Energy storage device and energy storage system

Abstract

An energy storage device (10) mounted in a moving body (S), the energy storage device (10) comprising: a plurality of thin-coated batteries (21) in which a first active material (26) having a thickness within a first range is applied between a current collector (24) and a diaphragm (25); and a plurality of thick-coated batteries (22) in which a second active material (27) having a thickness within a second range is applied between the current collector (24) and the separator (25), the lower limit value of the second range being greater than the upper limit value of the first range, and in which the thin-coated batteries (21) and the thick-coated batteries (22) are alternately arranged at predetermined intervals.

Description

Technical Field

[0001] This disclosure relates to an energy storage device and an energy storage system. Background Technology

[0002] Traditional electric vehicles include lithium-ion battery packs as high-capacity energy storage devices and capacitors as high-output energy storage devices (e.g., Japanese Unexamined Patent Application Publication No. 2010-41847). Summary of the Invention

[0003] The problem to be solved by the present invention In lithium-ion battery packs, increasing the thickness of the active material applied to the current collector increases energy density but decreases output characteristics. Conversely, decreasing the thickness of the active material applied to the current collector decreases energy density while improving output characteristics. Therefore, when an energy storage device consisting solely of a lithium-ion battery pack is installed in a vehicle, it becomes impossible to simultaneously achieve both high energy density and high output characteristics.

[0004] This disclosure is based on the above viewpoints and aims to improve energy density and output characteristics.

[0005] Problem-solving methods An energy storage device according to a first aspect of the present disclosure is installed in a mobile body. The energy storage device includes: a plurality of first batteries, wherein a first active material of a thickness within a first range is applied to the plurality of first batteries between a current collector and a separator; and a plurality of second batteries, wherein a second active material of a thickness within a second range is applied to the plurality of second batteries between a current collector and a separator, wherein a lower limit of the second range is greater than an upper limit of the first range, wherein the first batteries and the second batteries are arranged alternately at a predetermined interval.

[0006] The energy storage device may further include: an acquisition unit for acquiring state information indicating the state of the mobile body, a first charge state of a plurality of first batteries and a second charge state of a plurality of second batteries; and a power control unit for controlling (i) charging of the plurality of first batteries and the plurality of second batteries, and (ii) supplying power to a drive source of the mobile body based on the state information, the first charge state or the second charge state.

[0007] Under the condition that the acquisition unit has acquired the status information of the depressing speed when the accelerator pedal of the indicator moving body is depressed, the power control unit can enable multiple first batteries to supply power to the drive source when the depressing speed exceeds a predetermined speed, and enable multiple second batteries to supply power to the drive source when the depressing speed is equal to or less than the predetermined speed.

[0008] When the acquisition unit acquires the state information of the depressing speed when the accelerator pedal of the indicating moving body is depressed, and the second charge state is equal to or less than the first threshold, the power control unit can enable multiple first batteries to supply power to the drive source according to the depressing speed.

[0009] Under the condition that the acquisition unit has acquired the state information indicating that the regenerative brake of the moving body is in operation, when the first charge state is less than the second threshold, the power control unit can use the electrical energy generated by the regenerative brake to charge multiple first batteries, and when the first charge state is equal to or greater than the second threshold, the power control unit can use the electrical energy to charge multiple second batteries.

[0010] If the acquisition unit has not yet acquired the state information indicating that the accelerator pedal of the moving body is depressed or that the regenerative brake of the moving body is in operation, the power control unit can charge the multiple first batteries by supplying power from the multiple second batteries to the multiple first batteries.

[0011] When the first charging rate is less than the second threshold, the power control unit can charge the multiple first batteries by supplying power from multiple second batteries to multiple first batteries until the second charging rate drops to a predetermined charging rate.

[0012] When the first charge state is equal to or less than the first threshold, even if the accelerator pedal of the moving body included in the state information is pressed at a speed exceeding a predetermined speed, the power control unit can enable multiple second batteries to supply power to the drive source at the maximum value of the output of the multiple second batteries.

[0013] An energy storage system according to a second aspect of this disclosure includes: an energy storage device comprising a lithium-ion battery pack and installed in a mobile body; and an energy storage control device for controlling the charging and power supply of the energy storage device, wherein the energy storage device may include: a plurality of first batteries, wherein a first active material of a thickness within a first range is applied to the plurality of first batteries between a current collector and a separator; and a plurality of second batteries, wherein a second active material of a thickness within a second range is applied to the plurality of second batteries between a current collector and a separator, the lower limit of the second range being greater than the upper limit of the first range, wherein the first batteries and the second batteries are arranged alternately at a predetermined interval, and the energy storage control device may include an acquisition unit for acquiring state information indicating the state of the mobile body, a first charge state of the plurality of first batteries, and a second charge state of the plurality of second batteries; and a power control unit for controlling (i) the charging of the plurality of first batteries and the plurality of second batteries, and (ii) the power supply to a drive source of the mobile body, based on at least one of the state information, the first charge state, or the second charge state.

[0014] Effects of the present invention According to this disclosure, it is possible to simultaneously improve energy density and output characteristics. Attached Figure Description

[0015] Figure 1 This is a diagram showing an overview of the moving body S according to this embodiment.

[0016] Figure 2 This is a cross-sectional view of the stacked structure of thin-coated battery 21 and thick-coated battery 22.

[0017] Figure 3 This is a diagram showing the arrangement of the thin-coated battery 21 and the thick-coated battery 22.

[0018] Figure 4 This is a diagram illustrating an example of a processing sequence in the energy storage device 10.

[0019] [Symbol Explanation] 1 Controller 2. Driver Source 3 motors 10 Energy Storage Devices 20 energy storage units 21 Thin-coated battery 22 Thick Coated Battery 23 Power Supply Unit 24 current collector 24a Cathode Current Collector 24b Anode Current Collector 25 Diaphragm 26 First Active Material 26a Cathode Active Material 26b Anode Active Material 27 Second Active Material 27a Cathode Active Material 27b Anode active material 30 Energy Storage Control Unit 31 storage units 32 processors 321 Acquisition Unit 322 Power Control Unit Detailed Implementation

[0020] <Overview of the moving unit S> Figure 1 This is a diagram showing an overview of the moving body S according to this embodiment. Figure 1 The moving body S shown includes a controller 1, a drive source 2, and an energy storage device 10. The moving body S is a moving body that uses mechanical energy generated by the drive source 2 (which includes an electric motor (motor 3)) as its power source, such as an electric vehicle (EV).

[0021] Controller 1 is a device that includes a processor such as a CPU (Central Processing Unit) or ECU (Electronic Control Unit), and receives operations from a user of the mobile body S to control the operation of the device corresponding to the operation among a plurality of devices included in the mobile body S. As an example, when controller 1 receives an operation instructing the user to press the accelerator pedal, it accelerates the mobile body S by supplying power from the energy storage device 10 to the drive source 2.

[0022] Drive source 2 is a power source that generates power to move the moving body S, and includes a motor 3. Motor 3 is an electric motor that converts electrical energy supplied from energy storage device 10 into mechanical energy and transmits the mechanical energy to drive device (not shown) when the moving body S moves. During deceleration of the moving body S, motor 3 generates regenerative electrical energy and supplies the regenerative electrical energy to energy storage device 10.

[0023] The energy storage device 10 is a device that includes a secondary battery pack, such as a lithium-ion battery pack, and has the function of supplying electrical energy stored in the secondary battery pack to the drive source 2, and charging the secondary battery pack using regenerative electrical energy generated by the drive source 2 or electrical energy supplied through the charging port (not shown) of the moving body S. Figure 1 The image shows multiple thin-coated batteries 21 (first batteries) and multiple thick-coated batteries 22 (second batteries) as secondary battery packs.

[0024] Because the mobile device S requires a long cruising range and high output, the secondary battery pack installed in the mobile device S is required to have high energy density and high C-rate (charge / discharge rate). Since the C-rate is one of the output characteristics of a secondary battery pack, a high C-rate implies high output performance. However, in secondary battery packs such as lithium-ion battery packs, increasing the thickness of the active material applied between the current collector and the separator increases energy density but decreases the C-rate during charge / discharge. Conversely, decreasing the thickness of the active material applied between the current collector and the separator increases the C-rate during charge / discharge but decreases energy density. Therefore, although a secondary battery pack installed in the mobile device S requires both high energy density and high output performance, lithium-ion battery packs used as secondary battery packs in the mobile device S cannot simultaneously achieve both.

[0025] Therefore, the energy storage device 10 includes a plurality of thin-coated batteries 21 and a plurality of thick-coated batteries 22, the former having a thin layer of active material coated on them, and the latter having a thicker layer of active material coated on them than the thin-coated batteries 21. Depending on the user's operation of the mobile body S (e.g., the speed at which the accelerator pedal is depressed), the energy storage device 10 switches between supplying power to the drive source 2 from the thin-coated batteries 21 and supplying power to the drive source 2 from the thick-coated batteries 22. By operating in this way, the energy storage device 10 can supply power to the drive source 2 from the thin-coated batteries 21 at a high C-rate, and by including the thick-coated batteries 22, it can increase the energy density, thereby simultaneously achieving high energy density and high output characteristics.

[0026] <Configuration of Energy Storage Device 10> like Figure 1 As shown, the energy storage device 10 includes an energy storage unit 20 and an energy storage control unit 30. The energy storage unit 20 includes multiple thin-coated batteries 21, multiple thick-coated batteries 22, and a power supply unit 23. The energy storage control unit 30 includes a storage unit 31 and a processor 32. The processor 32 includes an acquisition unit 321 and a power control unit 322.

[0027] First, the configuration of the energy storage unit 20 will be introduced. Figure 2 This is a cross-sectional view of the stacked structure of thin-coated battery 21 and thick-coated battery 22. Thin-coated battery 21 includes current collectors 24 (cathode current collector 24a and anode current collector 24b) and separator 25. For example, cathode current collector 24a is aluminum foil, anode current collector 24b is copper foil, and separator 25 is made of polyolefin resin.

[0028] The space between the cathode current collector 24a and the separator 25 of the thin-coated battery 21 contains (i) cathode active material 26a, (ii) polyvinylidene fluoride (PVDF) binder, and (iii) conductive additive. The space between the anode current collector 24b and the separator 25 of the thin-coated battery 21 contains anode active material 26b and an aqueous (water-soluble) binder. For example, the cathode active material 26a is lithium cobalt oxide, the conductive additive is carbon black, and the anode active material 26b is graphite.

[0029] In the thin-coated battery 21, a first active material 26 (cathode active material 26a and anode active material 26b) with a thickness within a first range is applied between the current collector 24 and the separator 25. For example, the upper limit of the first range is 100 μm. Specifically, in the thin-coated battery 21, the cathode active material 26a with a thickness T1 within the first range is applied between the cathode current collector 24a and the separator 25, while the anode active material 26b with a thickness T2 within the first range is applied between the anode current collector 24b and the separator 25. The thicknesses T1 and T2 can be the same or different.

[0030] The thick-coated battery 22 includes current collectors 24 (cathode current collector 24a and anode current collector 24b) and a separator 25. For example, the cathode current collector 24a is aluminum foil, the anode current collector 24b is copper foil, and the separator 25 is made of polyolefin resin. The space between the cathode current collector 24a and the separator 25 of the thick-coated battery 22 contains (i) cathode active material 27a, (ii) polyvinylidene fluoride (PVDF) binder, and (iii) conductive additives, while the space between the anode current collector 24b and the separator 25 of the thick-coated battery 22 contains anode active material 27b and an aqueous (water-soluble) binder. For example, the cathode active material 27a is lithium cobalt oxide, the conductive additive is carbon black, and the anode active material 27b is graphite.

[0031] In the thick-coated battery 22, a second active material 27 (cathode active material 27a and anode active material 27b) is applied between the current collector 24 and the separator 25. The thickness of this second active material falls within a second range, where the lower limit of the second range is greater than the upper limit of the first range. For example, when the upper limit of the first range is 100 μm, the second range is greater than 110 μm but less than 200 μm. Specifically, in the thick-coated battery 22, cathode active material 27a with a thickness T3 within the second range is applied between the cathode current collector 24a and the separator 25, and anode active material 27b with a thickness T4 within the second range is applied between the anode current collector 24b and the separator 25. The thicknesses T3 and T4 can be the same or different.

[0032] In the energy storage unit 20, thin-coated batteries 21 and thick-coated batteries 22 are arranged alternately at predetermined intervals. The predetermined intervals are formed by bonding each battery with an adhesive, and are, for example, more than 2 mm and less than 3 mm. Figure 3 This is a diagram showing the arrangement of the thin-coated battery 21 and the thick-coated battery 22. (See diagram for example.) Figure 3 As shown, in the energy storage unit 20, viewed from direction F, thin-coated batteries 21 and thick-coated batteries 22 are arranged alternately at predetermined intervals W. Each interval W may be the same or different.

[0033] By alternately arranging multiple thin-coated batteries 21 and multiple thick-coated batteries 22 as described above, the energy storage device 10 can disperse the heat generated during power supply from either the thin-coated batteries 21 or the thick-coated batteries 22 to the drive source 2. In other words, the energy storage device 10 can suppress localized temperature rises (i.e., so-called temperature non-uniformity) within the energy storage device 10 and maintain a uniform internal temperature. Therefore, the energy storage device 10 can be more easily installed even in areas prone to heat generation on the mobile body S, thereby increasing the flexibility of the installation location.

[0034] Refer again Figure 1The power supply unit 23 includes, for example, a flyback converter and supplies power from each thick-coated battery 22 to each thin-coated battery 21. By operating the power supply unit 23 in this manner, power can be supplied from the thick-coated battery 22 to the thin-coated battery 21 even when the SOC (state of charge) of the thin-coated battery 21 with lower energy density decreases. Therefore, the energy storage device 10 is able to continuously supply power from the thin-coated battery 21 at a higher C-rate.

[0035] Next, the configuration of the energy storage control unit 30 will be described. The storage unit 31 includes storage media such as read-only memory (ROM), random access memory (RAM), hard disk drive (HDD), or solid-state drive (SSD). The storage unit 31 stores programs and various types of information executed by the processor 32 for the energy storage unit 20 to supply power to the drive source 2.

[0036] Processor 32 is a processor such as a CPU or ECU. Processor 32 operates as an acquisition unit 321 and a power control unit 322 by executing programs stored in storage unit 31. Processor 32 can be configured with a single processor, or with multiple processors or a combination of one or more processors and electronic circuitry.

[0037] The acquisition unit 321 acquires state information representing the state of the mobile body S, the first charge state of the plurality of thin-coated batteries 21, and the second charge state of the plurality of thick-coated batteries 22. The state information includes at least one of the following: the state of the mobile body S, such as the state where the accelerator pedal of the mobile body S is depressed, the depressing speed of the accelerator pedal when depressed by the driver, or the state where the regenerative brake of the mobile body S is engaged. For example, the acquisition unit 321 acquires state information from the controller 1 at predetermined intervals. The predetermined interval is, for example, 0.1 seconds. For example, the acquisition unit 321 acquires the first charge state and the second charge state from the energy storage unit 20 at predetermined intervals.

[0038] The power control unit 322 controls the supply of power to the drive source 2 of the moving body S based on at least one of the status information, a first charge state, or a second charge state. For example, the power control unit 322 controls the supply of power to the moving body S at each moment when the acquisition unit 321 acquires status information at predetermined intervals, until the predetermined interval ends.

[0039] For example, if the acquisition unit 321 has acquired the status information indicating the depressing speed of the accelerator pedal of the moving body S, and the depressing speed exceeds a predetermined speed, the power control unit 322 causes the multiple thin-coated batteries 21 to supply power to the drive source 2. The predetermined speed is the depressing speed corresponding to the maximum value of the C-rate of the multiple thick-coated batteries 22, and is stored in the storage unit 31. For example, if the depressing speed included in the status information acquired by the acquisition unit 321 exceeds the predetermined speed stored in the storage unit 31, the power control unit 322 causes the multiple thin-coated batteries 21 to supply power to the drive source 2 at a C-rate corresponding to the depressing speed.

[0040] For example, if the acquisition unit 321 has acquired the state information indicating the accelerator pedal of the moving body S is depressed, and the depressed speed is equal to or less than the predetermined speed stored in the storage unit 31, the power control unit 322 supplies power to the drive source 2 from the plurality of thick-coated batteries 22. For example, if the depressed speed included in the state information acquired by the acquisition unit 321 is equal to or less than the predetermined speed stored in the storage unit 31, the power control unit 322 supplies power to the drive source 2 from the plurality of thick-coated batteries 22 at a rate C corresponding to the depressed speed.

[0041] By operating in this manner, the power control unit 322 can supply power to the thin-coated battery 21, which is capable of supplying power at a high C-rate, when the pressing speed is high, and can supply power to the thick-coated battery 22, which is capable of supplying power at a low C-rate, when the pressing speed is low. Therefore, the power control unit 322 can supply power to the drive source 2 from a battery that is suitable for the output required by the moving body S.

[0042] When the state of supplying power to the drive source 2 from one of the multiple thin-coated batteries 21 and the multiple thick-coated batteries 22 continues, there will be a situation where the power supply stops due to the decrease in the charge state of the corresponding multiple batteries.

[0043] Therefore, when the state of charge of one of the multiple batteries decreases, the power control unit 322 can enable the other multiple batteries to supply power to the drive source 2.

[0044] For example, when the acquisition unit 321 acquires the status information indicating the depressing speed of the accelerator pedal of the moving body S and the second charge state is equal to or less than the first threshold, the power control unit 322 causes the plurality of thin-coated batteries 21 to supply power to the drive source 2 according to the depressing speed. The first threshold is, for example, a fixed value not less than 0% and less than 10%, and is stored in the storage unit 31. For example, even when the depressing speed included in the status information acquired by the acquisition unit 321 is equal to or less than a predetermined speed, if the second charge state is equal to or less than the first threshold, the power control unit 322 causes the plurality of thin-coated batteries 21 to supply power to the drive source 2 at a rate C corresponding to the depressing speed.

[0045] For example, even if the accelerator pedal depressing speed included in the status information acquired by the acquisition unit 321 exceeds a predetermined speed, if the first charge state is equal to or less than a first threshold, the power control unit 322 causes the multiple thick-coated batteries 22 to supply power to the drive source 2. In this case, the multiple thick-coated batteries 22 supply power at their maximum C-rate that they can provide. That is, even if the accelerator pedal depressing speed of the moving body S included in the status information exceeds a predetermined speed, if the first charge state is equal to or less than the first threshold, the power control unit 322 causes the multiple thick-coated batteries 22 to supply power to the drive source 2 at the maximum value output by the multiple thick-coated batteries 22. By operating in this way, the power control unit 322 can continue to supply power to the drive source 2 even when the multiple batteries cannot provide the required power output.

[0046] The power control unit 322 controls the charging of a plurality of thin-coated batteries 21 and a plurality of thick-coated batteries 22 based on at least one of status information, a first charge state, or a second charge state. For example, the power control unit 322 controls the plurality of thin-coated batteries 21 and the plurality of thick-coated batteries 22 to charge at each moment when the acquisition unit 321 acquires status information at predetermined intervals, until the predetermined interval has elapsed.

[0047] For example, if the acquisition unit 321 has acquired state information indicating that the regenerative brake of the moving body S is in operation, when the first charge state is less than a second threshold, the power control unit 322 uses the electrical energy generated by the regenerative brake to charge the multiple thin-coated batteries 21. The second threshold is, for example, a fixed value of more than 90% and less than 100%, and is stored in the storage unit 31.

[0048] For example, given that the acquisition unit 321 has acquired state information indicating that the regenerative brake of the mobile body S is in operation, when the first charge state is equal to or greater than the second threshold, the power control unit 322 uses electrical energy to charge the multiple thick-coated batteries 22. By operating in this way, the power control unit 322 can preferentially utilize the regenerative energy generated by the motor 3 to charge the multiple thin-coated batteries 21, which have a lower energy density than the multiple thick-coated batteries 22. Therefore, even when the mobile body S frequently requires high output, the energy storage device 10 is more likely to suppress the decline of the first charge state of the multiple thin-coated batteries 21.

[0049] Furthermore, the power control unit 322 can supply power from the multiple thick-coated batteries 22 to the multiple thin-coated batteries 21 to suppress the decrease in the first charge state of the multiple thin-coated batteries 21. For example, if the acquisition unit 321 has not yet acquired state information indicating that the accelerator pedal of the moving body S is depressed or that the regenerative brake of the moving body S is in operation, the power control unit 322 charges the multiple thin-coated batteries 21 by supplying power from the multiple thick-coated batteries 22 to the multiple thin-coated batteries 21. That is, when it is detected that the accelerator pedal of the moving body S is not depressed and the motor 3 is not generating regenerative energy, the power control unit 322 supplies power from the multiple thick-coated batteries 22 to the multiple thin-coated batteries 21.

[0050] For example, when the first charge state is less than a second threshold, the power control unit 322 charges the multiple thin-coated batteries 21 by supplying power from the multiple thick-coated batteries 22 to the multiple thin-coated batteries 21 until the second charge state drops to a predetermined charge state. The predetermined charge state is the charge state in which the multiple thick-coated batteries 22 can supply power to the drive source 2 within a certain period of time, for example, 10%. As an example, when neither the accelerator nor the brake of the moving body S is operated, the power control unit 322 charges the multiple thin-coated batteries 21 until the first charge rate of the multiple thin-coated batteries 21 reaches 100%, or until the second charge rate of the multiple thick-coated batteries 22 drops to 10%.

[0051] By operating in this manner, the power control unit 322 can prevent the state of charge of the multiple thin-coated batteries 21, whose energy density is lower than that of the multiple thick-coated batteries 22, from decreasing, and can supply power to the drive source 2 from the multiple thin-coated batteries 21 at a high C-rate. In other words, in the energy storage device 10, the energy density and C-rate of a secondary battery pack, such as a lithium-ion battery pack, including multiple thin-coated batteries 21 and multiple thick-coated batteries 22, can be increased, thereby simultaneously achieving high energy density and high output characteristics.

[0052] <Processing sequence in energy storage device 10> Figure 4 This is a diagram illustrating an example of a processing sequence in energy storage device 10. Energy storage device 10 repeats the process at predetermined intervals. Figure 4 The processing sequence is shown. The acquisition unit 321 acquires state information (S1) indicating the state of the moving body S from the controller 1, and identifies the state of the moving body S (S2).

[0053] When the moving body S is in the state of pressing the accelerator pedal (case 1 in S2), the power control unit 322 identifies the pressing speed included in the state information acquired by the acquisition unit 321 (S11). If the pressing speed is equal to or higher than a predetermined speed ("Yes" in S12), the power control unit 322 supplies power from the multiple thin-coated batteries 21 to the drive source 2 (S13) and ends the process. If the pressing speed is less than the predetermined speed ("No" in S12), the power control unit 322 supplies power from the multiple thick-coated batteries 22 to the drive source 2 (S14) and ends the process.

[0054] When the moving body S is in the state where the regenerative brake is in operation (case 2 in S2), the power control unit 322 acquires the first charge state from the acquisition unit 321 (S21). If the first charge state is less than the second threshold ("yes" in S22), the power control unit 322 uses the electrical energy generated by the regenerative braking of the drive source 2 (so-called regenerative electrical energy) to charge the multiple thin-coated batteries 21 (S23) and ends the process. If the first charge state is equal to or greater than the second threshold ("no" in S22), the power control unit 322 uses the regenerative electrical energy to charge the multiple thick-coated batteries 22 (S24) and ends the process.

[0055] When the state of the moving body S is neither the state of pressing the accelerator pedal nor the state of the regenerative brake being engaged (situation 3 in S2), the power control unit 322 acquires the second charge state from the acquisition unit 321 (S31). If the second charge state is equal to or greater than the predetermined charge state ("Yes" in S32), the power control unit 322 charges the multiple thin-coated batteries 21 by supplying power from the thick-coated battery 22 to the multiple thin-coated batteries 21 (S33) and ends the process. If the second charge state is less than the predetermined charge state ("No" in S32), the power control unit 322 ends the process.

[0056] <First Revision> In the above description, an example of a configuration in which a movable body S of a controller 1 is disposed outside the energy storage device 10 has been given, but this configuration is not limited thereto. The energy storage device 10 may include the controller 1.

[0057] <Second Revision> In the above description, an example configuration of the energy storage device 10 including an energy storage unit 20 and an energy storage control unit 30 has been given, but this configuration is not limited to this. The energy storage unit 20 and the energy storage control unit 30 can be provided in the mobile body S as different devices from each other. For example, the energy storage unit 20 can be provided in the mobile body S as an energy storage device, while the energy storage control unit 30 can be provided in the mobile body S as an energy storage control device. Furthermore, the energy storage control device may include the energy storage control unit 30 and the controller 1.

[0058] <Effects of Energy Storage Device 10> As described above, the energy storage device 10 includes a plurality of thin-coated batteries 21 and a plurality of thick-coated batteries 22. The former has a first active material 26 with a thickness within a first range applied between the current collector 24 and the separator 25, and the latter has a second active material 27 with a thickness within a second range applied between the current collector 24 and the separator 25. The lower limit of the second range is greater than the upper limit of the first range. The thin-coated batteries 21 and the thick-coated batteries 22 are arranged alternately at predetermined intervals.

[0059] Because the energy storage device 10 is configured in this way, it is possible to supply power to the drive source 2 from the multiple thin-coated batteries 21 at a high C-rate, and the multiple thick-coated batteries 22 can increase the energy density. Therefore, the energy storage device 10 can improve energy density and output characteristics.

[0060] This disclosure has been described based on exemplary embodiments. The technical scope of this disclosure is not limited to the scope explained by the above embodiments, and various changes and modifications can be made within the scope of this disclosure. For example, all or part of the apparatus may be configured with any functionally or physically distributed or integrated units. Furthermore, new exemplary embodiments resulting from any combination of these are also included in the exemplary embodiments. Moreover, the effects of the new exemplary embodiments resulting from the combination also have the effects of the original exemplary embodiments.

Claims

1. An energy storage device installed in a moving body, the energy storage device comprising: a plurality of first cells in which a first active material having a thickness in a first range is applied between a current collector and a separator; and a plurality of second cells in which a second active material having a thickness in a second range is applied between the current collector and the separator, the lower limit value of the second range being greater than the upper limit value of the first range, wherein the first cells and the second cells are alternately arranged at a predetermined interval.

2. The energy storage device according to claim 1, further comprising: an acquisition unit that acquires state information indicating a state of the moving body, a first state of charge of the plurality of first cells, and a second state of charge of the plurality of second cells; and a power supply control unit that controls (i) charging of the plurality of first cells and the plurality of second cells and (ii) supply of electric power to a drive source of the moving body, based on at least one of the state information, the first state of charge, or the second state of charge.

3. The energy storage device of claim 2, wherein, In a case where the acquisition unit has acquired state information indicating a depression speed at which an accelerator pedal of the moving body is depressed, when the depression speed exceeds a predetermined speed, the power supply control unit causes the plurality of first cells to supply electric power to the drive source, and when the depression speed is equal to or less than the predetermined speed, the power supply control unit causes the plurality of second cells to supply electric power to the drive source.

4. The energy storage device of claim 2, wherein, When the acquisition unit acquires state information indicating a depression speed at which an accelerator pedal of the moving body is depressed and the second state of charge is equal to or less than a first threshold value, the power supply control unit causes the plurality of first cells to supply electric power to the drive source in accordance with the depression speed.

5. The energy storage device of claim 2, wherein, In a case where the acquisition unit has acquired state information indicating a state in which a regenerative brake of the moving body is in operation, when the first state of charge is less than a second threshold value, the power supply control unit charges the plurality of first cells with electric power generated by the regenerative brake, and when the first state of charge is equal to or greater than the second threshold value, the power supply control unit charges the plurality of second cells with the electric power.

6. The energy storage device of claim 2, wherein, In a case where the acquisition unit has not acquired state information indicating a state in which an accelerator pedal of the moving body is depressed or a state in which a regenerative brake of the moving body is in operation, the power supply control unit charges the plurality of first cells by supplying electric power from the plurality of second cells to the plurality of first cells.

7. The energy storage device of claim 6, wherein, When the first charging rate is less than a second threshold value, the power supply control unit charges the plurality of first cells by supplying electric power from the plurality of second cells to the plurality of first cells until the second charging rate falls to a predetermined charging rate.

8. The energy storage device of claim 2, wherein, Even when a depression speed of an accelerator pedal of the moving body included in the state information exceeds a predetermined speed, the power supply control unit causes the plurality of second cells to supply electric power to the drive source at a maximum value of an output of the plurality of second cells when the first state of charge is equal to or less than a first threshold value.

9. An energy storage system comprising: An energy storage device including a lithium-ion battery and installed in a moving body; and an energy storage control device that controls charging and discharging of the energy storage device, wherein the energy storage device includes: a plurality of first batteries in which a first active material having a thickness in a first range is applied between a current collector and a separator; and a plurality of second batteries in which a second active material having a thickness in a second range is applied between the current collector and the separator, the second range having a lower limit value greater than an upper limit value of the first range, wherein the first batteries and the second batteries are alternately arranged at predetermined intervals, and the energy storage control device includes: an acquisition unit that acquires state information indicating a state of the moving body, a first state of charge of the plurality of first batteries, and a second state of charge of the plurality of second batteries; and a power supply control unit that controls (i) charging of the plurality of first batteries and the plurality of second batteries and (ii) power supply to a drive source of the moving body, based on at least one of the state information, the first state of charge, or the second state of charge.

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