JP3129150B2 - Battery life prediction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for predicting the life of a lead-acid battery, particularly a lead-acid battery used for trickle or float charging, which indicates the remaining life of the lead-acid battery.

[0002]

2. Description of the Related Art Conventionally, there are two methods for detecting the life and the degree of deterioration of a lead storage battery: (1) a method of detecting the variation of each cell voltage of the lead storage battery (described in JP-A-2-304876); (3) a method of detecting by an increase in differential internal resistance (described in JP-A-63-168882), and (4) a method of detecting by the degree of expansion of a positive electrode plate of a lead storage battery ( JP 62
No. 47975), (5) a method of detecting a lead storage battery by periodically performing a discharge test, and (6) a method of integrating a charged amount of electricity and estimating a life based on the charged amount of electricity (Japanese Unexamined Patent Publication No. (2) A method of measuring the relationship between the storage battery temperature and the charging current in advance and integrating the value obtained by converting the storage battery temperature into the charging current to estimate the life (Japanese Patent Publication No. 6-105627). There is.

[0003] Based on the measurement results obtained by these methods, the deterioration state of the storage battery is comprehensively diagnosed. If the charge voltage of the storage battery is managed in the normal range,
Unless defective products are included, it is most affected by the ambient temperature of the storage battery. Normally, the life of a lead storage battery becomes longer as the installation environment temperature becomes lower up to a certain temperature, and the capacity deterioration is less. Conversely, the higher the installation environment temperature, the shorter the life.

For example, the life of a lead storage battery used in trickle charge or float charge at an installation environment temperature of 40 ° C. is only 15 degrees from 25 ° C., which is usually regarded as normal temperature, but the life at 25 ° C. On the other hand, it becomes about 1/3. Thus, the installation environment temperature is one of the major factors affecting the life of the lead storage battery. The installation environment of the lead-acid battery may be installed at a constant temperature of around 23 ° C with air conditioning if it is in the same frame as the rectifier, etc. In most cases, it is installed in an environment where the temperature changes in the four seasons, day and night as well as the external environment temperature.

[0005] Nevertheless, the life of the storage battery is estimated assuming a constant temperature environment of usually 20 to 25 ° C in terms of the deterioration rate due to the age of the storage battery. For this reason, the difference between the estimated life and the actual life becomes large, and the discharge duration required as an alternative power supply during an actual commercial power outage cannot be maintained. When the discharge performance was examined, the performance was still sufficiently maintained, and there were problems such as waste of resources.

In the above-mentioned conventional methods (1) to (5), since it is not possible to estimate how many years until the life of the storage battery is reached only by judging whether or not the life of the storage battery, it is necessary to test the renewal plan of the storage battery equipment. There was a problem that the result could not be reflected.

In order to solve the above-mentioned problems, the present inventors previously measured the surface temperature of the storage battery continuously using a microprocessor having a means for measuring the surface temperature of the storage battery, and found that the surface temperature was lower than the reference temperature. At the time, the average temperature is calculated as a reference temperature, and the storage battery deterioration date is detected by referring to the storage battery installation date preset in the memory and the standard life years corresponding to the average temperature, and detecting how many years are remaining until the life of the storage battery. An apparatus was proposed (Japanese Patent Application No. 6-102669).

[0008]

In the above-described storage battery deterioration diagnosis apparatus proposed by the present inventors, the capacity and type of the storage battery,
The specifications such as the composition of the electrode plate inside the battery, the filling density of the active material, the concentration of the sulfuric acid as the electrolytic solution, and the like are slightly different depending on the manufacturer, so that the life of the same sealed type lead-acid battery is different. For this reason, when the standard life data at the average temperature of the storage battery is treated as being constant, there is a problem that the actual life is far from the calculated estimated life.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a battery life predicting device capable of displaying and outputting a remaining actual life in accordance with the life of the storage battery in accordance with the specification and operating temperature environment. I do.

[0010]

According to the present invention, a device for predicting the life of a storage battery according to the present invention measures the surface of the storage battery at regular intervals by means for measuring the installation environment temperature of the storage battery and a microprocessor having a calendar function. When the surface temperature is equal to or lower than the reference temperature, the average temperature is calculated as the reference temperature, and the standard life years corresponding to the average temperature previously set in the memory are referred to. Furthermore, a life coefficient corresponding to the life characteristic of the storage battery is calculated by multiplying the standard life by a correction coefficient corresponding to the life characteristic of the storage battery obtained by a life test or the like. By subtracting the elapsed years after installation calculated from the installation date of the storage battery set in the memory and the current date obtained from the calendar function of the microprocessor from the above-mentioned life years, the number of years until the life of the storage battery is obtained. It can be displayed more accurately.

[0011]

According to the present invention, it has been found that the life characteristics of a lead storage battery used for trickle and float charging with respect to the environmental temperature show almost the same tendency even if the specifications of the lead storage battery are different. It is possible to obtain an accurate number of years of life corresponding to the remaining life.

[0012]

Embodiments of the present invention will be described below.

MSE2 with a nominal voltage of 2 V and a rated capacity of 200 Ah from three different manufacturers A, B and C
The life characteristics due to trickle charging were examined using sealed lead storage batteries A, B, and C corresponding to the 00 type. 40 ℃
FIG. 1 shows the results of trickle charging at a charging voltage of 2.25 V under the environment described above, and checking the battery capacity by discharging 0.25 CA every 10 months.

FIG. 2 shows the results of a life characteristic test similarly performed in an environment of 35 ° C. As is clear from FIGS. 1 and 2, the life characteristics of the lead storage battery at the environmental temperatures of 40 ° C. and 35 ° C. all show the same tendency. Is declining. Further, assuming that the life is when the capacity retention rate reaches 80%, the lead storage battery A at an installation environment temperature of 40 ° C.
The ratios of the lifetimes of B and C to the lifetime of No. were 0.67 and 0.48, respectively. Also, if the installation environment temperature is 3
Even at 5 ° C., the ratio of the life years of B and C to the lead storage battery A is the same as that at 40 ° C.

Although the absolute value of the number of years until the end of the life varies depending on the specifications and the like of the lead storage battery used in this way, the degree of change in the life characteristic with respect to the installation environment temperature, in other words, the reference storage battery, The ratio of the service life of the storage battery to the service life is almost the same without being affected by the installation environment temperature. From the above test results, it is possible to obtain a correction coefficient for the life characteristics of B and C for the lead storage battery A.

That is, the characteristics of the lead-acid battery A are defined as the standard life. In the case of A, the correction coefficient (f) is set to 1.00. In the case of B, f = 0.67 from the above test result. In this case, f = 0.48.

On the other hand, Table 1 shows the estimated standard life years (YL) of the lead storage battery A in units of 1 ° C. in an environmental temperature range of 20 ° C. to 40 ° C. These values are stored in the RAM. Set it.

[0018]

[Table 1]

FIG. 3 is a block diagram showing a life predictor according to an embodiment of the present invention. In FIG. 3, reference numeral 7 denotes a microprocessor which is a control / calculation unit, 8 denotes a program memory (ROM), 9 denotes a standard life data (YL) at a storage battery installation date and each average temperature in Table 1 and a correction coefficient ( f) A data memory (RAM) for storing data such as an average temperature calculated based on the storage battery surface temperature measured at regular time intervals.

Reference numeral 10 denotes a calendar IC which is used to calculate the number of years elapsed after the storage battery is installed from the installation date of the storage battery stored in the data memory 9 and to display the current date and time on the display device 13. Reference numeral 11 denotes an input / output interface to which an operation switch 12, a display device 13 such as a liquid crystal, and an A / D converter 14 for taking analog data such as temperature data 15 of a storage battery into the microprocessor 7 are connected.

Next, an example of the process of calculating the remaining life years in the life prediction device according to the present invention will be described with reference to the flowchart shown in FIG.

1. First, the temperature data of the battery surface (15)
Is measured once an hour (16, 17). At this time, if the measured temperature is lower than the reference temperature (19), the reference temperature is set as the reference temperature (for example, the surface temperature measured at the reference temperature of 20 ° C is 15 ° C).
In the case of (2), the measurement temperature (MSETMP) is set to 20 ° C. (20)) The process of calculating the average temperature (t) is repeated (18, 21, 22).

2. Next, the standard life years (YL) corresponding to the average temperature (t) (Table 1) are obtained from the data memory (23), and the life years (YLr) are multiplied by the correction coefficient (f) of the storage battery corresponding to YL. Ask (24).

3. The age (YPST) after the storage battery is installed is obtained from the storage battery installation date and the calendar IC (10) in the data memory (9) (25), and the elapsed life (YPST) is subtracted from the life years (YLr) to obtain the remaining life (LIFE).
RMD) (26).

4. The date and time are always displayed on the display device (13), and when there is a display instruction of the remaining life years by the operation switch (12), these calculated values are displayed (27).

Next, using the life prediction device of the present invention,
Sealed lead-acid batteries A, B with a nominal voltage of 2 V and a capacity of 200 Ah,
C at a temperature of 40 ° C
The trickle charge was performed at a voltage of 2.25 V per cell while repeatedly changing the room temperature and the normal temperature at 12-hour intervals, and discharge was performed every 6 months at a constant current of 0.1 CA until the voltage reached 1.8 V / cell. The charging and discharging were repeated until the life reached when the life reached 80% of the initial discharge capacity. Table 2 shows the relationship between the number of years elapsed, the capacity retention rate, and the number of years of life estimated according to the present invention.

[0027]

[Table 2]

In the method proposed above, the trickle life characteristics of the lead storage batteries of the manufacturers of B and C are different from those of the company A, so that there is a large difference between the estimated life and the actual life. As is evident from the results, it was demonstrated that the estimated life and the actual life became closer by multiplying by the correction coefficient according to the present invention.

[0029]

As described above, the life prediction device according to the present invention can accurately grasp the remaining life of the relevant lead-acid battery only by setting the correction coefficient, even if lead-acid batteries having different life characteristics are used. Can be displayed, and a renewal plan of the storage battery equipment can be efficiently made.

[Brief description of the drawings]

FIG. 1 is an installation environment temperature 4 of a sealed lead-acid battery used for obtaining a standard life and a correction coefficient according to an embodiment of the present invention.
Diagram showing trickle charge life characteristics at 0 ° C.

FIG. 2 shows the installation environment temperature 3 of the sealed lead-acid battery used for obtaining the standard life years and the correction coefficient of the embodiment of the present invention.
Diagram showing trickle charge life characteristics at 5 ° C.

FIG. 3 is a block diagram of a life predictor according to an embodiment of the present invention.

FIG. 4 is a flowchart illustrating a process of calculating a remaining life according to the embodiment of the present invention.

[Explanation of symbols]

 7 Microprocessor 8 Program memory 9 Data memory 15 Measurement data of surface temperature of lead-acid battery

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01M 10/42-10/48 G01R 31/36 H02J 7/00-7/36

Claims (1)

(57) [Claims] 1. A surface temperature of a lead storage battery is automatically measured at regular time intervals by means of means for intermittently measuring the installation environment temperature of the lead storage battery and a microprocessor having a calendar function, and the average temperature (t) (however, , T is the average temperature of the lead-acid battery surface continuously measured and calculated as the reference temperature when the surface temperature of the lead-acid battery is equal to or lower than the reference temperature, and corresponds to the average temperature of the installation environment. The standard life years and the continuously calculated average temperature (t) are compared and collated to obtain a corresponding standard life years (YL), and any correction corresponding to a lead-acid battery set in advance to the standard life years is obtained. The value (YL × f) multiplied by the coefficient (f) is defined as the life of the lead-acid battery, and the date of installation of the lead-acid battery stored in the memory and the number of years elapsed since the lead-acid battery was installed (Y) obtained from the calendar function. Kotobuki The value was subtracted from the number of years (YL × f
-Y) is a device for notifying the life of the storage battery, which displays the remaining life years.