Power storage device and power storage system

Abstract

To enhance energy density and output characteristics.SOLUTION: The energy storage apparatus 10 is an energy storage apparatus 10 mounted on a moving body S, and includes a plurality of thinly coated cells 21 coated with a first active material 26 having a thickness included in a first range between a current collector 24 and a separator 25, and a plurality of thickly coated cells 22 coated with a second active material 27 having a thickness included in a second range having a lower limit value larger than an upper limit value of the first range between the current collector 24 and the separator 25, and the thinly coated cells 21 and the thickly coated cells 22 are alternately arranged at predetermined intervals.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an electricity storage device and an electricity storage system. [Background technology]

[0002] The electric vehicle of Patent Document 1 includes a lithium ion battery as a large-capacity power storage device, and a capacitor as a high-output power storage device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-41847 Summary of the Invention [Problem to be solved by the invention]

[0004] In lithium-ion batteries, the thicker the active material coated on the current collector, the higher the energy density and the lower the output characteristics. On the other hand, the thinner the active material coated on the current collector, the lower the energy density and the higher the output characteristics. Therefore, when a power storage device composed only of lithium-ion batteries is installed in a vehicle, a problem arises in that it is not possible to achieve both high energy density and high output characteristics.

[0005] The present invention has been made in view of these points, and has as its object to increase the energy density and output characteristics. [Means for solving the problem]

[0006] A first aspect of the present invention provides an energy storage device mounted on a mobile body, comprising: a plurality of first cells in which a first active material having a thickness within 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 within a second range, the second range having a lower limit greater than the upper limit of the first range, is applied between the current collector and the separator; the first cells and the second cells are arranged alternately and at a predetermined interval.

[0007] The mobile body may further include an acquisition unit that acquires status information indicating the status of the mobile body, a first charging rate of the plurality of first cells, and a second charging rate of the plurality of second cells, and a power control unit that controls charging of the plurality of first cells and the plurality of second cells and supplying power to a driving source of the mobile body based on at least one of the status information, the first charging rate, and the second charging rate.

[0008] The power control unit may, on condition that the acquisition unit has acquired the status information indicating the speed at which the accelerator pedal of the mobile body is depressed, supply power from the plurality of first cells to the driving source if the depression speed exceeds a predetermined speed, and may supply power from the plurality of second cells to the driving source if the depression speed is equal to or less than the predetermined speed.

[0009] The power control unit may, when the acquisition unit acquires the status information indicating the depression speed of the accelerator pedal of the mobile body and the second charging rate is equal to or lower than a first threshold, supply power corresponding to the depression speed from the plurality of first cells to the driving source.

[0010] The power control unit may charge the power generated by the regenerative braking to the plurality of first cells when the first charging rate is less than a second threshold, and charge the power to the plurality of second cells when the first charging rate is equal to or greater than the second threshold, on the condition that the acquisition unit has acquired the status information indicating a state in which the regenerative braking of the mobile body is activated.

[0011] The power control unit may charge the plurality of first cells by supplying power from the plurality of second cells to the plurality of first cells, on the condition that the acquisition unit has not acquired the state information indicating that the accelerator pedal of the mobile body is depressed or that the regenerative brake of the mobile body is activated.

[0012] When the first charging rate is less than a second threshold, the power control unit may charge the plurality of first cells by supplying power from the plurality of second cells to the plurality of first cells until the second charging rate decreases to a predetermined charging rate.

[0013] A second aspect of the present invention provides an energy storage system comprising: an energy storage device mounted on a mobile body, the energy storage device including a lithium-ion battery; and an energy storage control device that controls charging and power supply of the energy storage device. The energy storage device has a plurality of first cells, each coated with a first active material having a thickness within a first range between a current collector and a separator; and a plurality of second cells, each coated with a second active material having a thickness within a second range, the second range having a lower limit greater than the upper limit of the first range, the first cells and the second cells being arranged alternately and at a predetermined interval. The energy storage control device has an acquisition unit that acquires status information indicating a status of the mobile body, first charging rates of the plurality of first cells, and second charging rates of the plurality of second cells; and a power control unit that controls charging of the plurality of first cells and the plurality of second cells and power supply to a driving source of the mobile body based on at least one of the status information, the first charging rate, and the second charging rate. [Effects of the Invention]

[0014] The present invention provides the effect of increasing the energy density and output characteristics. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram showing an overview of a moving body S according to the present embodiment. [Figure 2]1 is a cross-sectional view of a laminated structure of a thin-coated cell 21 and a thick-coated cell 22. FIG. [Figure 3] FIG. 2 is a diagram showing the arrangement of thinly coated cells 21 and thickly coated cells 22. [Figure 4] 3 is a diagram showing an example of a processing sequence in the power storage device 10. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] <Overview of Mobile Unit S> Fig. 1 is a diagram showing an overview of a mobile object S according to this embodiment. The mobile object S shown in Fig. 1 includes a control device 1, a driving source 2, and a power storage device 10. The mobile object S is a mobile object powered by mechanical energy generated by the driving source 2 including an electric motor (motor 3), and is, for example, an EV (Electric Vehicle).

[0017] The control device 1 is a device including a processor such as a CPU (Central Processing Unit) or an ECU (Electronic Control Unit), and receives an operation from a user of the mobile object S and controls the operation of a device corresponding to the operation among multiple devices provided in the mobile object S. If the mobile object S is an EV, the user is the driver of the mobile object S. As an example, when the control device 1 receives that the driver has operated the accelerator pedal, it causes the mobile object S to accelerate by supplying power from the power storage device 10 to the driving source 2.

[0018] The driving source 2 is a power source that generates power for moving the moving body S, and includes a motor 3. The motor 3 is an electric motor that converts the electric power supplied from the power storage device 10 into mechanical energy when the moving body S is moving, and transmits the mechanical energy to a driving device (not shown). The motor 3 generates regenerative electric power when the moving body S decelerates, and supplies the regenerative electric power to the power storage device 10.

[0019] The power storage device 10 is a device having a secondary battery such as a lithium ion battery, and has the function of supplying power stored in the secondary battery to the driving source 2, and charging the secondary battery with regenerated power generated by the driving source 2 and power supplied from a charging port (not shown) of the mobile object S. In FIG. 1, a plurality of thinly coated cells 21 (first cells) and a plurality of thickly coated cells 22 (second cells) are shown as the secondary batteries.

[0020] Since the mobile object S is required to have a long driving range and high output, the secondary battery installed in the mobile object S is required to have a high energy density and a high C-rate (charging / power supply speed). Since the C-rate is one of the output characteristics of a secondary battery, a high C-rate of a secondary battery means that the secondary battery has high output characteristics. However, in secondary batteries such as lithium-ion batteries, the thicker the active material coated between the current collector and separator of the cell, the higher the energy density but the lower the C-rate during charge / discharge. On the other hand, the thinner the active material coated between the current collector and separator, the higher the C-rate during charge / discharge can be but the lower the energy density. Therefore, the secondary battery installed in the mobile object S is required to have a high energy density and high output characteristics, but the lithium-ion battery used as the secondary battery in the mobile object S cannot achieve both high energy density and high output characteristics.

[0021] Therefore, the power storage device 10 has a plurality of thinly coated cells 21 in which an active material is thinly coated, and a plurality of thickly coated cells 22 in which the active material is thicker coated than the thinly coated cells 21. The power storage device 10 switches between supplying power from the thinly coated cells 21 to the driving source 2 or from the thickly coated cells 22 to the driving source 2, depending on the operation of the user of the mobile object S (for example, the speed at which the accelerator pedal is depressed). By operating in this manner, the power storage device 10 can supply power from the thinly coated cells 21 to the driving source 2 at a high C rate, and the inclusion of the thickly coated cells 22 can increase the energy density, thereby achieving both high energy density and high output characteristics.

[0022] <Configuration of Power Storage Device 10> 1, the energy storage device 10 includes an energy storage unit 20 and an energy storage control unit 30. The energy storage unit 20 includes a plurality of thinly coated cells 21, a plurality of thickly coated cells 22, and a supply unit 23. The energy storage control unit 30 includes a memory unit 31 and a processor 32. The processor 32 includes an acquisition unit 321 and a power control unit 322.

[0023] First, the configuration of the power storage unit 20 will be described. Fig. 2 is a cross-sectional view of the laminated structure of the thin-coated cell 21 and the thick-coated cell 22. The thin-coated cell 21 has current collectors 24 (positive electrode current collector 24a and negative electrode current collector 24b) and a separator 25. For example, the positive electrode current collector 24a is aluminum foil, the negative electrode current collector 24b is copper foil, and the separator 25 is polyolefin resin.

[0024] A positive electrode active material 26a, a PVDF (polyvinylidene fluoride) binder, and a conductive additive are contained between the positive electrode current collector 24a and the separator 25 of the thin-coated cell 21, and a negative electrode active material 26b and an aqueous (water-soluble) binder are contained between the negative electrode current collector 24b and the separator 25 of the thin-coated cell 21. For example, the positive electrode active material 26a is lithium cobalt oxide, the conductive additive is carbon black, and the negative electrode active material 26b is graphite.

[0025] In the thin-coated cell 21, a first active material 26 (positive electrode active material 26a and negative electrode active material 26b) having a thickness within a first range is applied between the current collector 24 and the separator 25. The first range is, for example, less than 100 μm. Specifically, in the thin-coated cell 21, the positive electrode active material 26a is applied to a thickness T1 within the first range between the positive electrode current collector 24a and the separator 25, and the negative electrode active material 26b is applied to a thickness T2 within the first range between the negative electrode current collector 24b and the separator 25. The thicknesses T1 and T2 may be the same or different.

[0026] The thick-coated cell 22 has current collectors 24 (positive electrode current collector 24a and negative electrode current collector 24b) and a separator 25. For example, the positive electrode current collector 24a is aluminum foil, the negative electrode current collector 24b is copper foil, and the separator 25 is polyolefin resin. A positive electrode active material 27a, a PVDF (polyvinylidene fluoride) binder, and a conductive additive are contained between the positive electrode current collector 24a and the separator 25 of the thick-coated cell 22, and a negative electrode active material 27b and an aqueous (water-soluble) binder are contained between the negative electrode current collector 24b and the separator 25 of the thick-coated cell 22. For example, the positive electrode active material 27a is lithium cobalt oxide, the conductive additive is carbon black, and the negative electrode active material 27b is graphite.

[0027] In the thick-coated cell 22, a second active material 27 (positive electrode active material 27a and negative electrode active material 27b) is coated between the current collector 24 and the separator 25. The second active material 27 has a thickness falling within a second range, the lower limit of which 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 110 μm or more and less than 200 μm. Specifically, in the thick-coated cell 22, a positive electrode active material 27a is coated between the positive electrode current collector 24a and the separator 25 with a thickness T3 falling within the second range, and a negative electrode active material 27b is coated between the negative electrode current collector 24b and the separator 25 with a thickness T4 falling within the second range. The thicknesses T3 and T4 may be the same or different.

[0028] In the power storage unit 20, the thinly coated cells 21 and the thickly coated cells 22 are arranged alternately and at predetermined intervals. The predetermined intervals are determined by bonding the cells together with an adhesive, and are, for example, 2 mm to 3 mm. FIG. 3 is a diagram showing the arrangement of the thinly coated cells 21 and the thickly coated cells 22. As shown in FIG. 3, in the power storage unit 20, when viewed from direction F, the thinly coated cells 21 and the thickly coated cells 22 are arranged alternately at predetermined intervals W. The intervals W may be the same or different.

[0029] By arranging the plurality of thinly coated cells 21 and the plurality of thickly coated cells 22 alternately as described above, the power storage device 10 can disperse heat generated when power is supplied from the thinly coated cells 21 or the thickly coated cells 22 to the driving source 2. That is, the power storage device 10 can suppress a local increase in temperature inside the power storage device 10 (the occurrence of so-called temperature unevenness) and make the temperature uniform. As a result, the power storage device 10 can be easily installed in a location in the moving body S that is prone to high temperatures, which can ease restrictions on the installation location.

[0030] 1, the supply unit 23 includes, for example, a flyback converter, and supplies power from each thick-coated cell 22 to each thin-coated cell 21. By operating the supply unit 23 in this manner, even if the SOC (State of Charge) of the thin-coated cell 21, which has a low energy density, drops, electricity can be supplied from the thick-coated cell 22, which has a high energy density, to the thin-coated cell 21. As a result, the energy storage device 10 can continue to supply power from the thin-coated cell 21 at a high C rate.

[0031] Next, a description will be given of the configuration of the power storage control unit 30. The storage unit 31 has a storage medium such as a read-only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), or a solid state drive (SSD). The storage unit 31 stores a program executed by the processor 32 and various information used by the power storage unit 20 to supply power to the driving source 2.

[0032] The processor 32 is a processor such as a CPU or an ECU. The processor 32 functions as an acquisition unit 321 and a power control unit 322 by executing a program stored in the storage unit 31. The processor 32 may be configured as a single processor, or may be configured as a combination of multiple processors or one or more processors and an electronic circuit.

[0033] The acquisition unit 321 acquires state information indicating the state of the mobile object S, a first charging rate of the plurality of thinly coated cells 21, and a second charging rate of the plurality of thickly coated cells 22. The state of the mobile object S is, for example, a state in which the accelerator pedal of the mobile object S is depressed, a depression speed of the accelerator pedal, and a state in which the mobile object S is operating a regenerative brake. The acquisition unit 321 acquires the state information from the control device 1 at a predetermined cycle, for example. The predetermined cycle is, for example, 0.1 seconds. The acquisition unit 321 acquires the first charging rate and the second charging rate from the power storage unit 20 at a predetermined cycle, for example.

[0034] The power control unit 322 controls the power supply to the driving source 2 of the moving object S based on at least one of the state information, the first charging rate, and the second charging rate. The power control unit 322 controls the power supply to the driving source 2 of the moving object S, for example, every time the acquisition unit 321 acquires the state information at a predetermined cycle, until the predetermined cycle has elapsed.

[0035] For example, on the condition that the acquisition unit 321 has acquired status information indicating the speed at which the accelerator pedal of the mobile object S is depressed, if the depression speed exceeds a predetermined speed, the power control unit 322 causes the thin application cells 21 to supply power to the driving source 2. The predetermined speed is a depression speed corresponding to the maximum value of the C-rates of the thick application cells 22, and is stored in the storage unit 31. For example, if the depression 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 thin application cells 21 to supply power to the driving source 2 at the C-rate corresponding to the depression speed.

[0036] For example, on condition that the acquisition unit 321 has acquired state information indicating the speed at which the accelerator pedal of the mobile object S is depressed, if the depression speed is equal to or lower than a predetermined speed, the power control unit 322 causes the multiple thick-coating cells 22 to supply power to the driving source 2. For example, if the depression speed included in the state information acquired by the acquisition unit 321 is equal to or lower than a predetermined speed stored in the storage unit 31, the power control unit 322 causes the multiple thick-coating cells 22 to supply power to the driving source 2 at a C rate corresponding to the depression speed.

[0037] By operating as described above, the power control unit 322 can supply power to the thin application cell 21 that can supply power at a high C rate when the pedaling speed is high, and can supply power to the thick application cell 22 that can supply power at a low C rate when the pedaling speed is low. As a result, the power control unit 322 can supply power to the driving source 2 from a cell that is suitable for the output required by the moving body S.

[0038] If one of the plurality of thinly coated cells 21 and the plurality of thickly coated cells 22 continues to supply power to the driving source 2, the charge rate of the cells may decrease, making it impossible to supply power from the cells. Therefore, when the charge rate of one of the plurality of cells decreases, the power control unit 322 may supply power to the driving source 2 from the other of the plurality of cells.

[0039] For example, when the acquisition unit 321 acquires state information indicating the speed at which the accelerator pedal of the mobile object S is depressed and the second charging rate is equal to or lower than the first threshold, the power control unit 322 causes the thinly applied cells 21 to supply power corresponding to the pedaling speed to the driving source 2. The first threshold is, for example, a fixed value equal to or higher than 0% and lower than 10%, and is stored in the storage unit 31. For example, even if the pedaling speed included in the state information acquired by the acquisition unit 321 is equal to or lower than a predetermined speed, when the second charging rate is equal to or lower than the first threshold, the power control unit 322 causes the thinly applied cells 21 to supply power to the driving source 2 at the C rate corresponding to the pedaling speed.

[0040] For example, even if the pedaling speed included in the status information acquired by the acquisition unit 321 exceeds a predetermined speed, if the first charging rate is equal to or less than the first threshold, the power control unit 322 causes the multiple thick-coated cells 22 to supply power to the driving source 2. In this case, the multiple thick-coated cells 22 supply power at the maximum C-rate that the multiple thick-coated cells 22 can supply. By operating in the above manner, the power control unit 322 can continue to supply power to the driving source 2 even if power cannot be supplied from multiple cells suitable for the requested output.

[0041] The power control unit 322 controls charging of the thinly coated cells 21 and the thickly coated cells 22 based on at least one of the status information, the first charging rate, and the second charging rate. For example, the power control unit 322 controls charging of the thinly coated cells 21 and the thickly coated cells 22 every time the acquisition unit 321 acquires the status information at a predetermined cycle, until the predetermined cycle has elapsed.

[0042] For example, on the condition that the acquisition unit 321 has acquired status information indicating that the regenerative braking of the mobile body S is activated, if the first charging rate is less than the second threshold, the power control unit 322 causes the power generated by the regenerative braking to be charged to the plurality of thinly coated cells 21. The second threshold is, for example, a fixed value between 90% and 100%, both inclusive, and is stored in the memory unit 31.

[0043] For example, on the condition that the acquisition unit 321 has acquired state information indicating that the regenerative braking of the mobile object S is activated, if the first charging rate is equal to or higher than the second threshold, the power control unit 322 charges the power to the multiple thickly coated cells 22. By operating as described above, the power control unit 322 can preferentially charge the regenerative energy generated by the motor 3 to the multiple thinly coated cells 21, which have a lower energy density than the multiple thickly coated cells 22. As a result, the power storage device 10 can more easily prevent a decrease in the first charging rate of the multiple thinly coated cells 21, even when the output required by the mobile object S is often high.

[0044] Furthermore, the power control unit 322 may supply power from the multiple thickly applied cells 22 to the multiple thinly applied cells 21 to suppress a decrease in the first charging rate of the multiple thinly applied cells 21. For example, the power control unit 322 charges the multiple thinly applied cells 21 by supplying power from the multiple thickly applied cells 22 to the multiple thinly applied cells 21 on the condition that the acquisition unit 321 has not acquired state information indicating that the accelerator pedal of the mobile object S is depressed or that the regenerative braking of the mobile object S is activated. In other words, when the power control unit 322 determines that the accelerator pedal of the mobile object S is not depressed and that the motor 3 is not generating regenerative energy, it causes the multiple thickly applied cells 22 to supply power to the multiple thinly applied cells 21.

[0045] For example, when the first charging rate is less than the second threshold, the power control unit 322 charges the plurality of thinly coated cells 21 by supplying power from the plurality of thickly coated cells 22 to the plurality of thinly coated cells 21 until the second charging rate falls to a predetermined charging rate. The predetermined charging rate is a charging rate at which the plurality of thickly coated cells 22 can supply power to the driving source 2 for a certain period of time, for example, 10%. As an example, when the accelerator and brake of the mobile object S are not operated, the power control unit 322 charges the plurality of thinly coated cells 21 until the first charging rates of the plurality of thinly coated cells 21 reach 100%, until the second charging rates of the plurality of thickly coated cells 22 fall to 10%.

[0046] By operating as described above, the power control unit 322 can prevent the charge rate of the plurality of thinly coated cells 21, which has a lower energy density than the plurality of thickly coated cells 22, from decreasing, and can supply power to the driving source 2 at a high C-rate from the plurality of thinly coated cells 21. That is, in the power storage device 10, the energy density and C-rate of a secondary battery such as a lithium-ion battery configured with the plurality of thinly coated cells 21 and the plurality of thickly coated cells 22 can be increased, thereby achieving both high energy density and high output characteristics.

[0047] <Processing Sequence in Power Storage Device 10> Fig. 4 is a diagram showing an example of a processing sequence in the power storage device 10. The power storage device 10 repeats the processing sequence shown in Fig. 4 at a predetermined cycle. The acquisition unit 321 acquires state information indicating the state of the moving object S from the control device 1 (S1), and identifies the state of the moving object S (S2).

[0048] When the state of the moving object S is a state in which the accelerator pedal is depressed (Case 1 in S2), the power control unit 322 identifies the accelerator pedal speed included in the state information acquired by the acquisition unit 321 (S11). When the accelerator pedal speed is equal to or greater than a predetermined speed (YES in S12), the power control unit 322 causes the thin application cells 21 to supply power to the driving source 2 (S13) and ends the process. When the accelerator pedal speed is less than the predetermined speed (NO in S12), the power control unit 322 causes the thick application cells 22 to supply power to the driving source 2 (S14) and ends the process.

[0049] When the state of the mobile object S is a state in which regenerative braking is activated (Case 2 in S2), the power control unit 322 acquires a first charging rate from the acquisition unit 321 (S21). When the first charging rate is less than the second threshold (YES in S22), the power control unit 322 charges the plurality of thinly coated cells 21 with the power generated by the driving source 2 through regenerative braking (so-called regenerative power) (S23), and ends the process. When the first charging rate is equal to or greater than the second threshold (NO in S22), the power control unit 322 charges the plurality of thickly coated cells 22 with the regenerative power (S24), and ends the process.

[0050] When the state of the mobile object S is such that the accelerator pedal is not depressed and the regenerative brake is not activated (Case 3 in S2), the power control unit 322 acquires a second charging rate from the acquisition unit 321 (S31). If the second charging rate is equal to or greater than a predetermined charging rate (YES in S32), the power control unit 322 causes the plurality of thickly coated cells 22 to supply (feed) power to the plurality of thinly coated cells 21 (S33), thereby charging the plurality of thinly coated cells 21 and terminating the process. If the second charging rate is less than the predetermined charging rate (NO in S32), the power control unit 322 terminates the process.

[0051] <First Modification> In the above description, the mobile object S is configured such that the control device 1 is provided outside the power storage device 10, but the present invention is not limited to this. The power storage device 10 may include the control device 1.

[0052] <Second Modification> In the above description, the power storage device 10 has been described as having the power storage unit 20 and the power storage control unit 30, but the present invention is not limited to this. The power storage unit 20 and the power storage control unit 30 may be provided as separate devices in the mobile object S. For example, the power storage unit 20 may be provided as a power storage device, and the power storage control unit 30 may be provided as a power storage control device in the mobile object S. Furthermore, the power storage control device may include the power storage control unit 30 and the control device 1.

[0053] <Effects of the Power Storage Device 10> As described above, the energy storage device 10 has a plurality of thinly coated cells 21 in which a first active material 26 having a thickness falling within a first range is coated between the current collector 24 and the separator 25, and a plurality of thickly coated cells 22 in which a second active material 27 having a thickness falling within a second range whose lower limit is greater than the upper limit of the first range is coated between the current collector 24 and the separator 25, and the thinly coated cells 21 and the thickly coated cells 22 are arranged alternately and at a predetermined interval.

[0054] By configuring the electricity storage device 10 in this manner, it is possible to supply power to the driving source 2 at a high C rate from the plurality of thinly coated cells 21, and it is possible to increase the energy density from the plurality of thickly coated cells 22. As a result, it is possible for the electricity storage device 10 to have high energy density and output characteristics.

[0055] The present invention has been described above using embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. For example, all or part of the device can be configured by functionally or physically distributing or integrating any unit. Furthermore, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effects of the new embodiments resulting from the combination also have the effects of the original embodiments. [Explanation of symbols]

[0056] 1. Control device 2. Drive source 3 motors 10. Energy storage device 20 Power storage unit 21 Thinly painted cel 22 Thick-painted cel 23 Supply section 24 Current collector 24a Positive electrode current collector 24b Negative electrode current collector 25 Separator 26 First active material 26a Cathode active material 26b Negative electrode active material 27 Second active material 27a Cathode active material 27b Negative electrode active material 30 Power storage control unit 31 Storage section 32 processors 321 Acquisition Department 322 Power Control Unit

Claims

1. A power storage device mounted on a moving body, a plurality of first cells in which a first active material is applied between a current collector and a separator to a thickness within a first range; a plurality of second cells each having a second active material coated thereon between the current collector and the separator, the second active material having a thickness falling within a second range whose lower limit is greater than the upper limit of the first range; The first cells and the second cells are arranged alternately and at predetermined intervals. Energy storage device.

2. an acquisition unit that acquires status information indicating a status of the moving body, a first charging rate of the plurality of first cells, and a second charging rate of the plurality of second cells; a power control unit that controls charging of the plurality of first cells and the plurality of second cells and supply of power to a driving source of the moving body based on at least one of the state information, the first charging rate, and the second charging rate. The power storage device according to claim 1 .

3. the power control unit, on condition that the acquisition unit has acquired the state information indicating a depression speed of an accelerator pedal of the mobile body, causes the plurality of first cells to supply power to the driving source when the depression speed exceeds a predetermined speed, and causes the plurality of second cells to supply power to the driving source when the depression speed is equal to or less than the predetermined speed; The power storage device according to claim 2 .

4. the power control unit causes the plurality of first cells to supply power corresponding to the depression speed to the driving source when the acquisition unit acquires the state information indicating the depression speed of the accelerator pedal of the mobile object and the second charging rate is equal to or less than a first threshold. The power storage device according to claim 2 .

5. the power control unit, on the condition that the acquisition unit has acquired the state information indicating a state in which a regenerative brake of the mobile body is activated, causes the power generated by the regenerative brake to be charged to the plurality of first cells when the first charging rate is less than a second threshold, and causes the power to be charged to the plurality of second cells when the first charging rate is equal to or greater than the second threshold; The power storage device according to claim 2 .

6. the power control unit charges the plurality of first cells by supplying power from the plurality of second cells to the plurality of first cells, on the condition that the acquisition unit has not acquired the state information indicating a state in which an accelerator pedal of the mobile body is depressed or a state in which a regenerative brake of the mobile body is activated; The power storage device according to claim 2 .

7. When the first charging rate is less than a second threshold, the power control unit charges the first cells by supplying power from the second cells to the first cells until the second charging rate decreases to a predetermined charging rate. The electricity storage device according to claim 6.

8. A power storage system including a power storage device including a lithium ion battery mounted on a mobile object, and a power storage control device that controls charging and power supply of the power storage device, The power storage device is a plurality of first cells in which a first active material is applied between a current collector and a separator to a thickness within a first range; a plurality of second cells each having a second active material coated thereon between the current collector and the separator, the second active material having a thickness falling within a second range whose lower limit is greater than the upper limit of the first range; The first cells and the second cells are arranged alternately and at predetermined intervals, The power storage control device includes: an acquisition unit that acquires status information indicating a status of the moving body, a first charging rate of the plurality of first cells, and a second charging rate of the plurality of second cells; a power control unit that controls charging of the plurality of first cells and the plurality of second cells and supply of power to a driving source of the moving body based on at least one of the state information, the first charging rate, and the second charging rate. Energy storage system.

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