Battery storage system and battery maintenance support method

Abstract

To provide a storage battery system capable of determining a decrease in cooling capacity without acquiring a huge amount of pre-evaluation data.SOLUTION: A storage battery system capable of supporting maintenance by estimating a state of a storage battery provided with cooling capacity for a movable body includes a battery temperature recording part for detecting and recording a maximum arrival temperature Tmax on a daily basis by a temperature sensor attached to the storage battery, an environmental temperature recording part for detecting and recording a maximum arrival value Tamb, max of an environmental temperature Tamb in a time zone dating back from a time when the maximum arrival temperature Tmax is detected to a service start time of the day, and a maintenance support information table for storing measures policies associated with the state of the storage battery, determines the degree of a decrease in cooling capacity on the basis of the maximum arrival temperature Tmax, and the maximum arrival value Tamb, max of the environmental temperature Tam, estimates the state of the storage battery on the basis of a determination result of the decrease on the capacity, and can output information selected from the maintenance support information table on the basis of the estimated state of the storage battery.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a storage battery system capable of determining the health of a storage battery system having a cooling capacity, and a storage battery maintenance support method. [Background technology]

[0002] To operate a battery storage system safely and securely, it is necessary to manage the battery temperature within an appropriate range. Therefore, it is important to have technology for operating the battery storage system with appropriate maintenance according to its condition.

[0003] In a battery system equipped with a cooling mechanism, the maximum temperature that the battery reaches is determined by a combination of factors, such as the deterioration rate and internal resistance of the battery, the outside temperature, the cooling capacity and its rate of decline, the load pattern (power or current), etc. Therefore, when the battery overheats beyond the specifications, it is necessary to separate the causes and identify the main cause, and then implement appropriate measures according to the main cause at the appropriate time.

[0004] Therefore, it is particularly important to detect the cooling capacity and its rate of decline among the factors, and there is a demand for technology that can detect this without the need for additional flowmeter sensors, etc. Patent Document 1 discloses a technology that manages storage battery systems, the main use of which is automobiles, and calculates the amount of clogging in a filter that prevents dust from entering the storage battery system as an index related to the rate of decline in the cooling capacity of a cooling mechanism that uses an outside air intake fan, and determines the timing for filter replacement.

[0005] Furthermore, Patent Document 2 discloses a battery monitoring device and a battery system, which lists various index values ​​for objectively evaluating the state of a storage battery, and describes that the rate of increase in internal resistance due to deterioration of a battery cell, SOHR (hereinafter simply referred to as "SOHR"), is calculated and used as a battery management index. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2016-177971 A [Patent Document 2] Patent Publication No. 2021-44145 Summary of the Invention [Problem to be solved by the invention]

[0007] The cooling system for the on-board battery pack in Patent Document 1 is used under completely different conditions depending on the behavioral patterns of the vehicle user to which it is applied. Therefore, in order to realize the calculation of the cooling capacity decline rate estimation, it is necessary to obtain a huge amount of pre-evaluation data for parameter identification.

[0008] In response to this, the present inventors obtained the SOHR as a storage battery management index disclosed in Patent Document 2, and examined whether the SOHR could be applied to simplify the estimation of the cooling capacity decline rate as described in Patent Document 1. The present invention has been made in view of the above problems, and has an object to provide a storage battery system that can determine the decline in cooling capacity without acquiring a huge amount of advance evaluation data. [Means for solving the problem]

[0009] The present invention, which solves the above-mentioned problems, is a storage battery system capable of estimating the state of a storage battery equipped with cooling capacity for a mobile body and supporting maintenance, and includes a battery temperature recording unit that detects and records a maximum reached temperature Tmax on a daily basis using a temperature sensor attached to the storage battery, an environmental temperature recording unit that detects and records a maximum reached value Tamb,max of the environmental temperature Tamb in the time period going back from the time when the maximum reached temperature Tmax was detected to the start time of operation on that day, and a maintenance support information table in which countermeasures policies corresponding to the state of the storage battery are stored, and the system determines the degree of deterioration in cooling capacity based on the maximum reached temperature Tmax and the maximum reached value Tamb,max of the environmental temperature Tamb, estimates the state of the storage battery based on the determination result of the capacity decline, and is capable of outputting information selected from the maintenance support information table based on the estimated state of the storage battery. Effect of the Invention

[0010] According to the present invention, it is possible to provide a storage battery system capable of determining a decrease in cooling capacity without acquiring a large amount of pre-evaluation data. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0011] [Figure 1] 1 is a functional block diagram for explaining the configuration of a railway storage battery system (hereinafter also referred to as "this system") according to an embodiment of the present invention. [Diagram 2] 2 is a graph showing a two-dimensional area used to determine a decrease in cooling capacity in the system of FIG. 1. [Diagram 3] 2 is a graph showing the correlation between the degree of battery deterioration and SOHR in the system of FIG. 1. [Figure 4] This is a list of countermeasure policies that are determined based on the results of classification judgment according to the positions where the cause judgment index and the environmental temperature Tamb are plotted on the graph of FIG. [Diagram 5] 1 is a flowchart showing an outline of a battery maintenance support method according to an embodiment of the present invention (hereinafter also referred to as "the method"). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] <Summary> Hereinafter, the present system 20 (FIG. 1) will be described with reference to FIGS. 1 to 4. The present system 20 exemplifies the overall cooling capacity including a storage battery 1 whose main application is railways and an associated cooling mechanism 2 as an object to be managed. The present system 20 determines the deterioration of the cooling capacity by utilizing the characteristic that a patterned load is repeated according to a railway operation schedule. As a result, the present system 20 determines the deterioration of the cooling capacity without acquiring a huge amount of pre-evaluation data related to it.

[0013] Based on the result of the determination, the system 20 provides the execution body with information on countermeasures to eliminate the malfunction of the storage battery system 20. The execution body prompts an entity (decision department) or a maintenance worker to execute a countermeasure policy based on the information received from the system 20.

[0014] The subject refers to a human driver or driving command, as well as a computer such as an operation management system or an automatic driving system. A maintenance worker, etc. refers to a person who can perform maintenance work such as replacing the storage battery 1. In addition, this system 20 identifies parts to be replaced, notifies the user of the arrival of the end of the life that requires replacement, and issues information to encourage the replacement of the parts.

[0015] <Configuration> Fig. 1 is a functional block diagram for explaining the configuration of this system 20. In Fig. 1, the battery system 20 is composed of a battery group (hereinafter also simply referred to as a "storage battery") 1, a cooling mechanism 2, a battery management device 3, a battery current recording unit 4, a battery voltage recording unit 5, a battery temperature recording unit 6, and an environmental temperature recording unit 7.

[0016] Examples of the storage battery 1 include, but are not limited to, a lithium ion battery, a lead storage battery, a nickel metal hydride battery, a nickel cadmium battery, etc. If the cooling mechanism 2 is of a forced air cooling type (not shown), it is exemplified by a heat dissipation fin connected to the can of the storage battery 1, which is a heat generating body, in a thermally conductive manner, and a blower fan that sends air to the fin. Other examples include a liquid cooling type (not shown). Regardless of the cooling type of the cooling mechanism 2, it is possible to determine the decrease in cooling capacity by combining it with the present system 20.

[0017] The battery management device 3 is composed of a resistivity calculation unit 8, a maximum reached temperature extraction unit 9, a factor determination index calculation unit 10, and a factor determination unit 11. The resistivity calculation unit 8 calculates the resistivity. Methods for calculating the resistivity include, but are not limited to, a method of dividing a resistance value calculated from the ratio of a current change to a voltage change by a reference resistance value, and a Kalman filter. The Kalman filter is used to estimate a quantity that changes over time from observations with discrete errors.

[0018] The storage battery 1 is configured as a battery group (also called a battery pack) by connecting an appropriate number of battery cells in series and parallel. The state detection device may obtain the rate of increase in the internal resistance value SOHR of the entire battery group (storage battery) 1 based on the rate of increase in the internal resistance value SOHR of each battery cell that configures the battery group (storage battery) 1.

[0019] As an example, this SOHR can be calculated by the following formula (1), but it can also be calculated by other methods. In the following formula (1), Rc is the current internal resistance value of the battery cell, and Ro is the internal resistance value of the battery cell when it was first used. SOHR = 100 × (Rc / Ro) (1)

[0020] The maximum temperature extraction unit 9 extracts the maximum battery temperature Tmax and the maximum outside air temperature Tamb,max during daily train operation. The factor determination index calculation unit 10 calculates the cooling capacity decrease determination index using the resistivity, the maximum battery temperature Tmax, and the maximum outside air temperature Tamb,max as shown in the following formula (2). (Tmax-Tamb,max) / SOHR (2)

[0021] The factor determination unit 11 determines whether or not the cooling capacity has decreased by using the cooling capacity decrease determination index and the maximum outside air temperature Tamb,max. The details of the determination method will be described below with reference to Figs.

[0022] Fig. 2 is a graph showing a two-dimensional area used to determine the cooling capacity decrease in the system 20 of Fig. 1. In the graph of Fig. 2, the horizontal axis is the outside air temperature Tamb [°C], and the vertical axis is the cooling capacity decrease determination index, which is shown in the following formula (3). (Tmax-Tamb) / SOHR=ΔT / SOHR[K] (3)

[0023] In the graph of Figure 2, the threshold boundary is shown by a diagonal dashed line slanting downward to the right. If the maximum temperature reached Tmax [℃] and the maximum outside air temperature Tamb,max [℃] are plotted as daily observation values ​​on this graph, it is judged that there is no decrease in cooling capacity (No decrease in cooling capacity) if it is below the threshold boundary, and that there is a decrease in cooling capacity (There is a decrease in cooling capacity) if it is above.

[0024] Fig. 3 is a graph showing the correlation between the rate of increase SOHR [%] of internal resistance due to deterioration of a battery cell and the degree of battery deterioration in the system 20 of Fig. 1. As shown in Fig. 3, a brand new battery cell has a small SOHR, whereas a deteriorated product that needs to be replaced has a large SOHR. This means that, as shown in the above formula (1), the current internal resistance Rc of the battery cell gradually increases with deterioration compared to the internal resistance Ro of the battery cell at the beginning of use.

[0025] Fig. 4 is a table showing countermeasure policies determined based on the results of classification judgment according to the positions of the factor judgment index ΔT / SOHR [K] of the above formula (2) and the environmental temperature Tamb [°C] plotted on the graph in Fig. 2. This table shows, from the left as horizontal items, temperature and countermeasure policies, and, from the top as vertical items, shows, from the top as no temperature deviation (suitable temperature), SOHR rise, decreased cooling capacity, outside temperature rise (rare hot day), and disturbance of operation schedule.

[0026] In Fig. 4, the temperature indicates whether the position where the daily observed value is plotted on the graph in Fig. 2 is above or below the boundary line that is the threshold. The countermeasure policy further specifies whether the countermeasure is battery replacement, cooling replacement, or control replacement. According to the present system 20, it is particularly important to detect the cooling capacity and its rate of decline among the factors, but this can be detected without additional installation of a flow meter sensor or the like.

[0027] As described above, based on the result of categorizing the plot position according to the position on the graph in Figure 2, the countermeasure policy shown by O, X, and △ in the table in Figure 4 is decided. O means replacement is not necessary (Unnecessary), and × means replacement is necessary (Necessary). In the case of △, replacement is required only when the SOHR [%] value is greater than a specified value. Therefore, △ means that it is temporarily required (Temporarily required).

[0028] The first row in Fig. 4 shows a case where there is no characteristic in the plot and no temperature deviation. In this case, a policy is shown in which none of the countermeasures of battery replacement, cooling replacement, and control replacement is required.

[0029] The second row in Figure 4 shows the case where there is no characteristic in the plot and SOHR is rising. In this case, regardless of the environmental temperature Tamb [℃], the battery needs to be replaced and a control exchange is temporarily required.

[0030] The third row in Figure 4 shows a case where the cooling capacity is reduced because many of the plotted positions are above the threshold boundary line. In this case, cooling replacement is required, and depending on SOHR, battery replacement is also required.

[0031] The fourth row in Fig. 4 shows the case where the plotted position is on the boundary line of the threshold and the outside temperature is rising. In this case, depending on the SOHR, a policy that requires either battery replacement or control exchange is shown.

[0032] The fifth row in Fig. 4 shows a case where the plotted position is only one point above the threshold boundary line, indicating a disruption in the schedule. In this case, the policy of requiring battery replacement is indicated depending on the SOHR.

[0033] <Operation> Fig. 5 is a flowchart showing an outline of the procedure of the present method. In this method, the present system 20 is used to estimate the state of the storage battery 1 equipped with a cooling capacity for a mobile body and to support maintenance through steps (S1 to S8) shown in Fig. 5. Note that, prior to step (S1), a user (installer, manager) of the present system 20 prepares a maintenance support information table in which countermeasure policies associated with the state of the storage battery 1 are stored and held so as to be freely readable. Step (S1) and subsequent steps are executed by the present system 20. The processing functions are realized by a computer (not shown) constituting the present system 20 executing a program stored in a memory.

[0034] A computer executing this method can freely read out a maintenance support information table that stores and holds information on countermeasure policies associated with the state of the storage battery 1 (S1). The system 20 detects and records the maximum temperature Tmax reached each day using a temperature sensor attached to the storage battery 1 (S2). The maintenance support information table has an amount of information on the order of that shown in FIG. 4, and does not need to contain a huge amount of pre-evaluation data, but rather a simple list. It is preferable that the maintenance support information be based on empirical rules (database) that objectively take into account the existing maintenance cycle, busy periods, weather, and other conditions, and thus allows for optimal judgment.

[0035] The system 20 detects and records the maximum value Tamb,max of the environmental temperature Tamb during the time period going back from the time when the maximum temperature Tmax was detected to the start of operation on the day (S3). The system 20 determines the decrease in cooling capacity based on the maximum temperature Tmax and the maximum value Tamb,max of the environmental temperature Tamb (S4).

[0036] The system 20 estimates the state of the storage battery 1 based on the determination result of the decrease in cooling capacity (S5). The system 20 outputs information selected from the maintenance support information table based on the estimated state of the storage battery 1 (S6).

[0037] In this method, the system 20 uses the SOHR calculated by the resistivity calculation unit 8 as a battery management index, and the degree of cooling capacity decline can be estimated by a simple calculation. As a result, this method makes it possible to determine the decline in cooling capacity without acquiring a huge amount of pre-evaluation data. In addition, existing sensors for measuring voltage, current, and temperature are sufficient, so the burden of adding them is unnecessary or small.

[0038] The system 20 calculates a limit cooling capacity deterioration index at which the maximum temperature of the storage battery 1 falls within an upper limit temperature (S7). In a part replacement timing prediction step (S8), the system 20 predicts and notifies the appropriate time for part replacement based on the current cooling capacity deterioration index and the predicted amount of cooling capacity deterioration due to operation.

[0039] In this method, the parts to be replaced are at least one of the storage battery 1 itself and the cooling mechanism parts. As to which parts are to be replaced, it is sufficient to follow the countermeasure policy determined in the manner shown in the table in FIG.

[0040] In this way, the system 20 can predict the cause and near-future outcome of the decline in cooling capacity. Therefore, the system 20 is effective by encouraging the operator or maintenance worker to take the most appropriate measure to eliminate the cause identified as either battery replacement, cooling (mechanical part) replacement, or control change shown in Fig. 4.

[0041] In the part replacement time prediction step (S8), the system 20 may notify the appropriate time for part replacement as the remaining number of possible runs until part replacement based on the predicted value of the cooling capacity decrease per day of operation. In other words, according to this method, it is possible to clearly notify the future replacement schedule for the part identified to eliminate the cause of the cooling capacity decrease, if operation is continued at the current operating frequency.

[0042] In the part replacement time prediction step (S8), the system 20 may calculate a limit cooling capacity deterioration index that can determine the deterioration of cooling capacity from the deterioration rate of the storage battery 1 and the operation information. The calculation result of this method can obtain information on the frequency of use of the managed object from the operation information, so that the degree of the deterioration of cooling capacity according to the frequency can be quantitatively determined. As a result, according to this method, it is possible to urge the operation entity or maintenance worker to replace parts at an appropriate time, not too early and not too late, before a failure caused by a defective part occurs.

[0043] In the part replacement time prediction step (S8), the system 20 may calculate a limit cooling capacity degradation index using information on weather conditions during the operation period. In this method, if the calculation result of the limit cooling capacity degradation index indicates overheating due to extreme heat, for example, information on appropriate countermeasures is issued.

[0044] In the part replacement timing prediction step (S8), the system 20 may use the regular maintenance plan and operation plan of the railway vehicle to notify the regular maintenance timing immediately before the predicted value of the cooling capacity deterioration index exceeds the limit cooling capacity deterioration index as the part replacement timing. In this way, it is possible to urge the operation body or maintenance workers to replace the part at an appropriate time, not too early and not too late, before a failure caused by a defective part occurs.

[0045] Based on the result of the determination, the system 20 provides information to an execution entity that can execute measures for the storage battery 1 under management and the associated cooling mechanism 2. The execution entity exerts its effectiveness by encouraging a subject (decision-making unit) or a maintenance worker to execute a countermeasure policy based on the information received from the system 20.

[0046] In the present system 20, the degree of cooling capacity degradation can be estimated by a simple calculation by using the SOHR calculated by the resistivity calculation unit 8 as a battery management index. As a result, the present system 20 can determine the cooling capacity degradation without acquiring a huge amount of pre-evaluation data.

[0047] The system 20 estimates the state of the storage battery 1 based on the determination result of the cooling capacity decrease, and can output maintenance support information selected from the maintenance support information table 11 based on the estimated state of the storage battery 1. This enables the system 20 to determine the cooling capacity decrease without acquiring a huge amount of pre-evaluation data related to it.

[0048] In other words, even if the maximum reached value Tamb,max of the environmental temperature Tamb detected during the operating hours of the day is high, if the maximum reached temperature Tmax of the storage battery 1 does not exceed the upper limit temperature, the cooling capacity is functioning sufficiently, so it can be considered that there is no decrease in cooling capacity.

[0049] In addition, when the maximum reached value Tamb,max of the environmental temperature Tamb is abnormally high, if the maximum reached temperature Tmax of the storage battery 1 also exceeds the upper limit temperature, this may be a natural phenomenon rather than a malfunction of the storage battery 1 and the storage battery system 20. If overheating occurs unavoidably on an unexpectedly hot day, it is determined that the operation of the managed railway vehicles should be suspended.

[0050] In other words, the cooling capacity of the storage battery 1 and the storage battery system 20 is designed to be just a little bit higher than the minimum required to ensure that the storage battery 1 does not exceed the upper limit temperature even in the heat of the day. Also, it is assumed that the design will not cause overheating so that the upper limit temperature will not be exceeded even on extremely hot days, not to mention when it is not hot.

[0051] Conversely, if the maximum reachable temperature Tmax of the storage battery 1 becomes abnormally high even though the maximum reachable value Tamb,max of the environmental temperature Tamb is not high, it is considered that at least either the storage battery 1 or the storage battery system 20 has malfunctioned and the cooling capacity has decreased to such an extent that it deviates from the standard.

[0052] In this case, the system 20 checks the maximum temperature Tmax of the storage battery 1 against at least one of the environmental temperature specifications (e.g., -15°C≦air temperature 50°C) and the heat resistance design (e.g., -20°C≦air temperature 55°C) of the railway vehicle to be managed. Depending on the check result, the system 20 determines that the failure occurred within the range of normal use defined in the specifications. In other words, it is a failure that should not occur, and urges the operation body or maintenance workers to take measures against the failure.

[0053] Based on technical information including such empirical rules, it is known that the cooling capacity of the storage battery 1 and the storage battery system 20 deteriorates over time even if they are designed to comply with product specifications at the time of manufacture. Therefore, the system 20 detects the cooling capacity at an early stage and outputs optimal maintenance information.

[0054] For this purpose, the present system 20 is capable of determining the decline in cooling capacity without acquiring a huge amount of pre-evaluation data. Furthermore, the present system 20 makes it possible to detect the cooling capacity and its decline rate, which are particularly important factors, using existing voltage, current, and temperature sensors without the need for additional flowmeter sensors or the like.

[0055] <Additional information> The present system 20 illustrated here is for use in railways, and has a function of detecting a decrease in the cooling capacity of the storage battery 1 and issuing information indicating a countermeasure policy. In this manner, the present system 20 has been described as being applied to railway vehicles. However, the application field of the present invention is not limited to this. Other embodiments conceivable within the scope of the technical concept of the present invention are also included within the scope of the present invention. For example, the present system is also suitable for a storage battery system for automobiles whose daily operating patterns are patterned, or for battery-powered forklifts, etc.

[0056] This system 20 makes more efficient use of a battery group (storage battery) 1 having a plurality of battery cells than conventional systems, and has the effect of making it possible to reduce the number of battery cell replacements as much as possible. This system 20 is a computer equipped with a central processing unit (CPU) and a storage device (memory).

[0057] The computer may be a one-chip microcomputer, but it may also be a part of a computer for other purposes, and wireless communication may be performed between the computer of the wayside facility and the moving object. In that case, among the functional configuration blocks shown in Fig. 1, at least the storage battery 1, the cooling mechanism 2, the battery current recorder 4, the battery voltage recorder 5, the battery temperature recorder 6, and the environmental temperature recorder 7 may be arranged on the moving object side as on-board equipment. If the corresponding battery management device 3 is a wayside facility, data may be transferred between them by wireless communication.

[0058] The CPU determines whether or not the battery group 1 needs to be replaced based on the deterioration level of each battery cell calculated based on the detection results of the current sensor and the voltage sensor. When the CPU determines that the battery group 1 needs to be replaced, it identifies the battery group 1 to be replaced based on the deterioration level of the battery group 1. Furthermore, it is preferable that the CPU calculates parameters of a new battery group 1 to be replaced with the battery group 1 to be replaced, or the number of replacements, based on the allowable current value of the new battery group 1.

[0059] The degree of cooling capacity decline may be either quantitative or qualitative. Quantitative means expressing the situation or state of something in numbers. Conversely, qualitative means expressing the change or quality of something in words or letters rather than numbers. In this system 20, if the thresholds and judgment criteria set for quantitative judgment are appropriate, qualitative expressions such as "cooling capacity declined" or "no cooling capacity declined" are also useful.

[0060] This system 20 is capable of quantitatively and / or qualitatively expressing the degree, cause, and near-future prediction of the decline in the cooling capacity of the storage battery 1 or storage battery system 20 under management. In other words, this system 20 is effective by encouraging the operation entity or maintenance workers to take optimally determined measures to eliminate the identified cause in some way.

[0061] This system can be summarized as follows. [1] This system 20 estimates the state of a storage battery 1 equipped with a cooling capacity for a mobile object and supports its maintenance. As shown in FIG. 1, this system 20 includes a battery temperature recording unit 5, an environmental temperature recording unit 7, and a maintenance support information table (11).

[0062] As shown in Fig. 1, the battery temperature recording unit 6 records the daily maximum temperature Tmax detected by a battery sensor attached to the storage battery 1. The environmental temperature recording unit 7 detects and records the maximum value Tamb,max of the environmental temperature Tamb during a period from the start of operation on that day to the time when the maximum temperature Tmax was detected on that day.

[0063] Based on the maximum temperature Tmax detected and recorded according to such a rule and the maximum value Tamb,max of the environmental temperature Tamb, the system 20 judges the degree of cooling capacity degradation. Note that, if the states (degree of deterioration, cooling capacity) of the storage batteries 1 constituting the storage battery system 20 are the same, the maximum temperature Tmax is environment-dependent and is determined by the outside air temperature Tamb.

[0064] In addition, in batteries for mobile applications where the same patterned power load is repeated daily, it is possible to take advantage of the property that the maximum temperature Tmax achieved when the battery system state (degree of deterioration, cooling capacity) is the same is determined by the outside air temperature Tamb.

[0065] In addition, the degree of cooling capacity decline can be determined by where the daily observed value determined by two parameters, the maximum outside temperature Tamb,max and the daily maximum reached temperature Tmax minus the maximum outside temperature Tamb,max dating back from the time the daily maximum reached temperature Tmax was recorded to the start of operation on that day, is plotted. Note that existing sensors for measuring voltage, current, and temperature are sufficient, so there is no need or only a small burden to install additional sensors.

[0066] [2] The present system 20 described in [1] above preferably has a cooling capacity deterioration index calculation unit and a part replacement time prediction unit based on the principles shown in Figs. 2 to 4. These are configured to have the requirements of the functional block diagram of Fig. 1. These do not necessarily have the same names as the names of the functional block diagram described using Fig. 1. As long as the cooling capacity deterioration index calculation unit and the part replacement time prediction unit are functions that are explained at various times, they may be called by any name or in any distributed form. The cooling capacity deterioration index calculation unit calculates a limit cooling capacity deterioration index at which the maximum temperature of the storage battery 1 falls within the upper limit temperature.

[0067] That is, the cooling capacity degradation index calculation unit determines a value obtained by subtracting the daily maximum temperature Tmax from the maximum outside air temperature Tamb,max dating back from the time when the daily maximum temperature Tmax was recorded to the start of operation on that day, and dividing the result by the resistivity SOHR of the storage battery 1 to obtain a cooling capacity degradation index, as defined by the above formulas (2) and (3). As shown in Fig. 2, the system 20 determines whether or not there is a cooling capacity degradation based on where the two parameters, the cooling capacity degradation index and the maximum outside air temperature Tamb,max, are plotted.

[0068] The part replacement timing prediction unit can notify the appropriate time for part replacement based on the current cooling capacity deterioration index and the predicted cooling capacity deterioration amount due to operation. The parts to be replaced are at least either the storage battery 1 itself or the cooling mechanism parts. As to which parts are to be replaced, it is sufficient to follow the countermeasure policy determined in the manner shown in the table in FIG. 4.

[0069] In this way, the system 20 can predict the cause and near-future outcome of a decline in cooling capacity, and can prompt the operation body or maintenance workers to take optimal measures. In this way, the system 20 appropriately issues support information such as battery replacement, cooling (mechanical part) replacement, or control change, as shown in Fig. 4, in order to eliminate the identified cause.

[0070] [3] In the present system 20 described in [2] above, the part replacement timing prediction unit can notify the appropriate time for part replacement as the number of remaining possible runs until part replacement based on the predicted value of the cooling capacity decrease per day of operation. In other words, the present system 20 can clearly notify the limit at which operation can be continued at the current operating frequency for the replacement part identified to eliminate the cause of the cooling capacity decrease, i.e., the deadline for future replacement.

[0071] [4] In the present system 20 described in [3] above, the part replacement time prediction unit preferably calculates a limit cooling capacity deterioration index based on the deterioration rate and operation information of the storage battery 1. This part replacement time prediction unit is configured to have the requirements of the functional block diagram in Fig. 1. The degree of cooling capacity deterioration can be quantitatively determined based on the calculation result of the part replacement time prediction unit.

[0072] [5] In the present system 20 described in [4] above, it is preferable that the part replacement time prediction unit calculates the limit cooling capacity deterioration index using information on weather conditions during the operation period. Here, too, the part replacement time prediction unit is configured to have the requirements of the functional block diagram of Figure 1. The degree of cooling capacity deterioration can be quantitatively determined based on the result of the limit cooling capacity deterioration index calculated by the part replacement time prediction unit.

[0073] The battery storage system 20 that is the subject of management by this method is designed so that its cooling capacity does not exceed the upper limit even on extremely hot days, let alone when the weather conditions are cool. Nevertheless, if the calculation result of the limit cooling capacity decrease index in this system 20 indicates overheating, information on appropriate countermeasures is issued.

[0074] [6] In the system 20 described in [5] above, the part replacement timing prediction unit uses the railway vehicle's regular maintenance plan and operation plan to notify the part replacement timing of the regular maintenance timing just before the predicted value of the cooling capacity degradation index exceeds the limit cooling capacity degradation index.

[0075] This system 20 is suitable for managing a storage battery system 20 for railway applications (including the storage battery 1) as a main management object. In the storage battery system 20 for railway applications, roughly the same pattern of power load characteristics (load pattern) is repeated every day in accordance with the train schedule.

[0076] Therefore, when the frequency of use is constant and continuous, such as in the case of regular service vehicles, not only for railways but also for various other types of transport vehicles, the degree of deterioration of components can be estimated by multiplying the deterioration rate according to the frequency of use by the elapsed time. The regular maintenance plan for railway vehicles referred to here is a time chart that determines the replacement timing for each part with a known usable lifespan.

[0077] Furthermore, the system 20 determines the timing of regular maintenance to be the time immediately before the predicted value of the cooling capacity degradation index exceeds the limit cooling capacity degradation index. The system 20 incorporates the regular maintenance timing into a time chart for each train and uses it for calendar (schedule) management. By performing calendar management, the system 20 notifies maintenance workers and the like of the regular maintenance timing.

[0078] The timing of the regular maintenance notified in this manner is immediately before the predicted value of the cooling capacity degradation index exceeds the limit cooling capacity degradation index. This timing is set based on the technical common sense of quality control, with respect to the specific lifespan known for each managed part, while eliminating waste and leaving a minimum margin. As a result, the present system 20 is effective by urging the operation entity or maintenance worker, etc. to replace parts at an appropriate time, neither too early nor too late, before a breakdown caused by a defective part occurs.

[0079] On the other hand, even for equipment and devices used only in railways, when the frequency of use is sporadic and irregular, the degree of deterioration of components does not necessarily progress at the same rate as deterioration over time. In this case, the system 20 replaces parts at the optimal timing by revising the regular maintenance plan set for each railway car forward or backward based on the index of frequency of use calculated from the train operation plan.

[0080] That is, in this system 20, if train operation plans are infrequent, the maintenance cycle is extended. Conversely, in this system 20, if train operation plans are frequent, the maintenance cycle is shortened. In this way, the system is effective in encouraging the operation body or maintenance workers to replace parts at the appropriate time, not too early and not too late, before a breakdown caused by a defective part occurs. [Explanation of symbols]

[0081] 20... battery system (this system), 1... battery group (storage battery), 2... cooling mechanism, 3... battery management device, 4... battery current recording unit, 5... battery voltage recording unit, 6... battery temperature recording unit, 7... environmental temperature recording unit, 8... resistivity calculation unit, 9... maximum reached temperature extraction unit, 10... factor determination index calculation unit, 11... factor determination unit, SOHR... rate of increase in internal resistance value due to deterioration of battery cell, Tamb... environmental temperature, Tamb,max... maximum reached value of (Tamb environmental temperature), Tmax... maximum reached temperature

Claims

1. A storage battery system capable of estimating a state of a storage battery having a cooling capacity for a mobile body and supporting maintenance, a battery temperature recorder that detects and records a maximum temperature Tmax on a daily basis using a temperature sensor attached to the storage battery; an environmental temperature recording unit that detects and records a maximum reached value Tamb,max of the environmental temperature Tamb in a time period going back from the time when the maximum reached temperature Tmax was detected to the start time of the operation of the day; a maintenance support information table in which countermeasure policies associated with the states of the storage batteries are stored; Equipped with A decrease in cooling capacity is determined based on the maximum reached temperature Tmax and the maximum reached value Tamb,max of the environmental temperature Tamb; estimating a state of the storage battery based on the result of the determination of the cooling capacity decrease; and outputting information selected from the maintenance support information table based on the estimated state of the storage battery. Battery storage system.

2. a cooling capacity degradation index calculation unit that calculates a limit cooling capacity degradation index at which a maximum temperature of the storage battery falls within an upper limit temperature; a part replacement timing prediction unit that notifies the user of an appropriate time for part replacement based on a current cooling capacity deterioration index and a predicted cooling capacity deterioration amount due to operation; Further comprising The battery system according to claim 1 .

3. the part replacement time prediction unit notifies the appropriate time for part replacement as the number of remaining possible operations until part replacement based on a predicted value of a cooling capacity decrease per day of operation; The battery system according to claim 2 .

4. The part replacement time prediction unit calculates a limit cooling capacity deterioration index capable of determining a deterioration in cooling capacity from a deterioration rate of the storage battery and operation information. The battery system according to claim 3 .

5. The part replacement time prediction unit calculates the limit cooling capacity deterioration index using information on weather conditions during an operation period. The battery system according to claim 4.

6. the part replacement timing prediction unit uses a regular maintenance plan and an operation plan for the railway vehicle and notifies, as a part replacement timing, a regular maintenance timing immediately before a predicted value of a cooling capacity deterioration index exceeds the limit cooling capacity deterioration index. The battery system according to claim 5 .

7. A storage battery maintenance support method in which a computer estimates a state of a storage battery having a cooling capacity for a mobile object and supports maintenance, comprising: The computer includes: a step of freely reading out a maintenance support information table in which information on countermeasure policies associated with the state of the storage battery is stored; A step of detecting and recording a maximum temperature Tmax reached by the storage battery on a daily basis using a temperature sensor attached to the storage battery; A step of detecting and recording a maximum reached value Tamb,max of the environmental temperature Tamb in a time period going back from the time when the maximum reached temperature Tmax was detected to the start time of operation of the day; A step of determining a decrease in cooling capacity based on the maximum reached temperature Tmax and a maximum reached value Tamb,max of the environmental temperature Tamb; estimating a state of the storage battery based on a result of the determination of the cooling capacity decrease; outputting information selected from the maintenance support information table based on the estimated state of the storage battery; having Storage battery maintenance support method.

8. A step of calculating a limit cooling capacity deterioration index at which the maximum temperature of the storage battery falls within an upper limit temperature; a part replacement timing prediction step of predicting and notifying an appropriate time for part replacement based on a current cooling capacity deterioration index and a predicted value of a cooling capacity deterioration amount due to operation; Further comprising The battery maintenance support method according to claim 7.

9. The part replacement time prediction step notifies an appropriate time for part replacement as a remaining number of possible operations until part replacement based on a predicted value of a cooling capacity decrease amount per day of operation. The battery maintenance support method according to claim 8.

10. The part replacement time prediction step calculates a limit cooling capacity deterioration index capable of determining a cooling capacity deterioration based on a deterioration rate of the storage battery and operation information. The battery maintenance support method according to claim 9.

11. The part replacement time prediction step calculates the limit cooling capacity deterioration index using information on weather conditions during an operation period. The battery maintenance support method according to claim 10.

12. The part replacement timing prediction step uses a regular maintenance plan and an operation plan of the railway vehicle, and notifies the timing of regular maintenance immediately before the predicted value of the cooling capacity deterioration index exceeds the limit cooling capacity deterioration index as the part replacement timing. The battery maintenance support method according to claim 11.

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