Battery deterioration determination system

Abstract

To provide a battery deterioration determination system that can make a criterion reflecting the influence from a usage state.SOLUTION: A battery deterioration determination system includes, in a storage unit, cumulative data having, for a predetermined period, data measured by an external information measurement unit, and voltage behavior information consisting of at least one of the arrival time from the start of charging of a battery until when a terminal voltage reaches a predetermined voltage set to be less than the maximum voltage, a voltage drop value at the end of the charging of the battery, a voltage drop value at the start of discharging of the battery, the arrival time from the start of the discharging of the battery until when the terminal voltage reaches the predetermined voltage, and a voltage rise value at the end of the discharging of the battery, which are obtained through measurement, can make a determination condition for the battery on the basis of the cumulative data, and can compare the determination condition created on the basis of the cumulative data with newly measured data to determine deterioration of the battery.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a battery deterioration determination system. [Background technology]

[0002] Photovoltaic self-consumption battery systems using batteries that store surplus power from photovoltaic power generation and the like are known, but the batteries that store power deteriorate depending on frequency of use and aging. When a battery deteriorates, the capacity of the battery (current that can be passed per hour, etc.) decreases. For this reason, there is a demand for a technology that estimates the timing of battery replacement and the degree of deterioration. In order to meet such demands, for example, the technology shown in Patent Document 1 records the relationship between the time required for the terminal voltage of a battery to reach constant voltage charging (maximum voltage of the battery) during constant current charging. This is because the deterioration of the battery is diagnosed by utilizing the fact that the time required for the terminal voltage to reach constant voltage charging becomes shorter due to continuous use, etc. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-52033

[0004] However, the time until the battery voltage terminal of the battery reaches a constant voltage charging may be longer or shorter depending on the external environment such as the temperature, humidity, and atmospheric pressure of the battery installation location, and the magnitude of the charging current. On the other hand, the technology disclosed in Patent Document 1 does not take into consideration the installation environment of the battery. In other words, it is not desirable to diagnose the deterioration of the battery by only checking the time until the battery terminal voltage reaches a constant voltage charging. Summary of the Invention [Problem to be solved by the invention]

[0005] The inventors of the present invention have made extensive research into this issue and have attempted to solve it. The problem that the present invention aims to solve is to provide a battery deterioration diagnosis system that can create a judgment criterion that reflects the influence of the usage situation. [Means for solving the problem]

[0006] In order to achieve the above object, a battery charging device includes a terminal voltage detection unit capable of measuring the terminal voltage of a battery, an external information measurement unit capable of measuring one of the pieces of information that affect the behavior of the terminal voltage when the battery is charged or discharged, a storage unit capable of storing data measured by the external information measurement unit, a judgment condition setting unit capable of setting judgment conditions based on information from the storage unit, and a calculation unit capable of performing calculations to make judgments based on the judgment conditions set by the judgment condition setting unit, and the storage unit stores the time from the start of charging until the terminal voltage reaches a predetermined voltage that is set to be less than the maximum voltage, the voltage drop at the end of charging the battery, and other information obtained by the measurement. and data measured by an external information measurement unit, the judgment condition setting unit being capable of creating judgment conditions for the battery based on the accumulated data, and the calculation unit being capable of comparing the judgment conditions created based on the accumulated data with newly measured voltage behavior information and data from the external information measurement unit to determine battery deterioration.

[0007] Moreover, it is preferable that the judgment condition setting unit is configured to be able to set the judgment condition based on the correlation between the voltage behavior information contained in the accumulated data and the multiple types of data measured by the external information measuring unit.

[0008] In addition, the data measured by the external information measurement unit contained in the accumulated data contains information regarding temperature, and the judgment condition setting unit is capable of deriving a calculation formula expressing the correlation between temperature and voltage behavior information based on the accumulated data, setting a degradation diagnosis region in a range where the value is at least a predetermined amount smaller than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula, and setting an abnormality diagnosis region in a range where the value is at least a predetermined amount larger than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula, or setting a degradation diagnosis region in a range where the value is at least a predetermined amount larger than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula, and setting an abnormality diagnosis region in a range where the value is at least a predetermined amount smaller than the calculated voltage behavior value, and it is preferable that the configuration be such that it is possible to determine that the battery has deteriorated using the degradation diagnosis region, and to determine that an abnormality has occurred in the battery using the abnormality diagnosis region.

[0009] In addition, it is preferable to set an accumulated data collection period during which accumulated data is collected, and a judgment period during which battery judgment conditions can be created and judgment can be made based on the accumulated data obtained during the accumulated data collection period, and to configure the device to include an accumulated data collection time judgment means that sets abnormal deterioration judgment conditions used during the accumulated data collection period separately from the judgment conditions used during the judgment period.

[0010] It is also preferable that the configuration include a specific area generation means for setting a specific area having a two-dimensional or three-dimensional extent from accumulated data containing voltage behavior information and data measured by the external information measurement unit for a predetermined period of time.

[0011] It is also preferable to configure the device to include a sudden change determination means that acquires voltage behavior information and data from the external information measurement unit at predetermined intervals, and determines that a problem has occurred when a change in the acquired numerical value, or a change in a predetermined numerical value derived using the acquired numerical value, exceeds a predetermined value.

[0012] It is also preferable that the battery usage conditions be memorizable, and the accumulated data include voltage behavior information and data measured by the external information measurement unit for a predetermined period for each battery usage condition, so that judgments can be made based on judgment conditions that correspond to the battery usage conditions.

[0013] It is also preferable to have an output unit capable of outputting to the outside information that the battery is degraded and information that an abnormality has occurred in the battery, and to have a configuration that can be set so that the number of times that newly measured voltage behavior information and the measurement data of the external information measurement unit need to fall into the abnormality diagnosis region before the output unit outputs to the outside information that an abnormality has occurred in the battery is less than the number of times that newly measured voltage behavior information and the measurement data of the external information measurement unit need to fall into the deterioration diagnosis region before the output unit outputs to the outside information that the battery is degraded.

[0014] It is also preferable that the battery deterioration determination system comprises a terminal voltage detection unit capable of measuring the terminal voltage of the battery, a current measurement unit capable of measuring the charging current or integrated current to the battery, an external information measurement unit capable of measuring one of the pieces of information that affect the behavior of the terminal voltage when the battery is charged or discharged, a memory unit capable of storing data measured by the external information measurement unit, a judgment condition setting unit capable of setting judgment conditions based on the information in the memory unit, and a calculation unit capable of performing calculations to make a judgment based on the judgment conditions set by the judgment condition setting unit, wherein information on at least the terminal voltage, integrated current, and data measured by the external information measurement unit is stored in the memory unit, the judgment condition setting unit is capable of setting the judgment conditions using at least the terminal voltage, integrated current, and data measured by the external information measurement unit stored in the memory unit, and the calculation unit is capable of determining battery deterioration by comparing the judgment conditions created based on the stored data with the newly measured terminal voltage and integrated current and data from the external information measurement unit. Effect of the Invention

[0015] The present invention can provide a battery deterioration diagnosis system capable of creating a judgment criterion that reflects the influence of the usage situation. [Brief description of the drawings]

[0016] [Figure 1] FIG. 13 is a diagram showing an example of charging by constant current constant voltage charging. [Diagram 2] 1A and 1B are diagrams illustrating an example of the behavior of lithium ions during charging and discharging in a lithium ion battery. [Diagram 3] 1 is a diagram showing an example in which a battery deterioration determination system is employed in a configuration in which a battery that is charged using a solar cell is used as a load facility. [Figure 4] This is a graph showing the relationship between charging time and terminal voltage when a substantially empty battery is charged, with the number of times the battery has already been charged being known at the time of measurement. [Diagram 5] This is a diagram showing an example in which a dashed line is added to FIG. 4. However, the dashed line is added at the position of 3.8 V, which is set as the predetermined voltage. [Figure 6] This is a graph showing the relationship between the time required for a battery to reach 3.8V after starting charging a substantially empty battery and the outside air temperature. Note that the number of times the battery has already been charged at the time of measurement is also shown. Also, 3.8V is a set value for the predetermined voltage. [Figure 7] 11 is a diagram showing an example of the relationship between time and terminal voltage when a substantially empty battery is charged and then discharged at a constant current; FIG. [Figure 8] FIG. 13 is a diagram showing an example of data accumulation. [Figure 9] FIG. 13 is a diagram showing an example in which a calculation formula is derived from accumulated data and a determination condition is set. [Figure 10] FIG. 13 is a diagram showing an example of a calculation formula derived by using the current value of the charging current on the horizontal axis and the time it takes for the terminal voltage to reach a predetermined voltage on the vertical axis. [Figure 11] FIG. 13 is a diagram showing an example in which a determination condition is set using the "temperature" of the outside air, the "current value" of the charging current, and the "time required for the terminal voltage to reach a predetermined voltage." [Figure 12]FIG. 13 is a diagram showing an example in which a calculation formula is derived by comparing provisionally input data with accumulated data. [Figure 13] FIG. 13 is a diagram showing an example in which an alarm is issued when measurement data falls within a deterioration determination range multiple times. [Figure 14] FIG. 13 is a diagram showing an example in which a use-prohibited area is set in a part of a deterioration determination area. [Figure 15] FIG. 13 is a diagram showing an example in which a warning is issued when measurement data falls within an abnormality determination region once. [Figure 16] FIG. 13 is a diagram illustrating an example of how to determine a determination method. [Figure 17] FIG. 11 is a diagram illustrating an example of how to determine attributes of measurement data. [Figure 18] This figure shows that the integrated current affects the terminal voltage regardless of the charging time. However, the time it takes for the integrated current to reach 1000 mA is shorter in the example shown in (a) than in the example shown in (b). [Figure 19] FIG. 11 is a diagram illustrating an example of the relationship between an integrated current and a terminal voltage. [Figure 20] FIG. 13 is a diagram showing an example in which a judgment condition is set using the "temperature" of outside air, an integrated current, and a terminal voltage. [Figure 21] This figure shows that the accumulated data collection period and the judgment period are separated, and different judgment conditions are used for each period. [Figure 22] This is an image showing how the entire data obtained during the accumulated data collection period was checked against the criteria. The rectangular framed areas indicate areas that are degraded or abnormal. [Figure 23] This is a diagram showing that the area corresponding to the deterioration or abnormality shown in FIG. 22 is a collection of areas I to IV. [Figure 24] This is a graph showing an example of data collected over the course of about a year, broken down by when learning began. [Diagram 25] FIG. 13 is a diagram showing an example in which a specific area having a two-dimensional extent is set based on accumulated data. [Figure 26]This figure shows how the specific areas created each year are gradually moving. [Figure 27] This is a diagram showing an example in which an abnormality determination region or a deterioration determination region is determined to correspond to a specific region, and in addition to the initial specific region, two examples of specific regions that are shifted from the initial position but are considered to be within the normal range are also shown. [Figure 28] FIG. 13 is a diagram showing distribution of arrival times in each temperature range of stored data. [Figure 29] This is a diagram showing the distribution of arrival times in a certain temperature range shown in Fig. 28. However, this is an example in which data corresponding to the average value ±1 standard deviation is selected. [Diagram 30] 1 is a diagram showing an example of arranging pseudo data so that arrival times are dispersed at a certain temperature, where the range indicated by the dashed line is the dispersion range. [Diagram 31] 1 is a diagram showing an example of arranging a plurality of pseudo data so that the temperature and arrival time are dispersed, where the dispersed range is within the dashed circle. [Diagram 32] FIG. 13 is a diagram showing an example of aging changes in arrival time at a certain temperature. [Diagram 33] FIG. 13 is a diagram showing an example of the change over time of a regression line. [Diagram 34] FIG. 13 is a diagram showing an example of aging of a specific area due to deterioration. [Diagram 35] 1A is a diagram illustrating a method for determining an abnormality due to aging, and FIG. 1B is a diagram illustrating an example of aging of a specific area due to an abnormality, and FIG. 1B is a diagram illustrating a state in which an abnormality determination area changes due to aging. [Diagram 36] This figure shows an example of the degree of change each year, but also shows examples of reference values ​​used to judge deterioration, etc. [Figure 37] FIG. 13 is a diagram showing an example of how to calculate the difference between the maximum value and the minimum value of each specific area. [Figure 38] This figure shows an example of the difference between the maximum and minimum values ​​for a specific area for each year. However, it also shows an example of the reference value used to judge deterioration, etc. [Figure 39]FIG. 13 is a diagram showing an example of accumulated data organized according to usage conditions determined by discharge current and usage time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The following describes an embodiment of the invention. First, a brief description will be given of an example of events that occur when charging a battery 53. When charging begins, the charge level gradually increases. As the charge level increases, the battery terminal voltage also increases and reaches a maximum (e.g., 4.2V). When the terminal voltage reaches its maximum, the amount of current is reduced to prevent the terminal voltage from increasing any further (see FIG. 1).

[0018] By the way, ions and the like move when charging or discharging the battery 53. For example, in the case of a lithium ion battery, lithium ions move (see FIG. 2).

[0019] When battery 53 is used in a place with high temperatures, the battery temperature also rises. As the battery temperature rises, the internal resistance of the battery decreases, the internal chemical reactions become more active, and the battery becomes easier to charge (the movement of ions). In addition, because the voltage required for charging decreases due to the decrease in internal resistance (V=IR), the time it takes for the terminal voltage to reach its maximum becomes longer.

[0020] On the other hand, when the battery 53 is used in a place with a low temperature, the battery temperature drops and the internal resistance increases. When the internal resistance increases, chemical reactions are less likely to occur and the voltage required for charging increases. This shortens the time it takes for the terminal voltage to reach its maximum. In other words, even for the same battery 53, the time it takes for the terminal voltage to reach its maximum varies depending on the region and season in which it is used.

[0021] Here, the photovoltaic self-consumption battery system 5 will be taken as an example for explanation. The photovoltaic self-consumption battery system 5 shown in FIG. 3 includes a high-voltage power receiving facility 52 equipped with a conversion device that converts electricity supplied from a power company into a voltage and frequency that match the specifications of a consumer's load facility 51. The system also includes a battery 53 capable of storing electricity generated by a photovoltaic cell 54. The electricity stored in the battery 53 can be supplied to the load facility 51 via the conversion device of the high-voltage power receiving facility 52. ​​Therefore, it is possible to store surplus electricity generated by the photovoltaic cell 54 in the battery 53 and supply it to the load facility 51 from the battery 53 at night or the like. The battery 53 shown in FIG. 3 is connected to a management device 55 that can store the results of measuring the current, terminal voltage, and outside air temperature (battery temperature) during charging and discharging.

[0022] 3 includes a memory unit 551 capable of storing data of the measuring device so as to be collected, a judgment condition setting unit 552 capable of setting judgment conditions based on information from the memory unit 551, a calculation unit 553 such as a processor that can be used when making judgments about abnormalities and the like based on information from the judgment condition setting unit 552, and an output unit 554 capable of outputting to the outside based on the calculation results in the calculation unit 553. The output unit 554 shown in FIG. 3 can output a signal used to stop charging and discharging the battery 53.

[0023] 3, a terminal voltage detection unit capable of measuring the terminal voltage of battery 53 and a temperature detection unit capable of detecting the temperature of battery 53 are provided. Note that other measuring devices capable of detecting the state of battery 53 may also be provided.

[0024] 3 stores external environment information such as outside air temperature, humidity, atmospheric pressure, solar radiation, weather, and anemometer, which is information outside the battery 53. The storage unit 551 also stores external electrical information related to electricity flowing outside the battery 53, such as a charging current and an integrated current to the battery 53. The external environment information and external electrical information are information detected by an external information measurement unit, and at least a part of the information detected by the external information measurement unit is stored in the storage unit 551.

[0025] 3 is a lithium ion battery, but the battery 53 may be other types of batteries, such as a lead battery or a nickel-metal hydride battery. Here, the relationship between the charging time and the terminal voltage in constant current / constant voltage charging (CCCV charging) and the relationship between the number of times the battery 53 has been charged will be explained. However, the following explanation will be given using a lithium ion battery as an example.

[0026] As a method of charging the battery, CCCV charging (CCCV: Constant Current, Constant Voltage) as shown in the schematic diagram in Fig. 1 is performed. When CCCV charging is performed, when charging of battery 53 is started from a fully discharged state, the terminal voltage is low at the beginning of charging, so constant current charging is performed. As the charge amount increases with charging, the terminal voltage also increases. For example, when the terminal voltage reaches 4.1V to 4.2V, constant voltage charging is performed. Furthermore, by performing constant voltage charging so that the terminal voltage does not exceed 4.2V, the amount of current supplied to battery 53 is reduced.

[0027] An example of the test results when such charging is performed is shown in Figure 4. Figure 4 shows the results of measuring the time it takes to reach the maximum voltage when charging from a substantially empty state, each time a specific number of charges are performed under the same temperature conditions. Comparing 1600 cycles and 3200 cycles, it can be seen that the time it takes to reach the maximum terminal voltage of the battery does not increase with the number of cycles.

[0028] The reason for this is thought to be that as the voltage increases, not only lithium ions but also "other substances produced from the electrodes" or "ions that have chemically reacted with the electrodes" move within the electrolyte. In other words, reactions that occur when the battery is charged or discharged affect the internal resistance, so even if the battery is being charged during CC charging (constant current charging), it may take longer to reach the maximum voltage when the battery is charged, even if the number of cycles increases.

[0029] For this reason, it is not preferable to judge the degree of deterioration of the battery 53 based on the time until the terminal voltage of the battery 53 reaches its maximum. It is preferable to use the time until a predetermined voltage set to be less than the maximum voltage for the judgment. This predetermined voltage is preferably set to the terminal voltage value before the stage at which an unintended chemical reaction occurs in the electrolyte, but it is difficult to determine in advance what value or lower corresponds to such a state. For this reason, it is preferable to set it based on experience.

[0030] In the example shown in Fig. 5, the predetermined voltage is set to 3.8 V, but it does not have to be this value. However, at the start of charging, the main reaction is the forward reaction of only the movement of lithium ions, and as the terminal voltage approaches its maximum, side reactions become dominant, so it is better not to set the value close to the maximum terminal voltage.

[0031] For example, it is preferable to set the predetermined voltage to 60% or less of the terminal voltage increase from the start of charging to full charge, relative to the terminal voltage at the start of charging when the forward reaction of lithium ion movement is the main reaction. For example, if the terminal voltage in an empty state is 3.6V and the terminal voltage in a fully charged state is 4.1V, the terminal voltage will increase by 0.5V from the start of charging to full charge. In this case, 3.6V + 0.5V x 0.6 = 3.9V, so it is preferable to set the predetermined voltage to 3.9V or less.

[0032] Also, if the predetermined voltage is not much different from the terminal voltage at the start of charging, the time to reach the predetermined voltage may be too short. For this reason, it is preferable to set the predetermined voltage to a voltage that takes about 10 minutes or more to reach at 0 cycles. In the example shown in Figure 4, the predetermined voltage is set to 3.7V or more.

[0033] Considering these, the predetermined voltage is set in the range of 3.7 to 3.9V, for example. In order to ensure the arrival time, it is more preferable to set the "predetermined voltage" in the range of 3.8 to 3.9V. In the example shown in FIG. 4, if the predetermined voltage is adopted in such a range, it is understood that the relationship that the time to reach the predetermined voltage becomes shorter as the number of cycles increases is maintained. Note that this value is shown as an example, and varies depending on the type and size of the battery 53. In the case of the battery 53, when the predetermined voltage is set to 40% or less of the increase in the terminal voltage, it is of course possible to set the predetermined voltage to 3.8V, or to set the time required to reach the predetermined voltage to about 10 minutes as about 7 minutes. It is preferable that the predetermined voltage is a terminal voltage where the only reaction in which ions move is a forward reaction is the main reaction, and that the time until the battery 53 reaches the predetermined voltage is a positive relationship.

[0034] Incidentally, the time it takes to reach a given voltage also increases or decreases depending on the battery temperature. For example, when the given voltage is set to 3.8V, the relationship between the time required to reach the given voltage from the start of charging and the outside air temperature is as shown in Figure 6. As can be seen from Figure 6, the outside air temperature has an effect on the time required to reach the given voltage from the start of charging. It can also be seen that the effect of the outside air temperature exists regardless of the number of cycles.

[0035] From the data shown in FIG. 6, it can be said that "the time required to reach a specified voltage decreases as the outside air temperature decreases" and "the time required to reach a specified voltage decreases as the number of cycles increases."

[0036] Other than the outside temperature, there are other factors that can affect the behavior of the terminal voltage. For example, these are weather, solar radiation, humidity, and air pressure. Other than the external environmental information such as the outside temperature, weather, solar radiation, humidity, and air pressure, there are other factors that can affect the behavior of the terminal voltage. For example, there is external electrical information such as the charging current to the battery 53 and its integrated current.

[0037] However, it is not only the "time to reach a certain voltage" that changes depending on the usage cycle of the battery 53. Looking at Fig. 4, it can be seen that the amount of voltage drop immediately after the end of charging also changes depending on the usage cycle of the battery 53. It is also known that the amount of voltage drop immediately after the end of charging changes depending on the temperature of the external environment.

[0038] Also, when discharging, there are phenomena that change depending on the usage cycle of battery 53. It is known that the "amount of voltage drop immediately after starting discharging to a load", "amount of voltage rise after completing discharging to a load", and "time required to reach a predetermined voltage during discharging" (see FIG. 7) also change depending on the usage cycle of battery 53. It is also known that these also change depending on the temperature of the external environment, etc.

[0039] As can be understood from these descriptions, the battery deterioration determination system of the embodiment comprises a "terminal voltage detection unit capable of measuring the terminal voltage of battery 53", an "external information measurement unit capable of measuring one of the pieces of information that affect the behavior of the terminal voltage when battery 53 is charged or discharged", a "memory unit 551 capable of storing data measured by the external information measurement unit", a "determination condition setting unit 552 capable of setting determination conditions based on the information from memory unit 551", and a "calculation unit 553 capable of performing calculations to make a determination based on the determination conditions set by determination condition setting unit 552".

[0040] In addition, the battery deterioration determination system of the embodiment has stored data in the memory unit 551 that includes ``voltage behavior information obtained by measurement, which is composed of at least one of ``the time from the start of charging until the terminal voltage reaches a predetermined voltage set less than the maximum voltage,'' ``the voltage drop value at the end of charging of battery 53,'' ``the voltage drop value at the start of discharging of battery 53,'' ``the time from the start of discharging of battery 53 until the terminal voltage reaches a predetermined voltage,'' and ``the voltage rise value at the end of discharging of battery 53'''' and ``data measured by the external information measurement unit'' for a predetermined period of time.

[0041] Furthermore, the judgment condition setting unit 552 of the battery deterioration judgment system of the embodiment can create judgment conditions for the battery 53 based on the accumulated data. Furthermore, the calculation unit 553 of the battery deterioration judgment system of the embodiment can compare the judgment conditions created based on the accumulated data with newly measured voltage behavior information and data from the external information measurement unit to judge the deterioration of the battery 53. Therefore, it is possible to provide a deterioration diagnosis system for the battery 53 that can create judgment criteria that reflect the influence of the usage situation.

[0042] Here, an example of collection of various data will be described. For example, as shown in FIG. 8, data of the external information measurement unit, the terminal voltage of the battery 53 itself, the amount of voltage drop, the amount of voltage rise, the time it takes for the battery 53 to reach a predetermined voltage, and other data are collected and stored in the storage unit 551. The measurement may be performed continuously throughout the day, or may be performed intermittently. When the measurement is performed intermittently, it is preferable to perform the measurement with, for example, the start of charging the battery 53 as a trigger. Note that data measured by the Japan Meteorological Agency may be used as part of the data of the external information measurement unit.

[0043] The data of the external information measurement unit may be recorded as representative values ​​such as average, median, maximum, and minimum values. Also, all data may be stored instead of storing only information representative of a day. The latter example is preferably applied when the measurement frequency is low, but even if the measurement frequency is high, all data may be stored for a certain period of time and some or all of it may be deleted when the time comes.

[0044] Of the voltage behavior information and data from the external information measurement unit, those handled as being continuously collected in the storage unit 551 are preferably used for comparison with recently measured data. The collection period is preferably, for example, several years or more. In this way, data can be compared, for example, two or three years later.

[0045] Next, an example of creating a judgment condition using the judgment condition setting unit 552 will be described. The judgment condition setting unit 552 creates a judgment condition based on the contents of the storage unit 551. For example, a calculation formula such as a regression line is calculated from data on the time it takes to reach a predetermined voltage in a certain period and data on external information (such as temperature) (see FIG. 9). For example, when the battery 53 deteriorates, changes such as an increase in the slope of the regression line and a change in the intercept may occur. Note that data for finding the calculation formula is preferably collected for several months or more, and more preferably for one year or more. If it is collected for one year or more, data corresponding to seasonal changes and changes due to external information can be known.

[0046] It is preferable to specify a formula such as a regression line from data on the time taken to reach a predetermined voltage in a certain period and external information (such as temperature) to make a "deterioration judgment" or "abnormality judgment" based on the relationship with this formula. For example, in the example shown in FIG. 9, a portion that is a certain distance below the regression line is set as a "deterioration judgment region". This "deterioration judgment region" is set for use in judging the deterioration of the battery 53. For example, the deterioration of the battery 53 is judged based on the judgment result of whether the voltage behavior information and the result of the external information measurement unit belong to this "deterioration judgment region". The deterioration judgment region is provided below the regression line because, when deterioration occurs due to use, the time it takes for the terminal voltage to reach its maximum value becomes shorter, and the measurement data is located below the regression line.

[0047] 9, a portion above the regression line by a predetermined distance is set as an "abnormality determination region." This "abnormality determination region" is set for use in determining whether or not there is an abnormality in the battery 53. For example, based on the determination result of whether or not the voltage behavior information and the result of the external information measurement unit belong to this "abnormality determination region," the abnormality determination of the battery 53 is performed. Note that, since it is not normal for the time it takes for the terminal voltage to reach its maximum to become longer due to degradation, the abnormality determination region is set above the regression line.

[0048] In this example, the horizontal axis is set to temperature and the vertical axis is set to arrival time, so the ups and downs of the relationship with the regression line are determined as described above, but if the horizontal axis is set to arrival time and the vertical axis is set to temperature, the ups and downs of the relationship with the regression line will be reversed. In addition, the deterioration judgment region and abnormality judgment region change depending on the settings of the vertical and horizontal axes.

[0049] As can be understood from these descriptions, it is preferable that the deterioration determination system for battery 53 includes information on temperature in the data measured by the external information measurement unit contained in the accumulated data.

[0050] In addition, the judgment condition setting unit 552 derives a calculation formula expressing the correlation between temperature and voltage behavior information based on the accumulated data, and is preferably capable of "setting a degradation diagnosis region in a range where the value is more than a predetermined amount smaller than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula, and setting an abnormality diagnosis region in a range where the value is more than a predetermined amount larger than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula," or "setting a degradation diagnosis region in a range where the value is more than a predetermined amount larger than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula, and setting an abnormality diagnosis region in a range where the value is more than a predetermined amount smaller than the calculated voltage behavior value."

[0051] It is also preferable that the deterioration determination system for the battery 53 is capable of determining that the battery 53 has deteriorated using the deterioration diagnosis region, and that the battery 53 has an abnormality using the abnormality diagnosis region.

[0052] The settings for the deterioration judgment region and the abnormality judgment region may be incorporated in the judgment condition setting unit 552 in advance, or may be configured so that the user can set them at the desired timing, such as after on-site installation.

[0053] In the above example, the judgment conditions are set using the external information "temperature" and "time required for the terminal voltage to reach the specified voltage", but the external information may be something other than temperature. For example, the judgment conditions may be set using the "current value" of the charging current and the "time required for the terminal voltage to reach the specified voltage" (see FIG. 10).

[0054] Moreover, the judgment conditions may be set using multiple types of external information. For example, the judgment conditions may be set using the "temperature" of the outside air, the "current value" of the charging current, and the "time it takes for the terminal voltage to reach the specified voltage" (see FIG. 11). In the example shown in FIG. 11, the "temperature," the "current value," and the "time it takes for the terminal voltage to reach the specified voltage" correspond one-to-one to the X-axis, Y-axis, and Z-axis, which are orthogonal to each other. By making a judgment using multiple types of external information, it becomes possible to more accurately judge the deterioration state.

[0055] As can be seen from this example, it is preferable that the judgment condition setting unit 552 is configured to be able to set judgment conditions based on the correlation between the voltage behavior information contained in the accumulated data and multiple types of data measured by the external information measurement unit.

[0056] It is not necessary to use only one type of voltage behavior information for the determination. For example, two or more of the following may be used in combination: "time from the start of charging until the terminal voltage reaches a predetermined voltage set to be less than the maximum voltage", "voltage drop value at the end of charging the battery 53", "voltage drop value at the start of discharging the battery 53", "time from the start of discharging the battery 53 until the terminal voltage reaches a predetermined voltage", and "voltage rise value at the end of discharging the battery 53". Of course, all of the above examples may be used in combination. For example, all of the above examples may be compared with values ​​obtained by a new measurement, and if it is determined that there is a problem with any one of them, it may be determined that there is a problem with the battery 53, or it may be determined that there is a problem with the battery 53 only if it is determined that there is a problem with two or more predetermined types or all of them.

[0057] Incidentally, in order to create judgment conditions using data obtained by measurement, it is necessary to collect data for a long period of time (for example, one year). There may be cases where deterioration judgment is required before sufficient data is accumulated. In this way, when it is not appropriate to create judgment conditions using only accumulated data, judgment conditions may be created using both provisionally input data and accumulated data.

[0058] For example, basic data is provisionally input as background data. This background data does not have to be related to the battery 53 to be judged or related to the environment in which the battery 53 is to be used, but if data exists for the same type of battery 53 used in the environment to be judged or a similar environment, it is preferable to use that data.

[0059] Also, data for a short period (for example, one to three months) is accumulated for the battery 53 to be judged. The provisionally input data is compared with the data measured for the battery 53 to be judged, and the deviation is confirmed. For example, a regression line derived from the provisionally input data is compared with a regression line derived from the data measured for the battery 53 to be judged.

[0060] In the example shown in Fig. 12, the slope of the regression line derived from the provisionally input data and the slope of the regression line derived from the data measured on the battery 53 to be judged are similar, but the positions are different. In other words, if expressed as a linear function, the slopes are similar but the intercepts are different. When such a result is obtained, for example, a calculation formula is used as the judgment condition, in which the slope of the regression line derived from the provisionally input data is maintained but the position is shifted.

[0061] In any case, the regression line derived from provisionally input data is compared with the regression line derived from data measured on the battery 53 to be judged, and the judgment conditions are set based on the comparison. For example, when the amount of data obtained in a short period of time is small or there is no data at all, making it impossible to derive a trend, the regression line derived from provisionally input data may be set as the judgment conditions.

[0062] Incidentally, initially, the provisionally input data is controlled to be compared with data measured regarding the battery 53 to be judged, but once sufficient measurement data has been accumulated, the provisionally input data may be controlled not to be used. In this case, the switching may be performed automatically, or a message asking whether or not to switch may be displayed to prompt the user to input a decision. In this case, if the user inputs that the switching should not be performed, the provisionally input data may also be used to create the judgment conditions. Also, if the user inputs that the switching should be performed, the judgment conditions may be created without using the provisionally input data.

[0063] As can be seen from these descriptions, it is preferable to configure the device so that deterioration can be judged even if a sufficient amount of measurement data is not accumulated.

[0064] Incidentally, the calculation unit 553 of the embodiment applies the newly measured voltage behavior information and the data of the external information measurement unit to the judgment condition set by the judgment condition setting unit 552, and judges the state of the battery 53. More specifically, it is possible to judge whether the battery 53 has deteriorated or whether an abnormality has occurred in the battery 53. To make this judgment, it is confirmed whether the newly measured voltage behavior information and the data of the external information measurement unit are in a deterioration judgment region or an abnormality judgment region or not (see FIG. 13).

[0065] Incidentally, in the case of deterioration judgment, if the measurement data falls into the deterioration judgment area only once, it may not be regarded as deterioration judgment. This is because it is possible that the measurement data accidentally falls into the deterioration judgment area only once, and if it is deterioration, there is a low possibility that a problem will occur during use, so there is little need to immediately judge it as deterioration. In this case, it may be judged as deterioration when the data measured during a predetermined period belongs to the deterioration judgment area multiple times (e.g., when it falls into the deterioration judgment area eight times in 10 days) (see FIG. 13). Note that it is preferable to configure so that when a deterioration judgment is made, the output unit 554 can notify an external PC or smartphone.

[0066] It is also possible to determine that the measurement data has deteriorated even if it has entered the deterioration judgment area only once.Also, a "prohibited use area" may be set within the deterioration judgment area, and the measurement data may be determined to have deteriorated even if it has entered the deterioration judgment area only once if it belongs to this "prohibited use area" (see FIG. 14).

[0067] It is preferable to set the "prohibited use area" to correspond to a situation where it is expected that the power supply will be stopped in a short time even if it is used, even within the deterioration judgment area. In this case, since it is an unusable state, it is preferable to notify the outside even if the measurement data enters the "prohibited use area" only once.

[0068] On the other hand, if the measurement data falls within the abnormality determination region, there is a risk of fire due to an abnormality in the battery 53. For this reason, the importance of notification is higher than that of deterioration determination. For this reason, if the measurement data falls within the abnormality determination region even once, it is possible to issue an alarm notification from the output unit 554 or to stop the operation of the battery 53 (see FIG. 15).

[0069] However, since it is possible that measurement data may accidentally fall into the abnormality determination region only once, it is conceivable that when measurement data falls into the abnormality determination region multiple times, an alarm may be issued or operation of battery 53 may be stopped. Also, different control may be implemented in stages depending on the number of times it is confirmed, such as issuing an alarm after one confirmation and stopping operation of battery 53 after multiple confirmations.

[0070] In any case, it is preferable to have an output unit 554 capable of outputting to the outside information that battery 53 is degraded and information that an abnormality has occurred in battery 53, and to have a configuration that can be set so that the number of times that newly measured measurement data is required to fall into the abnormality diagnosis region before output unit 554 outputs to the outside information that battery 53 is degraded is less than the number of times that newly measured measurement data is required to fall into the deterioration diagnosis region before output unit 554 outputs to the outside information that battery 53 is degraded.

[0071] Incidentally, charging is not necessarily performed with a constant current. When charging the battery 53 using a commercial power source, constant current charging is possible, but when charging using solar power generation, the current capacity (accumulated current amount) per unit time is unlikely to be constant, unlike charging using a commercial power source.

[0072] In other words, there are constant current charging and non-constant current charging, but since non-constant current charging must take into account the influence of external environments such as temperature until the terminal voltage reaches a certain voltage, as well as the variation in current capacity per unit time (accumulated current amount), it is preferable to make a judgment different from that for constant current charging. However, if the amount of actual current change is small, even with non-constant current charging, a judgment process similar to that for constant current charging can be adopted (see Figure 16).

[0073] Therefore, it is preferable to determine whether the battery 53 has been charged by constant current charging or non-constant current charging. Whether the charging has been performed by constant current charging or non-constant current charging can be determined based on the amount of change in the integrated current or the charging current charged to the battery 53.

[0074] It is preferable that the collected measurement data is stored separately so that data obtained during constant current charging and data obtained during non-constant current charging can be distinguished. It is also preferable that the stored data can be used to create a judgment condition that matches each condition. When non-constant current charging is performed and the amount of change in current is large, it is preferable that the data obtained at that time is acquired so that it can be distinguished from the data obtained during constant current charging. However, even if the current flows during non-constant current charging, if the amount of change in current per hour or the amount of change in charging current is small, it is not necessary to acquire the data so that it can be distinguished from the data obtained during constant current charging. It is also possible that the data is acquired so that it can be distinguished, but it can be treated in the same way as the data obtained during constant current charging.

[0075] In the case of non-constant current charging, the terminal voltage when the integrated current value reaches a certain current may be used for judgment. The reason for using the integrated current for judgment in the case of non-constant current charging is that when current is supplied from an empty state to a plurality of similarly deteriorated batteries 53 until the integrated value reaches a specific value, each battery 53 shows the same terminal voltage (see FIG. 18).

[0076] In other words, the integrated current and terminal voltage have a specific relationship, but the relationship changes depending on the degree of deterioration, so the degree of deterioration can be verified by examining the integrated current and terminal voltage. This relationship is also true in the case of constant current charging, but with a constant current, the charging time and the integrated current are roughly proportional, so calculations can be made without the concept of integrated current.

[0077] In addition, a judgment is also made in the case of non-constant current charging, but the measurement data for this purpose can be accumulated and a calculation formula can be derived in the same manner as in the case of constant current charging. In the example shown in FIG. 19, measurement data of terminal voltage and integrated current are accumulated, and a calculation formula is derived based on the accumulated data. In the example shown in FIG. 19, the calculation formula is a regression line, and a deterioration judgment region and an abnormality judgment region are set as in the example shown in FIG. 13. However, in the example shown in FIG. 19, the accumulated data is integrated current and terminal voltage, and if the terminal voltage value is large even with the same integrated current, a "deterioration judgment" is made, and if the terminal voltage value is small even with the same integrated current, an "abnormality judgment" is made.

[0078] In non-constant current charging, as in constant current charging, the internal resistance changes depending on the external temperature, so it is preferable to store data taking into consideration the mutual relationships between the external temperature, terminal voltage, and integrated current. It is also preferable to be able to determine deterioration or abnormality from these relationships (see FIG. 20). For example, it is preferable to set a determination condition using a three-dimensional regression surface expressed by a formula, and control the determination of deterioration or abnormality based on the relationship with the formula.

[0079] As can be understood from these descriptions, the present invention includes a terminal voltage detection unit capable of measuring the terminal voltage of battery 53, a current measurement unit 61 capable of measuring the charging current or the integrated current to battery 53, an external information measurement unit capable of measuring one of the pieces of information that affect the behavior of the terminal voltage when battery 53 is being charged or discharged, a storage unit 551 capable of storing data measured by the external information measurement unit, a judgment condition setting unit 552 capable of setting judgment conditions based on the information in storage unit 551, and a calculation unit 553 capable of performing calculations to make judgments based on the judgment conditions set by judgment condition setting unit 552. and 53, in which at least information on the terminal voltage, the integrated current, and the data measured by the external information measurement unit is stored in a memory unit 551, a judgment condition setting unit 552 is capable of setting judgment conditions using at least the information on the terminal voltage, the integrated current, and the data measured by the external information measurement unit stored in the memory unit 551, and a calculation unit 553 is capable of comparing a judgment condition created based on the stored data with a newly measured terminal voltage, an integrated current, and data from the external information measurement unit to judge deterioration of the battery 53.

[0080] Here, consider a case where the accumulated data collection period, which is a period for collecting comparison data for judging deterioration and the like, is set separately from the judgment period for judging the battery 53 (see FIG. 21). The data collected during the accumulated data collection period is data necessary for judging changes in the battery 53, but even the data collected during the accumulated data collection period may contain some abnormal values. However, in consideration of the effect on judgment during the judgment period, it is preferable not to store abnormal values. Also, in some cases, it may not be preferable to continue using the battery in a state where such data is generated.

[0081] For this reason, it is preferable to be able to determine whether the data obtained during the accumulated data collection period indicates an abnormal value. Also, it is preferable that the judgment regarding the data collected during the accumulated data collection period be made using judgment conditions that are set separately from the judgment conditions used during the judgment period. This is because it is preferable to be able to make judgments from a different perspective than the judgments made during the judgment period.

[0082] The example shown in Fig. 22 indicates that there were abnormal values ​​among the multiple collected data. Specifically, the range determined to be an abnormal value is shown as a thick band, and it can be seen that data located within this range indicates an abnormal value. In this case, multiple data are collected and then it is determined whether or not there is data indicating an abnormal value among them, but it is also possible to make the determination each time data is collected.

[0083] In this example, the battery deterioration determination system is set with an accumulated data collection period during which accumulated data having a predetermined period of voltage behavior information and data measured by an external information measurement unit is collected. In addition, a determination period (e.g., one year later) during which a determination condition for the battery 53 is created based on the accumulated data and a determination is made on newly measured measurement data is also set. Furthermore, the accumulated data collection time determination means is set with abnormal deterioration determination conditions to be used only during this accumulated data collection period.

[0084] In the embodiment, the abnormal deterioration judgment conditions used during the accumulated data collection period are set so that if one piece of accumulated data is significantly different from the other data and meets the abnormal deterioration judgment condition only once, it is not stored as accumulated data. Also, if the abnormal deterioration judgment condition is met many times over a continuous period of time, it is judged to be abnormal or deteriorated. In this way, it is possible to improve the accuracy of the abnormality or deterioration judgment.

[0085] Incidentally, it is preferable to provide a plurality of types of abnormal deterioration determination conditions for use during the accumulated data collection period so that it can be determined that a particular situation has been reached. By providing a plurality of types of abnormal deterioration determination conditions, it is possible to divide the range that corresponds to the abnormal deterioration determination conditions into a plurality of ranges (see FIG. 23). In this way, it becomes possible to determine the cause of the problem.

[0086] 23, the region corresponding to the abnormal deterioration determination condition is divided into four regions. Region I indicates a state in which the temperature of battery 53 is low, region II indicates a state in which the temperature of battery 53 is high, region III indicates a state in which the time required for battery 53 to reach a predetermined voltage is longer than usual, and region IV indicates a state in which the time required for battery 53 to reach a predetermined voltage is shorter than usual.

[0087] If the battery falls within the III or IV region, it can be determined that the battery is rapidly deteriorating or is in an abnormal state. This is the same as the determination in normal times. If the battery falls within the I or II region, the temperature of the battery 53 is too low or too high. In that case, it can be inferred that the battery 53 is being used outside the temperature range suitable for its usage environment, or that there is an abnormality on the sensor side. In other words, if the battery falls within the I or II region, unlike the III or IV region, it can be determined that there may be a problem other than with the battery 53.

[0088] If it falls into area I or area II, it is preferable to notify, for example, that there is a possibility that battery 53 is not being used in an environment in which it should be used, or that there is a possibility that an abnormality has occurred in a sensor that measures the temperature of battery 53.

[0089] As can be understood from these descriptions, it is preferable to set an accumulated data collection period, which is a collection period of accumulated data having voltage behavior information for a predetermined period and data for a predetermined period measured by an external information measurement unit, and a judgment period during which judgment conditions for the battery 53 can be created and judgment can be made based on the accumulated data obtained during the accumulated data collection period, and to include an accumulated data collection time judgment means that sets abnormality / deterioration judgment conditions used during the accumulated data collection period separately from judgment conditions used during the judgment period. This is because, by making judgments regarding data collected during the accumulated data collection period using judgment conditions set separately from judgment conditions used during the judgment period, it becomes possible not only to judge abnormality or deterioration of the battery 53 at the time of collecting the accumulated data, but also to judge the system itself, such as judging the appropriateness of the usage environment of the battery 53.

[0090] Incidentally, it is known that the battery 53 deteriorates even during the accumulated data collection period due to continuous data collection, and that differences in the data obtained may occur depending on when the battery 53 is first used (whether it is started in the hot season or the cold season, etc.) (see FIG. 24). In the example shown in FIG. 24, if learning is started in spring or autumn, the variation in the data in the mid-temperature range is large and the variation in the data in the high and low temperature ranges is small. Also, if learning is started in summer or winter, the variation in the data in the temperature range of the season in which learning is started is large, and the variation in the data becomes smaller as the temperature moves away from that range.

[0091] While considering how to handle this kind of data, we came up with the idea of ​​using a method to find specific areas with a two-dimensional spread from the accumulated data, rather than a method to find an approximate straight line from the accumulated data (see Figure 25).

[0092] As already described, the time required to reach a predetermined voltage decreases due to aging. For this reason, in the method of calculating an approximation line, the intercept of the approximation line becomes smaller every year, for example. Even when calculating a specific area from accumulated data, a shift occurs in the position of the specific area for the same reason (see FIG. 26).

[0093] In the example shown in Figure 26, the specific area moves downward due to aging. The degree of movement of the specific area can be used as a criterion for determining deterioration, etc. If the specific area is found from the accumulated data and the degree of movement is used for the determination, it is possible to expect results with the same or higher accuracy as when a regression line is found. Note that the specific area can be found, for example, by performing a calculation to derive a shape that includes all or a major part of the accumulated data within the specific area while reducing its area.

[0094] As can be understood from these descriptions, it is preferable to configure the specific area generating means to set a specific area having a two-dimensional spread from accumulated data having voltage behavior information and data measured by the external information measuring unit for a predetermined period of time. Note that, in this embodiment, a specific area having a two-dimensional spread is set based on the relationship between the arrival time and the temperature, but multiple values ​​such as integrated current-arrival time may be used, or a specific area having a three-dimensional spread may be set based on the relationship between the arrival time, temperature, and integrated current.

[0095] However, even when a specific area having a two-dimensional extent is set using a specific area generating means, the specific area may move due to deterioration over time, as described above, so it is preferable to set an abnormality judgment area and a deterioration judgment area so that signs of abnormality and deterioration can be detected. In this case, it is preferable to set the abnormality judgment area and the deterioration judgment area so that they correspond to the specific area set using the specific area generating means (see FIG. 27).

[0096] Here, an example of how to derive the regression line and the specific area will be described. As usual, the regression line can be derived by using the least squares method to derive a linear equation so that the distance between all data and the line is short. However, it is also possible to grasp the distribution of arrival times in each temperature zone and use the results to derive the regression line. For example, data that corresponds to the average value of each temperature zone ± n standard deviations (n ​​is a natural number) is selected, and the regression line is derived by using the least squares method for that data (see Figures 28 and 29).

[0097] Also, when a specific zone is set using a specific zone generating means, the distribution of arrival times in each temperature zone may be grasped and the result may be used to set the specific zone. For example, as shown in FIG. 28, the distribution of arrival times in each temperature zone may be grasped and the result may be used to set the specific zone. For example, the average value of each temperature zone ± n standard deviations (n ​​is a natural number) may be set as the zone portion of that temperature zone (see FIG. 29), and the zone portions of each temperature zone may be integrated to derive the entire specific zone. The specific zone may also be derived using an approximation curve.

[0098] Incidentally, even during the accumulated data collection period, there may be cases where it is desired to make a judgment about the battery 53 using the collected data. However, such a request may arise when there is only a small amount of collected data. Therefore, pseudo data may be created based on the collected data, and may also be used for the judgment.

[0099] For example, pseudo data is created for some of the obtained data such that the arrival times at the temperatures to which the data belongs are distributed (see FIG. 30). Of course, pseudo data may also be created such that the temperatures at the arrival times to which the data belongs are distributed. Furthermore, pseudo data may be arranged so that the arrival times and temperatures are distributed from the data (see FIG. 31). Note that, when a predetermined number of pieces of data have actually been accumulated, it is preferable to control the system so that the judgment conditions are automatically set using only the actually measured data, for example by deleting the pseudo data.

[0100] However, the battery 53 may deteriorate gradually and its capacity may decrease depending on the number of times it is used or the number of years it is used, but the deterioration of the battery 53 may progress rapidly. In such a case, there may be a large difference between the timing at which the result that the battery is in the deterioration judgment range is obtained and the timing at which the deterioration symptoms occur. For this reason, it is preferable to be able to grasp the rapid progression of deterioration.

[0101] Therefore, it is preferable to acquire voltage behavior information and data from the external information measurement unit at predetermined intervals, and determine that a problem has occurred when the acceleration of change in a predetermined numerical value becomes greater than or equal to a predetermined value.

[0102] For example, the change in a certain value at a predetermined temperature is focused on, and the acceleration of the change is confirmed. In the example shown in FIG. 32, the change in the arrival time at a predetermined temperature is focused on. Data is confirmed every year from a certain point until four years have passed, and the arrival time shortens at approximately the same pace from the first to the fourth year, but the change in the arrival time from the fourth to the fifth year is much larger than before. In other words, the rate of change in the yearly unit is significantly different. From this, it can be confirmed that the deterioration of the battery 53 is progressing rapidly. Note that the threshold value can be, for example, 1.5 times the previous value. For example, when there is a change equal to or greater than such a threshold value, it may be determined that a sudden change has occurred.

[0103] In the example shown in FIG. 32, the change in the length of "the time from the start of charging the battery 53 until the terminal voltage reaches a predetermined voltage" at a certain temperature is observed, but the example does not have to be limited to this. For example, regression lines may be compared (see FIG. 33). However, this is applicable when the slopes of the regression lines for each year are similar and the intercepts are all different. Also, the same thing can be done even when a specific area is set using a specific area generation means instead of using a regression line (see FIG. 34).

[0104] In the above example, the change toward deterioration is illustrated, but the change toward abnormality may also be considered as a sudden change that may occur. (See FIG. 35(a)). In the example shown in FIG. 35, the arrival time increases at approximately the same pace from the first to third years, but the change in arrival time from the third to fourth years is significantly larger than before. It is also considered that the regression line or the specific area changes toward the deterioration judgment area every year due to the use of the battery 53. Here, if the abnormality judgment area is fixed, the distance from the abnormality judgment area increases every year, and even if the arrival time suddenly slows down, it may not reach the abnormality judgment area and be judged as normal. Therefore, the abnormality judgment area may also be made to change according to the regression line or the specific area. (See FIG. 35(b)).

[0105] As can be seen from Figure 36, capacity does not decrease evenly each year, and the range of change in capacity over a unit period usually changes gradually. However, a sudden increase in the range of this change is due to the occurrence of some kind of problem. In particular, if such an event occurs before the deterioration judgment region or abnormality judgment region is reached, it can be said to be a sign that some kind of problem has occurred that is not expected in a normal product.

[0106] As can be understood from these descriptions, it is preferable to configure the system to include a sudden change determination means which acquires voltage behavior information and data from the external information measurement unit at predetermined intervals, and determines that a problem has occurred when a change in the acquired numerical value, or a change in a predetermined numerical value derived using the acquired numerical value, exceeds a predetermined value.

[0107] Also, a variation width determination means may be provided that can determine deterioration, etc. by comparing the difference between the maximum and minimum values ​​in measurements over a unit period. In Fig. 37, an example is shown in which a specific area is set using a specific area generation means, and the difference between the maximum and minimum values ​​of this specific area is observed by the variation width determination means.

[0108] Whether or not a problem has occurred may be determined based on whether the difference between the maximum and minimum values ​​in a specific area exceeds a threshold value, or based on the rate of change in the difference between the maximum and minimum values ​​in a specific area (see FIG. 38). For example, the difference between the values ​​in the n-2th year and the n-1st year is compared with the difference between the values ​​in the n-1st year and the nth year, and if the latter becomes extremely large, it is determined that a problem has occurred even if the threshold value has not been reached. The battery degradation determination system may be configured to output a recommendation to replace battery 53 when it is determined that a problem such as degradation has occurred.

[0109] Incidentally, it is preferable to store the voltage behavior information and external measurement information under defined usage conditions, such as the start and end of use and the number of hours of discharge current. This is because problems may occur in determining the stored data when the usage conditions differ. Therefore, in the embodiment, when the operating method of the battery 53 is changed, the usage conditions of the storage battery can be recognized. Also, data can be stored for each recognized usage condition. Furthermore, a usage condition determination means is provided that enables a determination to be made based on the accumulated data of the battery 53 organized according to the usage condition.

[0110] A judgment is made to select accumulated data that corresponds to the usage conditions of the battery 53 from the measurement data (for example, in the example shown in FIG. 39, conditions A to C). By comparing the selected past data with the latest data of the battery 53 to be judged, it becomes possible to respond to changes in characteristics due to conditions. In other words, by accumulating accumulated data according to the usage conditions, it is possible to change the judgment conditions according to the usage conditions, thereby suppressing the occurrence of errors due to differences in usage conditions.

[0111] As can be understood from these descriptions, it is preferable that the usage conditions of battery 53 be memorizable, and the accumulated data include voltage behavior information and data measured by the external information measurement unit for a predetermined period for each usage condition of battery 53, and that a judgment can be made based on judgment conditions according to the usage conditions of battery 53.

[0112] Although the present invention has been described above by taking the embodiment as an example, the present invention is not limited to the above embodiment and can be embodied in various forms. For example, the calculation formula may be obtained from a method other than a regression line or a regression surface. [Explanation of symbols]

[0113] 53 Battery 551 Storage section 552 Judgment condition setting section 553 Arithmetic section 554 Output section

Claims

1. A terminal voltage detection unit capable of measuring a terminal voltage of a battery; an external information measuring unit capable of measuring one of pieces of information that affect the behavior of the terminal voltage when the battery is charged or discharged; A storage unit capable of storing data measured by the external information measurement unit; a judgment condition setting unit capable of setting judgment conditions based on information in the storage unit; a calculation unit capable of performing calculations for making a judgment based on the judgment conditions set by the judgment condition setting unit; Equipped with The storage unit, The results obtained by the measurement The time it takes for the terminal voltage to reach a specified voltage set below the maximum voltage from the start of charging, The voltage drop at the end of the battery charge, The voltage drop at the beginning of the battery discharge, The time it takes for the terminal voltage to reach a specified voltage after the battery starts discharging. The voltage rise value at the end of the battery discharge, and data measured by an external information measuring unit for a predetermined period of time. The judgment condition setting unit is capable of creating judgment conditions for the battery based on the accumulated data, The calculation unit is a battery deterioration determination system that can determine battery deterioration by comparing judgment conditions created based on accumulated data with newly measured voltage behavior information and data from the external information measurement unit.

2. The judgment condition setting unit is 2. The battery deterioration determination system according to claim 1, wherein the determination conditions can be set based on the correlation between the voltage behavior information contained in the stored data and a plurality of types of data measured by the external information measurement unit.

3. The data measured by the external information measurement unit in the stored data includes information regarding temperature, The judgment condition setting unit is Based on the accumulated data, a formula is derived that expresses the correlation between temperature and voltage behavior information. It is possible to set a degradation diagnosis region in a range where the value is smaller than the calculated voltage behavior value obtained by inputting the temperature into the derived calculation formula by a predetermined amount or more, and to set an abnormality diagnosis region in a range where the value is larger than the calculated voltage behavior value by a predetermined amount or more. Or, It is possible to set a degradation diagnosis region in a range where the value is greater than the calculated voltage behavior value obtained by inputting temperature into the derived calculation formula by a predetermined amount or more, and to set an abnormality diagnosis region in a range where the value is smaller than the calculated voltage behavior value by a predetermined amount or more. year, The deterioration diagnosis area can be used to determine whether the battery has deteriorated, and the abnormality diagnosis area can be used to determine whether an abnormality has occurred in the battery.

3. The battery deterioration determination system according to claim 1 or 2.

4. An accumulated data collection period during which accumulated data is collected, and a judgment period during which a battery judgment condition can be created and a judgment can be made based on the accumulated data obtained during the accumulated data collection period are set, 2. The battery deterioration determination system according to claim 1, further comprising an accumulated data collection time determination means for providing an abnormal deterioration determination condition used during the accumulated data collection period separately from a determination condition used during the determination period.

5. The battery deterioration determination system of claim 1, further comprising a specific area generation means for setting a specific area having a two-dimensional or three-dimensional extent from accumulated data having voltage behavior information and data measured by an external information measurement unit for a predetermined period of time.

6. Acquires voltage behavior information and data from an external information measurement unit at predetermined intervals; The battery deterioration determination system of claim 1, further comprising a sudden change determination means for determining that a problem has occurred when a change in an acquired numerical value or a change in a predetermined numerical value derived using the acquired numerical value becomes greater than a predetermined value.

7. The battery usage conditions can be stored, The stored data includes voltage behavior information and data measured by an external information measurement unit for a predetermined period for each battery use condition, 2. The battery deterioration determination system according to claim 1, wherein the determination can be made under a determination condition corresponding to a usage condition of the battery.

8. an output unit capable of outputting to an outside the information that the battery is degraded and the information that an abnormality is occurring in the battery; The number of times that newly measured voltage behavior information and data from the external information measurement unit must fall within the deterioration diagnosis area before the output unit outputs information that the battery is deteriorating to the outside is smaller than the number of times that newly measured voltage behavior information and data from the external information measurement unit must fall within the deterioration diagnosis area. The number of times that newly measured voltage behavior information and data from the external information measurement section must fall within the abnormality diagnosis range before the output section outputs information that an abnormality has occurred in the battery to the outside is The battery deterioration determination system according to claim 3, wherein the battery deterioration determination system can be set to be less than the predetermined threshold value.

9. A terminal voltage detection unit capable of measuring a terminal voltage of a battery; a current measuring unit capable of measuring a charging current or an integrated current to a battery; an external information measuring unit capable of measuring one of pieces of information that affect the behavior of the terminal voltage when the battery is charged or discharged; A storage unit capable of storing data measured by the external information measurement unit; a judgment condition setting unit capable of setting judgment conditions based on information in the storage unit; a calculation unit capable of performing calculations for making a judgment based on the judgment conditions set by the judgment condition setting unit; Equipped with At least the terminal voltage, the integrated current, and the data measured by the external information measuring unit are stored in the memory unit; the determination condition setting unit is capable of setting a determination condition using at least information on the terminal voltage and the integrated current stored in the storage unit and the data measured by the external information measurement unit; The calculation unit is a battery deterioration determination system that can determine battery deterioration by comparing the determination conditions created based on accumulated data with the newly measured terminal voltage, integrated current, and data from the external information measurement unit.

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