For example, the system control unit 130 manages at least one of the voltage and the state of charge (sometimes referred to as SOC) of the battery modules 112, 114, and 116.

[0133] The system control unit 130 may collect information indicating at least one of the voltage and the charge and discharge state of the battery module 112, the battery module 114, and the battery module 116. The system control unit 130 may manage the deviation of at least one of the voltage and the charge and discharge state among the battery modules 112, the battery modules 114, and the battery modules 116. The system control unit 130 may control the battery pack 100 in such a manner that the deviation of at least one of the voltage and the charge and discharge state among the battery modules 112, the battery modules 114, and the battery modules 116 satisfies a predetermined condition. The predetermined condition may be, for example, a condition that the deviation is less than a predetermined threshold value, a condition that the deviation is within a predetermined range, or the like.

[0134] In this embodiment, the power transmission bus 140 transmits power between any battery modules. When it is not necessary to transmit power between any battery modules, the low potential bus 142 and the high potential bus 144 may be electrically insulated. When power is transmitted between any battery modules, the low potential bus 142 and the high potential bus 144 may be electrically connected. The timing of transmitting power between any battery modules is determined by, for example, the system control unit 130.

[0135] Figure 2 An example of the internal structure of the battery module 112 is schematically shown. In the present embodiment, the battery module 112 includes a terminal 202, a terminal 204, an assembled battery 210, and a voltage management unit 212. In the present embodiment, the voltage management unit 212 includes a balance correction unit 220, a protection unit 230, a terminal 242, and a terminal 244.

[0136] The battery module 112 may be an example of a first power storage device. The terminal 202 may be an example of a negative terminal. The terminal 204 may be an example of a positive terminal. The assembled battery 210 may be an example of a plurality of power storage units. The voltage management unit 212 may be an example of a management device. The balance correction unit 220 may be an example of an equalization unit. The terminals 242 and 244 may be examples of power transmission and reception units.

[0137] In the present embodiment, the terminal 202 is electrically connected to the terminal 102. In the present embodiment, the terminal 204 is electrically connected to the storage cell of the battery module 114. In the present embodiment, the assembled battery 210 includes a plurality of storage cells. In the present embodiment, one end of the negative electrode side of the assembled battery 210 is electrically connected to the terminal 202, and one end of the positive electrode side of the assembled battery 210 is electrically connected to the terminal 204.

[0138] The storage unit constituting the assembled battery 210 may be a secondary battery or a capacitor. Examples of the type of secondary battery include a lithium battery, a lithium ion battery, a lithium sulfur battery, a sodium sulfur battery, a lead acid battery, a nickel hydrogen battery, a nickel cadmium battery, a redox flow battery, and a metal air battery. The type of lithium ion battery is not particularly limited. Examples of the type of lithium ion battery include an iron phosphate type, a manganese type, a cobalt type, a nickel type, and a ternary type.

[0139] The storage unit constituting the assembled battery 210 may further include a plurality of storage units. In one embodiment, a single storage unit includes a plurality of storage units connected in series. In another embodiment, a single storage unit includes a plurality of storage units connected in parallel. In yet another embodiment, a single storage unit includes a plurality of storage units connected in a matrix.

[0140] In this embodiment, the voltage management unit 212 manages the charge and discharge of the assembled battery 210. In this embodiment, the balance correction unit 220 equalizes the voltage of the assembled battery 210. The balance correction unit 220 can transmit and receive information with the system control unit 130. The balance correction unit 220 can also transmit and receive information with the system control unit 130 via the channel selector 122.

[0141] The balance correction unit 220 may be physically configured in the same housing as the channel selector 122. The balance correction unit 220 may be physically configured in a different housing than the channel selector 122. The balance correction unit 220 may be physically configured on the same substrate as the channel selector 122. The balance correction unit 220 may be physically configured on a different substrate than the channel selector 122. Details of an embodiment of the balance correction unit 220 will be described below.

[0142] The protection unit 230 protects the assembled battery 210 from at least one of overcurrent, overvoltage, and overdischarge. As the protection unit 230, for example, a known overcurrent / overvoltage protection circuit as disclosed in Japanese Patent Laid-Open No. 2009-183141 can be used.

[0143] In the present embodiment, the terminal 242 is electrically connected to the low potential bus 142. In addition, the terminal 242 is electrically connected to the negative terminal of the assembled battery 210. In the present embodiment, the terminal 244 is electrically connected to the high potential bus 144. In addition, the terminal 244 is electrically connected to the positive terminal of the assembled battery 210. In the present embodiment, the positive terminal and the negative terminal of the assembled battery 210 of the battery module 112 are physically connected to the power transmission bus 140. Thus, the positive terminal and the negative terminal of the assembled battery 210 of the battery module 112 are always electrically connected to the power transmission bus 140.

[0144] Thus, the assembled battery 210 of the battery module 112 can transmit / receive power to / from at least one of the other battery modules via the terminals 242 and 244 and the power transmission bus 140. For example, the terminals 242 and 244 (i) transmit the power of the assembled battery 210 to at least one of the battery module 114 and the battery module 116, or (ii) receive the power supplied to the cells of the assembled battery 210 from at least one of the battery module 114 and the battery module 116, without disconnecting or switching the electrical connection between (a) the assembled battery 210 and (b-1) a load using the power of the assembled battery 210 or (b-2) a charging device that charges the assembled battery 210.

[0145] Figure 3 An example of the internal structure of the battery module 114 is schematically shown. In the present embodiment, the battery module 114 includes a terminal 202, a terminal 204, an assembled battery 210, and a voltage management unit 312. In the present embodiment, the voltage management unit 312 includes a balance correction unit 220, a protection unit 230, a DC-DC converter 330, a terminal 242, and a terminal 244. In addition, the battery module 116 may also have the same internal structure as the battery module 114.

[0146] In this embodiment, the voltage management unit 312 is different from the voltage management unit 212 in that: (i) the DC-DC converter 330 is provided; (ii) the DC-DC converter 330 has the terminal 242 and the terminal 244; (iii) the terminal 242 is not physically connected to the negative terminal of the assembled battery 210; and (iv) the terminal 244 is not physically connected to the positive terminal of the assembled battery 210. In the voltage management unit 312, the components other than the above-mentioned differences may have the same features as those of the voltage management unit 212.

[0147] The battery module 114 may be an example of a second power storage device. The voltage management unit 312 may be an example of a management device. The DC-DC converter 330 may be an example of a power transmission and reception unit. The DC-DC converter 330 may be an example of a voltage adjustment unit.

[0148] In the present embodiment, the DC-DC converter 330 transmits / receives electric power between the assembled battery 210 of the battery module 114 and at least one of the other battery modules via the power transmission bus 140. For example, the DC-DC converter 330 (i) transmits the electric power of the assembled battery 210 to at least one of the battery module 112 and the battery module 116, or (ii) receives the electric power supplied to the assembled battery 210 from at least one of the battery module 112 and the battery module 116, without disconnecting or switching the electrical connection between (a) the assembled battery 210 and (b-1) the load using the electric power of the assembled battery 210 or (b-2) the charging device charging the assembled battery 210. The DC-DC converter 330 can also adjust the voltage of the transmitted or received electric power to an arbitrary value.

[0149] In the present embodiment, the DC-DC converter 330 may start power transmission or power reception based on a received signal for starting power transmission or power reception. The DC-DC converter 330 may stop power transmission or power reception based on a received signal for stopping power transmission or power reception. For example, the DC-DC converter 330 starts power transmission or power reception, or stops power transmission or power reception based on a signal φ32 from the system control unit 130. The signal φ32 may be a signal including information indicating the start of an action, and information indicating which action of the power transmission action and the power reception action should be performed. The signal φ32 may be a signal indicating the start of a power transmission action. The signal φ32 may also be a signal indicating the start of a power reception action. The signal φ32 may also be information indicating the stop of the current action.

[0150] The details of the DC-DC converter 330 are not particularly limited, and the DC-DC converter 330 may be an isolated DC-DC converter 330 . The DC-DC converter 330 may be a bidirectional DC-DC converter. The voltage management unit 312 may include a plurality of DC-DC converters 330 .

[0151] The DC-DC converter 330 may be a forward DC-DC converter or a flyback DC-DC converter. In the battery pack 100, the rated voltages of the battery modules 112, 114, and 116 may be different. Therefore, the DC-DC converter 330 is preferably a flyback DC-DC converter that can cope with a wide voltage range.

[0152] The DC-DC converter 330 may be a self-excited DC-DC converter or an externally excited DC-DC converter. The DC-DC converter 330 may be a DC-DC converter of an asynchronous rectification mode or a DC-DC converter of a synchronous rectification mode. The control method of the DC-DC converter 330 is not particularly limited, and preferably a constant current control is implemented. Details of an embodiment of the DC-DC converter 330 will be described below.

[0153] Combination Figure 2 The battery module 112 described above does not include the DC-DC converter 330. However, the battery module 112 is not limited to the above embodiment. The battery module 112 may also have the same configuration as the battery module 114. Preferably, at least one of the battery module 112, the battery module 114, and the battery module 116 includes a bidirectional DC-DC converter.

[0154] Figure 4 An example of the internal structure of the balance correction unit 220 is schematically shown. Figure 4 An example of the internal structure of the balance correction unit 220 is shown together with the terminal 202, the terminal 204, and the assembled battery 210. In the present embodiment, the assembled battery 210 includes a plurality of storage cells connected in series, including the storage cell 412, the storage cell 414, the storage cell 416, and the storage cell 418. In the present embodiment, the balance correction unit 220 includes a plurality of balance correction circuits, including the balance correction circuit 432, the balance correction circuit 434, and the balance correction circuit 436. The balance correction circuit 432, the balance correction circuit 434, and the balance correction circuit 436 may be an example of a balance correction device.

[0155] In the present embodiment, the balance correction circuit 432 equalizes the voltages of the storage cell 412 and the storage cell 414. In the present embodiment, the balance correction circuit 432 is electrically connected to one end (sometimes referred to as the positive electrode side) on the terminal 204 side of the storage cell 414. The balance correction circuit 432 is electrically connected to a connection point 443 on the positive electrode side of the storage cell 412 and one end (sometimes referred to as the negative electrode side) on the terminal 202 side of the storage cell 414. The balance correction circuit 432 is electrically connected to the negative electrode side of the storage cell 412.

[0156] In this embodiment, the balance correction circuit 432 is described as equalizing the voltages of two adjacent storage cells. However, the balance correction circuit 432 is not limited to this embodiment. In another embodiment, the balance correction circuit 432 may also equalize the voltages of any two storage cells among three or more storage cells connected in series.

[0157] In this embodiment, the balance correction circuit 434 equalizes the voltages of the storage cells 414 and 416. The balance correction circuit 434 is electrically connected to the connection point 443, the connection point 445 between the positive electrode side of the storage cell 414 and the negative electrode side of the storage cell 416, and the connection point 447 between the positive electrode side of the storage cell 416 and the negative electrode side of the storage cell 418. The balance correction circuit 434 may have the same configuration as the balance correction circuit 432.

[0158] In this embodiment, the balance correction circuit 436 equalizes the voltages of the storage cells 416 and 418. The balance correction circuit 436 is electrically connected to the connection point 445, the connection point 447, and the positive electrode side of the storage cell 418. The balance correction circuit 436 may have the same configuration as the balance correction circuit 432.

[0159] Figure 5 An example of the internal structure of the balance correction circuit 432 is schematically shown. Figure 5 An example of the internal structure of the balance correction circuit 432 is shown together with the storage cell 412 and the storage cell 414. In the present embodiment, the balance correction circuit 432 includes an inductor 550, a switching element 552, a switching element 554, and an equalization control unit 570. The balance correction circuit 432 may also include a diode 562 and a diode 564. The balance correction circuit 432 may also include a voltage monitoring unit 580. The voltage monitoring unit 580 includes, for example, a voltage detection unit 582, a voltage detection unit 584, and a difference detection unit 586. The balance correction circuit 432 may also include a module control unit 590.

[0160] The equalization control unit 570 and the switch elements 554 and 552 may be physically arranged on the same substrate or on physically different substrates. The equalization control unit 570 and the module control unit 590 may be physically formed on the same substrate or on physically different substrates.

[0161] In this embodiment, the case where the balance correction circuit 432 includes the equalization control unit 570 and the module control unit 590 is described. However, the balance correction circuit 432 is not limited to this embodiment. In another embodiment, the equalization control unit 570 may include at least a part of the function of the module control unit 590, and the balance correction circuit 432 may not include the module control unit 590. In still another embodiment, the module control unit 590 may include at least a part of the function of the equalization control unit 570, and the balance correction circuit 432 may not include the equalization control unit 570.

[0162] In the present embodiment, a case is described in which (i) a resistor provided at an appropriate position in a first circuit including the power storage cell 414, the inductor 550, and the switching element 554 or the diode 564, and (ii) a resistor provided at an appropriate position in a second circuit including the power storage cell 412, the inductor 550, and the switching element 552 or the diode 562 are used as a current detection unit for detecting an inductor current flowing through the inductor 550. The resistor may be a shunt resistor.

[0163] However, the current detection unit is not limited to this embodiment. In another embodiment, at least one of the internal resistance of the switch element 552 and the internal resistance of the switch element 554 may be used as the current detection unit. In another embodiment, the current detection unit may be an ammeter that detects the current flowing through the inductor 550 and transmits a signal including information indicating the current value of the inductor 550 to the equalization control unit 570.

[0164] One of the storage cells 412 and the storage cells 414 may be an example of a first storage cell constituting a plurality of storage cells. The other of the storage cells 412 and the storage cells 414 may be an example of a second storage cell constituting a plurality of storage cells. The balance correction circuit 432 may be an example of a balance correction device. One of the switching elements 552 and the switching elements 554 may be an example of a first switching element. The other of the switching elements 552 and the switching elements 554 may be an example of a second switching element. One of the diodes 562 and the diodes 564 may be an example of a rectifier or a first rectifier. The other of the diodes 562 and the diodes 564 may be an example of a rectifier or a second rectifier. The equalization control unit 570 may be an example of an equalization unit.

[0165] In this embodiment, the balance correction circuit 432 is electrically connected to (i) the positive side of the storage cell 414, (ii) the connection point 443 between the negative side of the storage cell 414 and the positive side of the storage cell 412, and (iii) the negative side of the storage cell 412. Thus, a first open-close circuit including the storage cell 414, the switching element 554, and the inductor 550 is formed. In addition, a second open-close circuit including the storage cell 412, the inductor 550, and the switching element 552 is formed. The connection point 443 may be an example of a connection point between one end of the first storage cell and one end of the second storage cell.

[0166] In the present embodiment, the inductor 550 is disposed between the power storage cell 414 and the switch element 554, and is connected in series with the power storage cell 414 and the switch element 554. Thus, the inductor 550 and the switch element 554 cooperate to adjust the voltage of at least one of the power storage cell 412 and the power storage cell 414. In the present embodiment, one end of the inductor 550 is electrically connected to the connection point 443. The other end of the inductor 550 is electrically connected to the connection point 545 between the switch element 552 and the switch element 554.

[0167] According to the present embodiment, the switch element 552 and the switch element 554 alternately repeat the on and off operations (sometimes referred to as on / off operations), and the inductor 550 generates the inductor current I LThus, electric energy can be transferred between the electric storage cell 412 and the electric storage cell 414 via the inductor 550. As a result, the voltages of the electric storage cell 412 and the electric storage cell 414 can be equalized.

[0168] In this embodiment, the switch element 552 is electrically connected between the other end of the inductor 550 and the negative electrode side of the storage cell 412. The switch element 552 receives the drive signal φ52 from the equalization control unit 570, and performs an on-action or an off-action based on the drive signal φ52. The second opening and closing circuit opens and closes with the action of the switch element 552. The switch element 552 can be a semiconductor transistor such as a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor).

[0169] In this embodiment, the switch element 554 is electrically connected between the other end of the inductor 550 and the positive electrode side of the storage cell 414. The switch element 554 receives a drive signal φ54 from the equalization control unit 570, and performs an on-action or an off-action based on the drive signal φ54. The first opening and closing circuit is opened and closed in accordance with the action of the switch element 554. The switch element 554 can be a semiconductor transistor such as a MOSFET.

[0170] In the present embodiment, the diode 562 is electrically connected between the other end of the inductor 550 and the negative electrode side of the power storage unit 412. The diode 562 is arranged in parallel with the switch element 552. When the switch element 552 is a semiconductor element such as a MOSFET, the diode 562 may be a parasitic diode equivalently formed between the source and the drain of the switch element 552.

[0171] In the present embodiment, the diode 562 allows current to flow in the direction from the negative electrode side of the storage cell 412 toward the other end of the inductor 550. On the other hand, the diode 562 does not allow current to flow in the direction from the other end of the inductor 550 toward the negative electrode side of the storage cell 412. That is, the current flowing in the direction from the negative electrode side of the storage cell 412 toward the positive electrode side of the storage cell 412 can pass through the diode 562, but the current flowing in the direction from the positive electrode side of the storage cell 412 toward the negative electrode side of the storage cell 412 cannot pass through the diode 562.

[0172] In the present embodiment, the diode 564 is electrically connected between the other end of the inductor 550 and the positive electrode side of the power storage cell 414. The diode 564 is arranged in parallel with the switch element 554. When the switch element 554 is a semiconductor element such as a MOSFET, the diode 564 may be a parasitic diode equivalently formed between the source and the drain of the switch element 554.

[0173] In the present embodiment, the diode 564 allows current to flow in the direction from the other end of the inductor 550 toward the positive electrode side of the storage cell 414. On the other hand, the diode 564 does not allow current to flow in the direction from the positive electrode side of the storage cell 414 toward the other end of the inductor 550. That is, the current flowing in the direction from the negative electrode side of the storage cell 414 toward the positive electrode side of the storage cell 414 can pass through the diode 564, but the current flowing in the direction from the positive electrode side of the storage cell 414 toward the negative electrode side of the storage cell 414 cannot pass through the diode 564.

[0174] The balance correction circuit 432 has the diode 562 and the diode 564. Therefore, even when the switch element 552 and the switch element 554 are both in the off state, the inductor current I remains in the first circuit or the second circuit. L In this case, the inductor current I L The current I can also continue to flow in the circuit through the diode 562 or the diode 564. Thus, the balance correction circuit 432 can make full use of the inductor current I temporarily generated by the inductor 550. L In addition, the balance correction circuit 432 can suppress the blocking inductor current I L In case of surge voltage generation.

[0175] In this embodiment, the equalization control unit 570 controls at least one of the switch element 552 and the switch element 554 to control the balance correction circuit 432. For example, the equalization control unit 570 controls at least one of the switch element 552 and the switch element 554 based on the operation control signal φ58 from the module control unit 590.

[0176] In this embodiment, the equalization control unit 570 supplies the switch element 552 with a drive signal φ52 for controlling the on / off operation of the switch element 552. In addition, the equalization control unit 570 supplies the switch element 554 with a drive signal φ54 for controlling the on / off operation of the switch element 554.

[0177] In one embodiment, the equalization control unit 570 supplies the drive signal φ52 and the drive signal φ54 in such a manner that the switch element 552 and the switch element 554 alternately (or complementarily) repeat the on / off operation. Thus, during the operation of the balance correction circuit 432, the switching operation of alternately switching the state where the current flows through the first circuit and the state where the current flows through the second circuit is repeated.

[0178] In another embodiment, the equalization control unit 570 supplies the drive signal φ52 and the drive signal φ54 in such a manner that one of the switch element 552 and the switch element 554 repeats the on / off operation and the other of the switch element 552 and the switch element 554 remains in the off state. Thus, during the operation of the balance correction circuit 432, the switching operation of alternately switching the state where the current flows through the first circuit and the state where the current flows through the second circuit is repeated.

[0179] For example, when the action control signal φ58 indicates that the charge is transferred from the storage cell 414 to the storage cell 412, the equalization control unit 570 supplies the drive signal φ52 and the drive signal φ54 in such a manner that the switch element 554 repeats the on / off operation and the switch element 552 is maintained in the off state. In this case, the inductor current flows through the second circuit via the diode 562. On the other hand, when the action control signal φ58 indicates that the charge is transferred from the storage cell 412 to the storage cell 414, the equalization control unit 570 supplies the drive signal φ52 and the drive signal φ54 in such a manner that the switch element 552 repeats the on / off operation and the switch element 554 is maintained in the off state. In this case, the inductor current flows through the first circuit via the diode 564.

[0180] The equalization control unit 570 may combine the drive signal φ52 and the drive signal φ54 to generate various control signals for controlling the balance correction circuit 432. In one embodiment, the equalization control unit 570 generates a first control signal for turning on the switch element 554 and turning off the switch element 552. In another embodiment, the equalization control unit 570 generates a second control signal for turning off the switch element 554 and turning on the switch element 552. In yet another embodiment, the equalization control unit 570 generates a third control signal for turning off the switch element 554 and turning off the switch element 552. The first control signal, the second control signal, and the third control signal may include the drive signal φ52 and the drive signal φ54, respectively.

[0181] The equalization control unit 570 controls the balance correction circuit 432 so that the balance correction circuit 432 repeats the following switching operation when the balance correction circuit 432 is in an activated state, for example. Also, the equalization control unit 570 controls the balance correction circuit 432 so that the balance correction circuit 432 stops switching operation when the balance correction circuit 432 is in a stopped state, for example.

[0182] For example, the equalization control unit 570 supplies the drive signal φ52 and the drive signal φ54 to the switch element 552 and the switch element 554 so that the balance correction circuit 432 repeats the switching operation at a predetermined cycle during the operation period of the balance correction circuit 432. Here, the so-called "predetermined cycle" includes not only the case where the switching operation is repeated at a predetermined cycle, but also the case where the cycle is changed by a predetermined arbitrary algorithm or the case where the cycle is changed by a pre-configured arbitrary analog circuit.

[0183] For example, even when the period of the next cycle is determined based on certain information of the current cycle, a predetermined specific algorithm, or a specific analog circuit, the period can be an example of a “predetermined period”. In addition, even when the timing of switching at least one of the first action, the second action, and the third action included in the switching action to another action is determined based on a specific algorithm or a specific analog circuit, the period of the switching action can be an example of a “predetermined period”. The period is determined, for example, based on (i) at least one of the power storage unit 412 and the power storage unit 414, (ii) the current value of the current flowing through the inductor 550, and (iii) a combination of (i) and (ii).

[0184] The switching action may include: (i) a first action, in which the switch element 554 performs a connection action and the switch element 552 performs a disconnection action; and (ii) a second action, in which the switch element 554 performs a disconnection action and the switch element 552 performs a connection action. In addition to the first action and the second action, the switching action may also include a third action in which both the switch element 554 and the switch element 552 perform a disconnection action. The order of the first action, the second action, and the third action may be determined arbitrarily, but it is preferred that the second action be performed after the first action. The switching action may also include other actions different from the first action, the second action, and the third action.

[0185] In the present embodiment, the voltage monitoring unit 580 monitors the voltage of at least one of the storage cell 412 and the storage cell 414. In the present embodiment, the voltage monitoring unit 580 detects the voltage of the storage cell 412 and the voltage of the storage cell 414 using the voltage detection unit 582 and the voltage detection unit 584. The voltage monitoring unit 580 inputs the voltage of the storage cell 412 and the voltage of the storage cell 414 to the difference detection unit 586, and detects the voltage difference between the storage cell 412 and the storage cell 414. The voltage monitoring unit 580 generates a signal φ56 indicating the detected voltage difference and sends it to the module control unit 590. The signal φ56 may also include information indicating which voltage is larger between the voltage of the storage cell 412 and the voltage of the storage cell 414. The signal φ56 may also include information indicating the voltage of the storage cell 412 and the voltage of the storage cell 414.

[0186] In the present embodiment, the module control unit 590 controls the balance correction circuit 432. The module control unit 590 may control the balance correction circuit 432 via the equalization control unit 570. The module control unit 590 may send information indicating the voltage of the storage cell 412 and the voltage of the storage cell 414 to the system control unit 130. The module control unit 590 may send information indicating the voltage of the storage cell 412 and the voltage of the storage cell 414 to the system control unit 130 via a corresponding channel selector (e.g., the channel selector 122, the channel selector 124, or the channel selector 126).

[0187] In one embodiment, the module control unit 590 determines the direction in which the charge is to be moved. For example, the module control unit 590 determines whether to (i) move the charge from the storage cell 414 to the storage cell 412 or (ii) move the charge from the storage cell 412 to the storage cell 414 based on the voltage or SOC of the storage cell 412 and the storage cell 414. The module control unit 590 may send an action control signal φ58 including information indicating the direction in which the charge is to be moved to the equalization control unit 570.

[0188] In another embodiment, the module control unit 590 estimates the net amount of charge transferred between the power storage unit 412 and the power storage unit 414 (sometimes referred to as the amount of charge transferred). For example, the module control unit 590 estimates the amount of charge transferred based on (i) the operating time of the balance correction circuit 432 and (ii) the measured value or the estimated value of the current value flowing through the inductor 550. The module control unit 590 may also control the balance correction circuit 432 based on the estimated value of the amount of charge transferred. The module control unit 590 may also send the operation control signal φ58 including information indicating the estimated value of the amount of charge transferred to the equalization control unit 570. The module control unit 590 may also be an example of a device for estimating the amount of charge transferred, which estimates the net amount of charge transferred between the two power storage units during the operating period of the balance correction device based on the operating time of the balance correction device and the valley value of the absolute value of the current value of the inductor current during the operating period of the balance correction device or its target condition.

[0189] The module control unit 590 may also estimate the time from the activation to the stop of the balance correction circuit 432. For example, the module control unit 590 estimates the time from the activation to the stop of the balance correction circuit 432 based on the voltage difference between the storage cell 414 and the storage cell 412 immediately before or immediately after the activation of the balance correction circuit 432 and the estimated value of the amount of charge transfer. The module control unit 590 may also be an example of an operation time estimation device that estimates the time or moment until the balance correction device stops based on the voltage difference between the two storage cells that are the operation targets of the balance correction device and the valley value of the absolute value of the current value of the inductor current during the operation of the balance correction device or its target condition.

[0190] In another embodiment, the module control unit 590 determines whether to activate the balance correction circuit 432 and whether to stop the balance correction circuit 432. The module control unit 590 sends an action control signal φ58 to the equalization control unit 570, and the action control signal φ58 includes information indicating whether to activate the balance correction circuit 432 and whether to stop the balance correction circuit 432.

[0191] [Timing of Activating the Balance Correction Circuit 432]

[0192] In this embodiment, the module control unit 590 transmits the operation control signal φ58 including information indicating that the stopped balance correction circuit 432 is activated to the equalization control unit 570. For example, the module control unit 590 transmits the operation control signal φ58 to the equalization control unit 570 at the time of activating the balance correction circuit 432. The module control unit 590 may also transmit the operation control signal φ58 including information indicating the time of activating the balance correction circuit 432 and information indicating that the balance correction circuit 432 is activated at the time to the equalization control unit 570.

[0193] The module control unit 590 may determine the timing to activate the stopped balance correction circuit 432 based on the voltage or SOC of the storage cell 412 and the storage cell 414. For example, the module control unit 590 may determine to activate the balance correction circuit 432 when the voltage or SOC of at least one of the storage cell 412 and the storage cell 414 satisfies a predetermined first condition. The first condition may be, for example, the following conditions, i.e., (i) the difference between the voltage or SOC of the storage cell 412 and the storage cell 414 is greater than a predetermined first value; and (ii) the voltage or SOC of at least one of the storage cell 412 and the storage cell 414 is consistent with a value specified according to the voltage or SOC of the storage cell 412 and the storage cell 414.

[0194] [Time to Stop the Balance Correction Circuit 432]

[0195] In this embodiment, the module control unit 590 transmits the action control signal φ58 including information indicating that the balance correction circuit 432 is stopped to the equalization control unit 570. For example, the module control unit 590 transmits the action control signal φ58 to the equalization control unit 570 at the time of stopping the balance correction circuit 432. The module control unit 590 may also transmit the action control signal φ58 including information indicating the time of stopping the balance correction circuit 432 and information indicating that the balance correction circuit 432 is stopped at the time to the equalization control unit 570.

[0196] In this embodiment, the balance correction circuit 432 uses the inductor 550, the switch element 552, and the switch element 554 to equalize the voltages of the storage cells 412 and 414. However, the balance correction circuit 432 is not limited to this embodiment. The balance correction circuit 432 can equalize the voltages of the storage cells 412 and 414 by a known equalization method or an equalization method to be developed in the future. In one embodiment, a balance correction circuit that uses a resistor to release the energy of a storage cell with a high voltage is used. In another embodiment, a balance correction circuit that uses a transformer to move charge is used.

[0197] Figure 6 An example of the internal structure of the DC-DC converter 330 is schematically shown. In the present embodiment, the DC-DC converter 330 includes a transformer 610. In the present embodiment, the DC-DC converter 330 includes a switching element 622, a diode 634, a discharge control unit 642, a current detection unit 652, and a capacitor 662. Thus, the power of the assembled battery 210 can be supplied to other battery modules.

[0198] In the present embodiment, the DC-DC converter 330 includes a switching element 624, a diode 632, a charging control unit 644, a current detection unit 654, and a capacitor 664. Thus, the assembled battery 210 can be charged using electric power supplied from other battery modules.

[0199] In this embodiment, the transformer 610 has two coils. The transformer 610 transmits energy from one coil to the other coil. In addition, the transformer 610 transmits energy from the other coil to one coil.

[0200] In this embodiment, one end of one coil of transformer 610 is electrically connected to the positive terminal of assembled battery 210 . The other end of one coil of transformer 610 is electrically connected to one end of switching element 622 . The other end of switching element 622 is electrically connected to the negative terminal of assembled battery 210 .

[0201] In the present embodiment, one end of the other coil of the transformer 610 is electrically connected to the terminal 244. The other end of the other coil of the transformer 610 is electrically connected to one end of the switching element 624. The other end of the switching element 624 is electrically connected to the terminal 242.

[0202] In this embodiment, the switch element 622 performs an on-state operation and an off-state operation based on a signal from the discharge control unit 642. The switch element 622 may be a semiconductor transistor such as a MOSFET. In this embodiment, the switch element 624 may perform an on-state operation and an off-state operation based on a signal from the charge control unit 644. The switch element 624 may be a semiconductor transistor such as a MOSFET.

[0203] In the present embodiment, the diode 632 is electrically connected between the other end of one coil of the transformer 610 and the negative terminal of the assembled battery 210. The diode 632 is arranged in parallel with the switch element 622. When the switch element 622 is a semiconductor element such as a MOSFET, the diode 632 may be a parasitic diode equivalently formed between the source and the drain of the switch element 622. In the present embodiment, the diode 632 allows current to flow in the direction from the negative terminal of the assembled battery 210 to the positive terminal of the assembled battery 210. On the other hand, the diode 632 does not allow current to flow in the direction from the positive terminal of the assembled battery 210 to the negative terminal of the assembled battery 210.

[0204] In the present embodiment, the diode 634 is electrically connected between the other end of the other coil of the transformer 610 and the terminal 242. The diode 634 is arranged in parallel with the switch element 624. When the switch element 624 is a semiconductor element such as a MOSFET, the diode 634 may also be a parasitic diode equivalently formed between the source and the drain of the switch element 624. In the present embodiment, the diode 634 allows current to flow in the direction from the terminal 242 to the terminal 244. On the other hand, the diode 634 does not allow current to flow in the direction from the terminal 244 to the terminal 242.

[0205] In this embodiment, the discharge control unit 642 controls the switch element 622. For example, the discharge control unit 642 generates a signal for controlling the on and off operation of the switch element 622, and transmits the generated signal to the switch element 622. The discharge control unit 642 may include a pulse width modulator. The discharge control unit 642 may generate the signal using the pulse width modulator.

[0206] In one embodiment, the discharge control unit 642 obtains information indicating the magnitude of the current flowing through the transformer 610 from the current detection unit 652. The discharge control unit 642 may also generate a signal for controlling the on and off operations of the switch element 622 based on the information indicating the magnitude of the current flowing through the transformer 610.

[0207] For example, the discharge control unit 642 generates a signal for controlling the on and off operations of the switch element 622 so that the magnitude of the current flowing through one coil of the transformer 610 satisfies a predetermined condition. The predetermined condition may be a condition that the magnitude of the current flowing through one coil of the transformer 610 is substantially equal to the rated current value of the DC-DC converter 330.

[0208] In another embodiment, the discharge control unit 642 generates a signal for controlling the on and off operation of the switch element 622 in such a manner that the voltage between the terminal 242 and the terminal 244 satisfies a predetermined condition. The predetermined condition may be, for example, the following conditions, namely: the voltage between the terminal 242 and the terminal 244 is substantially equal to a predetermined value; and the voltage between the terminal 242 and the terminal 244 is within a predetermined range.

[0209] In this embodiment, the charging control unit 644 controls the switching element 624. For example, the charging control unit 644 generates a signal for controlling the on and off operation of the switching element 624, and transmits the generated signal to the switching element 624. The charging control unit 644 may include a pulse width modulator. The charging control unit 644 may generate the signal using the pulse width modulator.

[0210] In one embodiment, the charging control unit 644 obtains information indicating the magnitude of the current flowing through the transformer 610 from the current detection unit 652. The charging control unit 644 may also generate a signal for controlling the on and off operations of the switching element 624 based on the information indicating the magnitude of the current flowing through the transformer 610.

[0211] For example, the charging control unit 644 generates a signal for controlling the on and off operation of the switching element 624 so that the magnitude of the current flowing through the other coil of the transformer 610 satisfies a predetermined condition. The predetermined condition may be a condition that the magnitude of the current flowing through the other coil of the transformer 610 is substantially equal to the rated current value of the DC-DC converter 330.

[0212] In another embodiment, the charge control unit 644 generates a signal for controlling the on and off operations of the switch element 624 so that the voltage applied to the assembled battery 210 satisfies a predetermined condition. The predetermined condition may be, for example, the following conditions: the voltage applied to the assembled battery 210 is substantially equal to a predetermined value; and the voltage applied to the assembled battery 210 is within a predetermined range.

[0213] In the present embodiment, the current detection unit 652 detects the current flowing through one coil of the transformer 610. The current detection unit 652 provides information indicating the magnitude of the detected current to the discharge control unit 642. In the present embodiment, the current detection unit 654 detects the current flowing through the other coil of the transformer 610. The current detection unit 652 provides information indicating the magnitude of the detected current to the discharge control unit 642.

[0214] In the present embodiment, one end of the capacitor 662 is electrically connected to one end of one coil of the transformer 610. The other end of the capacitor 662 is electrically connected to the other end of the switch element 622. The capacitor 662 is arranged in parallel with the assembled battery 210. In the present embodiment, one end of the capacitor 664 is electrically connected to one end of the other coil of the transformer 610. The other end of the capacitor 662 is electrically connected to the other end of the switch element 624. The capacitor 664 is arranged in parallel with the assembled battery 210.

[0215] Figure 7 An example of the internal structure of the system control unit 130 is schematically shown. In this embodiment, the system control unit 130 includes a module management unit 710, a module selection unit 720, and a signal generation unit 730. The module selection unit 720 may be an example of a determination unit. The signal generation unit 730 may be an example of a command generation unit.

[0216] The module management unit 710 manages the states of the battery modules of the battery pack 100. For example, the module management unit 710 collects information indicating at least one of the voltage and the charge and discharge state of the battery modules 112, 114, and 116. The module management unit 710 may collect information indicating at least one of the voltage and the charge and discharge state for each of the plurality of storage cells constituting the assembled battery 210 of each module. The module management unit 710 may also store the information indicating at least one of the voltage and the charge and discharge state of each battery module in a storage device.

[0217] The module management unit 710 may obtain information indicating at least one of the voltage and the charge and discharge state of each battery module from the balance correction unit 220 of each battery module via the channel selector corresponding to each battery module. The module management unit 710 may also obtain information indicating at least one of the voltage and the charge and discharge state of each module from the module control unit 590 of the balance correction unit 220 of each module.

[0218] In this embodiment, the module selection unit 720 determines whether to transfer power from one or more battery modules to one or more other battery modules. The module selection unit 720 can select a battery module on the power transmission side and a battery module on the power reception side.

[0219] For example, the module selection unit 720 determines (i) a battery module that transmits power to the power transmission bus 140 and (ii) a battery module that receives power from the power transmission bus 140 among the battery modules 112, the battery modules 114, and the battery modules 116, based on the voltages or charge / discharge states of the plurality of power storage cells of the assembled batteries 210 constituting each of the battery modules 112, the battery modules 114, and the battery modules 116. For example, the module selection unit 720 determines the battery modules based on the voltages or charge / discharge states of the assembled batteries 210 of each of the battery modules.

[0220] In the present embodiment, the signal generating unit 730 generates a signal for controlling the battery module 112, the battery module 114, and the battery module 116. The signal generating unit 730 may transmit the generated signal to the battery module to which the signal is sent.

[0221] In the present embodiment, the signal generation unit 730 generates a signal including at least one of (i) a command for causing the DC-DC converter 330 of the battery module that transmits power to the power transmission bus 140 to start a power transmission operation, and (ii) a command for causing the DC-DC converter 330 of the battery module that receives power from the power transmission bus 140 to start a power reception operation. The signal generation unit 730 may generate the signal based on the voltage or charge / discharge state of each of the plurality of storage cells constituting the assembled battery 210 of each of the battery modules. The signal generation unit 730 may generate the signal based on the voltage or charge / discharge state of the assembled battery 210 of each of the battery modules.

[0222] In the present embodiment, the signal generation unit 730 generates a signal including at least one of (i) a command for causing the DC-DC converter 330 of the battery module that transmits power to the power transmission bus 140 to stop the power transmission operation, and (ii) a command for causing the DC-DC converter 330 of the battery module that receives power from the power transmission bus 140 to stop the power reception operation. The signal generation unit 730 may generate the signal based on the voltage or charge / discharge state of each of the plurality of storage cells constituting the assembled battery 210 of each of the battery modules. The signal generation unit 730 may generate the signal based on the voltage or charge / discharge state of the assembled battery 210 of each of the battery modules.

[0223] Figure 8 An example of a system configuration of an electric vehicle 800 is schematically shown. In this embodiment, the electric vehicle 800 includes a battery pack 100 and a motor 810. The electric vehicle 800 may be an example of an electric device that operates using electricity. The motor 810 may be an example of a load that uses the power of the battery pack 100.

[0224] In the present embodiment, the battery module 112, the battery module 114, and the battery module 116 are arranged at different positions of the electric vehicle 800. Depending on the position where the battery module is arranged, the environment around the battery module is different. As the environment, for example, it can be temperature, humidity, temperature change, humidity change, etc. Therefore, the deviation of the degradation state between the plurality of battery modules increases with the passage of time. As a result, there is a case where the balance of the voltage or SOC between the plurality of battery modules deviates from the initial set value.

[0225] However, according to the battery pack 100 of this embodiment, when the voltage or SOC between the plurality of battery modules is out of balance, power can be transmitted / received between the plurality of battery modules. Thus, the performance of the battery pack 100 is restored. In addition, the battery pack 100 can be used efficiently.

[0226] Fig. 9 An example of the system configuration of the battery pack 900 is schematically shown. Figure 1 100 includes a system control unit 130 and a plurality of battery modules, each battery module includes an assembled battery 210 and a balance correction unit 220, and the assembled batteries 210 of each battery module are connected in series. The battery pack 100 includes a channel selector corresponding to each battery module.

[0227] The battery pack 900 of this embodiment is different from the battery pack 100 in that at least two of the plurality of battery modules are connected in parallel. In this embodiment, the battery pack 900 includes a system control unit 130, a battery module 920, and a battery module 940. The battery module 920 and the battery module 940 each include an assembled battery 210 and a balance correction unit 220.

[0228] In this embodiment, the battery pack 900 includes a channel selector 932 corresponding to the battery module 920 and a channel selector 934 corresponding to the battery module 940. The channel selectors 932 and 934 may have the same configuration as the channel selector 122, the channel selector 124, or the channel selector 126. The channel selectors 932 and 934 may transmit and receive information with the system control unit 130.

[0229] In this embodiment, the battery pack 900 includes a current detection unit 942 that detects the current flowing through the assembled battery 210 of the battery module 920, and a current detection unit 944 that detects the current flowing through the assembled battery 210 of the battery module 940. The current detection unit 942 and the current detection unit 944 can send information indicating the magnitude of the detected current to the system control unit 130. Each of the current detection unit 942 and the current detection unit 944 can send information indicating the magnitude of the detected current to the system control unit 130 via the channel selectors 932 and 934, respectively.

[0230] In this embodiment, the battery pack 900 includes a switch 952 for switching the electrical connection relationship between the terminal 104 and the assembled battery 210 of the battery module 920, and a switch 954 for switching the electrical connection relationship between the terminal 104 and the assembled battery 210 of the battery module 940. The switch 952 and the switch 954 can switch the connection relationship based on a signal from the system control unit 130. Each of the switch 952 and the switch 954 can receive a signal from the system control unit 130 via the channel selector 932 and the channel selector 934, respectively. In addition, the switch 952 can also be arranged between the terminal 102 and the assembled battery 210 of the battery module 920. The switch 954 can also be arranged between the terminal 102 and the assembled battery 210 of the battery module 940.

[0231] The present invention has been described above using embodiments, but the protection scope of the present invention is not limited to the scope described in the embodiments. It is clear to those skilled in the art that various changes or improvements can be applied to the embodiments. In addition, the matters described in a specific embodiment can be applied to other embodiments within the scope that is not technically contradictory. In addition, each constituent element may also have the same features as other constituent elements with the same name and different figure numerals. It can be seen from the description of the claims that the method to which such changes or improvements are applied may also be included in the protection scope of the present invention.

[0232] It should be noted that the execution order of each process such as actions, sequences, steps and stages in the devices, systems, programs and methods shown in the claims, specifications and drawings can be implemented in any order as long as "before", "prior to", etc. are not specifically stated, and the output of the previous process is not used in the subsequent process. Even if the action flow in the claims, specifications and drawings is described using "first," "next," etc. for convenience, it does not mean that it must be implemented in this order.

Claims

1. A management device for managing the charging and discharging of a plurality of storage units connected in series, characterized in that: The management device comprises: an equalizing unit that equalizes the voltages of the plurality of power storage units; and A power transmission and reception unit that (i) transmits the power of the multiple power storage units to an external device different from the load and the charging device, or (ii) receives the power supplied to the multiple power storage units from the external device, without disconnecting or switching the electrical connection between (a) the multiple power storage units and (b-1) a load that uses the power of the multiple power storage units or (b-2) a charging device that charges the multiple power storage units.

2. The management device according to claim 1, characterized in that: The external device includes one or more power storage units, and the one or more power storage units are arranged between (a) the plurality of power storage units and (b-1) the load or between (b-2) the charging device, and are connected in series with the plurality of power storage units.

3. The management device according to claim 1 or 2, characterized in that: The power transmission and reception unit includes a voltage adjustment unit that adjusts a voltage of transmitted or received power to an arbitrary value.

4. The management device according to any one of claims 1 to 3, characterized in that: The power transmission and receiving unit: The power transmission or reception is started according to the received signal for starting the power transmission or reception, or the power transmission or reception is stopped according to the received signal for stopping the power transmission or reception.

5. The management device according to any one of claims 1 to 4, characterized in that: The power transmission and reception unit includes an isolated bidirectional DC-DC converter.

6. The management device according to any one of claims 1 to 5, characterized in that: Also features: a storage unit storing first identification information and second identification information assigned to each of the plurality of storage cells; and an identification information conversion unit, referring to the information stored in the storage unit, converting the first identification information included in the signal received from the outside into the second identification information, and converting the second identification information included in the signal sent to the outside into the first identification information; and the second identification information assigned to each of the plurality of storage cells is different from each other; The first identification information assigned to each of the plurality of storage cells is (i) different from all of the second identification information or (ii) identical to all of the second identification information.

7. A power storage device, characterized in that: have: the plurality of power storage units; and the management device according to any one of claims 1 to 6.

8. A power storage system, characterized in that: have: A plurality of power storage devices according to claim 7; a power line electrically connected to the power transmission and reception sections of the power storage devices so as to enable power to be transmitted between any of the power storage devices; and a control unit that controls the power transmission and reception unit of at least one of the power storage devices; and The plurality of power storage cells of each power storage device are connected in series.

9. The power storage system according to claim 8, characterized in that: The rated voltage of a first power storage device and the rated voltage of a second power storage device constituting the plurality of power storage devices are different from each other.

10. The power storage system according to claim 8, characterized in that: The number of the plurality of power storage cells included in a first power storage device constituting the plurality of power storage devices is different from the number of the plurality of power storage cells included in a second power storage device constituting the plurality of power storage devices.

11. The power storage system according to claim 9 or 10, characterized in that: The power transmission and reception unit of at least one of the first power storage device and the second power storage device includes a bidirectional DC-DC converter.

12. The power storage system according to any one of claims 9 to 11, characterized in that: The first power storage device is a power storage device disposed closest to the negative electrode among the plurality of power storage devices; The positive terminals and negative terminals of the plurality of power storage cells of the first power storage device are physically connected to the power line and are always electrically connected to the power line.

13. The power storage system according to any one of claims 8 to 12, characterized in that: The control unit has: a determination unit that determines, based on the voltage or charge / discharge state of each of the plurality of storage cells of each of the plurality of storage devices, (i) a storage device that transmits power to the power line and (ii) a storage device that receives power from the power line, among the plurality of storage devices; and The command generating unit generates at least one of (i) a command for causing the power transmitting and receiving unit of the power storage device transmitting power to the power line to start power transmitting operation, and (ii) a command for causing the power transmitting and receiving unit of the power storage device receiving power from the power line to start power receiving operation.

14. The power storage system according to claim 13, characterized in that: The determination unit determines at least one of (i) a power storage device to stop the power transmission operation and (ii) a power storage device to stop the power reception operation based on the voltage or charge / discharge state of each of the plurality of power storage cells included in each of the plurality of power storage devices; The command generation unit generates at least one of (i) a command for causing the power transmission and reception unit of the power storage device that stops the power transmission operation to stop the power transmission operation, and (ii) a command for causing the power transmission and reception unit of the power storage device that stops the power reception operation to stop the power reception operation.

15. A power storage system, characterized in that: have: a plurality of electrical storage devices; and a control unit that controls each of the plurality of power storage devices; and The plurality of power storage devices respectively include: A plurality of power storage units connected in series; an equalizing unit for equalizing the voltages of the plurality of power storage units; a storage unit storing first identification information and second identification information assigned to each of the plurality of storage cells; and an identification information conversion unit, referring to the information stored in the storage unit, converting the first identification information included in the signal received from the control unit into the second identification information, and converting the second identification information included in the signal sent to the control unit into the first identification information; The plurality of power storage units of each power storage device are connected in series, the first identification information assigned to each of the plurality of storage cells is different from each other; The first identification information assigned to each of the plurality of storage cells is (i) different from all of the second identification information or (ii) identical to all of the second identification information.

16. The power storage system according to claim 15, characterized in that: In at least one of the plurality of power storage devices, the equalization unit, the storage unit, and the identification information conversion unit are physically arranged in different casings or on physically different substrates.

17. The power storage system according to claim 15 or 16, characterized in that: At least two of the plurality of power storage devices are connected in parallel.

18. The power storage system according to any one of claims 15 to 17, characterized in that: At least two of the plurality of power storage devices are connected in series.

19. An electrical device, characterized in that: have: The power storage system according to any one of claims 8 to 18; and The load utilizes the electric power of the power storage system.

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