JP2001250590A - Method for deciding deterioration of storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for deciding deterioration of a storage battery, capable of deciding deterioration by maintaining the storage battery in a usable state, without requiring a discharging test, and is capable of reducing maintenance cost. SOLUTION: Internal resistance of a plurality of cells comprising the storage battery are measured, and each of the cells having a value of 0.79 mΩ, which is a resistance value of deciding criteria, or lower is classified as a satisfactory cell. A ratio (%) of satisfactory cells obtained from the number of good cells and the number of total cells, and a capacity of the storage battery is estimated, based on the ratio (%) by using conversion graphs, etc., and deterioration is decided. Since conventional discharging tests are not performed, therefore decision of the deterioration of the storage battery can be performed by maintaining a usable state as an emergency power source. Then by measuring internal resistance of each cell, only considerably deteriorated cells can be selected and replaced, maintenance costs can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining deterioration of a storage battery, for example, a backup of various uninterruptible power supplies (CVCFs) for plants, off-site or equipment, and a control power supply for a substation or the like. The present invention relates to a method for determining deterioration of a storage battery used as a power supply (emergency power supply).

[0002]

2. Description of the Related Art Storage batteries are widely used as backup power sources during power outages. The function required of such a storage battery is to reliably supply power to a load for a required time when a power failure occurs, and this power supply capability is generally referred to as capacity.

[0003] This capacity gradually decreases as the service life of the storage battery increases, but there is a large difference depending on the installation environment and usage conditions. If the capacity of the installed storage battery is low, it will not be useful in an emergency, so the management of the capacity of the storage battery is a very important matter.

Therefore, conventionally, a capacity is estimated by connecting a simulated load equivalent to a rated load to the storage battery, discharging the storage battery, and measuring a discharge time until the discharge end voltage is reached (discharge test). The deterioration state of the storage battery was determined.

[0005]

However, when the deterioration state is confirmed by a discharge test, the storage battery must be recharged after discharging, so that the storage battery cannot be used during charging and does not function as an emergency power supply. There is a problem.

Japanese Unexamined Patent Publication (Kokai) No. 2-304876 discloses a method for judging deterioration that requires measuring the internal resistance of a storage battery. However, according to this method, since the internal resistance of the entire storage battery is measured,
When the storage battery is composed of a plurality of unit cells (cells), it is not possible to specify a cell that increases the overall internal resistance. For this reason, when it is determined that the storage battery is deteriorated, the entire storage battery must be replaced, which is uneconomical. This problem also occurs in a method of determining deterioration by only the above-described discharge test.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of determining the deterioration of a storage battery, which can determine the deterioration state of the storage battery while maintaining the usable state without requiring a discharge test, and can reduce the maintenance cost.

[0008]

According to the first aspect of the present invention, the internal resistance of a plurality of cells (cells) constituting a storage battery is measured, and the capacity of the storage battery is estimated from the measured internal resistance. This is a method of determining the deterioration of the storage battery, which determines the deterioration state of the storage battery based on the result. In such a method, at the installation site of the storage battery, it is only necessary to measure the internal resistance of each cell, so that there is no need to perform a conventional discharge test. Therefore, the deterioration of the storage battery can be determined while maintaining the storage battery in a usable state as an emergency power supply. In addition, since the internal resistance of all the cells constituting the storage battery is measured, in the storage battery determined to be deteriorated due to insufficient capacity, only the cell having a large internal resistance need be replaced, and the maintenance cost can be reduced. I can do it.

According to a second aspect of the present invention, there is provided a method for determining deterioration of a storage battery according to the first aspect, wherein the internal resistance is measured by a four-terminal method. (Especially the probe) and the influence of the contact resistance between the cells are reduced so that a more accurate resistance value can be measured.

According to a third aspect of the present invention, in the storage battery deterioration judging method according to the first or second aspect, the storage battery is applied to a cathode absorption sealed lead storage battery.

According to a fourth aspect of the present invention, a plurality of cells constituting a storage battery are discharged at a constant current, the capacity of each cell is estimated from the voltage of each cell after discharging for a predetermined time, and these cells are estimated. This is a method of estimating the capacity of the storage battery from the estimated capacity and determining the state of deterioration of the storage battery based on the estimation result. Here, the “predetermined time” is, for example, a time of several seconds to several minutes, and is a time that is much shorter than the time required to reach the discharge end voltage. In such a method, for example, a set of a plurality of cells connected in series is connected, a discharging load is connected thereto, and the cells are discharged for a predetermined time, and the voltage of each cell during the discharging is changed in real time. It is sufficient to measure and record, again, it is not necessary to discharge until the end voltage unlike the conventional one, and by replacing only the cell with a small voltage and remarkable deterioration,
The above object is achieved. The charging time for the discharged amount does not matter much because the discharging time is short.

According to a fifth aspect of the present invention, in the storage battery deterioration judging method according to the fourth aspect, the storage battery is applied to one of a lead storage battery, an alkaline battery, a nickel cadmium battery, a nickel hydride battery, and a lithium ion battery. is there.

According to a sixth aspect of the present invention, in the storage battery deterioration judging method according to any one of the first to fifth aspects,
In estimating the capacity of the storage battery, the measured internal resistance of the cell or the estimated capacity of the estimated cell is classified according to a predetermined criterion value, and a specific classification classified based on the criterion value is performed. This is a method for determining the deterioration of a storage battery, which is estimated based on the ratio of the number of cells and the number of all cells.

The invention according to claim 7 is a method of judging the deterioration of a storage battery, wherein the capacity of the storage battery is estimated based on the measured internal resistance of the single battery or the average of the estimated estimated capacity of the single battery.

The invention according to claim 8 is a method for judging the deterioration of a storage battery in which the capacity of the storage battery is estimated based on the measured internal resistance of the battery or the standard deviation of the estimated capacity of the battery. .

According to a ninth aspect of the present invention, in estimating the capacity of the storage battery, a method of determining deterioration of the storage battery, wherein the capacity is estimated based on the measured internal resistance of the cell or the average deviation of the estimated capacity of the cell. It is.

In each of the above-described methods, the correlation between each of the ratio, the average, the standard deviation, and the average deviation and the capacity of the storage battery may be obtained in advance. The capacity can be easily and easily estimated in the light.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] As shown in FIG. 1, a method for judging the deterioration of a storage battery according to the first embodiment is as follows. First, as shown in FIG. For the battery (MSE300), the internal resistance of, for example, 192 unit cells (hereinafter, referred to as cells) constituting the storage battery is measured by a four-terminal method or the like.

Next, as shown in the bar graph of FIG.
Each cell is stratified by an internal resistance of 1 mΩ width, and the number of cells for each resistance width is obtained. Then, since the cell deterioration is smaller as the internal resistance is smaller, cells with an internal resistance of 0.79 mΩ or less are classified as “good” cells, and cells with 0.80 to 0.99 mΩ are classified as “low deterioration” cells. , 1.00 mΩ or more are classified as “deteriorated” cells. 0.79 mΩ or less, which is the internal resistance value of a cell classified as good, is the criterion (resistance) value of the present invention. In the present embodiment, cells outside the determination reference resistance value are classified into small deterioration and large deterioration.
These classifications may be performed as needed, and can be omitted.

Furthermore, the number of good cells (163) within the judgment reference resistance value with respect to the total number of cells (192)
Is determined as a ratio of good cells. In the present embodiment, the ratio of good cells is (163 ÷ 192) × 1.
00 = 85%.

Thereafter, using the conversion graph shown in FIG.
Estimate the capacity of the storage battery. In the present embodiment, the ratio of good cells of the storage battery to be estimated is 85%.
According to the conversion graph, 63% corresponding to the 85% is the estimated capacity of the storage battery. Thus, the estimation of the capacity of the storage battery is completed.

Here, as shown in FIG. 3, the conversion graph of FIG. 4 shows a total of six sets of storage batteries (according to MSE300 and MSE400: JIS) of two types (separate from the storage battery to be estimated). The ratio of good cells of the storage battery) and the actual capacity obtained by the discharge test are created as a database. At this time, the ratios and capacities are obtained by collecting data in advance to create a conversion graph. In particular, the ratios can be obtained by performing the same procedure as described above. Note that the number of storage batteries for creating the conversion graph is not limited to six sets, and the more batteries are preferable.

Finally, in order to determine the state of deterioration of the storage battery, the above-described estimated capacity of the storage battery is compared with a lower limit for determining the state of deterioration. Here, the lower limit value is set in advance to a predetermined value depending on the purpose of use and scale of the storage battery. Here, for example, assuming that the lower limit is set to 70%, the estimated capacity of the storage battery in this embodiment is 6%.
Since it is 3%, the capacity of the storage battery is determined to be insufficient and deteriorated. Thus, the determination of the deterioration state of the storage battery is completed.

If the storage battery is in a deteriorated state and it is determined that the cell needs to be replaced, the degree of deterioration (internal resistance) is determined, for example, by replacing the cell with the larger deterioration and then small deterioration. Are exchanged in order from the cell having the largest value. At this time, since the ratio of good cells is increased by replacing the deteriorated cells, this replacement work is performed until the estimated capacity reaches the lower limit of 70% or more (about 90% or more of good cells). It is not necessary to replace all cells.

According to this embodiment, the following effects can be obtained. (1) In estimating the capacity of the storage battery, at the installation site of the storage battery, it is only necessary to measure the internal resistance of each cell constituting the storage battery, and there is no need to perform a discharge test involving recharging. Therefore, the deterioration of the storage battery can be determined while maintaining the storage battery in a state where it can be used as an emergency power supply, and the reliability of the emergency power supply can be improved.

(2) Since a discharge test is unnecessary, discharge and recharge can be made unnecessary, and complicated work such as connection of a simulated load can be omitted, so that the time required for storage battery maintenance can be greatly reduced. .

(3) Since the reference resistance value is 0.79 mΩ or less (less than 0.80 mΩ), which is the internal resistance value of the cell, there is no fear that the number of cells classified as good is increased too much. For this reason, since there is no possibility that the ratio of good cells will increase, it is possible to prevent the capacity of the storage battery from being estimated to be excessively large, and to improve the credibility of the capacity estimation result.

(4) According to the present embodiment, since the internal resistances of all the cells constituting the storage battery are measured, in the case of a storage battery with insufficient capacity, only the cells whose internal resistance is large and whose deterioration is remarkable need be replaced. Maintenance costs can be greatly reduced compared to the conventional case where the entire storage battery has to be replaced.

(5) At this time, the cells outside the judgment reference resistance are classified into small deterioration and large deterioration. Therefore, when replacing the cells, the cells corresponding to the large deterioration may be replaced in order from the cell corresponding to the large deterioration. Can be easily and accurately performed. In addition, by recording the cells with small deterioration, it is possible to preliminarily estimate the necessity of replacement at the next maintenance, so that the estimation of how many new cells will be required can be made more accurate. Can be done.

(6) The lower limit is set so that cells are replaced when the estimated capacity of the storage battery is smaller than 70% (the ratio of good cells is about 90%). And the storage battery can be reliably maintained in a state where the capacity is sufficient.

(7) Since the internal resistance of all cells is measured, it is not necessary to perform a destructive inspection by extracting a sample from a plurality of cells, so that the deterioration state of each cell and thus the entire storage battery can be grasped more accurately. can do.

(8) Since the four-terminal method is used for measuring the internal resistance of each cell, the influence of the probe of the measuring instrument and the contact resistance between cells can be reduced, and a more accurate resistance value can be measured.

(9) When obtaining the capacity of the storage battery from the ratio of good cells, the conversion graph prepared by collecting data in advance is used, so that the capacity can be quickly and easily estimated.

(10) In the past, storage batteries were maintained based on the age of the storage batteries and the like, but the maintenance could not be performed efficiently because the usage years differ for each storage battery. However, according to the present embodiment, the estimation of the storage batteries is performed intensively for all the storage batteries, and as a result, only the deteriorated cells having a large internal resistance need to be replaced, so that the maintenance work can be periodically and efficiently performed. it can.

[Second Embodiment] In the storage battery deterioration determination method according to the second embodiment of the present invention, when estimating the capacity of the storage battery, as in the first embodiment, all the cells constituting the storage battery are used. The internal resistance is measured and classified into “good”, “low deterioration”, and “high deterioration” according to the internal resistance value of each cell. Further, in this embodiment, the average internal resistance of each cell is obtained, and thereafter, the capacity of the storage battery is estimated using the conversion graph shown in FIG. However, the classification of each cell can be omitted as long as a cell that needs to be replaced can be identified from its internal resistance, and it is not always necessary to classify according to the deterioration state.
The same applies to third and fourth embodiments described later.

Here, the conversion graph of FIG. 5 has two types (based on MSE300 and MSE400: JIS) as in the first embodiment.
In a total of 9 sets (N = 9) of storage batteries (storage batteries different from the storage battery to be estimated), the average internal resistance of all cells constituting each storage battery and the actual capacity obtained by a discharge test are created as a database. The internal resistance value and capacitance are obtained by collecting data in advance to create a conversion graph.

According to this conversion graph, there is a correlation function between the average internal resistance (x) and the capacity (y) as y =-.
118.84x + 155.25, and a correlation with a correlation coefficient of 0.73 is established. Therefore,
If the average internal resistance of all the cells of the storage battery to be estimated is made to correspond to the conversion graph, the capacity can be easily estimated. Then, as a result of the estimation, when the capacity is smaller than the predetermined lower limit value, it is determined that the storage battery is in a deteriorated state, and the cells may be replaced as necessary in order from the cell having the larger internal resistance.

Also in this embodiment, at the site where the storage battery is installed, it is only necessary to measure the internal resistance, and it is not necessary to perform a discharge test involving recharging, and a discharge test is not necessary. The effect of 4) can be similarly obtained, and the object of the present invention can be achieved. Further, with the same configuration as the first embodiment, the above-described (2), (5), (7) to (10)
Can be obtained similarly.

[Third Embodiment] In the storage battery deterioration judging method according to the third embodiment of the present invention, when estimating the capacity of the storage battery, the internal resistances of all the cells constituting the storage battery are measured. The standard deviation is obtained based on the internal resistance and the average internal resistance of the cell, and thereafter, the capacity of the storage battery is estimated using the conversion graph shown in FIG. The standard deviation is given by the following equation.

[0041]

(Equation 1)

Here, in the conversion graph of FIG. 6, similarly to the second embodiment, a total of nine sets (N = 9) of storage batteries (storage batteries different from the storage battery to be estimated) constitute each storage battery. The standard deviation of the internal resistance of all cells and the actual capacity of the discharge test were created as a database, and the standard deviation and capacity were also obtained by collecting data in advance to create a conversion graph. Things.

According to this conversion graph, the standard deviation (x)
And y = −393.9x + 11
4.79, and a correlation with a correlation coefficient of 0.77 is established. Therefore, if the standard deviation of the internal resistance of all the cells of the storage battery to be estimated is made to correspond to the conversion graph, the capacity can be easily estimated.
Then, as a result of the estimation, when it is determined that the capacity is smaller than the lower limit value and the battery is in a deteriorated state, the cells may be replaced as necessary in order from the cell having the larger internal resistance.

In this embodiment, the same effect as in the second embodiment can be obtained, and the correlation coefficient is closer to 1 than in the second embodiment, so that the capacity is estimated based on the average internal resistance. Also, there is an effect that more reliable estimation can be performed.

[Fourth Embodiment] In the storage battery deterioration judging method according to the fourth embodiment of the present invention, when estimating the capacity of the storage battery, the internal resistances of all the cells constituting the storage battery are measured. An average deviation is determined based on the internal resistance and the average internal resistance of the cell, and thereafter, the capacity of the storage battery is estimated using a conversion graph as conversion means shown in FIG. The average deviation is given by the following equation.

[0046]

(Equation 2)

Here, the conversion graph of FIG.
Similar to the embodiment, the data is obtained by collecting data in advance for a total of 9 sets (N = 9) of storage batteries (storage batteries different from the storage battery to be estimated).
Between the average deviation (x) and the capacity (y), y = −56
There is a relationship of 9.18x + 118.73, and a correlation with a correlation coefficient of 0.79 is established. Therefore, it is possible to easily estimate the capacity from this conversion graph and determine the deterioration state, and to recover the capacity,
The cells may be replaced in order from the cell having the larger internal resistance.

In this embodiment, the same effects as those of the second and third embodiments can be obtained, and the correlation coefficient is closer to “1” than in the third embodiment. There is an effect that the capacity can be more accurately estimated than in the case of estimating the capacity, and the deterioration state can be reliably determined.

[Fifth Embodiment] In the storage battery deterioration judging method according to the fifth embodiment of the present invention, the capacity of the storage battery is estimated based on the correlation between the average deviation and the capacity as in the fourth embodiment. 8 in that the conversion graph shown in FIG. 8 is used. That is, the conversion graph in the present embodiment shows the correlation by format, and the correlation coefficient in one format (MSE300) and the other format (MSE400) are both 0.9 or more. It is recognized that the value is remarkably higher (see the graph for the equations indicating the number of data and the correlation function). Therefore, in the present embodiment, by properly using the conversion graph according to the type of storage battery to be estimated,
There is an effect that the estimation accuracy can be greatly improved.

[Sixth Embodiment] A method for judging deterioration of a storage battery according to a sixth embodiment of the present invention is as follows. FIG.
As shown in the figure, in a normal state where the storage battery is connected to the existing equipment, of the plurality of cells constituting the storage battery, an arbitrary number of cells connected in series is set as one set, and both ends of the cell in this set are connected. Connect a discharge resistor as a discharge load. In addition, wiring for voltage measurement is provided for each cell, and each wiring is connected to a measuring machine so that data from the measuring machine can be processed by a personal computer (PC).

Next, the switch in the discharge circuit is turned on to discharge the cells in the set with a constant current, the voltage of each cell being discharged is measured in real time, for example, for one minute, and the voltage during this period is stored in the PC. Let it. In addition, as the storage battery, in addition to the lead storage battery as in the first to fifth embodiments, any of an alkaline battery, a nickel-cadmium battery, a nickel-metal hydride battery, and a lithium ion battery may be used. In the present embodiment, an alkaline battery is used.

Here, the graph of FIG. 10 shows the voltage change during the discharge test of the cell having no or little deterioration,
In addition, a voltage change at the time of a discharge test of a cell which is recognized to be deteriorated is shown. As is clear from this graph, there are cells whose voltage drops significantly with discharge. It is known that such a cell is a deteriorated cell. FIG. 11 shows the voltage at the time when each cell was discharged for 1 minute, and the capacity confirmed by an actual discharge test. The graph in FIG. 12 shows the correlation between the voltage and the cell capacity. The correlation function obtained from the cell capacity and cell voltage in FIG. 11 is stored in the PC.

Therefore, the voltage data of each cell from the measuring instrument shown in FIG. 9 is processed in the PC, and the capacity of each cell is estimated based on the correlation function. These estimated capacities are further stored in the PC. Thereafter, the PC calculates the average, the standard deviation, or the average deviation of the estimated capacities of all the cells constituting the storage battery, and stores this.

As in the second to fifth embodiments, the correlation (function) between the capacity of the entire storage battery and the average or standard deviation of the estimated capacities of all cells or the average deviation is determined in advance and the PC From the correlation, the capacity of the storage battery is automatically estimated by the PC based on the average, standard deviation, or average deviation of the estimated capacity actually calculated, and as a result of the estimation, the capacity becomes a predetermined value. The PC automatically determines whether the value is smaller or larger than the lower limit, and displays the result on a display or the like. At this time, when it is determined that the storage battery is in a deteriorated state, cells having a lower voltage (smaller estimated capacity) may be replaced in order so that the capacity of the storage battery exceeds the lower limit. The cell number is displayed on the display of the PC as to whether or not it should be replaced. May be displayed. Such processing can be easily implemented by incorporating software such as a comparison operation program into the PC.

In this embodiment as well, the operation can be performed while the storage battery can be used as an emergency power source, and only the cells having a low voltage after discharging need to be replaced. Therefore, no labor or cost is required for maintenance work. In addition, it is necessary to charge the battery after discharging it. However, since the discharging time is as short as one minute, the charging can be completed in a short time by performing the equal charging of the cell. The non-functioning time can be shortened, and the reliability as an emergency power supply can be improved. Therefore, the above-mentioned object of the present invention can be achieved.

It should be noted that the present invention is not limited to the above-described embodiment, but includes other configurations capable of achieving the object of the present invention, and the following modifications are also included in the present invention.
For example, the conversion graph in the first to fourth embodiments is 2
Although it is created based on the storage battery data of the types, a conversion graph for each type may be created.
By doing so, a conversion graph corresponding to the type of the storage battery to be estimated can be used as in the fifth embodiment, and the reliability of the estimated capacity is further improved.

Further, for example, the conversion graph in the first embodiment is obtained by plotting the data shown in FIG. 3, but when the conversion graph is created, the storage battery such as the ambient temperature is used. A correction coefficient may be set in consideration of the installation environment and the like, and may be created in consideration of the correction coefficient. The same applies to conversion graphs in other embodiments.

In the first to fifth embodiments, the conversion graph is used. However, the present invention is not limited to this, and may be configured by software such as a comparison operation program.
That is, as in the sixth embodiment, by using a PC or the like in which various software such as a comparison operation program is incorporated, the classification of good cells, small deterioration, large deterioration, etc. Calculation of average internal resistance, calculation of standard deviation, calculation of average deviation, and even estimation of capacity,
It may be possible to automatically execute by simply inputting the internal resistance of each cell, or from a device that measures the internal resistance to a PC
It is a matter of course that data may be collected in advance and various processes can be automatically performed immediately after the measurement of the internal resistance.

Further, when the capacity of each cell is estimated as in the sixth embodiment, the estimated capacity is classified according to a predetermined criterion value, and the specific cell of the specific cell classified based on the criterion value is classified. The capacity of the entire storage battery may be estimated based on the ratio of the number of cells and the number of all cells, and such a case is included in the invention of claim 6.

[0060]

As described above, according to the present invention,
There is no need to perform a conventional discharge test, and it is possible to estimate the capacity of the storage battery while maintaining it in a usable state.
There is an effect that maintenance costs can be reduced by replacing only the cells that are significantly deteriorated.

[Brief description of the drawings]

FIG. 1 is a diagram showing a measurement result of an internal resistance of a cell performed by a deterioration determination method according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a bar graph for explaining the cell classification.

FIG. 3 is a diagram showing data for obtaining conversion means of the embodiment.

FIG. 4 is a diagram showing a conversion graph as the conversion means.

FIG. 5 is a diagram showing a conversion graph used in a deterioration determination method according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a conversion graph used in a deterioration determination method according to a third embodiment of the present invention.

FIG. 7 is a diagram showing a conversion graph used in a deterioration determination method according to a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a conversion graph used in a deterioration determination method according to a fifth embodiment of the present invention.

FIG. 9 is a diagram illustrating voltage measurement performed by a deterioration determination method according to a sixth embodiment of the present invention.

FIG. 10 is a graph showing a relationship between a discharge time and a voltage of a unit cell in the sixth embodiment.

11 is a diagram illustrating voltage and capacity of a unit cell based on the graph of FIG.

FIG. 12 is a diagram showing a graph serving as a basis for estimating the capacity of a unit cell in the sixth embodiment.

Claims (9)

[Claims] An internal resistance of a plurality of cells constituting a storage battery is measured, a capacity of the storage battery is estimated from the measured internal resistance, and a deterioration state of the storage battery is determined based on the estimation result. Characteristic method of determining deterioration of storage battery. 2. The method for determining deterioration of a storage battery according to claim 1, wherein the internal resistance is measured by a four-terminal method. 3. The method for determining deterioration of a storage battery according to claim 1, wherein the storage battery is a sealed lead storage battery of a cathode absorption type. 4. A method for discharging a plurality of cells constituting a storage battery at a constant current, estimating the capacity of each cell from the voltage of each cell after discharging for a predetermined time, and calculating the capacity from the estimated capacity of these cells. A method for determining deterioration of a storage battery, comprising estimating a capacity of the storage battery and determining a deterioration state of the storage battery based on the estimation result. 5. The storage battery deterioration determination method according to claim 4, wherein the storage battery is any one of a lead storage battery, an alkaline battery, a nickel-cadmium battery, a nickel-metal hydride battery, and a lithium-ion battery. Deterioration determination method. 6. The method for determining deterioration of a storage battery according to claim 1, wherein when estimating the capacity of the storage battery, the internal resistance of the measured single battery or the estimated value of the single battery is determined. Deterioration of the storage battery, wherein the estimated capacity is classified based on a predetermined criterion value, and estimated based on the ratio of the number of specific cells categorized based on the criterion value to the total number of cells. Judgment method. 7. The method for determining deterioration of a storage battery according to claim 1, wherein when estimating the capacity of the storage battery, the internal resistance of the measured single battery or the estimated single battery of the storage battery is determined. A method for judging deterioration of a storage battery, wherein the method is performed by estimating an average of estimated capacities. 8. The method for determining deterioration of a storage battery according to any one of claims 1 to 5, wherein estimating the capacity of the storage battery includes: A method for judging deterioration of a storage battery, wherein the method is based on a standard deviation of an estimated capacity. 9. The method for determining deterioration of a storage battery according to any one of claims 1 to 5, wherein estimating the capacity of the storage battery includes: A method for determining deterioration of a storage battery, comprising estimating a capacity based on an average deviation of an estimated capacity.