Estimation method, program, storage medium, estimation device and charging and discharging system

Abstract

To provide an estimation method for estimating a degree of correlation with deterioration of a power storage device including internal resistance value, etc.; and to provide a program, a storage medium, an estimation device and a charging and discharging system.SOLUTION: An estimation method for estimating a degree of correlation with degradation of a battery in a charging and discharging system in which a plurality of charging and discharging devices and a control server and an analysis server via a network 30 (an estimation device and a computer) carry out charging or discharging to or from a plurality of batteries, includes: a charging and discharging step in which the charging and discharging devices charge or discharge a power storage device; a pause step for pausing charging or discharging in the charging and discharging step; an acquisition step for making the analysis server acquire at least either of a first voltage which is the voltage of the power storage device in the charging and discharging step and a second voltage which is the voltage of the power storage device in the pause step; and an estimation step for estimating an internal resistance value and a degree of degradation on the basis of at least either of the first voltage and the second voltage.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an estimation method, a program, a storage medium, an estimation device, and a charge / discharge system. [Background technology]

[0002] Patent Document 1 discloses an internal resistance estimation method for estimating the internal resistance value of a secondary battery. In this internal resistance estimation method, the internal resistance value of the secondary battery is estimated taking into consideration the conditions when the secondary battery is charged. Specifically, when a secondary battery attached to a charger is being charged, the voltage, current, and temperature of the secondary battery are acquired. Next, the internal resistance value of the secondary battery is estimated based on the acquired voltage, current, and temperature. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 235481 Summary of the Invention [Problem to be solved by the invention]

[0004] The internal resistance value of an electricity storage device such as a secondary battery changes as it is used. The change in the internal resistance value changes the output from the electricity storage device or the degree of temperature rise of the electricity storage device. By understanding the change in the internal resistance value of the electricity storage device, it is possible to determine the deterioration of the electricity storage device. The change in the internal resistance value can be one of the criteria for recovering the electricity storage device.

[0005] Incidentally, the change in the internal resistance value depends on the SOC of the power storage device. When the SOC usage range is set for each commercial product in which the power storage device is used, it is necessary to accurately grasp the change in the internal resistance value relative to the SOC usage range. However, when the SOC changes sharply over time during charging of the power storage device, it becomes difficult to measure the SOC, and it becomes difficult to estimate the internal resistance value according to the SOC.

[0006] Moreover, the SOC depends on the OCV (open circuit voltage) of the power storage device. Therefore, it is conceivable to measure a predetermined voltage value while the power storage device is being charged, and estimate the internal resistance value based on the measured voltage value. However, the relationship between the SOC and the voltage varies depending on the type, model, etc. of the power storage device. Therefore, if the voltage value serving as the measurement standard is a fixed value, it becomes difficult to accurately estimate the internal resistance value when the type, model, etc. of the power storage device changes.

[0007] Furthermore, there is a method in which the charging of the storage device is temporarily suspended and the internal resistance value is estimated during the suspension time. However, if a suspension time is provided, it takes time to fully charge the storage device, so the suspension time needs to be as short as possible. In addition, since the required suspension time varies depending on the type and model of the storage device, it is difficult to maintain a balance between the charging time and the suspension time if the suspension time is a fixed value.

[0008] As described above, it has been difficult to accurately estimate the degree to which internal resistance or the like correlates with deterioration of the power storage device.

[0009] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0010] A first aspect of the present invention is an estimation method for estimating a degree of correlation with deterioration of an energy storage device, the estimation method including a charge / discharge step of charging or discharging the energy storage device, a pause step of pausing charging or discharging in the charge / discharge step, an acquisition step of acquiring at least one of a first voltage which is a voltage of the energy storage device in the charge / discharge step and a second voltage which is a voltage of the energy storage device in the pause step, and an estimation step of estimating the degree of correlation with the deterioration based on at least one of the first voltage and the second voltage.

[0011] A second aspect of the present invention is a program for causing a computer to execute the estimation method of the first aspect.

[0012] A third aspect of the present invention is a storage medium that stores the program according to the second aspect.

[0013] A fourth aspect of the present invention is an estimation device for estimating a degree of correlation with deterioration of an energy storage device, the estimation device comprising: an acquisition unit that acquires at least one of a first voltage which is a voltage of the energy storage device when the energy storage device is charged or discharged, and a second voltage which is a voltage of the energy storage device when charging or discharging of the energy storage device is suspended; and an estimation unit that estimates the degree of correlation with the deterioration based on the one of the voltages acquired by the acquisition unit.

[0014] A fifth aspect of the present invention is a charge / discharge system including a charge / discharge device that charges or discharges an electricity storage device, and the estimation device according to the fourth aspect. Effect of the Invention

[0015] According to the present invention, it is possible to accurately estimate the degree of correlation with deterioration of the power storage device. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a configuration diagram of a charge / discharge system according to this embodiment. [Diagram 2] FIG. 2 is a block diagram of the charging and discharging system. [Diagram 3] 3A and 3B are diagrams showing a battery list. [Figure 4] FIG. 4 is a timing chart showing the charging process for the battery. [Diagram 5] FIG. 5 is a timing chart illustrating the details of the charging process of FIG. [Figure 6] FIG. 6 is a diagram showing data acquired by the management server and the analysis server. [Figure 7] 7A and 7B are diagrams illustrating the process of estimating the internal resistance value. [Figure 8]FIG. 8 is a diagram showing the relationship between the SOC and the internal resistance value. [Figure 9] FIG. 9 is a diagram showing the degree of deterioration of a battery. [Figure 10] FIG. 10 is a flowchart showing the operation of the charge / discharge system. [Figure 11] FIG. 11 is a flowchart showing the operation of the charge / discharge system. [Figure 12] FIG. 12 is a flowchart showing the operation of the charge / discharge system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Fig. 1 is a configuration diagram of a charge / discharge system 10 according to this embodiment. The charge / discharge system 10 includes a plurality of charge / discharge devices 12, a management server 14, and an analysis server 16 (estimation device, computer). The charge / discharge system 10 charges or discharges a plurality of batteries 18 (power storage devices). As will be described later, the charge / discharge system 10 is also capable of estimating an internal resistance value R of each of the plurality of batteries 18.

[0018] Each of the multiple charging / discharging devices 12 is a charging station capable of accommodating multiple batteries 18. Each of the multiple charging / discharging devices 12 stores and charges / discharges the multiple batteries 18. FIG. 1 illustrates a case where two charging / discharging devices 12 are provided. In the following description, one of the two charging / discharging devices 12 may be referred to as a first charging / discharging device 20, and the other may be referred to as a second charging / discharging device 22.

[0019] Specifically, each of the two charge / discharge devices 12 has a housing 24. One side of the housing 24 is provided with a plurality of slots 26. Each of the plurality of slots 26 is provided with an opening / closing cover (not shown). A user can insert or remove the battery 18 into or from the slot 26 by opening the opening / closing cover of any one of the plurality of slots 26 to expose the slot 26.

[0020] Each of the multiple batteries 18 is detachable from the charging / discharging device 12. For example, a battery pack of detachable lithium ion batteries is suitable as the batteries 18. Each of the multiple charging / discharging devices 12 charges or discharges the multiple batteries 18 with the multiple batteries 18 attached to the slots 26 and with the opening / closing lid closed.

[0021] An operation panel 28 that can be operated by a user is disposed on one surface of the housing 24. The operation panel 28 is, for example, a touch panel.

[0022] Each of the multiple charging / discharging devices 12 can wirelessly transmit and receive information or signals to and from the management server 14 via the network 30. In addition, the management server 14 can wirelessly transmit and receive information or signals to and from the analysis server 16.

[0023] Each of the multiple charging / discharging devices 12 can also transmit and receive information or signals to and from the management server 14 via a wired connection. The management server 14 can also transmit and receive information or signals to and from the analysis server 16 via a wired connection. Furthermore, each of the multiple charging / discharging devices 12 and the management server 14 can also transmit and receive information or signals via a CAN (Controller Area Network). Furthermore, the management server 14 and the analysis server 16 can also transmit and receive information or signals via a CAN.

[0024] Fig. 2 is a block diagram of the charging / discharging system 10. Fig. 2 representatively illustrates one of two charging / discharging devices 12. Fig. 2 also illustrates a case in which a battery 18 is accommodated in each of two slots 26 of one charging / discharging device 12.

[0025] The charging / discharging device 12 has a calculation unit 32, a communication unit , an operation panel and a storage unit . Each of the plurality of batteries 18 has a voltage detection unit , a current detection unit 40 and a temperature detection unit .

[0026] Each of the multiple batteries 18 has multiple cells (not shown). In each of the multiple batteries 18, one cell block (not shown) is configured by electrically connecting the multiple cells in series. In each of the multiple batteries 18, the multiple cell blocks are electrically connected in parallel. That is, the multiple cell blocks are electrically connected in parallel to the output terminals (not shown) of the multiple batteries 18.

[0027] The voltage detection unit 38 sequentially detects the voltage value of each cell for one cell block. The current detection unit 40 sequentially detects the current I (charging current) flowing into the battery 18 via the output terminal when the battery 18 is being charged. Furthermore, the current detection unit 40 sequentially detects the current I (discharging current) flowing out of the battery 18 via the output terminal when the battery 18 is being discharged. The temperature detection unit 42 sequentially detects the temperature T of the battery 18. The battery 18 sequentially outputs the detection results of the voltage detection unit 38, the current detection unit 40, and the temperature detection unit 42 to the charge / discharge device 12.

[0028] The calculation unit 32 is a processor of the charging / discharging device 12. The calculation unit 32 realizes the functions of a control unit 44, an acquisition unit 46, and a charging / discharging processing unit 48 by reading and executing a program stored in the storage unit 36.

[0029] The control unit 44 controls each unit of the charging / discharging device 12. The acquisition unit 46 acquires each detection result output from each of the multiple batteries 18. The charging / discharging processing unit 48 charges or discharges each of the multiple batteries 18.

[0030] Operation panel 28 has a display unit 50 and an operation unit 52. Display unit 50 is a display screen of operation panel 28. Operation unit 52 is an operation button of operation panel 28. A user can input various information or instructions to charging / discharging device 12 by operating operation unit 52.

[0031] The communication unit 34 transmits and receives information or signals to and from the management server 14. For example, the communication unit 34 transmits the detection results of each of the multiple batteries 18 acquired by the acquisition unit 46 to the management server 14.

[0032] In addition to the above programs, the battery list shown in Fig. 3A and Fig. 3B and charge / discharge setting information are stored in the storage unit 36. The storage unit 36 ​​(see Fig. 2) can also store each detection result acquired by the acquisition unit 46.

[0033] The battery list is a list that stores the mode when the charge / discharge processing unit 48 charges or discharges each of the multiple batteries 18. The battery list stores an ID (battery ID) given to each of the multiple batteries 18 and a flag (measurement flag) indicating the mode. When the flag is 0, the normal mode is selected. When the flag is 1, the measurement mode is selected.

[0034] In the normal mode, the charge / discharge processing unit 48 performs normal charging or discharging processing on the battery 18. Specifically, when performing charging processing in the normal mode, the charge / discharge processing unit 48 continuously charges the battery 18 (see FIG. 2) until the voltage V or SOC (amount of power) of the battery 18 (see FIG. 2) changes from a first amount to a second amount, as shown by a dashed line in FIG. 4. In the case of FIG. 4, the charge / discharge processing unit 48 performs charging processing with the time taken for the voltage V to change from the voltage value Vt0, which is the first amount, to the voltage value Vf, which is the second amount (the time from time t0 to time t4) being one cycle.

[0035] The voltage V of the battery 18 is the voltage of one cell block. In other words, the voltage V is the sum of the voltage values ​​of the cells that make up one cell block. For ease of explanation, FIG. 4 shows exaggerated changes in the voltage V and current I over time.

[0036] In the normal mode, the acquisition unit 46 (see FIG. 2) acquires each detection result of the battery 18 at a constant period (interval Tn in FIG. 5). The communication unit 34 sequentially transmits each detection result acquired by the acquisition unit 46 to the management server 14.

[0037] In the measurement mode, the charge / discharge processing unit 48 performs a charging process or a discharging process on the battery 18 while performing a detection process of the voltage V, the current I, and the temperature T for estimating an internal resistance value R of the battery 18, which will be described later. Specifically, when performing a charging process in the measurement mode, the charge / discharge processing unit 48 alternately repeats a charging state and a resting state on the battery 18 until the voltage V or the SOC (amount of power) of the battery 18 (see FIG. 2) changes from a first amount to a second amount, as shown by a solid line in FIG. 4. That is, the charge / discharge processing unit 48 performs on / off control, with the time until the voltage V or the SOC changes from the first amount to the second amount (the time from time t0 to time t4) being one cycle.

[0038] At this time, the acquisition unit 46 acquires the voltage V in the charging state as the first voltage V1, and acquires the voltage V in the resting state as the second voltage V2. The first voltage V1 is the CCV (closed circuit voltage) of the battery 18. The second voltage V2 is the OCV of the battery 18.

[0039] Moreover, the acquisition unit 46 acquires the current I in the charging state as a first current I1, and acquires the current I in the hibernation state as a second current I2.

[0040] After the charging in the measurement mode is completed, the communication unit 34 transmits all the detection results acquired by the acquisition unit 46 to the management server 14.

[0041] When performing a discharge process in the normal mode or the measurement mode, the charge / discharge processing unit 48 performs a discharge process on the battery 18 until the voltage V or the SOC changes from the first amount to the second amount, similar to the charging process.

[0042] The charge / discharge setting information is a parameter for charging or discharging when the measurement mode is executed. The details of the parameters will be described later.

[0043] The battery list and the charge / discharge setting information are provided by the management server 14. Therefore, when the battery list and the charge / discharge setting information are provided from the management server 14 to the charge / discharge device 12, the battery list and the charge / discharge setting information stored in the storage unit 36 ​​are updated. In other words, the contents of the battery list and the charge / discharge setting information stored in the storage unit 36 ​​can be changed by the management server 14.

[0044] Fig. 3A illustrates a case where the charging or discharging process to be performed on the two batteries 18 (see Fig. 2) is in normal mode. Fig. 3B illustrates a case where the charging or discharging process for one of the two batteries 18 is in normal mode, and the charging or discharging process for the other battery 18 is in measurement mode.

[0045] As shown in FIG. 2, the management server 14 includes a calculation unit 54, a communication unit 56, and a storage unit 58.

[0046] The communication unit 56 transmits and receives information or signals to and from the communication unit 34 of the charging / discharging device 12. The communication unit 56 also transmits and receives information or signals to and from the analysis server 16.

[0047] The calculation unit 54 is a processor of the management server 14. The calculation unit 54 reads out and executes a program stored in the storage unit 58, thereby realizing the functions of a control unit 60, an acquisition unit 62, a counting unit 64, a determination unit 66, a list update unit 68, and a setting change unit 70.

[0048] The control unit 60 controls each unit of the management server 14. The acquisition unit 62 acquires each detection result for each of the plurality of batteries 18 received by the communication unit 56.

[0049] Note that, for example, when communication is via CAN, the charging / discharging device 12 and the management server 14 transmit and receive information or signals at a predetermined communication cycle. In this case, the communication cycle between the charging / discharging device 12 and the management server 14 is shorter than the interval at which the acquiring unit 62 acquires each detection result. Therefore, the acquiring unit 62 acquires, for example, the voltage of each cell constituting a cell block, and acquires the voltage V of the battery 18 by summing up the acquired voltages of each cell. Also, the acquiring unit 62 acquires the current I by, for example, taking the time average of the acquisition interval at the acquiring unit 62 for the current I sent from the charging / discharging device 12.

[0050] When the acquisition unit 62 acquires each detection result for each of the multiple batteries 18 in the measurement mode, the counting unit 64 counts the number of times that the battery 18 has been replaced in the charging / discharging device 12 between the previous charging / discharging process in the measurement mode and the current charging / discharging process in the measurement mode.

[0051] The determination unit 66 determines whether or not to change the battery list and the charge / discharge setting information based on the count number by the count unit 64. For example, if the count number is equal to or greater than a threshold, the determination unit 66 determines that the battery list and the charge / discharge setting information should be changed.

[0052] The list update unit 68 changes the contents of the battery list in response to the determination result of the determination unit 66. Specifically, the list update unit 68 changes the flags in the battery list shown in Figures 3A and 3B to 0 or 1.

[0053] The setting change unit 70 receives the determination result from the determination unit 66 and changes the charge / discharge setting information.

[0054] When the list update unit 68 updates the battery list and the setting change unit 70 changes the charge / discharge setting information, the communication unit 56 transmits the updated battery list and the changed charge / discharge setting information to the charge / discharge device 12. When the acquisition unit 62 acquires each detection result for each of the multiple batteries 18 in the measurement mode, the communication unit 56 transmits each detection result acquired by the acquisition unit 62 to the analysis server 16.

[0055] The analysis server 16 includes a calculation unit 72 , a communication unit 74 , and a storage unit 76 .

[0056] The communication unit 74 transmits and receives information or signals to and from the communication unit 56 of the management server 14 .

[0057] The calculation unit 72 is a processor of the analysis server 16. The calculation unit 72 realizes the functions of a control unit 78, an acquisition unit 80, an estimation unit 82, and a determination unit 84 by reading and executing a program stored in the storage unit 76.

[0058] The control unit 78 controls each unit of the analysis server 16. The acquisition unit 80 acquires each detection result for each of the multiple batteries 18 received by the communication unit 74. The analysis server 16 and the management server 14 transmit and receive information or signals at a predetermined communication cycle. Therefore, when the acquisition unit 80 acquires each detection result at a cycle shorter than the communication cycle, each detection result acquired by the acquisition unit 80 is acquired as an average value of each detection result in the communication cycle.

[0059] The estimation unit 82 estimates the degree of correlation with deterioration of the battery 18 based on each detection result acquired by the acquisition unit 80. Specifically, the estimation unit 82 estimates the internal resistance value R or the degree of deterioration SOH of the battery 18.

[0060] The determination unit 84 determines whether or not the battery 18 should be recovered based on the internal resistance value R or the degree of deterioration SOH estimated by the estimation unit 82.

[0061] FIG. 4 is a timing chart showing charging in the normal mode (dashed line) and charging in the measurement mode (solid line) performed by the charge / discharge device 12 (see FIG. 2).

[0062] In the normal mode, the charge / discharge processing unit 48 starts charging the battery 18 at time t0. In this case, the charge / discharge processing unit 48 passes a current I (charging current) having a current value Ic to the battery 18 from time t0. As a result, the voltage V of the battery 18 gradually increases from the voltage value Vt0 over time.

[0063] Thereafter, when the voltage V reaches the voltage value Vf at time t1, the charge / discharge processing unit 48 reduces the current I flowing to the battery 18 from Ic. As a result, the voltage V gradually decreases over time and then increases again. Thereafter, when the voltage V reaches the voltage value Vf again at time t2, the charge / discharge processing unit 48 reduces the current I flowing to the battery 18 again.

[0064] In this way, the charge / discharge processing unit 48 repeats the rise and fall of the voltage V in a voltage region near the voltage value Vf while gradually lowering the current I from time t1 onward. After that, when the voltage value Vf is reached at time t3, the battery 18 is fully charged and the current I becomes 0. After that, at time t4, the charge / discharge processing unit 48 stops the charging process.

[0065] In the normal mode, the acquisition unit 46 sequentially acquires the detection results of the voltage V, the current I, and the temperature T of the battery 18 from the voltage detection unit 38, the current detection unit 40, and the temperature detection unit 42. The communication unit 34 sequentially transmits each of the detection results acquired by the acquisition unit 46 to the management server 14.

[0066] In the normal mode, the acquisition unit 62 of the management server 14 sequentially acquires the detection results of the voltage V, the current I, and the temperature T of the battery 18. The communication unit 56 sequentially transmits each detection result acquired by the acquisition unit 62 to the analysis server 16.

[0067] Furthermore, in the normal mode, the acquisition unit 80 of the analysis server 16 sequentially acquires the detection results of the voltage V, the current I, and the temperature T of the battery 18. The acquired detection results are stored in the storage unit .

[0068] On the other hand, in the measurement mode, the charge / discharge processing unit 48 starts charging the battery 18 at time t0. In this case, the charge / discharge processing unit 48 also passes a current I (charging current) of a current value Ic to the battery 18 from time t0. As a result, the voltage V of the battery 18 gradually increases from the voltage value Vt0 over time.

[0069] 4 and 5, in the measurement mode, charging and pausing of charging of the battery 18 are alternately and repeatedly performed from time t0. Specifically, the charge / discharge processing unit 48 charges the battery 18 during a charging time Tc. Also, the charge / discharge processing unit 48 pauses charging of the battery 18 during a pause time To.

[0070] In detail, from time t0 to time t11, a current I having a current value Ic is caused to flow through the battery 18, thereby charging the battery 18. As a result, the voltage V gradually increases over time from the voltage value Vt0. As a result, at time t11, the voltage V reaches the threshold voltage Vt1.

[0071] From time t11 to time t12, the current I flowing through the battery 18 is set to 0, thereby suspending charging of the battery 18. As a result, the voltage V gradually decreases over time from the threshold voltage Vt1. In other words, the threshold voltage Vt1 is a voltage threshold when the battery 18 is shifted from a charging state to a suspended state. Note that the first voltage V1 is the CCV of the battery 18 and the second voltage V2 is the OCV of the battery 18, and therefore the decrease in voltage V in the suspended state is a voltage drop due to the internal resistance value R (CCV=OCV+R×I).

[0072] Thereafter, at time t12, the charge / discharge processing unit 48 resumes charging the battery 18 by again flowing the current I with a current value Ic through the battery 18. This causes the voltage V to gradually increase over time. As a result, at time t13, which is the charging time Tc after time t12, the voltage V reaches the threshold voltage Vt2. Thereafter, the charge / discharge processing unit 48 transitions the battery 18 from the charging state to the resting state.

[0073] In this way, in the measurement mode, the charge and discharge processing unit 48 alternately repeats the charging state (charging time Tc) and the rest state (rest time To). That is, the charge and discharge processing unit 48 performs on-off control charging on the battery 18 by repeatedly flowing a constant current of the current value Ic through the battery 18. As a result, the voltage V of the battery 18 increases toward the voltage value Vf while repeating an increase and a decrease over time.

[0074] Note that in FIG. 4, Vt1, Vt2, Vt3, Vt4, and Vt5 are threshold voltages (Vt1 < Vt2 < Vt3 < Vt4 < Vt5). As described above, when the voltage V reaches the threshold voltages Vt1, Vt2, Vt3, Vt4, and Vt5, the battery 18 shifts from the charging state to the rest state.

[0075] Thereafter, when the voltage V once reaches the voltage value Vf at the time point t14, the charge and discharge processing unit 48 decreases the current I flowing through the battery 18 from the current value Ic in the same manner as in the normal mode. As a result, the voltage V gradually decreases over time and then increases again. When the voltage V reaches the voltage value Vf again, the charge and discharge processing unit 48 decreases the current I flowing through the battery 18 again. That is, after the time point t14, the charge and discharge processing unit 48 does not shift the battery 18 to the rest state.

[0076] In this way, also in the measurement mode, the charge and discharge processing unit 48 repeatedly increases and decreases the voltage V in the voltage region near the voltage value Vf by gradually decreasing the current I after the time point t14. Thereafter, at the time point t4, the charge and discharge processing unit 48 stops the charging process.

[0077] FIG. 5 is a diagram showing the timing of acquisition of the voltage V and the current I in the measurement mode. The acquisition subject here is the acquisition unit 46 (see FIG. 2). Alternatively, it may be the acquisition unit 62 or the acquisition unit 80. In the following description, the case where the acquisition unit 46 acquires is described.

[0078] As described above, in the measurement mode, the charging state and the resting state are alternately and repeatedly executed. Fig. 5 representatively illustrates the timing of acquiring the voltage V and the current I in the charging state from time t0 to t11, the resting state from time t11 to t12, and the charging state from time t12 to t13.

[0079] In the measurement mode, the voltage V and the current I are acquired at the following timing. Specifically, before and after switching from the hibernation state to the charging state, the voltage V and the current I are acquired at intervals Tct and Tot that are shorter than the acquisition interval Tn in the normal mode. In addition, during other time periods, the acquisition unit 46 acquires the voltage V and the current I at the acquisition interval Tn in the normal mode.

[0080] In detail, in the charging state, the acquisition unit 46 acquires the voltage V (first voltage V1) and the current I (first current I1) at intervals Tct from the time when charging starts (times t0, t12) until a certain time Tcs (times t21, t23). Also, in the charging state, the acquisition unit 46 acquires the voltage V (first voltage V1) and the current (first current I1) at intervals Tn from after the time Tcs until the time when charging is paused (times t11, t13).

[0081] Furthermore, in the pause state, the acquisition unit 46 acquires the voltage V (second voltage V2) and the current I (second current I2) at intervals Tot until a certain time Tos before the pause end time (time t12). Also, in the pause state, the acquisition unit 46 acquires the voltage V (second voltage V2) and the current (second current I2) at intervals Tn from the pause start time (t11) until the acquisition of the voltage V and the current I at the interval Tot starts (time t22).

[0082] That is, the acquisition unit 46 acquires the voltage V and the current I in detail during a certain time period before and after switching from the resting state to the charging state.

[0083] The setting change unit 70 changes the contents of the charge / discharge setting information. The charge / discharge setting information is a parameter related to charging or discharging the battery 18. The parameters are the number of times the charging state or discharging state transitions to the hibernation state, the threshold voltage (threshold voltages Vt1, Vt2, Vt3, Vt4, Vt5 in FIG. 4) or threshold power amount (SOC threshold) when transitioning from the charging state or discharging state to the hibernation state, the time of the hibernation state (hibernation time To), the acquisition mode of the voltage V (second voltage V2) in the hibernation state, and the acquisition mode of the voltage V (first voltage V1) in the charging state.

[0084] Among these, the number of times of transition from the charging state or discharging state to the pause state is the number of times that the threshold voltages Vt1, Vt2, Vt3, Vt4, and Vt5 are set, for example, five times in the cases of Figs.

[0085] The acquisition mode of the voltage V in the idle state (second voltage V2) includes at least one of the period (idle time To), the number of times, the frequency, and the period (interval Tot, interval Tn) for acquiring the voltage V. The interval Tot and the interval Tn are sampling periods for acquiring the second voltage V2. The interval Tot is a sampling period for acquiring the second voltage V2 in detail. The interval Tn is a sampling period for acquiring the second voltage V2 at the same time interval as in the normal mode.

[0086] The manner of acquiring the voltage V in the charging state (first voltage V1) includes at least one of the period (charging time Tc), the number of times, the frequency, and the cycle (interval Tct, interval Tn) for acquiring the voltage V. The interval Tct and the interval Tn are sampling cycles for acquiring the first voltage V1. The interval Tct is a sampling cycle for acquiring the first voltage V1 in detail. The interval Tn is a sampling cycle for acquiring the first voltage V1 at the same time interval as in the normal mode.

[0087] Therefore, the charge / discharge processing unit 48 sets parameters relating to charging and discharging of the battery 18 based on the charge / discharge setting information stored in the storage unit 36, and then executes the charge / discharge processing in the measurement mode.

[0088] In this embodiment, for example, Tot=Tct=1 second, Tos=Tcs=3 seconds, Tn=1 minute, and To=2 minutes.

[0089] The setting change section 70 is capable of changing at least one of these parameters.

[0090] In addition, the setting change unit 70 can change at least one of the above parameters based on at least one of the type, model, current state, degree of correlation with current deterioration (internal resistance value R, deterioration level SOH) of the battery 18, and past usage patterns.

[0091] The type of battery 18 includes the material of the cells constituting battery 18, the type of chemical reaction, etc. The model of battery 18 includes the version of battery 18. The current state of battery 18 includes the current temperature T of battery 18. The past usage of battery 18 includes the usage history of battery 18, the number of replacements, etc.

[0092] Regarding the execution of the measurement mode, the list update unit 68 may change a flag in the battery list from 0 to 1 according to the degree of deterioration of the battery 18. For example, the list update unit 68 may change the flag to 1 when the battery 18 is in an area where it is prone to deterioration, or when it is near an area where a resistance increase rate, which will be described later, is high. This makes it possible to increase the frequency with which the measurement mode is executed for the battery 18 in a situation where deterioration of the battery 18 is advanced. Also, it becomes possible for the management server 14 to adjust the frequency with which the measurement mode is executed.

[0093] The setting change unit 70 can also set the charge / discharge setting information so that the acquisition units 46, 62, and 80 do not acquire each detection result unnecessarily. Specifically, the setting change unit 70 may set a threshold value of the SOC when charging in the measurement mode is started. This makes it possible to prohibit the execution of the measurement mode when the measurement mode is executed with a relatively high SOC, and there are few points of the threshold voltage, making it meaningless to execute the measurement mode. By setting a threshold value for the SOC, useless data is not acquired, so that data communication charges can be saved. Furthermore, even if the measurement mode is being executed, the management server 14 may stop the execution of the measurement mode if it is meaningless as described above. Furthermore, when the execution of the measurement mode is stopped, the management server 14 may instruct the charging / discharging device 12 to perform charging or discharging in the normal mode. This allows the management server 14 to instruct whether or not to execute the measurement mode. Furthermore, when the charging / discharging device 12 stops charging at an unintended timing, the management server 14 can appropriately instruct the suspension of the measurement mode.

[0094] FIG. 6 is a diagram showing the detection results of the voltage V, the current I, and the temperature T acquired by the acquisition unit 46 (see FIG. 2).

[0095] 6, the estimation unit 82 estimates the internal resistance value R of the battery 18, which is a degree of correlation with the deterioration of the battery 18. The internal resistance value R is calculated by the following formula (1). R = ΔV / ΔI (1)

[0096] ΔV is the voltage difference between two voltages V at different times. Also, ΔI is the current difference between two currents I at different times.

[0097] For example, when the voltage V and current I at t=122 seconds and the voltage V and current I at t=182 seconds are used, R≈2.78Ω.

[0098] The estimation unit 82 may perform temperature correction on the voltage V and the current I, and estimate the internal resistance value R using the voltage V and the current I after temperature correction.

[0099] Fig. 7A shows the relationship between ΔV and ΔI in the period from time t0 to time t14 in Fig. 4. In this period, ΔV and ΔI each have a substantially constant value regardless of the passage of time.

[0100] Fig. 7B shows the relationship between ΔV and ΔI in the period from time t14 to time t4 in Fig. 4. In this period, the current I decreases stepwise, so that ΔV and ΔI each change with the passage of time.

[0101] 8 is a diagram showing the relationship between the SOC of the battery 18 and the internal resistance value R. The SOC is estimated based on the voltage V of the battery 18.

[0102] The estimation unit 82 (see FIG. 2) also estimates the deterioration level SOH, which is calculated by the following formula (2) or (3). SOH = {(battery capacity at time of use) / (initial battery capacity)}×100 (2) SOH = {(internal resistance of the battery at the time of use) / (internal resistance value of battery when first used)}×100 (3)

[0103] The capacity of the battery 18 is measured in units of A·h (amount of charge) and W·h (amount of work).

[0104] Fig. 9 shows the relationship between the resistance value under standard conditions and the resistance increase rate. The resistance value under standard conditions is the resistance value when the internal resistance value R of the battery 18 estimated by the estimation unit 82 (see Fig. 2) is converted to the standard conditions of 50% SOC and a temperature of 25°C. The resistance increase rate indicates the increase rate of the resistance value from the start date of measurement in the measurement mode (April 1 in Fig. 9). The resistance increase rate corresponds to the degree of deterioration SOH.

[0105] The determination unit 84 determines that the battery 18 should be collected when the resistance increase rate reaches 100% on December 1, for example. Collecting the battery 18 means removing the battery 18 from the battery 18 used in a mobile body such as a two-wheeled vehicle or a four-wheeled vehicle. Therefore, the collected battery 18 is used as a battery for an object other than a mobile body. For example, the collected battery 18 is used as a battery for home appliances.

[0106] Next, the operation of the charging / discharging system 10 according to this embodiment will be described with reference to Fig. 10 to Fig. 12. Here, the case where charging / discharging processing is performed on the battery 18 (see Figs. 1 and 2) in the measurement mode will be mainly described.

[0107] In step S1, the user returns the battery 18 to the first charging / discharging device 20. As a result, the battery 18 is accommodated in the slot 26 of the first charging / discharging device 20.

[0108] In step S2, in the battery 18 accommodated in the slot 26, the voltage detection unit 38 starts detecting the voltage V of the battery 18. The current detection unit 40 starts detecting the current I flowing through the battery 18. The temperature detection unit 42 starts detecting the temperature T of the battery 18. As a result, the detection results of the voltage detection unit 38, the current detection unit 40, and the temperature detection unit 42 are sequentially output from the battery 18 to the first charge / discharge device 20.

[0109] The acquisition unit 46 of the first charging / discharging device 20 sequentially acquires each detection result from the battery 18. The communication unit 34 sequentially transmits each detection result acquired by the acquisition unit 46 to the management server 14.

[0110] Thereafter, in step S3, the battery 18 is lent from the first charging / discharging device 20.

[0111] In step S4, the acquisition unit 62 of the management server 14 starts acquiring each detection result from the first charging / discharging device 20. The counting unit 64 counts the number of times the battery 18 has been exchanged since the previous execution of the measurement mode to the present time. The number of times of exchange is the number of times the battery 18 has been lent out and returned from the first charging / discharging device 20 or the second charging / discharging device 22.

[0112] In step S5, the determination unit 66 determines whether the number of times the battery 18 has been replaced is equal to or greater than a threshold value. This threshold value may be changed according to the degree of deterioration of the battery 18. For example, for a battery 18 that is about to be collected, the threshold value may be set so that the measurement mode is executed frequently.

[0113] If the number of replacements is equal to or greater than the threshold value (step S5: YES), the determination unit 66 determines that the measurement mode should be executed for the battery 18. After that, the calculation unit 54 proceeds to step S6.

[0114] In step S6, the list update unit 68 receives the positive determination result from the determination unit 66 and changes the flag of the battery 18 from 0 to 1 in the battery list stored in the storage unit 58. In response to the flag of the battery list being changed to 1, the setting change unit 70 changes the content of the charge / discharge setting information stored in the storage unit 58. In this case, the setting change unit 70 changes at least one of a plurality of parameters of the battery 18 included in the charge / discharge setting information. The setting change unit 70 changes the parameter based on at least one of the type, model, current state, degree of correlation with current deterioration, and past usage of the battery 18.

[0115] In step S7, the communication unit 34 transmits the battery list and the charge / discharge setting information stored in the storage unit 58 to the first charge / discharge device 20 and the second charge / discharge device 22.

[0116] As a result, in step S8, the communication unit 34 of the first charge / discharge device 20 receives the battery list and the charge / discharge setting information. The battery list and the charge / discharge setting information stored in the memory unit 36 ​​are updated to the received battery list and charge / discharge setting information.

[0117] In step S9, the communication unit 34 of the second charge / discharge device 22 receives the battery list and the charge / discharge setting information. The battery list and the charge / discharge setting information stored in the storage unit 36 ​​are updated to the received battery list and charge / discharge setting information.

[0118] In step S5, if the number of replacements of battery 18 has not reached the threshold value (step S5: NO), judgment unit 66 judges that it is not necessary to execute the measurement mode for battery 18. In this case, calculation unit 54 skips the processes of steps S6 and S7. That is, calculation unit 54 does not change the contents of the battery list and charge / discharge setting information stored in memory unit 58. In addition, communication unit 56 does not transmit the battery list and charge / discharge setting information to first charge / discharge device 20 and second charge / discharge device 22.

[0119] Thereafter, in step S10, the user returns the battery 18 to the second charging / discharging device 22. As a result, the battery 18 is accommodated in the slot 26 of the second charging / discharging device 22.

[0120] In step S11 of Fig. 11, the charge / discharge processing unit 48 (see Fig. 2) of the second charge / discharge device 22 (see Fig. 1) determines whether the current time is N hours before the closing time of the second charge / discharge device 22. Note that N can be set appropriately.

[0121] If the current time is N hours before the closing time (step S11: YES), the charge / discharge processing unit 48 determines that the measurement mode can be executed. After that, the calculation unit 32 of the second charge / discharge device 22 proceeds to step S12.

[0122] In step S12, the charge / discharge processing unit 48 refers to the battery list stored in the storage unit 36 ​​and determines whether the flag for the battery 18 is 1 or not.

[0123] If the flag is 1 (step S12: YES), the charge / discharge processing unit 48 determines that it is necessary to perform charge / discharge processing in the measurement mode on the battery 18. Thereafter, the calculation unit 32 of the second charge / discharge device 22 proceeds to step S13.

[0124] In step S13, the charge / discharge processing unit 48 executes a charge / discharge process in the measurement mode for the battery 18. In this case, the charge / discharge processing unit 48 sets various parameters related to charging / discharging of the battery 18 based on the charge / discharge setting information stored in the storage unit 36, and then executes a charge / discharge process in the measurement mode. As a result, the detection results of the voltage V, the current I, and the temperature T are sequentially output from the battery 18 to the second charge / discharge device 22. The acquisition unit 46 acquires the detection results of the voltage V, the current I, and the temperature T at each timing shown in FIG. 5. The acquired detection results are sequentially stored in the storage unit 36.

[0125] When the charge / discharge process in the measurement mode is completed, in step S14, the communication unit 34 transmits each detection result stored in the memory unit 36 ​​to the management server 14. That is, the communication unit 34 transmits all the detection results stored in the memory unit 36 ​​by one cycle of the charge / discharge process in the measurement mode to the management server 14.

[0126] If the current time is not N hours before the business closing time in step S11 (step S11: NO), the charge / discharge processing unit 48 determines that the situation allows charge / discharge processing in the normal mode. If the flag in the battery list is 0 in step S12 (step S12: NO), the charge / discharge processing unit 48 determines that it is not necessary to perform charge / discharge processing in the measurement mode for the battery 18.

[0127] If the determination result in step S11 or step S12 is negative, in step S15, the charge / discharge processing unit 48 determines not to execute the charge / discharge processing in the measurement mode. As a result, in the calculation unit 32, the processes in steps S13 and S14 are skipped.

[0128] After step S14 or step S15, the battery 18 is lent from the second charge / discharge device 22 in step S16.

[0129] In step S17, the determining unit 66 of the management server 14 determines whether the acquiring unit 62 has acquired each detection result of the battery 18 or not.

[0130] If the acquisition unit 62 acquires each detection result of the battery 18 and each acquired detection result is stored in the storage unit 58 (step S17: YES), in step S18, the determination unit 66 determines that the charging / discharging process in the measurement mode has been completed, and therefore changes the flag for the battery 18 in the battery list from 1 to 0. In response to the determination result of the determination unit 66, the list update unit 68 updates the flag for the battery 18 in the battery list stored in the storage unit 58 to 0.

[0131] In step S19, communication unit 56 transmits the battery list stored in storage unit 58 to first charging / discharging device 20 and second charging / discharging device 22.

[0132] As a result, in step S20, the communication unit 34 of the first charging / discharging device 20 receives the battery list. The battery list stored in the memory unit 36 ​​is updated with the contents of the received battery list.

[0133] Also, in step S21, the communication unit 34 of the second charging / discharging device 22 receives the battery list. The battery list stored in the storage unit 36 ​​is updated with the contents of the received battery list.

[0134] As a result, when the battery 18 is returned and stored in the first charging / discharging device 20 or the second charging / discharging device 22, the charging / discharging process in the normal mode is performed on the battery 18. Therefore, in step S18, the setting change unit 70 does not need to update the charging / discharging setting information.

[0135] In step S22 of FIG. 12, the communication unit 56 (see FIG. 2) transmits each detection result of the battery 18 stored in the storage unit 58 to the analysis server 16.

[0136] In step S23, if the acquisition unit 80 of the analysis server 16 acquires each detection result of the battery 18 (step S23: YES), the calculation unit 72 proceeds to step S24.

[0137] In step S24, the estimation unit 82 estimates the internal resistance value R of the battery 18 based on the acquisition results of the voltage V and the current I acquired by the acquisition unit 80. In addition, the estimation unit 82 estimates the degree of deterioration SOH of the battery 18 based on the internal resistance value R or the acquisition results of the voltage V and the current I acquired by the acquisition unit 46.

[0138] In step S25, the determination unit 84 determines whether or not the battery 18 should be withdrawn, using the internal resistance value R or the resistance increase rate based on the degree of deterioration SOH.

[0139] For example, when the resistance increase rate reaches 100% (step S25: YES), the determination unit 84 determines that the battery 18 should be collected. In the next step S26, the determination unit 84 outputs an instruction to collect the battery 18 to the communication unit 74. The communication unit 74 transmits the instruction content of the determination unit 84 to the first charging / discharging device 20 and the second charging / discharging device 22 (see FIG. 1 ) via the management server 14. The first charging / discharging device 20 and the second charging / discharging device 22 store the instruction content received by the communication unit 34 in the storage unit 36. Thereby, when the user returns the battery 18 to the first charging / discharging device 20 or the second charging / discharging device 22, the first charging / discharging device 20 or the second charging / discharging device 22 can collect the battery 18 based on the instruction content stored in the storage unit 36.

[0140] In step S25, if the resistance increase rate has not reached 100% (step S25: NO), the determination unit 84 determines that the battery 18 is unnecessary. In this case, the process of step S26 is skipped.

[0141] In step S11, it is basically desirable to execute the measurement mode outside business hours. However, in the case of battery 18 for which charging in normal mode would not be completed within business hours, the measurement mode may be entered. In addition, outside business hours is, for example, the time period from midnight to 5:00 a.m. Also, if charging in normal mode takes, for example, three hours, charging in measurement mode takes three and a half hours. In this case, in step S11, the measurement mode may be executed if it is after 9:30 p.m.

[0142] As described above, in this embodiment, it is possible to appropriately change the range for acquiring the SOC or the voltage V in order to acquire the internal resistance value R or the degree of deterioration SOH in accordance with the characteristics of the battery 18. This makes it possible to more accurately estimate the internal resistance value R or the degree of deterioration SOH.

[0143] That is, in this embodiment, the estimation of the internal resistance value R or the deterioration level SOH can be performed for a wide range of voltage V. Moreover, it is possible to measure the voltage V after putting the battery in a resting state, rather than changing the voltage V sharply. Furthermore, it is also possible to measure the voltage V while charging the battery 18 by flowing a constant current value Ic. Moreover, it is also possible to estimate the internal resistance value R or the deterioration level SOH in accordance with changes in the battery 18. Moreover, since each detection result is obtained after the measurement mode is executed, it is possible to save on data communication charges. That is, by setting a threshold value or the like for the voltage V or SOC, it is possible to avoid obtaining unnecessary data, and therefore it is possible to save on data communication charges. Furthermore, it is possible to appropriately change the charging time and the resting time from the management server 14.

[0144] In this manner, in this embodiment, the internal resistance value R or the degree of degradation SOH, which is an index of degradation of the battery 18, can be estimated while minimizing increases in charging time while monitoring the state of service of the battery 18 by the charging / discharging device 12 from the management server 14. This makes it possible to grasp changes in the internal resistance value R or the degree of degradation SOH for each SOC. In addition, since the management server 14 can change various settings (charge / discharge setting information) related to charging or discharging the battery 18, it is possible to estimate the internal resistance value R or the degree of degradation SOH even if the type of battery 18 is changed.

[0145] In the above explanation, the management server 14 and the analysis server 16 are separate entities, but the management server 14 and the analysis server 16 may be a single server.

[0146] In the above description, the analysis server 16 performs the estimation process of the internal resistance value R and the degree of deterioration SOH, and the determination process for the collection of the battery 18. In this embodiment, the estimation process and the determination process may be performed by the management server 14. Alternatively, the estimation process and the determination process may be performed by the charging / discharging device 12. Also, any one of the charging / discharging device 12, the management server 14, and the analysis server 16 may perform the estimation process, and the remaining device may perform the determination process.

[0147] Furthermore, in the above description, the battery list change process and the charge / discharge setting information change process are performed by the management server 14. In this embodiment, the charging / discharging device 12 or the analysis server 16 may perform the battery list change process and the charge / discharge setting information change process. Alternatively, any one of the charging / discharging device 12, the management server 14, and the analysis server 16 may perform the battery list change process, and the remaining device may perform the charge / discharge setting information change process.

[0148] In the above description, the battery list and the charge / discharge setting information are transmitted from the management server 14 to the charge / discharge device 12. In this embodiment, the charge / discharge device 12 may inquire of the management server 14 about whether or not to execute the measurement mode. In this case, when the management server 14 instructs the execution of the measurement mode, the charge / discharge device 12 may execute the measurement mode. At this time, the charge / discharge device 12 may execute the measurement mode based on the charge / discharge setting information stored in the storage unit 36. Alternatively, when the management server 14 instructs the execution of the measurement mode, the charge / discharge device 12 may receive the charge / discharge setting information from the management server 14, and execute the measurement mode based on the received charge / discharge setting information.

[0149] The invention that can be understood from the above-described embodiments will be described below.

[0150] A first aspect of the present invention is an estimation method for estimating a degree of correlation with deterioration of an energy storage device (18), the estimation method having a charge / discharge step (S13) of charging or discharging the energy storage device, a pause step (S13) of pausing charging or discharging in the charge / discharge step, an acquisition step (S13, S17, S23) of acquiring at least one of a first voltage (V1) which is a voltage (V) of the energy storage device in the charge / discharge step and a second voltage (V2) which is a voltage of the energy storage device in the pause step, and an estimation step (S24) of estimating the degree of correlation with deterioration (R, SOH) based on at least one of the first voltage and the second voltage.

[0151] According to the present invention, it is possible to accurately estimate the degree of correlation with deterioration of the power storage device.

[0152] In a first aspect of the present invention, when the time until the electric energy (SOC) or voltage of the storage device changes from a first amount (Vt0) to a second amount (Vf) is defined as one cycle, the charge / discharge step and the pause step are alternately repeated within the one cycle, and the acquisition step acquires the second voltage in each of the multiple pause steps, and in the one cycle, at least one of the number of transitions from the charge / discharge step to the pause step, the threshold electric energy or threshold voltage (Vt1, Vt2, Vt3, Vt4, Vt5) when transitioning from the charge / discharge step to the pause step, the duration (To) of each of the multiple pause steps, and the acquisition mode of the multiple second voltages in the acquisition step can be changed.

[0153] This makes it possible to appropriately acquire the first voltage and the second voltage even if the type of the power storage device is changed.

[0154] In a first aspect of the present invention, at least one of the number of times, the threshold energy or threshold voltage, the duration, and the acquisition mode of the multiple second voltages can be changed based on at least one of the type, model, current state, degree of correlation with the current deterioration, and past usage mode of the storage device.

[0155] This makes it possible to appropriately obtain the first voltage and the second voltage depending on the type of the power storage device, etc.

[0156] In the first aspect of the present invention, the multiple acquisition modes of the second voltage include at least one of a period (To), a number of times, a frequency, and a cycle (Tn, Tot) for acquiring the second voltage.

[0157] This makes it possible to properly obtain the second voltage.

[0158] In a first aspect of the present invention, in the acquisition step, the second voltage is acquired at a first time (To-Tos) from the start of the pause step to a first point in time that is a certain time after the start of the pause step, and at a second time (Tos) from the first point in time to the start of the charge / discharge step, which is the end of the pause step, and the second time is shorter than the first time, and a first period (Tn), which is the period for acquiring the second voltage at the first time, is longer than a second period (Tot), which is the period for acquiring the second voltage at the second time.

[0159] This makes it possible to precisely obtain the second voltage during the time period immediately prior to the start of the charge / discharge step.

[0160] In a first aspect of the present invention, the charging / discharging step and the pausing step are alternately and repeatedly executed, and in the acquisition step, the first voltage in each of the multiple charging / discharging steps is acquired, and further, the acquisition manner of the multiple first voltages is changeable.

[0161] This makes it possible to properly acquire the first voltage.

[0162] In a first aspect of the present invention, in the acquisition step, the acquisition manner of the multiple first voltages can be changed based on at least one of the type, model, current state, degree of correlation with the current deterioration, and past usage manner of the storage device.

[0163] This makes it possible to appropriately obtain the first voltage depending on the type of the power storage device, etc.

[0164] In the first aspect of the present invention, the multiple acquisition modes of the first voltage include at least one of a period (Tc), a number of times, a frequency, and a cycle (Tct, Tn) for acquiring the first voltage.

[0165] This makes it possible to properly acquire the first voltage.

[0166] In a first aspect of the present invention, in the acquisition step, the first voltage is acquired during a third time (Tcs) from the start of the charge / discharge step to a second time point a certain time has elapsed, and during a fourth time (Tc-Tcs) from the second time point to the start of the pause step which is the end of the charge / discharge step, and the third time is shorter than the fourth time, and a third cycle (Tct), which is the period for acquiring the first voltage during the third time, is shorter than a fourth cycle (Tn), which is the period for acquiring the first voltage during the fourth time.

[0167] This makes it possible to obtain the first voltage in detail during the time period immediately after the start of the charge / discharge step.

[0168] In a first aspect of the present invention, when the time it takes for the amount of power or voltage of the storage device to change from a first amount to a second amount is defined as one cycle, the charging / discharging step and the pausing step are alternately and repeatedly executed, and the acquisition step acquires the first voltage in each of a plurality of the charging / discharging steps and the second voltage in each of a plurality of the pausing steps collectively after the charging / discharging step and the pausing step have been alternately and repeatedly executed within the one cycle.

[0169] This eliminates the need to sequentially obtain data, making it possible to save on data communication charges, prevent unnecessary data transmission, and reduce communication and processing loads.

[0170] In a first aspect of the present invention, in the estimating step, a degree of correlation with the deterioration is estimated based on a difference between the first voltage and the second voltage.

[0171] This makes it possible to more accurately estimate the degree of correlation with the deterioration of the power storage device.

[0172] In a first aspect of the present invention, the degree of correlation with deterioration is an internal resistance value (R) or a degree of deterioration (SOH) of the power storage device.

[0173] This makes it possible to easily estimate the degree of correlation with the deterioration of the power storage device.

[0174] In the first aspect of the present invention, in the charging / discharging step, a constant current (Ic) is caused to flow to the power storage device to charge it, or a constant current is caused to flow from the power storage device to discharge it.

[0175] This allows the charging and discharging processes to be carried out easily.

[0176] A second aspect of the present invention is a program for causing a computer (16) to execute the estimation method of the first aspect.

[0177] The present invention also provides the same effects as the first aspect.

[0178] A third aspect of the present invention is a storage medium (76) that stores the program of the second aspect.

[0179] The present invention also provides the same effects as the first aspect.

[0180] A fourth aspect of the present invention is an estimation device (16) for estimating a degree of correlation with deterioration of an energy storage device, the estimation device comprising: an acquisition unit (80) that acquires at least one of a first voltage which is the voltage of the energy storage device when the energy storage device is charged or discharged, and a second voltage which is the voltage of the energy storage device when charging or discharging of the energy storage device is suspended; and an estimation unit (82) that estimates the degree of correlation with the deterioration based on the one of the voltages acquired by the acquisition unit.

[0181] The present invention also provides the same effects as the first aspect.

[0182] A fifth aspect of the present invention is a charge / discharge system (10) including a charge / discharge device (12, 20, 22) that charges or discharges an electricity storage device, and the estimation device of the fourth aspect.

[0183] The present invention also provides the same effects as the first aspect.

[0184] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention. [Explanation of symbols]

[0185] 10...Charging / discharging system 12...Charging / discharging device 16...Analysis server (estimation device, computer) 18... battery (electricity storage device) 20... first charge / discharge device (charge / discharge device) 22…Second charging / discharging device (charging / discharging device) 36, 58, 76... Storage section (storage medium) 46, 62, 80... Acquisition section 82…Estimation part

Claims

1. An estimation method for estimating the degree of correlation with the deterioration of a power storage device, comprising: a charge / discharge step of charging or discharging the power storage device; a pause step of pausing the charging or discharging in the charge / discharge step; an acquisition step of acquiring at least one of a first voltage that is the voltage of the power storage device in the charge / discharge step and a second voltage that is the voltage of the power storage device in the pause step; an estimation step of estimating the degree of correlation with the deterioration based on at least one of the first voltage and the second voltage; The estimation method comprising the above steps.

2. In the estimation method according to Claim 1, when the time until the power amount or voltage of the power storage device changes from a first amount to a second amount is taken as one cycle, the charge / discharge step and the pause step are alternately and repeatedly executed within the one cycle, in the acquisition step, the second voltage in each of a plurality of the pause steps is acquired, in the one cycle, at least one of the number of transitions from the charge / discharge step to the pause step, a threshold power amount or a threshold voltage when transitioning from the charge / discharge step to the pause step, the duration of each of the plurality of pause steps, and the acquisition mode of the plurality of second voltages in the acquisition step can be changed.

3. In the estimation method according to Claim 2, based on at least one of the type, model, current state, current degree of correlation with the deterioration, and past usage pattern of the power storage device, at least one of the number of times, the threshold power amount or the threshold voltage, the duration, and the acquisition mode of the plurality of second voltages can be changed.

4. In the estimation method according to Claim 2 or 3, the acquisition modes of the plurality of second voltages include at least one of the period, number of times, frequency, and cycle for acquiring the second voltage.

5. In the estimation method according to Claim 4, in the acquisition step, the second voltage is acquired at a first time from the start time of the pause step to a first point in time after a certain time has elapsed and at a second time from the first point in time to the start time of the charge / discharge step which is the end time of the pause step, the second time is shorter than the first time. An estimation method in which a first period, which is the period for acquiring the second voltage at the first time, is longer than a second period, which is the period for acquiring the second voltage at the second time. **Claim 6** In the estimation method according to any one of Claims 1 to 3, the charging / discharging step and the rest step are alternately and repeatedly executed, and in the acquisition step, the first voltage in each of a plurality of the charging / discharging steps is acquired, and furthermore, the acquisition mode of the plurality of first voltages can be changed. **Claim 7** In the estimation method according to Claim 6, in the acquisition step, based on at least any one of the type, model, current state, degree of correlation with the current deterioration, and past usage mode of the power storage device, the acquisition mode of the plurality of first voltages can be changed. **Claim 8** In the estimation method according to Claim 6, the acquisition modes of the plurality of first voltages include at least any one of the period, number of times, frequency, and cycle for acquiring the first voltage. **Claim 9** In the estimation method according to Claim 8, in the acquisition step, the first voltage is acquired at a third time from the start point of the charging / discharging step to a second time point after a certain time has elapsed, and at a fourth time from the second time point to the start point of the rest step, which is the end point of the charging / discharging step, the third time is shorter than the fourth time, and a third cycle, which is the period for acquiring the first voltage at the third time, is shorter than a fourth cycle, which is the period for acquiring the first voltage at the fourth time. **Claim 10** In the estimation method according to any one of Claims 1 to 3, when one cycle is defined as the time until the amount of power or voltage of the power storage device changes from a first amount to a second amount, the charging / discharging step and the rest step are alternately and repeatedly executed, and in the acquisition step, after the charging / discharging step and the rest step are alternately and repeatedly executed within the one cycle, the first voltage in each of a plurality of the charging / discharging steps and the second voltage in each of a plurality of the rest steps are collectively acquired. **Claim 11** In the estimation method according to any one of Claims 1 to 3, In the estimation step, an estimation method for estimating the degree of correlation with the deterioration based on the difference between the first voltage and the second voltage.

12. In the estimation method according to any one of Claims 1 to 3, the degree of correlation with the deterioration is the internal resistance value or the degree of deterioration of the power storage device.

13. In the estimation method according to any one of Claims 1 to 3, in the charge / discharge step, the power storage device is charged by passing a constant current through the power storage device, or discharged by passing a constant current from the power storage device.

14. A program for causing a computer to execute the estimation method according to any one of Claims 1 to 3.

15. A storage medium storing the program according to Claim 14.

16. An estimation device for estimating the degree of correlation with the deterioration of a power storage device, an acquisition unit that acquires at least one of a first voltage that is the voltage of the power storage device when the power storage device is charged or discharged and a second voltage that is the voltage of the power storage device when the charging or discharging of the power storage device is paused; an estimation unit that estimates the degree of correlation with the deterioration based on the one voltage acquired by the acquisition unit; An estimation device comprising:

17. A charge / discharge system comprising a charge / discharge device that charges or discharges a power storage device and the estimation device according to Claim 16.

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