Method for determining abnormality of electrical connection terminal of charge / discharge inspection device

Abstract

To provide a method for assessing the abnormality of electric connection terminals of a charge / discharge inspection device with which it is possible to detect the abnormality such as aging degradation or poor contact of each of the electric connection terminals of a charge / discharge power supply in a charge / discharge inspection device, reliably and efficiently replace only an electric connection terminal where abnormality exists, thus making it possible to significantly cut back the cost and labor required for maintenance.SOLUTION: The measured data of output voltage of a charge / discharge power supply 12 acquired during charge / discharge inspection of a plurality of secondary batteries 10 and battery voltage between positive and negative electrodes 18a, 18b of each secondary battery 10 are accumulated in time series, and the presence of degradation tendency of positive / negative electric connection terminals 13a, 13b of each set of charge / discharge power supply 12 and poor contact between positive / negative electric connection terminals 13a, 13b of each set of charge / discharge power supply 12 and positive / negative electrodes 18a, 18b of each secondary battery 10 are diagnosed on the basis of each measured data.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for determining abnormalities in electrical connection terminals of a charge / discharge inspection device, which can detect abnormalities such as deterioration and poor contact of electrical connection terminals in a charge / discharge inspection device with high accuracy during charge / discharge inspection (test) of a secondary battery. [Background technology]

[0002] Conventionally, charge / discharge testing of secondary batteries is performed by electrically connecting the electrical connection terminals (e.g., probe pins, clips, or round terminals) of a charge / discharge power supply of a charge / discharge testing device to the electrodes of the secondary battery. Therefore, to perform accurate charge / discharge testing, it is necessary to check for abnormalities, such as wiring (path) anomalies from the charge / discharge power supply to the secondary battery and poor connections (contacts) between the electrical connection terminals and the electrodes of the secondary battery. If abnormalities are detected, it is necessary to replace parts or perform other maintenance. For example, Patent Document 1 proposes a charge / discharge testing system that calculates the resistance of a charging path and compares the calculated resistance with the designed resistance of the charging path to determine whether there is an abnormality in the charging path. Patent Document 2 also proposes a charge / discharge testing device that calculates the contact resistance between a load line through which a charging / discharging current flows and the positive and negative terminals (electrodes) of a secondary battery, and detects poor contact between the load line (electrical connection terminals) and the positive and negative terminals based on the magnitude of the calculated resistance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6086768 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-117995 Summary of the Invention [Problem to be solved by the invention]

[0004] In this way, when calculating the absolute value of resistance to determine an abnormality, a reference value for the determination is required. That is, in Patent Documents 1 and 2, in addition to the designed (normal) resistance (path resistance, line resistance) of the charging path (from the charging / discharging power source to the secondary battery) and the contact resistance when the load line (electrical connection terminal) and the positive and negative terminals of the secondary battery are in normal contact, a threshold value (allowable limit value of the amount of resistance fluctuation) is required to determine whether or not an abnormality exists. However, in order for the charge / discharge inspection device to perform charge / discharge inspections of a large number of secondary batteries simultaneously (in parallel), multiple secondary batteries are connected to each of one or more charge / discharge power sources, and the distance (length of the wiring (path)) from each output terminal of each charge / discharge power source to the electrode of each secondary battery differs depending on the channel, and the wiring resistance (line resistance) also differs depending on the channel. Therefore, in order to perform strict abnormality judgment based on the absolute value of resistance, it is necessary to set an abnormality judgment value (threshold value) corresponding to the normal wiring resistance value (line resistance value) for each channel, which poses the problem of time-consuming setting. Furthermore, Patent Document 1 proposes a method for determining whether or not there is an abnormality in the charging path by comparing a calculated resistance value with a design resistance value, as well as a method for determining whether or not there is an abnormality in the charging path by comparing a currently calculated resistance value with a previously calculated resistance value and determining whether or not there is an abnormality if the difference is greater than a predetermined threshold, and a method for determining whether or not there is an abnormality in the charging path by comparing a currently calculated resistance value with an average value of previously calculated resistance values ​​within a predetermined period of time and determining whether or not there is an abnormality if the difference is greater than a predetermined threshold. These methods do not require the design resistance value to be calculated, but in order to determine whether or not there is an abnormality by comparing a currently calculated resistance value with a previously calculated resistance value or an average value of previously calculated resistance values ​​within a predetermined period of time, it is necessary to set a threshold value, as with the above-mentioned method. Furthermore, Patent Document 1 is specialized in detecting abnormalities in the charging path, focusing on defects in elements such as reactors and fuses arranged in the charging path, and poor contact such as loose bolts that electrically connect these elements, but the probability of such wiring path defects (deterioration) occurring is extremely low. Meanwhile, in actual charge / discharge inspections, the electrical connection terminals of charging / discharging power supplies, which are repeatedly electrically connected to the electrodes of secondary batteries that are transported one after another by abutting (butting), fitting, clamping, or other methods, are prone to deterioration over time such as wear and tear and the resulting poor contact, and although electrical connection terminals are frequently replaced, detection of deterioration of electrical connection terminals has not been considered. Furthermore, Patent Document 2 is specialized in detecting poor contact between a load line (electrical connection terminal) and an electrode of a secondary battery, and detects poor contact between the load line and an electrode by directly calculating the contact resistance between the load line through which charging / discharging current flows and the electrode of the secondary battery, and therefore cannot detect deterioration over time due to abnormalities or wear of the electrical connection terminal itself. For the reasons described above, until now it has not been possible to individually detect the deterioration state of each electrical connection terminal of a charging / discharging power supply, and therefore all electrical connection terminals have been replaced periodically without checking whether or not there is actual deterioration, which has resulted in increased maintenance costs and effort, making it uneconomical and inefficient in terms of resource conservation.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a method for determining abnormalities in the electrical connection terminals of a charge / discharge inspection device, which can detect abnormalities such as deterioration over time and poor contact in each electrical connection terminal of a charge / discharge power supply in a charge / discharge inspection device with high accuracy, and enables only the electrical connection terminals in which an abnormality has occurred to be replaced reliably and efficiently, thereby significantly reducing the cost and effort required for maintenance. [Means for solving the problem]

[0006] In accordance with the above-mentioned object, the method for determining an abnormality in electrical connection terminals of a charge / discharge inspection device according to the present invention is a method for determining an abnormality in electrical connection terminals of a charge / discharge inspection device, which individually detects abnormalities in each of multiple pairs of positive and negative electrical connection terminals in one or multiple charge / discharge power sources of a charge / discharge inspection device for simultaneously testing the charge / discharge of multiple secondary batteries, and Measurement data of the output voltage of each charging / discharging power supply and the battery voltage between the positive and negative electrodes of each secondary battery obtained during charging / discharging inspection of the multiple secondary batteries is accumulated in chronological order, and based on the measurement data, a diagnosis is made of the deterioration tendency of the positive and negative electrical connection terminals of each pair of each charging / discharging power supply and the presence or absence of poor contact between the positive and negative electrical connection terminals of each pair of each charging / discharging power supply and the positive and negative electrodes of each secondary battery.

[0007] In the method for determining abnormalities in the electrical connection terminals of a charge / discharge inspection device according to the present invention, the presence or absence of a tendency for deterioration of the positive and negative electrical connection terminals of each pair of each charge / discharge power source can be diagnosed from the change over time in the voltage difference between the output voltage of each charge / discharge power source and the battery voltage of each secondary battery electrically connected to the positive and negative electrical connection terminals of each pair of each charge / discharge power source.

[0008] In the method for determining abnormalities in the electrical connection terminals of the charge / discharge inspection device according to the present invention, it is preferable to diagnose, among the positive and negative electrical connection terminals of each pair of the charge / discharge power sources, the positive and negative electrical connection terminals whose voltage difference shows an increasing tendency over time as being prone to deterioration.

[0009] In the method for determining an abnormality in the electrical connection terminals of a charge / discharge inspection device according to the present invention, it is further preferable that the change in the voltage difference over time is determined using as an initial value the voltage difference between the output voltage of each of the charge / discharge power sources and the battery voltage of each of the secondary batteries electrically connected to the positive and negative electrical connection terminals of each of the charge / discharge power sources, which is obtained immediately after the positive and negative electrical connection terminals of each of the pairs of the charge / discharge power sources are replaced with new ones.

[0010] In the method for determining an abnormality in an electrical connection terminal of a charge / discharge inspection device according to the present invention, it is preferable that the accumulation of the measurement data is carried out while the charge / discharge power sources are outputting the same set current.

[0011] In the method for determining an abnormality in an electrical connection terminal of a charge / discharge inspection device according to the present invention, measurement data on the output current of each of the charge / discharge power sources can be accumulated in chronological order during the charge / discharge inspection of the secondary battery.

[0012] In the method for determining an abnormality in the electrical connection terminals of a charge / discharge inspection device according to the present invention, measurement data on the battery temperature of each secondary battery may be accumulated during a charge / discharge inspection of the secondary battery, and the presence or absence of poor contact between the positive and negative electrical connection terminals of each set of each charge / discharge power source and the positive and negative electrodes of each secondary battery may be diagnosed based on the battery temperatures. [Effects of the Invention]

[0013] The method for determining abnormalities in electrical connection terminals of a charge / discharge inspection device according to the present invention accumulates measurement data in chronological order of the output voltage of each charge / discharge power supply and the battery voltage between the positive and negative electrodes of each secondary battery obtained during charge / discharge inspection of a plurality of secondary batteries, and can diagnose the deterioration tendency of each set of positive and negative electrical connection terminals of each charge / discharge power supply and the presence or absence of poor contact between each set of positive and negative electrical connection terminals of each charge / discharge power supply and the positive and negative electrodes of each secondary battery based on the accumulated measurement data. This means that no dedicated diagnostic tool or the like is required, and no influence from the wiring resistance of each channel can be exerted, and replacement or maintenance of only the electrical connection terminals that are tending to deteriorate or have poor contact can be efficiently performed. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is an explanatory diagram of a method for determining an abnormality in an electrical connection terminal of a charge / discharge inspection device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] Next, embodiments of the present invention will be described with reference to the accompanying drawings to facilitate understanding of the present invention. The method for determining an abnormality in electrical connection terminals of a charge / discharge inspection device according to one embodiment of the present invention shown in Figure 1 detects with high accuracy the presence or absence of abnormalities, such as deterioration and poor contact, in multiple pairs of positive and negative electrical connection terminals 13a, 13b in a charge / discharge power supply 12 of a charge / discharge inspection device 11 for simultaneously inspecting (testing) multiple secondary batteries 10. Here, the number of secondary batteries 10 that can be connected to one charge / discharge power supply 12 can be selected as appropriate. Note that while Figure 1 shows a case in which the charge / discharge inspection device 11 is equipped with one charge / discharge power supply 12, the charge / discharge inspection device can be equipped with multiple charge / discharge power supplies, the number of which can be selected as appropriate.

[0016] 1, a management computer 15 is connected to a charge / discharge inspection device 11 via a controller (digital data collector) 14. The charge / discharge inspection device 11 also has an output voltage meter 17 that measures the output voltage of the charge / discharge power supply 12 for each secondary battery 10, a battery voltage meter 19 that measures the battery voltage between the positive and negative electrodes 18a, 18b of each secondary battery 10, an output current meter 20 that measures the output current of the charge / discharge power supply 12 for each secondary battery 10, and a temperature sensor 21 that measures the battery temperature of each secondary battery 10. This allows the management computer 15 to accumulate measurement data in chronological order, which data are acquired during the charge / discharge inspection of multiple secondary batteries 10, including the output voltage of the charge / discharge power supply 12, the battery voltage between the positive and negative electrodes 18a, 18b of each secondary battery 10, the output current of the charge / discharge power supply 12, and the battery temperature of each secondary battery 10. Based on these measurement data, the management computer 15 can diagnose the deterioration tendency of each pair of positive and negative electrical connection terminals 13a, 13b of the charging / discharging power supply 12 and the presence or absence of poor contact between each pair of positive and negative electrical connection terminals 13a, 13b of the charging / discharging power supply 12 and the positive and negative electrodes 18a, 18b of each secondary battery 10.

[0017] Specifically, for example, the presence or absence of abnormalities (deterioration tendency and poor contact) in the positive and negative electrical connection terminals 13a, 13b of each set of the charging and discharging power supply 12 can be diagnosed from the change over time (amount of increase) in the voltage difference between the output voltage of the charging and discharging power supply 12 for each secondary battery 10 and the battery voltage of each secondary battery 10 electrically connected to each set of the positive and negative electrical connection terminals 13a, 13b of the charging and discharging power supply 12. More specifically, of the positive and negative electrical connection terminals 13a, 13b of each set of the charging and discharging power supply 12, the positive and negative electrical connection terminals 13a, 13b for which the voltage difference is increasing over time can be diagnosed as being deteriorated, and the electrical connection terminals 13a, 13b for which the voltage difference is suddenly (suddenly) fluctuating can be diagnosed as having poor contact with the electrodes 18a, 18b or other malfunctions (failures). The accumulation of each measurement data is performed while the charge / discharge power supply 12 is outputting a set current (a preset identical (constant) current), thereby enabling accurate diagnosis of the presence or absence of abnormalities (deterioration tendency and poor contact) in each of the electrical connection terminals 13a, 13b. In particular, when the charge / discharge inspection device is equipped with multiple charge / discharge power supplies, the accumulation of each measurement data is performed while each charge / discharge power supply is outputting the same set current, thereby enabling accurate diagnosis of the presence or absence of abnormalities in all of the electrical connection terminals under the same conditions.

[0018] Furthermore, by simultaneously accumulating measurement data of the output current of each secondary battery 10 of the charging / discharging power supply 12 in chronological order during charge / discharge testing of multiple secondary batteries 10, it is possible to confirm the output current of each secondary battery 10 of the charging / discharging power supply 12 at the time when the measurement data of the output voltage of the charging / discharging power supply 12 for each secondary battery 10 and the battery voltage of each secondary battery 10 was measured, and to verify whether the measurements were performed under a set current output. Furthermore, even if the measurement data of the output voltage of the charging / discharging power supply 12 for each secondary battery 10 and the battery voltage of each secondary battery 10 were not measured under a constant set current output, it is possible to accurately determine whether there is an abnormality in the electrical connection terminals 13a, 13b by extracting the measurement data of the output voltage of the charging / discharging power supply 12 for each secondary battery 10 and the battery voltage of each secondary battery 10 when the output current of the charging / discharging power supply 12 for each secondary battery 10 is equal.

[0019] If an abnormality occurs in the electrical connection terminals 13a, 13b, the management computer 15 can notify an operator using a monitor and / or a speaker (neither of which are shown), etc. For example, warning letters or symbols can be displayed on the monitor or a warning sound can be emitted from the speaker to notify the operator of the abnormality and prompt the operator to replace or perform maintenance on the electrical connection terminals 13a, 13b. Then, by setting the voltage difference between the output voltage of the charging / discharging power supply 12 for each secondary battery 10 obtained immediately after each set of positive and negative electrical connection terminals 13a, 13b of the charging / discharging power supply 12 is replaced with new ones and the battery voltage of each secondary battery 10 electrically connected to each set of positive and negative electrical connection terminals 13a, 13b of the charging / discharging power supply 12 as an initial value (normal value or reference value), and determining the change over time of the aforementioned voltage difference, it is possible to accurately detect whether or not there is an abnormality in each set of positive and negative electrical connection terminals 13a, 13b without being affected by the wiring resistance value (line resistance value) from each output terminal of the charging / discharging power supply 12 to the electrodes 18a, 18b of each secondary battery 10, and in particular, it is possible to detect with high accuracy whether or not there is poor contact with the positive and negative electrodes 18a, 18b of each secondary battery 10. In addition to the change in the voltage difference over time, by accumulating (monitoring) measurement data of the battery temperature of each secondary battery 10 measured by each temperature sensor 21, it is possible to detect abnormal heat generation due to poor contact between each pair of positive and negative electrical connection terminals 13a, 13b of the charging / discharging power source 12 and the positive and negative electrodes 18a, 18b of each secondary battery 10, thereby further improving the accuracy of poor contact diagnosis.

[0020] The above describes an embodiment of the present invention, but the present invention is not limited to the configurations described in the above embodiment, and also includes other embodiments and modifications that are possible within the scope of the matters described in the claims. For example, in the above embodiment, instead of diagnosing the presence or absence of an abnormality in the electrical connection terminals from the change over time (amount of increase) in the voltage difference between the output voltage of the charging / discharging power supply and the battery voltage of each secondary battery electrically connected to the positive and negative electrical connection terminals of each set of the charging / discharging power supply, it is possible to diagnose the presence or absence of an abnormality in the electrical connection terminals by obtaining the differential value (rate of increase) of the change over time in the voltage difference.In addition to this, it is possible to combine multiple types of accumulated measurement data, or process the measurement data using various operations (including addition, subtraction, multiplication, division, as well as differentiation and integration), and use the data for abnormality diagnosis. Furthermore, the shape of the electrical connection terminal of the charging / discharging power source is not particularly limited, and any shape that can be electrically connected to the electrode of the secondary battery can be selected as appropriate. Depending on the shape of the electrode of the secondary battery, various shapes such as a probe pin, a clip, or a round terminal can be adopted. In the above embodiment, the control computer and the controller are independent from the charge / discharge inspection device, but the controller can also be incorporated into the control computer or the charge / discharge inspection device. [Explanation of symbols]

[0021] 10: Secondary battery, 11: Charge / discharge inspection device, 12: Charge / discharge power supply, 13a, 13b: Electrical connection terminal, 14: Controller, 15: Management computer, 17: Output voltage measuring device, 18a, 18b: Electrodes, 19: Battery voltage measuring device, 20: Output current measuring device, 21: Temperature sensor

Claims

1. A method for detecting deterioration over time of electrical connection terminals of a charge / discharge inspection device, which individually detects deterioration over time of each of a plurality of pairs of positive and negative electrical connection terminals in one or a plurality of charge / discharge power sources of a charge / discharge inspection device for simultaneously charging / discharging a plurality of secondary batteries, comprising: A method for detecting deterioration over time of electrical connection terminals of a charge / discharge inspection device, comprising: accumulating measurement data of the output voltage of each of the charge / discharge power sources and the battery voltage between the positive and negative electrodes of each of the secondary batteries in chronological order, obtained during charge / discharge inspection of a plurality of the secondary batteries; and diagnosing the deterioration over time of the positive and negative electrical connection terminals of each pair of the charge / discharge power sources based on the measurement data.

2. 2. The method for detecting deterioration over time of the electrical connection terminals of a charge-discharge inspection device according to claim 1, characterized in that the deterioration over time of the positive and negative electrical connection terminals of each pair of the charge-discharge power supplies is diagnosed from the change over time in the voltage difference between the output voltage of each of the charge-discharge power supplies and the battery voltage of each of the secondary batteries electrically connected to the positive and negative electrical connection terminals of each pair of the charge-discharge power supplies.

3. 3. The method for detecting deterioration over time of an electrical connection terminal of a charge / discharge inspection device according to claim 2, characterized in that, of the positive and negative electrical connection terminals of each pair of the charge / discharge power sources, the positive and negative electrical connection terminals whose voltage difference shows an increasing tendency over time are diagnosed as being prone to deterioration.

4. 4. The method for detecting deterioration over time of an electrical connection terminal of a charge-discharge inspection device according to claim 2 or 3, wherein the change in the voltage difference over time is determined using as an initial value a voltage difference between the output voltage of each of the charge-discharge power sources and the battery voltage of each of the secondary batteries electrically connected to the positive and negative electrical connection terminals of each of the charge-discharge power sources, the voltage difference being obtained immediately after the positive and negative electrical connection terminals of each of the charge-discharge power sources are replaced with new ones.

5. The method for detecting deterioration over time of an electrical connection terminal of a charge / discharge inspection device according to any one of claims 1 to 4, characterized in that the accumulation of each of the measurement data is performed under the condition that each of the charge / discharge power sources outputs the same set current.

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