JP3364049B2 - Battery life evaluation method and device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead battery life evaluation test apparatus. The information processing system
It is necessary to provide a backup battery in order to retain the accumulated information in the event of a power failure, and maintain it so that the minimum required capacity can always be obtained. To this end, it is essential to improve the reliability of the lead battery used as a backup battery, and a technique for accurately evaluating the life of the lead battery is required. In particular, it is known that in a sealed lead-acid battery, when the deterioration of the positive electrode or the decrease of the electrolytic solution goes beyond a certain value, the capacity of the battery rapidly decreases. Therefore, even if a battery having a sufficiently large capacity is provided in anticipation of deterioration, it does not make much sense in terms of improving reliability. On the other hand, there is a great need to accurately predict the battery life in order to properly manage the replacement time.

[0002]

2. Description of the Related Art In a conventional life evaluation test, the deterioration of a lead battery is accelerated by raising the environmental temperature,
The battery life was evaluated by measuring the change in capacity. For example, in a high temperature environment that exceeds the normal operating temperature, multiple sample batteries arbitrarily extracted from the product under test are trickle charged for different times, and the sample battery whose capacity has dropped to the minimum required capacity is detected. By doing so, the service life Lt in this high temperature environment can be obtained, and the service life Ls of the battery in the actual use environment can be predicted based on this service life Lt. In addition,
The capacity of each sample battery is measured by measuring the voltage between the terminals of the battery while discharging a constant current, and the time required for the voltage between the terminals to drop to a specified threshold Tm and the constant current.
It can be calculated from Ic.

Here, there is a correlation based on the Arrhenius theorem between the increase in environmental temperature and the shortening of battery life, and the chemical reaction is doubled every time the environmental temperature is increased by 10 degrees. Therefore, it is known that the battery life Lt in the test environment is expressed as shown in Equation (1) using the battery life Ls in the normal environment and the normal environment temperature Ts and the test environment temperature Tt. Has been.

[0004]

[Equation 1] Therefore, by substituting the battery life Lt obtained as described above into the equation (1) and transforming the battery life Ls, the battery life Ls in a normal environment can be predicted.

[0005]

When the method of accelerating a chemical reaction by the above-mentioned environmental temperature is applied to the evaluation of the life of a battery, the test environmental temperature should be set in consideration of the heat resistant temperature of the battery case. It is necessary to set restrictions. Therefore, the upper limit of the test environment temperature is about 50 degrees Celsius, and the acceleration obtained in this case is only four times. Therefore, a test period of about 9 months is required to complete the evaluation of the battery, which is expected to have a life of 3 years in an environment of 30 degrees Celsius.

As described above, in the conventional life evaluation method, since it takes a long time to evaluate the life, in the worst case, the product development cannot be completed in time, and the battery may be adopted based on the inaccurate evaluation result. There was a nature. In this case, the battery will deteriorate before the replacement time,
May be useless when really needed,
Efforts to improve reliability were needed.

The deterioration of the battery is originally due to the deterioration of the positive electrode and the decrease of the electrolytic solution. The environmental temperature accelerates deterioration due to these factors, and is merely an indirect factor. Therefore, since the true factor that determines the life of the battery cannot be specified by the life evaluation using the rise of the environmental temperature, the evaluation result cannot be used for the battery development.

It is an object of the present invention to provide a battery life evaluation method and device capable of evaluating the accurate life of a battery according to the factors thereof.

[0009]

FIG. 1 is a diagram showing the principle of the invention of claim 1. In FIG.

According to a first aspect of the present invention, in a battery life evaluation method for evaluating the life of a battery having a structure in which an electrolytic solution is enclosed in a case, the amount of the electrolytic solution and the amount of electricity that the battery can supply, that is, the capacity of the battery, Of the battery, the weight change of the battery is measured over a predetermined period of time, and based on the measurement result, the change in the remaining amount of the electrolytic solution in the battery after the predetermined period is predicted. Based on the evaluation result of the relationship between the amount of the liquid and the capacity of the battery, the time required for the amount of the electrolytic solution to decrease until the battery cannot hold the minimum necessary capacity is calculated. It is characterized in that it is used as an evaluation result of life.

FIG. 2 is a diagram showing the principle of the invention of claim 2. According to a second aspect of the present invention, a constant current is supplied in a battery life evaluation method for evaluating the life of a battery configured to hold a paste containing an electrolytic solution and collect a current by means of a metal grid forming both electrodes. The battery is always charged by the, and at a predetermined time interval, it is determined whether the battery has a predetermined capacity.If the battery has a predetermined capacity, the battery is continuously charged and the battery is If the battery does not maintain the specified capacity, the battery is terminated and the amount of electricity consumed for the electrolysis of water and the inspection of the capacity of the battery during charging is evaluated. Based on the total amount of charging electricity supplied to the battery and the amount of oxidizing electricity consumed to oxidize the positive electrode of the battery, the amount of oxidizing electricity is calculated. On the basis of the trickle charge current value which the battery is supplied in use, for the positive pole of the battery is degraded due to the oxidation reaction, seek time required until impossible holding a predetermined capacity, the life by the cathode degradation It is characterized by making it the evaluation result of.

FIG. 3 is a block diagram of the principle of the battery life evaluation device according to claims 3 to 5. Claim 3
Of the present invention, in a battery life evaluation device for evaluating the life of a battery 101 having a structure in which an electrolytic solution is sealed in a case, a correlation evaluation means 111 for evaluating the correlation between the amount of the electrolytic solution and the capacity of the battery 101; Based on the correlation between the amount and the capacity, the limit liquid amount calculation means 112 for obtaining the limit amount of electrolyte solution that makes it impossible for the battery 101 to supply the minimum necessary amount of the capacity, and the battery 101 of the battery 101 over a predetermined period. A weight measuring unit 113 for measuring a weight change, and an electrolytic solution amount predicting unit 114 for predicting a change in the electrolytic solution amount after a predetermined period based on a measurement result by the weight measuring unit 113, and an electrolytic solution amount predicting unit 114. Based on the prediction result, the life predicting means 1 for predicting a period required until the amount of the electrolytic solution in the battery 101 reaches the limit amount
And 15 are provided.

According to a fourth aspect of the present invention, in the battery life evaluation device according to the third aspect, the correlation evaluation means 111 is used.
Is an individual charging unit 122 that supplies a charging current to each sample battery 121 for a different period with the case of the plurality of sample batteries 121 open, and a capacity measuring unit 123 that measures the capacity of each of the plurality of sample batteries 121. And multiple sample batteries 1
21 Liquid amount measuring means 124 for measuring the amount of each electrolyte
And a correlation extraction unit 125 that extracts a correlation based on the capacities of a plurality of sample batteries 121 and the amount of electrolyte.
It is characterized by having a configuration including.

A fifth aspect of the present invention is the battery life evaluation apparatus according to the third aspect, wherein the weight measuring means 113 is used.
Is a gas generated by electrolyzing water when the battery 101 is placed in a low-humidity environment and a permeated water content measuring unit 126 that measures a weight change due to water permeation from the case and a predetermined charging current is supplied to the battery 101. And a permeated gas measuring means 127 for measuring a change in weight due to permeation from the case.

FIG. 4 is a block diagram showing the principle of the battery life evaluation device according to claims 6 to 8. Claim 6
In the battery life evaluation device for evaluating the life of the battery 102 configured to hold the paste containing the electrolytic solution and collect the electric current by the metal grids forming the both electrodes, the invention described in (1) above continuously determines the battery 102 by a predetermined amount. Continuous charging means 131 for supplying charging current, and battery 1
02, the water replenishing means 132 for replenishing water according to the amount of the electrolyte remaining, and the battery 102 at predetermined time intervals.
Capacity inspecting means 133 for inspecting whether the battery maintains a predetermined capacity, the inspection result by the capacity determining means 133, the charged electricity quantity supplied by the continuous charging means 131, and the water supply means 13.
2 and the amount of water supplied, the oxidative electricity amount calculation means 134 for calculating the oxidative electricity amount spent in the oxidation reaction of the positive electrode of the battery 102, and the charging current supplied to the battery 102 in the actual use state. Based on the value and the value, the positive electrode life evaluation unit 13 that calculates the period required until the amount of oxidizing electricity is supplied to the positive electrode of the battery 102 as the life of the positive electrode.
And 5 are provided.

According to a seventh aspect of the present invention, in the battery life evaluation device according to the sixth aspect, the battery 102 is
It is characterized in that the case holding the paste containing the metal grids of both electrodes and the electrolytic solution is opened.
According to an eighth aspect of the present invention, in the battery life evaluation apparatus according to the sixth aspect, an environment setting unit 136 for setting an environment of high humidity to a degree that suppresses the phenomenon of water permeating from the case of the battery 102 is provided. Is characterized by.

[0017]

According to the invention of claim 1, the correlation between the amount of the electrolyte and the capacity of the battery and the decrease with time of the amount of the electrolyte of the battery, which is a direct factor of the decrease in the capacity of the battery, are evaluated, and the minimum required amount is evaluated. By obtaining the time required for the amount of the electrolytic solution to decrease to the limit amount that can maintain the limit capacity, the life due to the decrease of the electrolytic solution can be predicted.

According to the second aspect of the present invention, it is possible to obtain the oxidative electricity amount spent to oxidize the metal grid of the positive electrode before the battery cannot maintain the predetermined capacity. The life of the positive electrode itself can be evaluated based on the current. The invention of claim 3 is
Based on the limit liquid amount obtained by the correlation evaluation unit 111 and the limit liquid amount calculation unit 112, and the time change of the electrolytic solution obtained by the weight measuring unit 113 and the electrolytic solution amount predicting unit 114, the life predicting unit 115 By operating, as the life of the battery 101 due to the decrease of the electrolytic solution, the time required for the electrolytic solution to decrease to the limit liquid amount can be obtained.

According to the fourth aspect of the present invention, the electrolytic solution of the plurality of sample batteries 121 is reduced by different amounts by the operation of the individual charging means 122. Therefore, the capacity measuring means 123 and the liquid amount measuring means 124 are provided for each sample. By measuring the capacity of the battery 121 and the amount of the electrolytic solution, the correlation extracting unit 125 can quantitatively evaluate the relationship between the amount of the electrolytic solution and the capacity. In particular, the amount of electrolytic solution is reduced by keeping the case of the sample battery 121 open and supplying the charging current larger than the current value at the time of normal trickle charging to each sample battery 121 by the individual charging means 122. It is possible to accelerate significantly and enable evaluation in a short period.

According to the invention of claim 5, the water permeation amount measuring means 1
26 and the gas permeation amount measuring means 127, it is possible to measure the decrease of the electrolytic solution for each of the more detailed factors and use it for the prediction process of the time change of the electrolytic solution amount. In particular, the moisture permeation amount measuring means 126 can verify the permeation of moisture from the case by a stricter standard by placing the battery 101 in a low humidity environment for measurement.

According to the sixth aspect of the present invention, according to the inspection result by the capacity inspection unit 133, the oxidizing electricity amount calculation unit 134
Based on the amount of electricity and the amount of moisture provided to the battery 102 by the continuous charging unit 131 and the water replenishing unit 132, respectively, the amount of oxidizing electricity spent in the oxidation reaction of the positive electrode of the battery 102 can be directly evaluated. Therefore,
The positive electrode life evaluation means 135 operates based on the amount of oxidized electricity to evaluate the life of the positive electrode of the battery 102 itself.

According to the invention of claim 7, the oxidation reaction of the positive electrode can be greatly accelerated by opening the case of the battery 102 and accelerating the escape of the gas generated by the electrolysis. Therefore, the evaluation period can be shortened. Can be planned.

In the eighth aspect of the present invention, since the environment setting means 136 can prevent the permeation of water from the case of the battery 102, the factor of decreasing the electrolytic solution can be limited to only the electrolysis of water. It is possible to improve the calculation accuracy of the amount of electricity to be oxidized.

[0024]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 5 is a block diagram of an embodiment of the battery life evaluation apparatus according to claims 3 to 5. In FIG. 5, the battery life evaluation device is provided with an electrolyte solution measuring unit 211.
The extrapolation processing unit 212 evaluates a temporal change in the amount of electrolyte of a battery to be tested (hereinafter, referred to as a test battery) corresponding to the battery 101, and also measures the capacity measurement unit 213 and the correlation extraction unit 214. With the configuration, the correlation between the amount of electrolyte and the battery capacity is evaluated, and the life prediction unit 215 predicts the average life of the test battery based on the evaluation results.

The above-mentioned electrolytic solution amount measuring unit 211 corresponds to the weight measuring means 113 described in claim 3,
The extrapolation processing unit 212 corresponds to the electrolytic solution amount predicting unit 114. In the electrolyte solution measuring unit 211,
The weight measuring unit 221a corresponds to the permeated water measuring unit 126 described in claim 5, and is a low humidity environment chamber 222.
The weight of a sample of the test battery (hereinafter, referred to as a sample battery 223a) placed in is measured at regular time intervals and sent to the extrapolation processing unit 212.

While the charging circuit 224 supplies a predetermined charging current to the sample battery 223b,
The weight measuring unit 221b realizes the function of the permeated gas measuring unit 127 described in claim 5 by measuring the weight of the sample battery 223b at every predetermined time, and sends the measurement result to the extrapolation processing unit 212. It is configured to do.

Further, in the extrapolation processing section 212, the measurement value storage section 225 sequentially stores the measurement results by the weight measurement sections 221a and 221b, and sends the collected measurement results to the change rate calculation section 226. Has become. As shown in FIG. 6, the change rate calculation unit 226 plots a time change of the weight reduction amount of each of the electrolyte solutions of the sample batteries 223a and 223b, and each weight reduction amount changes at a constant change rate. Range (reference numeral a in FIG. 6)
Is shown), and the rate of change in that range is obtained. At this time, the change rate calculation unit 22
6, for example, if the reduction amount due to the permeation of water and the reduction amount due to the permeation of gas at each measurement time are summed, the above-mentioned change rate for the total reduction amount is calculated and sent to the electrolytic solution amount prediction unit 227. Good.

Further, the electrolytic solution amount predicting section 227 extrapolates the measurement result for the measuring range shown in FIG. 6 based on this change rate, predicts the change in the electrolytic solution amount over a predetermined period, and determines the life. It is configured to be sent to the prediction unit 215. At this time, the electrolytic solution amount predicting unit 227 needs to predict the change in the electrolytic solution amount at predetermined sample intervals for at least the period given as the design value of the life of the test battery. For example, when the designed value of the life of the test battery is 3 years, the predicted value of the amount of electrolyte solution is calculated at 1-month intervals for a period of about 5 years, and the result is sent to the life prediction unit 215. Good.

Here, as described above, the invention of claim 5 is applied, and the permeation of water and the permeation of gas from the battery case are independently measured, thereby facilitating the isolation of the factors that determine the life. The measurement result can be applied not only to the prediction of the life but also to the design work. Also,
The capacity measuring unit 213 shown in FIG. 5 maintains the discharge current from the sample batteries 232 _{1 to} 232 _n at a constant value by the constant current circuits 231 _{1 to} 231 _n , as in the conventional case, while the voltage measuring unit 233 ₁ to The terminal voltage of each of the sample batteries 232 _{1 to} 232 _n is measured by the 233 _n at a predetermined time interval and is sent to the capacity calculating section 234. In addition, the capacity calculator 234 multiplies the elapsed time until the inter-terminal voltage falls below a predetermined threshold value and the discharge current based on the measurement results by the voltage measuring units 233 _{1 to} 233 _n , and calculates the respective sample batteries. 232 _1-2
The capacity of 32 _n may be obtained and sent to the correlation extraction unit 214.

Further, in FIG. 5, charging circuits 235 ₁ ...
235 _n is configured to supply a charging current to each of the above-described sample batteries 232 _{1 to} 232 _n for a predetermined time in response to an instruction from the charging control unit 236,
Fulfills the function of the individual charging means 122 described in claim 4,
The sample batteries 232 _{1 to} 232 _n are configured to be subjected to the above-described capacity measurement process in a state where the amounts of the electrolytic solutions are reduced to different amounts.

Here, the amount of each electrolyte solution corresponds to various elapsed times in the usage state of the test battery. Therefore, these sample batteries 232 ₁
The function of the correlation evaluation means 111 described in claim 3 is that the correlation extraction unit 214 performs the correlation extraction processing according to the input of the measured values of the capacities and the amounts of the respective electrolytic solutions for ˜232 _n. It is possible to evaluate the correlation between the change in the amount of electrolytic solution and the change in battery capacity over time.

[0033] For example, the correlation extracting unit 214, as shown in FIG. 7, the volume of each sample battery 232 ₁ ~232 _n corresponds to the weight decrease amount of the electrolytic solution is plotted on a graph, these sample points It suffices to obtain an approximate curve that passes through and use it for the processing of the life prediction unit 215 as information indicating the correlation. In the life prediction unit 215 shown in FIG. 5, the limit liquid amount calculation unit 241 corresponding to the limit liquid amount calculation unit 112.
Is the amount of decrease in the corresponding electrolyte solution based on the above-described correlation between the electrolyte solution amount and the capacity in accordance with the input of the minimum required capacity (hereinafter referred to as the standard capacity value) (see FIG. 7). ), The limit weight reduction amount is sent to the life calculation unit 242. Accordingly, the life calculation unit 242
Is the time required to decrease the amount of electrolyte solution in the test battery by the limit weight reduction amount based on the above-mentioned prediction result of changes in the amount of electrolyte solution. You can output it as Ld.

As described above, according to the processing results by the extrapolation processing unit 212 and the correlation extraction unit 214, the limit liquid amount calculation unit 241 and the life calculation unit 242 operate, and the life prediction described in claim 3 is performed. The function of the means 115 can be realized to predict the life of the battery under test due to the reduction of the electrolyte. By comparing the predicted value Ld of the life obtained in this way with the specified life Ls of the battery, a case or a seal for holding the electrolyte of the test battery is necessary to satisfy the specified life Ls of the battery. It is possible to directly evaluate whether or not the performance is satisfied.

Since the decrease of the electrolytic solution depends on the material and structure of the battery case, the method of sealing the case, and the like, the information directly linked to the case itself can be obtained by paying attention to the decrease of the electrolytic solution and evaluating the life. As a result, it is possible to provide the life evaluation result and support the design work and the manufacturing work. Further, in the above-mentioned capacity measuring unit 213, the evaluation environment described in claim 4 is applied to promote evaporation of water in a state in which the case of each of the sample batteries 232 _{1 to} 232 _n is opened, and each of the sample batteries 232 ₁
By continuously charging ~ 232 _n to promote the decrease of the electrolytic solution due to the electrolysis of water, the decrease of the electrolytic solution can be greatly accelerated.

As described above, by accelerating the decrease of the electrolytic solution which is one of the direct factors, it is possible to greatly accelerate the decrease of the battery capacity, which corresponds to the respective sample batteries 232 _{1 to} 232 _n. It is possible to quickly set the capacity decrease corresponding to the period. For example, under the above-mentioned conditions, the amount of electrolyte solution that is equivalent to 3 years in a normal use environment occurs in a period of about 1 to 2 months, so that the time required to evaluate the life of the test battery can be significantly shortened.

Next, a battery life evaluation device according to claims 6 to 8 will be described. FIG. 8 shows a configuration diagram of an embodiment of the battery life evaluation apparatus of claims 6 and 7. In the battery life evaluation apparatus shown in FIG. 8, the charging circuit 251 corresponds to the continuous charging means 131, and is configured to supply a predetermined charging current Ic to the test battery 252 corresponding to the battery 102.

Here, if the invention of claim 7 is applied and the case of the test battery 252 is opened, the gas generated during charging escapes without being reduced to water. The deterioration of the positive electrode due to electrolysis can be greatly accelerated. In addition, the charging circuit 251 is configured to supply the maximum current that can be supplied as the charging current Ic, which can promote the electrolysis of the electrolytic solution as much as possible. As the value of the charging current Ic, a maximum current value in a range in which the electrolytic solution does not jump out of the case or the case itself is deformed may be obtained in advance by an experiment or the like, and this current value may be used.

The water replenishing working section 253 corresponding to the water replenishing means 132 regularly replenishes the test battery 252 with pure water, and the weight measuring section 261 for periodically measuring the weight of the test battery 252. Hydration unit 26
2 and. Also, this hydration unit 2
The amount Wr of pure water replenished by 62 is the replenishment amount holding unit 2
It is stored in 63 and is configured to be used for the processing of the electric quantity calculation unit 254 described later. Further, in FIG. 8, the capacity check unit 255 is the capacity checking means 13 described in claim 6.
3 corresponds to the discharge circuit 264 that periodically discharges the test battery 252 for a certain period of time, a voltage measurement unit 265 that measures the terminal voltage of the test battery 252 that is being discharged, and a voltage measurement result that corresponds to the voltage measurement result. And a capacity determination unit 266 for determining the presence or absence of capacity.

The determination result by the capacity determining unit 266 is
The charging circuit 251 and the rehydration water working unit 253 described above are sent out, and each of these units ends the charging operation and the rehydration operation in response to the input of the determination result indicating that the capacity of the test battery 252 is exhausted. Has become.
In FIG. 8, the electricity quantity calculation unit 254 corresponds to the oxidation electricity quantity calculation means 134, and the charge electricity quantity calculation unit 2
71 obtains the total amount of charge Qt charged in the test battery 252 based on the charging current Is and the charging time Ts,
It is configured to be sent to the subtraction processing unit 272.

Further, the electrolysis amount calculation unit 273 is configured to calculate the electrolysis amount Qd consumed for electrolysis of water based on the above-mentioned water supply amount Wr. The electrolytic electricity amount calculation unit 273 is the same as the replenishment amount holding unit 26 described above.
From 3, the value of the replenished water content in grams is received as the water replenishment amount Wr, and the electrolytic electricity amount Qd is obtained by multiplying the electricity amount Ed required for electrolyzing 1 gram of water. , To the subtraction processing unit 272.

Further, in FIG. 8, the discharge electricity quantity calculation unit 2
74 receives the number of times n the capacity check is performed, the discharge current Ic, and the discharge time Tc from the capacity check unit 255 , and calculates the check electricity amount Qc consumed for the capacity check based on these values. , To the subtraction processing unit 272.

The amount of electricity for oxidation Qp thus obtained is
It is the amount of electricity charged in the test battery 252 before the deterioration of the positive electrode progresses to such an extent that the required minimum capacity cannot be supplied. Therefore, the positive electrode life evaluation means 135
The life prediction unit 256 corresponding to calculates the required time until the above-mentioned deteriorated electricity amount Qp is supplied by the charging current supplied at the time of trickle charging, and sets this period as the positive electrode life Lp based on the deterioration of the positive electrode. You can output it.

In this case, by comparing the positive electrode life Lp obtained as described above with the specified life Ls of the battery, the positive electrode itself of the test battery 252 is required to satisfy the specified life Ls of the battery. It is possible to directly evaluate whether or not the performance is satisfied. Therefore, this evaluation result can be provided to the determination of the material of the positive electrode and the design of its structure to support the design work, and the efficiency of the design work can be improved. Further, as described above, in the environment described in claim 7, by continuously charging the test battery 252, the test battery 2
It is possible to accelerate the deterioration of the positive electrode of No. 52 to the maximum, and to cause the deterioration of the positive electrode corresponding to three years in a normal state in a short period of about one month, for example. As a result, the battery evaluation period can be significantly shortened.

Therefore, in addition to the above-mentioned life evaluation focusing on the decrease of the electrolytic solution, based on sufficient life evaluation,
It is possible to decide to adopt a battery and install it in an information processing system. This makes it possible to reliably replace the battery included in the information processing system within the valid period, which can contribute to the improvement of the reliability of the information processing system.

Further, as shown in FIG.
If the test battery 252 and the rehydration working unit 253 are arranged in the high-humidity environment chamber 257 by applying the invention of No. 1, the moisture permeating from the case of the test battery 252 is suppressed,
The factor of reduction of the electrolytic solution can be limited to only electrolysis at the positive electrode. In this way, by eliminating the permeation of water from the case, the electrolytic electricity quantity calculating unit 273 can accurately determine the electricity quantity consumed purely for the electrolysis in the positive electrode, and the deteriorated electricity quantity. It is possible to improve the calculation accuracy of Qp.

[0047]

As described above, the inventions of claim 1, claim 3, and claim 2 and claim 6 reduce the electrolyte and deteriorate the positive electrode, which are the direct factors that cause the capacity reduction of the battery. By directly focusing on each of these factors and directly evaluating the progress of these factors, the battery life due to each factor can be evaluated independently. As a result, it becomes possible to support the battery design work and manufacturing work by providing evaluation results for each factor, and improve the efficiency of new product development work.
Further, by applying claim 4 and claim 7 to the inventions of claim 3 and claim 6, respectively, effective acceleration can be applied according to the nature of each factor, so that it is possible to evaluate the life of the battery. The required period can be significantly shortened, and it becomes possible to perform a sufficient life evaluation when a new product is adopted, which can contribute to the improvement of the reliability of an information processing system equipped with a battery.

Furthermore, by applying the invention of claim 5 to the invention of claim 3, it is possible to predict the service life in an environment severer than the normal use environment and improve the safety. In addition, by applying the invention of claim 8 to the invention of claim 6, the permeation of water is excluded from the factor of decreasing the electrolytic solution, and the amount of electricity consumed for electrolysis of water during charging of the battery is reduced. It can be accurately obtained and used for calculation of the amount of deteriorated electricity.

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of the invention of claim 1;

FIG. 2 is a diagram showing the principle of the invention of claim 2;

FIG. 3 is a principle block diagram of the battery life evaluation device according to any one of claims 3 to 5.

FIG. 4 is a principle block diagram of a battery life evaluation device according to claims 6 to 8;

FIG. 5 is a configuration diagram of an embodiment of a battery life evaluation device according to claims 3 to 5;

FIG. 6 is a diagram illustrating a change over time in the amount of electrolytic solution.

FIG. 7 is a diagram showing a correspondence relationship between an electrolytic solution amount and a capacity.

FIG. 8 is a configuration diagram of an embodiment of a battery life evaluation device according to claims 6 and 7;

FIG. 9 is a configuration diagram of an embodiment of a battery life evaluation device to which the invention of claim 8 is applied.

[Explanation of symbols]

101, 102 battery 111 Correlation evaluation means 112 Limiting Liquid Volume Calculation Means 113 Weight measuring means 114 Electrolyte Solution Prediction Means 115 Life Prediction Means 121, 222, 233 sample batteries 122 First Charging Means 123 Capacity measuring means 124 Liquid amount measuring means 125 Correlation extraction means 126 Permeation moisture measuring means 127 Permeation gas measuring means 131 Second charging means 132 Hydration means 133 Capacity inspection means 134 Oxidation electricity amount calculation means 135 Positive electrode life evaluation means 136 environment setting means 211 Electrolyte quantity measurement unit 212 Extrapolation Processing Unit 213 Capacity measuring unit 214 Correlation extractor 215, 256 Life prediction unit 221, 261 Weight measuring unit 222 Low humidity environment room 224, 235, 251 Charging circuit 225 Measured value storage 226 Change rate calculator 227 Electrolyte quantity prediction unit 231 constant current circuit 232, 265 Voltage measurement unit 234 Capacity calculator 236 Charge control circuit 241 Critical Liquid Volume Calculator 242 Life calculation section 252 Test battery 253 Water replenishment work section 254 Electricity calculation section 255 capacity check section 257 high humidity environment room 262 Hydration Unit 263 Replenishment amount holding unit 264 discharge circuit 266 Capacity determination unit 271 Charged electricity amount calculation unit 272 Subtraction processing unit 273 Electrolytic electricity amount calculation unit 274 Discharged electricity quantity calculator

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01M 10/42-10/48 G01R 31/36

Claims (8)

(57) [Claims] 1. A battery life evaluation method for evaluating the life of a battery in which an electrolyte is enclosed in a case, wherein the relationship between the amount of electrolyte and the amount of electricity the battery can supply, that is, the capacity of the battery is evaluated in advance. In advance, the weight change of the battery is measured over a predetermined period, and based on the measurement result, the change in the remaining amount of the electrolytic solution of the battery after the predetermined period is predicted, and the prediction result and the electrolytic Based on the evaluation result of the relationship between the amount of liquid and the capacity of the battery, the time required for the amount of electrolytic solution to decrease until the battery cannot hold the minimum required capacity is calculated, A battery life evaluation method, characterized in that the result of life evaluation is used. 2. A battery life evaluation method for evaluating the life of a battery having a structure in which a paste containing an electrolytic solution is held and a current is collected by a metal grid forming both electrodes, wherein a constant current is supplied to the battery life evaluation method. The battery is constantly charged, and it is determined at a predetermined time interval whether or not the battery holds a predetermined capacity.If the battery holds a predetermined capacity, the battery is continuously charged. , If the battery does not hold a certain capacity,
After the charging of the battery is completed, the amount of electricity consumed for electrolysis of water and the inspection of the capacity in the battery during charging is evaluated, and the sum of the evaluation result and the amount of charged electricity supplied to the battery. The amount of oxidative electricity consumed to oxidize the positive electrode of the battery is calculated based on the above, and the positive electrode of the battery is determined based on the amount of oxidative electricity and the trickle charging current value supplied in the use state of the battery. There for oxidative degradation reactions, seeking time required until impossible holding said predetermined capacity, battery life evaluation method which is characterized in that the evaluation results of the life due to the positive electrode deterioration. 3. A battery life evaluation device for evaluating the life of a battery having a structure in which an electrolytic solution is enclosed in a case, and a correlation evaluation means for evaluating a correlation between the amount of the electrolytic solution and the capacity of the battery, and the electrolytic solution. Limiting liquid amount calculating means for obtaining a limiting amount of electrolytic solution that makes it impossible for the battery to supply the required minimum amount of capacity based on the correlation between the amount and the capacity, and the weight of the battery over a predetermined period. Weight measurement means for measuring the change, based on the measurement result by the weight measurement means, an electrolyte solution amount prediction means for predicting a change in the electrolyte solution amount after the predetermined period, and a prediction result by the electrolyte solution amount prediction means Life estimation means for predicting a period required until the amount of electrolyte in the battery reaches the limit amount based on Apparatus. 4. The battery life evaluation apparatus according to claim 3, wherein the correlation evaluation means individually supplies a charging current to each of the sample batteries for different periods with the case of the plurality of sample batteries opened. Charging means, capacity measuring means for measuring the capacity of each of the plurality of sample batteries, liquid amount measuring means for measuring the amount of electrolyte solution of each of the plurality of sample batteries, capacity of the plurality of sample batteries and amount of electrolyte solution And a correlation extraction means for extracting a correlation based on the above. 5. The battery life evaluation apparatus according to claim 3, wherein the weight measuring means places the battery in a low humidity environment, and measures the weight change due to the permeation of water from the case. A battery life evaluation device comprising: a permeated gas measuring unit that supplies a predetermined charging current to the battery and measures a change in weight due to a gas generated by electrolysis of water permeating through the case. . 6. A battery life evaluation device for evaluating the life of a battery configured to hold a paste containing an electrolytic solution and collect an electric current by means of metal grids constituting both electrodes. continuous supply the charging current
A continuous charging means, a water replenishing means for replenishing water in accordance with the amount of the electrolyte remaining in the battery, and a capacity checking means for inspecting whether the battery maintains a predetermined capacity at a predetermined time interval, Based on the inspection result by the capacity inspecting unit, the charging electricity amount supplied by the charging unit, and the moisture amount supplied by the water replenishing unit, the electricity amount for oxidation consumed in the oxidation reaction of the positive electrode of the battery is calculated. The period of time required until the amount of oxidized electricity is supplied to the positive electrode of the battery is calculated as the life of the positive electrode based on the amount of oxidized electric power calculation means and the charging current value supplied to the battery in the actual use state. And a positive electrode life evaluation means for controlling the life of the battery. 7. The battery life evaluation apparatus according to claim 6, wherein the battery is in a state in which the case holding the paste containing the metal grids of both electrodes and the electrolytic solution is open. Life evaluation equipment. 8. The battery life evaluation apparatus according to claim 6, further comprising environment setting means for setting an environment of high humidity to a degree that suppresses a phenomenon of water permeation from a case of the battery. Battery life evaluation device.