Battery power supply device

Abstract

To provide a battery power supply device that facilitates making effective use of a secondary battery.SOLUTION: Each battery block BB includes a serial switching element SS that is connected in series to a secondary battery B connected to first and second terminals T1, T2, and a bypass switching element BS that is connected in parallel to an in-block serial circuit SC to which the secondary battery B and the serial switching element SS are connected in series. Each battery block allows the secondary battery B to be attached to and detached from it, and is connected in series to a parallel circuit of the in-block serial circuit SC the bypass switching element BS. An attachment / detachment control unit 31 can control each battery block BB between an incorporated status in which the bypass switching element BS is turned off and the serial switching element SS is turned on, and a detached status in which the DC switching element SS is turned off and the bypass switching element BS is turned on. Upon receiving a designation of a battery block BB, the designated battery block BB is set to the detached status.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a battery power supply device that uses a battery as a power source.

Background Art

[0002] Conventionally, various electric devices with detachable battery packs have been known, such as electric bicycles, electric tools, electric carrier carts, electric suitcases, electric unicycles, electric lawn mowers, electric tillers, and electric kick scooters (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, electric devices such as electric bicycles and electric tools are not used constantly. Therefore, during the period when the electric device is not in use, secondary batteries such as the battery pack or single battery of the electric device are not utilized.

[0005] An object of the present invention is to provide a battery power supply device that can easily and effectively utilize a secondary battery.

Means for Solving the Problems

[0006] The battery power supply device according to the present invention includes a series battery module in which a plurality of battery blocks are connected in series, a detachment control unit that controls detachment of the battery blocks, and an operation reception unit that receives designation of the battery blocks by a user. Each of the battery blocks includes a first terminal connectable to one electrode of a secondary battery, a second terminal connectable to the other electrode of the secondary battery, a series switching element connected in series to the secondary battery connected to the first and second terminals, and a bypass switching element connected in parallel to a block internal series circuit in which the secondary battery and the series switching element are connected in series. At least one of the plurality of battery blocks is detachable from the secondary battery. In the series battery module, parallel circuits of the block internal series circuit and the bypass switching element in each battery block are connected in series, whereby the plurality of battery blocks are connected in series. The detachment control unit can control each battery block to an inclusion state in which the bypass switching element is turned off and the series switching element is turned on, and a detachment state in which the series switching element is turned off and the bypass switching element is turned on. When a battery block is designated by the operation reception unit, the designated battery block is set to the detachment state.

[0007] According to this configuration, when the user designates, by the operation reception unit, the battery block from which the secondary battery is to be removed, the battery block enters the detachment state, the series switching element is turned off, and the bypass switching element is turned on. As a result, the current flowing through the secondary battery of the designated battery block becomes zero, and the user can remove the secondary battery from the battery block and effectively utilize it for other purposes. On the other hand, since the bypass switching element is turned on, the remaining secondary batteries other than the removed secondary battery remain connected in series. As a result, it is possible to output a voltage obtained by summing the output voltages of the remaining secondary batteries. Thereby, it becomes possible to achieve both high voltage output by the battery power supply device and effective utilization of the secondary batteries.

[0008] Furthermore, it further includes a grounding terminal for grounding, and at least one of the plurality of battery blocks further includes a grounding switching element interposed between either one of the first and second terminals and the grounding terminal. The in-block series circuit of the battery block including the grounding switching element further includes a disconnecting switching element serially connected to the secondary battery on the side opposite to the series switching element. When the detachment control unit receives the designation of the battery block including the grounding switching element by the operation reception unit, it is preferable to turn off the series switching element by setting the designated battery block to the detached state, further turn off the disconnecting switching element, and turn on the grounding switching element.

[0009] According to this configuration, when the user designates the battery block from which the secondary battery is to be removed by the operation reception unit, the battery block becomes detached, the series switching element is turned off, the disconnecting switching element is further turned off, and the grounding switching element is turned on. As a result, the current flowing through the designated secondary battery becomes zero, and the secondary battery becomes in an electrically floating state. In this state, as a result of the grounding switching element being turned on, the secondary battery becomes at the ground potential. In this way, the current flowing through the designated secondary battery becomes zero, and by setting the secondary battery to the ground potential, the safety of the user attempting to remove the secondary battery is improved.

[0010] Also, when the secondary battery is attached to the battery block from which the secondary battery has been removed, it is preferable that the detachment control unit further turns off the grounding switching element and turns on the disconnecting switching element of the battery block to which the secondary battery is attached.

[0011] According to this configuration, the attached secondary battery can be switched between the detached state and the joined state.

[0012] Further, when the secondary battery is attached to the battery block from which the secondary battery has been removed, it is preferable that the attachment / detachment control unit further sets the battery block to which the secondary battery is attached to the joined state.

[0013] According to this configuration, the output voltage of the attached secondary battery is added to the output voltage of the series battery module.

[0014] Further, it is preferable to further include a grounding terminal for grounding, and at least one of the plurality of battery blocks further includes a contact terminal that can contact the housing of the secondary battery and is electrically connected to the grounding terminal.

[0015] According to this configuration, since the housing of the secondary battery becomes the ground potential, the safety of the user who attempts to attach / detach the secondary battery is improved.

[0016] Further, an SOC acquisition unit that acquires the SOC of the secondary battery of each battery block, and when charging the series battery module, the battery blocks among the plurality of battery blocks whose SOC of the secondary battery is less than 100% are grouped into a first group with a relatively large SOC of the secondary battery and a second group with a relatively small SOC of the secondary battery, and the battery blocks in the first group are set to the joined state, and the battery blocks in the second group are set to the detached state, and it is preferable to further include a charge control unit that preferentially charges the battery blocks in the first group.

[0017] According to this configuration, secondary batteries with a relatively large SOC, that is, those that take a short time to be fully charged, are preferentially charged. As a result, each secondary battery is charged so that the number of fully charged secondary batteries increases quickly. When the number of fully charged secondary batteries increases, when the user needs a secondary battery to use an electric device, it becomes easy to remove and use the fully charged secondary battery from the battery power supply device. As a result, the convenience of the user is improved.

[0018] Further, it is preferable that the charge control unit sets the battery block with the highest SOC among the battery blocks whose SOC is less than 100% as the first group.

[0019] According to this configuration, the time until one fully charged secondary battery is increased is minimized.

[0020] Further, it is preferable to further include an SOC acquisition unit that acquires the SOC of the secondary battery of each battery block, and a discharge control unit that sets the battery block including the secondary battery whose SOC indicates full charge to the detached state when discharging the series battery module.

[0021] According to this configuration, since the fully charged secondary battery is not discharged, the number of fully charged secondary batteries is maintained in a state where it is as large as possible. The larger the number of fully charged secondary batteries, the easier it is to remove and use the fully charged secondary battery from the battery power supply device when the user needs a secondary battery to use the electric device. As a result, the convenience for the user is improved.

[0022] Further, it is preferable to further include an SOC acquisition unit that acquires the SOC of the secondary battery of each battery block, and a charge control unit that controls the charging of each battery block by controlling the switching between the joined state and the detached state of each battery block so as to equalize the SOC of the secondary battery of each battery block.

[0023] According to this configuration, by switching between the joined state and the detached state, each secondary battery can be selectively charged, so it is easy to equalize the SOC of each secondary battery.

[0024] Further, in addition to the SOC, the charge control unit preferably controls the charging of each battery block based on at least one of the temperature of the secondary battery of each battery block, the continuous energization time which is the time during which each battery block has been in the joined state continuously retroactively from the current time, and the continuous rest time which is the time during which each battery block has been in the detached state continuously retroactively from the current time.

[0025] When the temperature of the secondary battery is high, it is likely to deteriorate. When the continuous power-on time is long, it is likely to deteriorate. Therefore, by controlling the charging of each battery block based on the temperature of the secondary battery or the continuous power-on time, it becomes easy to reduce the deterioration of the secondary battery. Also, by considering the continuous rest time, the secondary battery can be made into a detached state periodically, and by making it possible to measure the open-circuit terminal voltage, it becomes easy to accurately obtain the SOC of the secondary battery.

[0026] Also, it is preferable to further include an SOC acquisition unit that acquires the SOC of the secondary battery of each battery block, and a discharge control unit that controls the discharge of each battery block by controlling the switching between the joined state and the detached state of each battery block so as to equalize the SOC of the secondary battery of each battery block.

[0027] According to this configuration, by switching between the joined state and the detached state, each secondary battery can be selectively discharged, so it becomes easy to equalize the SOC of each secondary battery.

[0028] Also, in addition to the SOC, the discharge control unit preferably controls the discharge of each battery block based on at least one of the temperature of the secondary battery of each battery block, the continuous power-on time which is the time that each battery block has been in the joined state continuously retroactively from the current time, and the continuous rest time which is the time that each battery block has been in the detached state continuously retroactively from the current time.

[0029] When the temperature of the secondary battery is high, it is likely to deteriorate. When the continuous power-on time is long, it is likely to deteriorate. Therefore, by controlling the discharge of each battery block based on the temperature of the secondary battery or the continuous power-on time, it becomes easy to reduce the deterioration of the secondary battery. Also, by considering the continuous rest time, the secondary battery can be made into a detached state periodically, and by making it possible to measure the open-circuit terminal voltage, it becomes easy to accurately obtain the SOC of the secondary battery.

[0030] Further, it is preferable that at least one of the plurality of battery blocks further includes an inversion circuit for inverting the polarity of the secondary battery.

[0031] According to this configuration, it is possible to connect a part of the plurality of battery blocks connected in series after inverting their polarities. As a result, it becomes easy to increase the degree of freedom of the voltage obtained from the series battery module or to move the charge amount between the battery blocks in the series battery module.

[0032] Further, it is preferable that each of the secondary batteries is a battery pack for electric equipment.

[0033] According to this configuration, by attaching a plurality of battery packs for electric equipment to each battery block, it is possible to obtain the series voltage of the plurality of battery packs, so that it becomes easy to effectively utilize the battery packs.

[0034] Further, it is preferable to further include a plurality of the secondary batteries.

[0035] According to this configuration, the battery power supply device includes a plurality of secondary batteries.

Advantages of the Invention

[0036] The battery power supply device having such a configuration can easily effectively utilize the secondary battery.

Brief Description of the Drawings

[0037]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0038] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In each figure, components denoted by the same reference numerals are the same components, and their descriptions will be omitted.

[0039] (First Embodiment)

[0040] FIG. 1 is a block diagram showing an example of the configuration of a battery power supply device according to the first embodiment of the present invention. The battery power supply device 1 shown in FIG. 1 generally includes a series battery module 2, a control unit 3, and a touch panel display 4 (operation reception unit). The series battery module 2 includes a plurality of battery blocks BB, input / output terminals TT1 and TT2, and a ground terminal TE for grounding. In the example shown in FIG. 1, the series battery module 2 includes N battery blocks BB.

[0041] A plurality of battery blocks BB are connected in series. Each battery block BB is assigned block numbers from 1 to N in order from the high potential side. The battery block BB with block number 1 is described as battery block BB1, the battery block BB with block number 2 is described as battery block BB2, and the battery block BB with block number N is described as battery block BBN.

[0042] The battery block BB includes a first terminal T1 connectable to the + electrode (one electrode) of the secondary battery B, a second terminal T2 connectable to the - electrode (the other electrode) of the secondary battery B, a series switching element SS connected in series to the secondary battery B connected to the first terminal T1 and the second terminal T2, a bypass switching element BS connected in parallel to the in-block series circuit SC in which the secondary battery B and the series switching element SS are connected in series, and a contact terminal CT that can contact the housing BH of the secondary battery B and is electrically connected to the ground terminal TE.

[0043] The series switching element SS and the bypass switching element BS may be semiconductor switching elements such as transistors, or may be mechanical relay switches. The series switching element SS and the bypass switching element BS are turned on and off in response to a control signal from the control unit 3.

[0044] One end of the parallel circuit of the in-block series circuit SC and the bypass switching element BS is P1 and the other end is P2. One end P1 of the battery block BB1 is connected to the input / output terminal TT1, and the other end P2 of the battery block BBN is connected to the input / output terminal TT2. Between the battery blocks BB1 to BBN, the other end P2 of the battery block BB on the high potential side is connected to one end P1 of the battery block BB on the low potential side.

[0045] As a result, in each battery block BB, the parallel circuit of the in-block series circuit SC and the bypass switching element BS is connected in series, whereby a plurality of battery blocks BB are connected in series. The input / output terminals TT1 and TT2 are the input / output terminals of the entire series battery module 2 and the input / output terminals of the battery power supply device 1. When the battery power supply device 1 discharges, the series voltage of the plurality of battery blocks BB is output to the input / output terminals TT1 and TT2, and when the battery power supply device 1 is charged, the charging voltage applied to the input / output terminals TT1 and TT2 is applied to the series circuit of the plurality of battery blocks BB.

[0046] The first terminal T1 and the second terminal T2 are, for example, contact terminals, connectors, etc., and are connectable to the + electrode and - electrode of the secondary battery B. Thereby, the battery block BB is detachable from the secondary battery B. Hereinafter, the secondary battery B of the battery block BB1 may be described as the secondary battery B1, the secondary battery B of the battery block BB2 may be described as the secondary battery B2, and the secondary battery B of the battery block BBN may be described as the secondary battery BN, etc., with block numbers assigned to the secondary batteries B attached to each battery block BB.

[0047] Note that it is not limited to the example where all the battery blocks BB are detachable from the secondary battery B, and at least one of the battery blocks BB1 to BBN may be detachable from the secondary battery B. The first terminal T1 and the second terminal T2 only need to be connectable to the secondary battery B, and in the battery blocks BB1 to BBN, there may be a mixture of battery blocks BB having connection terminals for fixedly connecting the secondary battery B as the first terminal T1 and the second terminal T2.

[0048] The secondary battery B may be, for example, a battery pack of a secondary battery used in various electric devices such as electric bicycles, electric tools, electric carrier carts, electric suitcases, electric unicycles, electric lawn mowers, electric tillers, and electric kick scooters. Also, the plurality of secondary batteries B may contain a mixture of battery packs of different electric devices. Also, the plurality of secondary batteries B may contain single cells of the secondary battery.

[0049] The secondary battery B has a housing BH. The housing BH is the outer shell portion of the secondary battery B that is insulated from the + electrode, - electrode, signal terminals, etc. of the secondary battery B.

[0050] The contact terminal CT is a conductive contact member such as a leaf spring, coil spring, and electrode plate. When the secondary battery B is attached to the battery block BB, the contact terminal CT comes into contact with the housing BH. Since the contact terminal CT is electrically connected to the ground terminal TE, when the secondary battery B is attached to the battery block BB, the housing BH of the secondary battery B is grounded via the contact terminal CT and the ground terminal TE. As a result, the secondary battery B2 is set to the ground potential, improving the safety of the user who attempts to detach the secondary battery B from the battery block BB.

[0051] Note that the example is not limited to all battery blocks BB having the contact terminal CT, and a configuration in which at least one of the plurality of battery blocks has the contact terminal CT may be used. Alternatively, not all battery blocks BB need to have the contact terminal CT, and the battery power supply device 1 does not need to have the ground terminal TE.

[0052] The touch panel display 4 corresponds to an example of an operation reception unit. The touch panel display 4 receives at least an operation input from a user who designates any one of the battery blocks BB1 to BBN. Further, the touch panel display 4 displays information in response to a control signal from the control unit 3. Note that the operation reception unit is not limited to the touch panel display, and may be various operation input devices such as a push button switch.

[0053] The control unit 3 is configured using, for example, a CPU (Central Processing Unit) that performs predetermined arithmetic processing, a RAM (Random Access Memory) that temporarily stores data, a non-volatile storage device such as a flash memory, and peripheral circuits thereof. Then, the control unit 3 functions as a detachment control unit 31, an SOC acquisition unit 32, a charge control unit 33, and a discharge control unit 34 by executing, for example, a program stored in the above-described storage device.

[0054] The attachment / detachment control unit 31 can control each battery block BB between an attached state in which the bypass switching element BS is turned off and the series switching element SS is turned on, and a detached state in which the series switching element SS is turned off and the bypass switching element BS is turned on. In the example shown in FIG. 1, the case where the battery blocks BB1, BB3, BBN are in the attached state and the battery block BB2 is in the detached state is illustrated.

[0055] When the attachment / detachment control unit 31 receives the designation of the battery block BB via the touch panel display 4, the designated battery block BB is set to the detached state. Further, when a secondary battery B is attached to a battery block BB from which the secondary battery B has been removed, the attachment / detachment control unit 31 sets the battery block BB to which the secondary battery B is attached to the attached state.

[0056] The presence or absence of attachment of the secondary battery B in each battery block BB may be detected, for example, by providing a detection unit such as a sensor or a switch in the battery power supply device 1 for detecting the presence or absence of the secondary battery B, or the user may operate the touch panel display 4 to input the presence or absence of attachment of the secondary battery B in each battery block BB. The attachment / detachment control unit 31 can acquire the presence or absence of attachment of the secondary battery B in each battery block BB based on the information obtained by these detection units and the touch panel display 4.

[0057] FIG. 2 is a flowchart showing an example of the attachment / detachment control process by the attachment / detachment control unit 31 shown in FIG. 1. Hereinafter, the same steps are assigned the same step numbers and the description thereof is omitted.

[0058] For example, when secondary batteries B are attached to all of the battery blocks BB1 to BBN and all of the battery blocks BB1 to BBN are in the attached state, a voltage obtained by summing the output voltages of the secondary batteries B1 to BN is output to the input / output terminals TT1, TT2. Thereby, the battery power supply device 1 can easily output a high voltage by effectively utilizing the secondary batteries B used for various electric devices.

[0059] Then, the attachment / detachment control unit 31 checks whether the battery block BB has been specified by the touch panel display 4 (step S1). If the battery block BB has been specified by the touch panel display 4 (YES in step S1), the attachment / detachment control unit 31 sets the specified battery block BB to the detached state (step S2), and transfers the process back to step S1.

[0060] Accordingly, when the user wants to use, for example, an electric bicycle, the user operates the touch panel display 4 to input, for example, "2" as the block number of the battery block BB to which the secondary battery B for the electric bicycle is attached. Then, as shown in FIG. 1, the attachment / detachment control unit 31 turns off the series switching element SS of the specified battery block BB2 and turns on the bypass switching element BS to set it to the detached state (step S2).

[0061] The secondary battery B2 for which the series switching element SS has been turned off is excluded from the current path flowing through the series battery module 2, and the secondary battery B2 can be removed from the battery block BB2. On the other hand, when the bypass switching element BS of the battery block BB2 is turned on, the secondary batteries B1, B3 to BN excluding the secondary battery B2 remain in series connection. As a result, the voltage obtained by summing the output voltages of the secondary batteries B1, B3 to BN is output to the input / output terminals TT1, TT2. Thus, it is possible to output a high voltage while allowing the user to remove the desired secondary battery B from the battery power supply device 1. Thereby, it is possible to achieve both high voltage output by the battery power supply device 1 and effective utilization of the secondary batteries B1 to BN.

[0062] On the other hand, if the battery block BB has not been specified (NO in step S1), the attachment / detachment control unit 31 checks whether the secondary battery B has been attached to the battery block BB from which the secondary battery B has been removed (step S3). If there is no attachment of the secondary battery B (NO in step S3), the attachment / detachment control unit 31 transfers the process back to step S1.

[0063] On the other hand, when the secondary battery B is attached to the battery block BB from which the secondary battery B has been removed (YES in step S3), the detachment control unit 31 turns off the bypass switching element BS of the battery block BB to which the secondary battery B is attached and turns on the series switching element SS to bring it into an active state (step S4), and the process returns to step S1 again.

[0064] Thereby, after the user finishes using an electric device such as an electric bicycle, by attaching the secondary battery B of the unused electric device to the series battery module 2, the secondary battery B is connected in series with other secondary batteries B, and the output voltage of the newly attached secondary battery B is added to the output voltages of the input / output terminals TT1 and TT2. Thereby, it becomes possible to effectively utilize the secondary battery B of the unused electric device. Also, as will be described later, it is also possible to charge the secondary battery B attached to the series battery module 2.

[0065] The SOC acquisition unit 32 acquires the SOC (State Of Charge) of the secondary battery B in each battery block BB. Specifically, for example, an open-circuit voltage - SOC characteristic table showing the relationship between the open-circuit voltage and the SOC of the secondary batteries B1 to BN is stored in advance in the above-described storage device, and the battery power supply device 1 may include a schematic voltage detection unit that detects the terminal voltages of the secondary batteries B1 to BN respectively.

[0066] Then, the SOC acquisition unit 32 may acquire the terminal voltage, that is, the open-circuit voltage, detected by the voltage detection unit from the secondary battery B of the battery block BB in the detached state, that is, the state where the series switching element SS is off and the bypass switching element BS is on, and acquire the SOC associated with the open-circuit voltage by the open-circuit voltage - SOC characteristic table as the SOC of the secondary battery B.

[0067] Also, for example, the full charge capacities of the secondary batteries B1 to BN are stored in advance in the above-described storage device, and the battery power supply device 1 may include a schematic current detection unit that detects the current flowing through the series battery module 2.

[0068] Then, the SOC acquisition unit 32, for example, takes the battery block BB in the connected state, that is, the secondary battery B of the battery block BB where the bypass switching element BS is off and the series switching element SS is on, as the processing target, and integrates the current value detected by the current detection unit, with the current value in the charging direction being positive and the current value in the discharging direction being negative. And the SOC acquisition unit 32 may calculate the SOC of the secondary battery B to be processed from the ratio of the charge amount obtained by integrating the current value to the full charge capacity of the secondary battery B to be processed.

[0069] When charging the series battery module 2, the charge control unit 33 groups the battery blocks BB among the plurality of battery blocks BB1 to BBN whose SOC is less than 100% into a first group G1 with a relatively large SOC of the secondary battery B and a second group G2 with a small SOC of the secondary battery B. Then, the charge control unit 33 sets the battery blocks BB in the first group G1 with a large SOC to the connected state and the battery blocks BB in the second group G2 with a small SOC to the disconnected state, thereby preferentially charging the secondary battery B of the battery blocks BB in the first group G1 with a large SOC.

[0070] The number of battery blocks BB grouped into the first group G1 may be one, and the number of battery blocks BB grouped into the second group G2 may also be one.

[0071] FIG. 3 is a flowchart showing an example of the charge control process by the charge control unit 33 shown in FIG. 1. When charging the series battery module 2, for example, the user may connect a charging device (not shown) to the input / output terminals TT1 and TT2, or for example, the charge control unit 33 may connect a charging device (not shown) to the input / output terminals TT1 and TT2 by the user operating the touch panel display 4 to instruct charging.

[0072] For example, when the battery power supply device 1 is attached to an electric vehicle and used, the charging stand corresponds to the charging device, and the charging voltage supplied from the charging stand to the electric vehicle is applied to the input / output terminals TT1 and TT2.

[0073] The charge control unit 33 may start the charge control process, for example, by an input operation on the touch panel display 4 by the user, may automatically detect that a charging device is connected to the input / output terminals TT1 and TT2 and start the charge control process, or may start the charge control process in response to a control signal from the outside.

[0074] First, the SOC acquisition unit 32 acquires the SOCs of the secondary batteries B1 to BN (step S11). For the sake of convenience of explanation, step S11 is described as one step of the charge control process. However, the SOC acquisition process by the SOC acquisition unit 32 is constantly executed in parallel with charging and discharging, and the SOCs of the secondary batteries B1 to BN are constantly updated.

[0075] Next, the charge control unit 33 groups the plurality of battery blocks BB1 to BBN into a group A in which the SOC of the secondary battery B is 100% and a group G in which the SOC of the secondary battery B is less than 100% (step S12).

[0076] Next, the charge control unit 33 groups the battery blocks BB in group G with an SOC less than 100% into a first group G1 with a relatively larger SOC of the secondary battery B and a second group G2 with a relatively smaller SOC of the secondary battery B (step S13).

[0077] For example, the charge control unit 33 may set a predetermined number of battery blocks BB in descending order of SOC among the battery blocks BB in group G as the first group G1, and the remaining battery blocks BB as the second group G2. The set number can be appropriately set, for example, by the user operating the touch panel display 4. Also, the set number may be 1. In this case, among the battery blocks BB in group G, only the battery block BB with the largest SOC becomes the first group G1.

[0078] Next, the charge control unit 33 charges the battery blocks BB of the first group G1 by setting the battery blocks BB of the first group G1 to the joined state and the battery blocks BB of the second group G2 and group A to the detached state (step S14).

[0079] By steps S11 to S14, the secondary batteries B with relatively large SOC, that is, the secondary batteries B with a short time until full charge, are preferentially charged. As a result, the secondary batteries B1 to BN are charged so that the number of fully charged secondary batteries B increases quickly. When the number of fully charged secondary batteries B increases, when the user needs a secondary battery B to use an electric device, it becomes easy to remove and use the fully charged secondary battery B from the battery power supply device 1. As a result, the convenience for the user is improved.

[0080] Thereafter, during the period when charging by the charging device continues, steps S11 to S14 are repeated, and the secondary batteries B1 to BN are sequentially charged.

[0081] When discharging the series battery module 2, the discharge control unit 34 sets the battery blocks BB including the secondary batteries B indicating full charge to the detached state.

[0082] FIG. 4 is a flowchart showing an example of the discharge control process by the discharge control unit 34 shown in FIG. 1. When discharging the series battery module 2, for example, the user may connect a load device (not shown) to the input / output terminals TT1 and TT2. For example, when the user operates the touch panel display 4 to instruct discharge, the charge control unit 33 may connect the load device (not shown) to the input / output terminals TT1 and TT2.

[0083] For example, when the battery power supply device 1 is attached to an electric vehicle and used, the drive motor of the electric vehicle etc. corresponds to the load device, and the input / output terminals TT1 and TT2 may be connected to the load device by the control on the electric vehicle side.

[0084] The discharge control unit 34 may start the discharge control process, for example, by an input operation on the touch panel display 4 by the user, may automatically detect that a load device is connected to the input / output terminals TT1 and TT2 and start the discharge control process, or may start the discharge control process in response to a control signal from the outside.

[0085] First, the SOCs of the secondary batteries B1 to BN are acquired by the same step S11 as described above. Next, by the discharge control unit 34 executing the same step S12 as described above, the battery blocks BB1 to BBN are grouped into a group A with an SOC of 100% and a group G with an SOC of less than 100%.

[0086] The charge control unit 33 and the discharge control unit 34 may be integrally configured, and step S12 may be executed by the charge control unit 33 or may be executed by the discharge control unit 34.

[0087] Next, the discharge control unit 34 discharges the battery blocks BB of group G by setting the battery blocks BB of group G to the joined state and the battery blocks BB of group A to the detached state (step S21). Thereafter, while the discharge of the series battery module 2 continues, steps S11 to S21 are repeated, and the battery blocks BB of group G are discharged.

[0088] According to the processing of steps S11 to S21, the fully charged secondary batteries B are not discharged, so the number of fully charged secondary batteries B is maintained in a state where it is as large as possible. The larger the number of fully charged secondary batteries B, the easier it is to remove and use the fully charged secondary batteries B from the battery power supply device 1 when the user needs the secondary batteries B to use the electric equipment. As a result, the convenience of the user is improved.

[0089] Note that in step S21, the discharge control unit 34 only needs to set the battery block BB of group A to the detached state, and it is not necessarily required to set all the battery blocks BB of group G to the joined state. The discharge control unit 34 may select a battery block BB from group G to set it to the joined state so that a desired voltage can be obtained between the input / output terminals TT1 and TT2, and set the remaining battery blocks BB to the detached state.

[0090] Note that the battery power supply device 1 does not necessarily need to include the discharge control unit 34, nor does it necessarily need to include the charge control unit 33 or the SOC acquisition unit 32.

[0091] FIG. 5 is a conceptual circuit diagram showing a modified example of the series battery module 2. The series battery module 2a shown in FIG. 5 includes a battery block BBa instead of the battery block BB. The battery block BBa shown in FIG. 5 further includes an inversion circuit RC for inverting the polarity of the secondary battery B in addition to the battery block BB. The inversion circuit RC is configured using, for example, a series circuit of inversion switching elements SR1 and SR2.

[0092] One end of the inversion switching element SR1 is connected to the other end P2, and the other end of the inversion switching element SR1 is connected to one end of the inversion switching element SR2. The other end of the inversion switching element SR2 is connected to the connection point between the first terminal T1 and the series switching element SS.

[0093] The connection point P3 between the inversion switching element SR1 and the inversion switching element SR2 is connected to one end P1 of another battery block BBa adjacent to the lower potential side than its own block. One end P1 and the connection point P3 serve as the input / output terminals of each battery block BBa.

[0094] In the battery block BBa, a parallel circuit of the in-block series circuit SC and the bypass switching element BS in each battery block BB is connected in series via the inversion switching element SR1, whereby a plurality of battery blocks BBa are connected in series.

[0095] The inversion switching elements SR1 and SR2 may be semiconductor switching elements such as transistors, or may be mechanical relay switches. The inversion switching elements SR1 and SR2 turn on and off in response to a control signal from the control unit 3.

[0096] In addition to the above-described connected state and disconnected state, the battery block BBa can be set to an inverted state in which the polarity of the secondary battery B is inverted by the inversion circuit RC. In the example shown in FIG. 5, the battery block BB1a shows the connected state, the battery block BB2a shows the disconnected state, and the battery block BB3a shows the inverted state.

[0097] When the battery block BBa is used, in the connected state, the series switching element SS and the inversion switching element SR1 are on, and the bypass switching element BS and the inversion switching element SR2 are off. In the disconnected state, the bypass switching element BS and the inversion switching element SR1 are on, and the series switching element SS and the inversion switching element SR2 are off. In the inverted state, the bypass switching element BS and the inversion switching element SR2 are on, and the series switching element SS and the inversion switching element SR1 are off. Note that in the disconnected state, the bypass switching element BS and the inversion switching element SR1 may be off and the series switching element SS and the inversion switching element SR2 may be on.

[0098] That is, when the battery block BBa is used, in steps S2, S4, S14, S21, and steps S37, S44, S2b, S4b described later, the inversion switching elements SR1 and SR2 in the connected state and the disconnected state may be turned on and off as described above.

[0099] Further, the output voltage between the input / output terminals TT1 and TT2, that is, the output voltage of the series battery module 2a, is a voltage obtained by subtracting the output voltage of the battery block BBa in the inverted state from the sum of the output voltages of the battery blocks BBa in the joined state. Therefore, when using the series battery module 2a, in step S21, the discharge control unit 34 controls the battery blocks BBa of group G to be in three states: the joined state, the inverted state, and the detached state, thereby increasing the degree of freedom in controlling the output voltage of the series battery module 2a.

[0100] Note that in the battery power supply device 1, at least one of the plurality of battery blocks may be provided with the inversion circuit RC, and the series battery module may be one in which the battery blocks BB and BBa are mixed and connected in series.

[0101] (Second Embodiment)

[0102] Next, the battery power supply device 1a according to the second embodiment of the present invention will be described. FIG. 6 is a block diagram showing an example of the configuration of the battery power supply device 1a according to the second embodiment of the present invention. The battery power supply device 1a is different from the battery power supply device 1 in that it includes a temperature sensor (not shown) for measuring the temperatures T(1) to T(N) of the secondary batteries B1 to BN, and the control unit 3a.

[0103] The control unit 3a is different from the control unit 3 in that it further functions as a temperature acquisition unit 35, a continuous energization time acquisition unit 36, and a continuous rest time acquisition unit 37, and the operations of the charge control unit 33a and the discharge control unit 34a are different.

[0104] Since the other configurations are the same as those of the battery power supply device 1, the description thereof will be omitted, and the characteristic points of the present embodiment will be described below.

[0105] The temperature acquisition unit 35 acquires the temperatures T(1) to T(N) measured by the temperature sensors of the respective battery blocks BB. Hereinafter, the temperatures T(1) to T(N) are collectively referred to as the temperature T.

[0106] The continuous energization time acquisition unit 36 acquires the continuous energization times Pc(1) to Pc(N) of the battery blocks BB1 to BBN. Hereinafter, the continuous energization times Pc(1) to Pc(N) are collectively referred to as the continuous energization time Pc.

[0107] The continuous energization times Pc(1) to Pc(N) are the times during which the battery blocks BB1 to BBN have been in the joined state continuously retrogressing from the current time with the current time as a reference. The continuous energization time acquisition unit 36 can acquire the continuous energization times Pc(1) to Pc(N) by respectively measuring the times during which the battery blocks BB1 to BBN have been continuously in the joined state.

[0108] The continuous rest time acquisition unit 37 acquires the continuous rest times Pd(1) to Pd(N) of the battery blocks BB1 to BBN. Hereinafter, the continuous rest times Pd(1) to Pd(N) are collectively referred to as the continuous rest time Pd.

[0109] The continuous rest times Pd(1) to Pd(N) are the times during which the battery blocks BB1 to BBN have been in the detached state continuously retrogressing from the current time with the current time as a reference. The continuous rest time acquisition unit 37 can acquire the continuous rest times Pd(1) to Pd(N) by respectively measuring the times during which the battery blocks BB1 to BBN have been continuously in the detached state.

[0110] The charge control unit 33a controls the charging of each battery block BB by controlling the switching between the joined state and the detached state of each battery block BB so as to equalize the SOC of the secondary battery B of each battery block BB.

[0111] The discharge control unit 34a controls the discharging of each battery block BB by controlling the switching between the joined state and the detached state of each battery block BB so as to equalize the SOC of the secondary battery B of each battery block BB.

[0112] FIG. 7 is a flowchart showing an example of the charging control process by the charging control unit 33a shown in FIG. 6. The charging process can start in the same manner as in the case of the charging control unit 33. First, the SOC(1) to SOC(N) of each secondary battery B1 to BN are acquired by the same step S11 as described above.

[0113] The SOC of the secondary battery B1 is denoted as SOC(1), the SOC of the secondary battery B2 is denoted as SOC(2), and the SOC of the secondary battery BN is denoted as SOC(N), with the corresponding block numbers described in parentheses. Similarly, for the temperature T, the continuous energization time Pc, and the continuous rest time Pd, the corresponding battery blocks BB and the block numbers of the secondary batteries B are shown in parentheses.

[0114] Next, the temperature acquisition unit 35 acquires the temperatures T(1) to T(N) of each secondary battery B1 to BN (step S31). Step S31 is always executed in parallel with other processes.

[0115] Next, the continuous energization time acquisition unit 36 acquires the continuous energization times Pc(1) to Pc(N) of the battery blocks BB1 to BBN (step S32). Step S32 is always executed in parallel with other processes.

[0116] Next, the continuous rest time acquisition unit 37 acquires the continuous rest times Pd(1) to Pd(N) of the battery blocks BB1 to BBN (step S33). When the continuous rest time Pd exceeds a preset upper limit time, for example, 60 seconds, the continuous rest time acquisition unit 37 initializes the continuous rest time Pd to zero. Step S33 is always executed in parallel with other processes.

[0117] Next, the charging control unit 33a calculates the charging indicators Cc(1) to Cc(N) of the battery blocks BB1 to BBN based on SOC(1) to SOC(N), temperature T(1) to T(N), continuous energization time Pc(1) to Pc(N), and continuous rest time Pd(1) to Pd(N) (step S34). Hereinafter, the charging indicators Cc(1) to Cc(N) are collectively referred to as the charging indicator Cc.

[0118] Assuming the block number is i, the charging index Cc(i) of the battery block BBi is represented by the following formula (1).

[0119] Charging index Cc(i) = KsSOC(i) + KtT(i) + KcPc(i) + KdPd(i) ···(1)

[0120] However, SOC(i) is the SOC of the secondary battery Bi, T(i) is the temperature of the secondary battery Bi, Pc(i) is the continuous energization time of the battery block BBi, and Pd(i) is the continuous rest time of the battery block BBi. Also, Ks is the coefficient of SOC, Kt is the coefficient of temperature T, Kc is the coefficient of the continuous energization time Pc, and Kd is the coefficient of the continuous rest time Pd.

[0121] The coefficients Ks, Kt, Kc, and Kd can be, for example, Ks = Ds / Ns, Kt = Dt / Nt, Kc = Dc / Nc, and Kd = Dd / Nd. Ns, Nt, Nc, and Nd are normalization numbers, and standard values of SOC, temperature T, continuous energization time Pc, and continuous rest time Pd can be used.

[0122] For example, corresponding to 0 to 100% of SOC, Ns can be a value from 0 to 100. Corresponding to -10°C to 50°C of temperature T, Nt can be -10 to 50. For the continuous energization time Pc and the continuous rest time Pd, depending on the time data processing method inside the charge control unit 33a, for example, when internal processing is performed with 1 msec as "1" and 1 sec as "1000", Nc and Nd can be set to 1000.

[0123] Ds, Dt, Dc, and Dd are weighting numbers. By increasing the weighting number of the item for which a greater impact is desired and decreasing the weighting number of the item for which a smaller impact is desired for each item of SOC, temperature T, continuous energization time Pc, and continuous rest time Pd, the charging index Cc can be made an index in which SOC, temperature T, continuous energization time Pc, and continuous rest time Pd are reflected in a well-balanced manner.

[0124] The coefficients Ks, Kt, Kc, Kd, the weighting factors Ds, Dt, Dc, Dd, and the normalization factors Ns, Nt, Nc, Nd may be appropriately set experimentally, for example.

[0125] Next, the charge control unit 33a groups the plurality of battery blocks BB1 to BBN into a group A that cannot be charged when the SOC of the secondary battery B is 100% and a group G that can be charged when the SOC of the secondary battery B is less than 100% (step S35).

[0126] Next, the charge control unit 33a groups the battery blocks BB in group G with an SOC less than 100% into a first group G1 with a relatively small charge index Cc and a second group G2 with a relatively large charge index Cc (step S36). Specifically, the charge control unit 33a may set a predetermined number of battery blocks BB in ascending order of the charge index Cc among the battery blocks BB in group G as the first group G1, and the remaining battery blocks BB as the second group G2. The set number can be appropriately set as described above. When the set number is 1, the charge control unit 33a may set only the battery block BB with the smallest charge index Cc among the battery blocks BB in group G as the first group G1.

[0127] Next, the charge control unit 33a charges the battery blocks BB in the first group G1 by setting the battery blocks BB in the first group G1 to the joined state and the battery blocks BB in the second group G2 and group A to the detached state (step S37).

[0128] As described above, by steps S34 to S37, the charge control unit 33a can control the charging of each battery block BB based on the temperature T(1) to T(N), the continuous energization time Pc(1) to Pc(N), and the continuous rest time Pd(1) to Pd(N) in addition to the SOC.

[0129] Since the charging index Cc includes the term of KsSOC, it becomes larger as the SOC is larger and smaller as the SOC is smaller. Therefore, in step S37, charging the battery block BB of the first group G1 with a relatively small charging index Cc in the connected state basically means charging the battery block BB with a relatively small SOC.

[0130] Therefore, according to steps S34 to S37, the charging control unit 33a can control the charging of each battery block BB by controlling the switching between the connected state and the disconnected state of each battery block BB so as to equalize the SOC of the secondary battery B in each battery block BB.

[0131] Furthermore, since the charging index Cc includes the term of +KtT, it becomes larger as the temperature T is higher and smaller as the temperature T is lower. Therefore, by charging the battery block BB with a relatively small charging index Cc, in addition to the above-mentioned SOC, the battery block BB with a relatively low temperature T is more likely to be charged. The secondary battery B with a high temperature T is likely to deteriorate, and the secondary battery B with a low temperature T is less likely to deteriorate.

[0132] Therefore, according to steps S34 to S37, the charging control unit 33a can preferentially charge the secondary battery B that is relatively less likely to deteriorate while equalizing the SOC of the secondary battery B in each battery block BB, so it is easy to reduce the deterioration of each secondary battery B.

[0133] Furthermore, since the charging index Cc includes the term of +KcPc, it becomes larger as the continuous energization time Pc is longer and smaller as the continuous energization time Pc is shorter. Therefore, by charging the battery block BB with a relatively small charging index Cc, in addition to the above-mentioned SOC, the battery block BB with a relatively short continuous energization time Pc is more likely to be charged.

[0134] A secondary battery B with a long continuous power-on time Pc is prone to deterioration, while a secondary battery B with a short continuous power-on time Pc is less likely to deteriorate. Therefore, according to steps S34 to S37, the charge control unit 33a can preferentially charge the secondary battery B that is relatively less likely to deteriorate while equalizing the SOC of the secondary batteries B in each battery block BB, making it easier to reduce the deterioration of each secondary battery B.

[0135] As described above, the SOC acquisition unit 32 can use a method of acquiring the SOC of the secondary battery B from the terminal voltage of the secondary battery B in the detached state, that is, the open-circuit voltage, and a method of indirectly acquiring the SOC of the secondary battery B by integrating the charge and discharge current. The SOC directly obtained from the open-circuit voltage is more accurate than the SOC indirectly obtained by integrating the charge and discharge current.

[0136] According to the KdPd(i) term of the charge index Cc(i) shown in Equation (1), for the battery block BB in the detached state where the SOC can be directly obtained from the open-circuit voltage, the longer the continuous rest time Pd during which the detached state continues, the larger the charge index Cc(i), and thus the more difficult it is to be charged. And when the continuous rest time Pd exceeds the above upper limit time, the continuous rest time Pd becomes zero, and it becomes easier to be charged.

[0137] Therefore, if there is no influence from terms other than KdPd(i) of the charge index Cc(i), among the battery blocks BB1 to BBN, the battery block BB in the detached state from which a highly accurate SOC can be directly obtained from the open-circuit voltage will be rotated. As a result, by including the term of KdPd(i) in the charge index Cc(i), the acquisition accuracy of SOC(1) to SOC(N) by the SOC acquisition unit 32 will be improved.

[0138] Therefore, by appropriately setting the coefficients Ks, Kt, Kc, and Kd, it becomes easy to improve the accuracy of SOC(1) to SOC(N) while balancing the terms other than KdPd(i) and the term of KdPd(i).

[0139] Note that the battery power supply device 1a does not include a temperature acquisition unit 35, a continuous energization time acquisition unit 36, and a continuous rest time acquisition unit 37, and does not have to execute steps S31 to S33. And the charge index Cc(i) may not include the terms of KtT(i), KcPc(i), and KdPd(i), and the SOC(i) may be directly used as the charge index Cc(i). When the SOC(i) is directly used as the charge index Cc(i), the charge control unit 33a controls the switching between the joining state and the leaving state of each battery block BB so as to equalize the SOC of each secondary battery B without being affected by parameters other than the SOC, thereby controlling the charging of each battery block BB.

[0140] Also, the battery power supply device 1a does not include the temperature acquisition unit 35 and does not execute step S31, and the charge index Cc(i) may not include the term of KtT(i). Alternatively, the battery power supply device 1a does not include the continuous energization time acquisition unit 36 and does not execute step S32, and the charge index Cc(i) may not include the term of KtT(i). Alternatively, the battery power supply device 1a does not include the continuous rest time acquisition unit 37 and does not execute step S33, and the charge index Cc(i) may not include the term of KdPd(i).

[0141] FIG. 8 is a flowchart showing an example of the discharge control process by the discharge control unit 34a shown in FIG. 6. The discharge process can start in the same manner as in the case of the discharge control unit 34. First, SOC(1) to SOC(N) are acquired in step S11 similar to the above, temperature T(1) to T(N) are acquired in step S31, continuous energization time Pc(1) to Pc(N) are acquired in step S32, and continuous rest time Pd(1) to Pd(N) are acquired in step S33.

[0142] Next, the charge control unit 33a calculates the discharge indexes Cd(1) to Cd(N) of the battery blocks BB1 to BBN based on SOC(1) to SOC(N), temperature T(1) to T(N), continuous energization time Pc(1) to Pc(N), and continuous rest time Pd(1) to Pd(N) (step S41). Hereinafter, the discharge indexes Cd(1) to Cd(N) are collectively referred to as the discharge index Cd.

[0143] Assuming the block number is i, the discharge index Cd(i) of the battery block BBi is expressed by the following formula (2).

[0144] Discharge index Cd(i) = Ks(100 - SOC(i)) + KtT(i) + KcPc(i) + KdPd(i) ···(2)

[0145] Formula (2) is different in that the term KsSOC(i) in formula (1) is taken as Ks(100 - SOC(i)). That is, contrary to the charge index Cc(i), the discharge index Cd(i) is an index such that the larger the SOC, the smaller it is, and the smaller the SOC, the larger it is.

[0146] Next, the discharge control unit 34a groups the battery blocks BB1 to BBN into a group A that cannot be discharged with the SOC of the secondary battery B being 0%, and a group G that can be discharged with the SOC of the secondary battery B exceeding 0% (step S42).

[0147] Next, the discharge control unit 34a divides the battery blocks BB in group G with SOC exceeding 0% into

[0148] a first group G1 with a relatively small discharge index Cd and a second group G2 with a relatively large discharge index Cd (step S43). Specifically, the discharge control unit 34a may set a predetermined number of battery blocks BB in ascending order of the small discharge index Cd among the battery blocks BB in group G as the first group G1, and the remaining battery blocks BB as the second group G2. The set number can be set as appropriate as described above. Taking the set number as 1, the discharge control unit 34a may set only the battery block BB with the smallest charge index Cc among the battery blocks BB in group G as the first group G1.

[0149] Next, the discharge control unit 34a discharges the battery blocks BB in the first group G1 by setting the battery blocks BB in the first group G1 to the joined state and the battery blocks BB in the second group G2 and group A to the detached state (step S44).

[0150] As described above, through steps S41 to S44, the discharge control unit 34a can control the discharge of each battery block BB based on the temperature T(1) to T(N), the continuous energization time Pc(1) to Pc(N), and the continuous rest time Pd(1) to Pd(N) in addition to the SOC.

[0151] Since the discharge index Cd includes the term Ks(100 - SOC(i)), the larger the SOC, the smaller the discharge index Cd, and the smaller the SOC, the larger the discharge index Cd. Therefore, discharging the battery block BB with a relatively small discharge index Cd in step S44 basically means discharging the battery block BB with a relatively large SOC.

[0152] Therefore, according to steps S41 to S44, the discharge control unit 34a can control the discharge of each battery block BB by controlling the switching between the connected state and the disconnected state of each battery block BB so as to equalize the SOC of the secondary battery B in each battery block BB.

[0153] The effect of including +KtT(i), +KcPc(i), and +KdPd(i) in the discharge index Cd(i) is the same as that of the above-described charge index Cc(i), so the description thereof is omitted.

[0154] Note that in step S44, the discharge control unit 34a only needs to set the battery blocks BB in the second group G2 and the group A to the disconnected state, and it is not necessarily required to set all the battery blocks BB in the first group G1 to the connected state. The discharge control unit 34a may select a battery block BB from the first group G1 to set it to the connected state and set the remaining battery blocks BB to the disconnected state so as to obtain a desired voltage between the input / output terminals TT1 and TT2.

[0155] Further, the battery power supply device 1a does not include a temperature acquisition unit 35, a continuous energization time acquisition unit 36, and a continuous rest time acquisition unit 37, and does not need to execute steps S31 to S33. And the discharge index Cd(i) does not include the terms of KtT(i), KcPc(i), and KdPd(i), and the SOC(i) may be directly used as the discharge index Cd(i). When the SOC(i) is directly used as the discharge index Cd(i), the discharge control unit 34a controls the switching between the joining state and the leaving state of each battery block BB so as to equalize the SOC of each secondary battery B without being affected by parameters other than the SOC, thereby controlling the discharge of each battery block BB.

[0156] Further, the battery power supply device 1a does not include the temperature acquisition unit 35 and does not execute step S31, and the discharge index Cd(i) may not include the term of KtT(i). Alternatively, the battery power supply device 1a does not include the continuous energization time acquisition unit 36 and does not execute step S32, and the discharge index Cd(i) may not include the term of KtT(i). Alternatively, the battery power supply device 1a does not include the continuous rest time acquisition unit 37 and does not execute step S33, and the discharge index Cd(i) may not include the term of KdPd(i).

[0157] Further, the battery power supply device 1a may include a series battery module 2a instead of the series battery module 2 and use a battery block BBa instead of the battery block BB. When charging the series battery module 2a, when the battery block BBa in the joining state is being charged, the battery block BBa in the inverted state is discharged. That is, within the series battery module 2a, the charge amount can be transferred from the battery block BBa in the inverted state to the battery block BBa in the joining state.

[0158] Therefore, when using the series battery module 2a, the charge control unit 33a may reverse the battery blocks BBa of the second group G2 and the group A in step S37. If the battery blocks BBa of the second group G2 and the group A are reversed, the charge amount moves from the battery blocks BBa of the second group G2 and the group A with a large SOC to the battery blocks BBa of the first group G1 with a small SOC. As a result, it becomes possible to more quickly equalize the SOCs of the secondary batteries B.

[0159] Also, when using the series battery module 2a, the discharge control unit 34a may reverse at least one of the battery blocks BBa of the second group G2 and the group A in step S44. In this way, it becomes possible to discharge at least one of the battery blocks BBa of the first group G1 with a large SOC while charging at least one of the battery blocks BBa of the second group G2 and the group A with a small SOC. As a result, it becomes possible to more quickly equalize the SOCs of the secondary batteries B.

[0160] Note that also in the battery power supply device 1a, similar to the case of the battery power supply device 1, the series battery module may be one in which the battery blocks BB and the battery blocks BBa are mixed and connected in series.

[0161] (Third Embodiment)

[0162] Next, the battery power supply device 1b according to the third embodiment of the present invention will be described. FIG. 9 is a block diagram showing an example of the configuration of the battery power supply device 1b according to the third embodiment of the present invention. The battery power supply device 1b differs from the battery power supply device 1 in that it further includes a ground terminal TE, includes a series battery module 2b instead of the series battery module 2, and the operation of the attachment / detachment control unit 31b is different.

[0163] Since the other configurations are the same as those of the battery power supply device 1, the description thereof will be omitted, and the characteristic points of the present embodiment will be described below.

[0164] The in-line battery module 2b includes battery blocks BB1b to BBNb instead of battery blocks BB1 to BBN. Hereinafter, the battery blocks BB1b to BBNb are collectively referred to as battery block BBb.

[0165] The battery block BBb further includes a grounding switching element SE, and the in-block series circuit SC of the battery block BBb further includes a disconnecting switching element SD, which is different from the battery block BB. In other respects, the battery block BBb is configured in the same manner as the battery block BB.

[0166] The grounding switching element SE is respectively interposed between the second terminal T2 of each battery block BBb and the grounding terminal TE. Note that the grounding switching element SE may be interposed between the first terminal T1 and the grounding terminal TE instead of the second terminal T2.

[0167] A disconnecting switching element SD is further added to the in-block series circuit SC of the battery block BBb. The disconnecting switching element SD is serially connected to the secondary battery B on the side opposite to the series switching element SS.

[0168] The grounding switching element SE and the disconnecting switching element SD may be semiconductor switching elements such as transistors, or may be mechanical relay switches. The grounding switching element SE and the disconnecting switching element SD are turned on and off in response to a control signal from the control unit 3b.

[0169] In addition to the same processing as the attachment / detachment control unit 31, when the attachment / detachment control unit 31b receives the designation of the battery block BBb by the touch panel display 4, the designated battery block BBb is put into a detached state, thereby turning off the series switching element SS of the battery block BBb, and further turning off the disconnecting switching element SD and turning on the grounding switching element SE of the battery block BBb.

[0170] Further, when the secondary battery B is attached to the battery block BBb from which the secondary battery B has been removed, the attachment / detachment control unit 31b turns off the grounding switching element SE and turns on the disconnection switching element SD of the battery block BBb to which the secondary battery B is attached, and further sets the battery block BBb to the joined state.

[0171] FIG. 10 is a flowchart showing an example of the attachment / detachment control process by the attachment / detachment control unit 31b shown in FIG. 9. In FIG. 9, an example is shown in which the battery blocks BB1b to BBNb are in the joined state. The attachment / detachment control will be described by taking as an example the case of removing the secondary battery B2 of the battery block BB2b from this state.

[0172] First, the attachment / detachment control unit 31b checks whether the battery block BBb has been specified by the touch panel display 4 (step S1b). When the battery block BBb has been specified by the touch panel display 4 (YES in step S1b), the attachment / detachment control unit 31b turns off the series switching element SS and turns on the bypass switching element BS of the specified battery block BBb to set it to the detached state (step S2b).

[0173] Next, the attachment / detachment control unit 31b turns off the disconnection switching element SD and turns on the grounding switching element SE of the specified battery block BBb (step S51), and then transfers the process back to step S1b.

[0174] Thus, when the user wants to use, for example, an electric bicycle, the user operates the touch panel display 4 to input, for example, "2" as the block number of the battery block BBb to which the secondary battery B for the electric bicycle is attached.

[0175] FIG. 11 is an explanatory diagram for explaining steps S2b and S51. As shown in FIG. 11, when the battery block BB2b is specified, in steps S2b and S51, as shown in FIG. 11, the series switching element SS of the battery block BB2b is turned off, the bypass switching element BS is turned on, the disconnecting switching element SD is turned off, and the grounding switching element SE is turned on.

[0176] In the state of FIG. 9 before steps S2b and S51 are executed, current is flowing through the secondary battery B2, and the secondary batteries B3 to BN on the lower potential side than the battery block BB2b are connected in series to the second terminal T2 of the battery block BB2b, and a high voltage obtained by adding the output voltages of the secondary batteries B3 to BN is applied. Therefore, if the user attempts to remove the secondary battery B2 from the battery block BB2b in this state, there is a risk of electric shock due to the current and the high voltage.

[0177] On the other hand, in the state of FIG. 11 after steps S2b and S51 are executed, since the series switching element SS and the disconnecting switching element SD of the battery block BB2b are turned off, the current flowing through the secondary battery B2 becomes zero, and the secondary battery B2 becomes electrically floating. In this state, the grounding switching element SE of the battery block BB2b is turned on, and as a result, the second terminal T2 is conducted to the grounding terminal TE, so that the secondary battery B2 becomes the grounding potential.

[0178] In this way, by making the current flowing through the secondary battery B2 zero and setting the secondary battery B2 to the grounding potential, the safety of the user who attempts to remove the secondary battery B2 is improved.

[0179] On the other hand, when the designation of the battery block BBb has not been received (NO in step S1b), the attachment / detachment control unit 31b checks whether the secondary battery B is attached to the battery block BBb from which the secondary battery B has been removed (step S3). If the secondary battery B is not attached (NO in step S3), the attachment / detachment control unit 31b returns the process to step S1b.

[0180] On the other hand, when the secondary battery B is attached to the battery block BBb from which the secondary battery B has been removed (YES in step S3), the attachment / detachment control unit 31b turns off the grounding switching element SE and turns on the disconnection switching element SD of the battery block BBb to which the secondary battery B is attached (step S52). As a result, the secondary battery B is disconnected from the grounding terminal TE.

[0181] Next, the attachment / detachment control unit 31b turns off the bypass switching element BS and turns on the series switching element SS of the battery block BBb to which the secondary battery B is attached to bring it into an active state (step S4b), and the process returns to step S1b again. As a result, the attached secondary battery B becomes available for use.

[0182] Note that it is not always necessary to execute steps S3, S52, and S4b. When NO in step S1b, step S1b may be repeated. Further, the control unit 3b may further include a temperature acquisition unit 35, a continuous energization time acquisition unit 36, and a continuous rest time acquisition unit 37, and may include a charge control unit 33a and a discharge control unit 34a instead of the charge control unit 33 and the discharge control unit 34. Further, the battery block BBb may not include the contact terminal CT.

[0183] Also, at least one of the battery blocks of the series battery module 2b may be the battery block BBb, and the series battery module may be a mixed series connection of the battery block BB and the battery block BBb.

[0184] FIG. 12 is a conceptual circuit diagram showing a modification of the series battery module 2b. As shown in FIG. 12, the series battery module 2c may include a battery block BBc instead of the battery block BBb in the series battery module 2b. The battery block BBc shown in FIG. 12 further includes an inversion circuit RC in addition to the battery block BBb. The connection wiring of the inversion circuit RC in the series battery module 2c is the same as the connection wiring of the inversion circuit RC in the series battery module 2a shown in FIG. 5, and thus the description thereof is omitted.

[0185] In the example shown in FIG. 5, the battery block BB1c is in the joined state, the battery block BB2c is in the detached state, and the battery block BB3c is in the inverted state. By using the series battery module 2c, the same effects as those of the series battery module 2a can be obtained.

[0186] Note that in the battery power supply device 1b as well, similar to the case of the battery power supply device 1, the series battery module may be one in which the battery blocks BBb and BBc are mixed and connected in series. Further, in the battery power supply devices 1, 1a, and 1b, the series battery module may be one in which the battery blocks BB, BBa, BBb, and BBc are mixed and connected in series.

Explanation of Reference Numerals

[0187] 1, 1a, 1b Battery power supply device 2, 2a, 2b Series battery module 3, 3a, 3b Control unit 4 Touch panel display (operation reception unit) 31, 31b Attachment / detachment control unit 32 SOC acquisition unit 33, 33a Charging control unit 34, 34a Discharging control unit 35 Temperature acquisition unit 36 Continuous energization time acquisition unit 37 Continuous rest time acquisition unit B, B1~BN Secondary battery BB, BB1~BBN, BBa, BB1a~BBNa, BBb, BB1b~BBNb, BBc, BB1c~BBNc Battery block BS Bypass switching element Cc Charging index Cd Discharging index CT Contact terminal A, G Group G1 First group G2 Second group Ks, Kt, Kc, Kd Coefficient Ns, Nt, Nc, Nd Normalization number P1 One end P2 The other end Continuous energization time of Pc Continuous rest time of Pd RC inversion circuit Series circuit within SC block SD disconnecting switching element SE grounding switching element SR1, SR2 inversion switching elements SS series switching element T Temperature T1 First terminal T2 Second terminal TE Grounding terminal TT1, TT2 Input / output terminals

Claims

1. A series battery module in which a plurality of battery blocks are connected in series, a detachment control unit that controls detachment of the battery blocks, and an operation reception unit that receives a designation of the battery blocks by a user, wherein each of the battery blocks has a first terminal connectable to one electrode of a secondary battery, a second terminal connectable to the other electrode of the secondary battery, a series switching element connected in series to the secondary battery connected to the first and second terminals, and a bypass switching element connected in parallel to a block internal series circuit in which the secondary battery and the series switching element are connected in series, at least one of the plurality of battery blocks is detachable from the secondary battery, in the series battery module, parallel circuits of the block internal series circuit and the bypass switching element in each battery block are connected in series, whereby the plurality of battery blocks are connected in series, the detachment control unit can control each battery block to an inclusion state in which the bypass switching element is turned off and the series switching element is turned on, and a detachment state in which the series switching element is turned off and the bypass switching element is turned on, and when a designation of the battery block is received by the operation reception unit, the designated battery block is set to the detachment state, a battery power supply device.

2. further comprising a grounding terminal for grounding, at least one of the plurality of battery blocks further includes a grounding switching element interposed between either one of the first and second terminals and the grounding terminal, the block internal series circuit of the battery block including the grounding switching element further includes a disconnecting switching element connected in series on the side of the secondary battery opposite to the series switching element, when a designation of the battery block including the grounding switching element is received by the operation reception unit, the detachment control unit turns off the series switching element by setting the designated battery block to the detachment state, and further turns off the disconnecting switching element and turns on the grounding switching element, the battery power supply device according to claim 1.

3. When the secondary battery is attached to the battery block from which the secondary battery has been removed, the attachment / detachment control unit further turns off the grounding switching element and turns on the disconnection switching element of the battery block to which the secondary battery is attached. The battery power supply device according to claim 2.

4. When the secondary battery is attached to the battery block from which the secondary battery has been removed, the attachment / detachment control unit further sets the battery block to which the secondary battery is attached to the joined state. The battery power supply device according to claim 3.

5. The battery power supply device further includes a grounding terminal for grounding, At least one of the plurality of battery blocks is capable of contacting the housing of the secondary battery and further includes a contact terminal that conducts with the grounding terminal. The battery power supply device according to claim 1.

6. An SOC acquisition unit that acquires the SOC of the secondary battery of each battery block; When charging the series battery module, the battery blocks among the plurality of battery blocks whose SOC of the secondary battery is less than 100% are grouped into a first group with a relatively large SOC of the secondary battery and a second group with a relatively small SOC of the secondary battery. By setting the battery blocks in the first group to the joined state and the battery blocks in the second group to the detached state, the battery power supply device according to claim 1 further includes a charging control unit that preferentially charges the battery blocks in the first group.

7. The charging control unit sets the battery block with the largest SOC among the battery blocks whose SOC is less than 100% as the first group. The battery power supply device according to claim 6.

8. An SOC acquisition unit that acquires the SOC of the secondary battery of each battery block; When discharging the series battery module, the battery power supply device according to claim 1 further includes a discharge control unit that sets the battery block including the secondary battery whose SOC indicates full charge to the detached state.

9. An SOC acquisition unit that acquires the SOC of the secondary battery of each battery block; The battery power supply device according to claim 1 further includes a charging control unit that controls the charging of each battery block by controlling the switching between the joined state and the detached state of each battery block so as to equalize the SOC of the secondary battery of each battery block.

10. The battery power supply device according to claim 9, wherein the charge control unit controls charging of each battery block based on at least one of the temperature of the secondary battery of each battery block, the continuous energization time which is the time during which each battery block has been in the connected state continuously retroactively from the current time, and the continuous rest time which is the time during which each battery block has been in the disconnected state continuously retroactively from the current time, in addition to the SOC.

11. an SOC acquisition unit that acquires the SOC of the secondary battery of each battery block; The battery power supply device according to claim 1, further comprising a discharge control unit that controls discharge of each battery block by controlling switching between the connected state and the disconnected state of each battery block so as to equalize the SOC of the secondary battery of each battery block.

12. The battery power supply device according to claim 11, wherein the discharge control unit controls discharge of each battery block based on at least one of the temperature of the secondary battery of each battery block, the continuous energization time which is the time during which each battery block has been in the connected state continuously retroactively from the current time, and the continuous rest time which is the time during which each battery block has been in the disconnected state continuously retroactively from the current time, in addition to the SOC.

13. The battery power supply device according to any one of claims 1 to 12, wherein at least one of the plurality of battery blocks further includes an inversion circuit that inverts the polarity of the secondary battery.

14. The battery power supply device according to any one of claims 1 to 12, wherein each of the secondary batteries is a battery pack for an electric device.

15. The battery power supply device according to any one of claims 1 to 12, further including a plurality of the secondary batteries.

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