Thermal shock test system and thermal shock test method

Abstract

To provide a thermal shock testing system and a thermal shock testing method with which it is possible to improve the accuracy of test.SOLUTION: A thermal shock testing system 1 comprises: a test piece 10 that includes a pair of external terminals 12, a holding member 14 and a wiring part 18; a cryostat 20 for cooling the test piece 10 to a first set temperature or below; an energization device 40 which is capable of supplying electricity to the pair of external terminals 12; a temperature sensor 30 for detecting the temperature of one of the pair of external terminals 12; and a control unit 50 for controlling the energization device 40. The control unit 50 causes electricity supply by the energization device 40 to start when the detection value of the temperature sensor 30 reaches the first set temperature and causes electricity supply by the energization device 40 to stop when the detection value of the temperature sensor 30 reaches a second set temperature that is higher than the first set temperature.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a thermal shock testing system and a thermal shock testing method. [Background technology]

[0002] For example, Japanese Patent Application Laid-Open No. 2009-42169 discloses a thermal shock testing device in which a sample is placed in a test chamber and subjected to thermal shock by repeating heating and high temperatures to test the characteristics of the sample. In this thermal shock testing device, the second and subsequent heating operations are performed for the same amount of time required for the sample to reach 150°C in the first heating operation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-42169 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the thermal shock test device described in JP 2009-42169 A, the second and subsequent heating operations are performed for the same time period required for the sample to reach 150°C in the first heating operation, and therefore cooling may begin before the sample reaches the set temperature, resulting in a decrease in test accuracy.

[0005] An object of the present disclosure is to provide a thermal shock test system and a thermal shock test method capable of improving the accuracy of the test. [Means for solving the problem]

[0006] A thermal shock testing system according to one aspect of the present disclosure includes a test specimen including a pair of external terminals, a holding member for holding the pair of external terminals, and a wiring section for electrically connecting the pair of external terminals to each other; a low-temperature chamber for housing the test specimen and cooling the test specimen to a temperature equal to or lower than a first set temperature; a current passing device electrically connected to the pair of external terminals and capable of passing current through the test specimen; a temperature sensor for detecting a temperature of at least one of the pair of external terminals; and a control unit for controlling the current passing device, wherein the control unit starts current passing through the current passing device when a detection value of the temperature sensor reaches the first set temperature, and stops current passing through the current passing device when a detection value of the temperature sensor reaches a second set temperature higher than the first set temperature.

[0007] Moreover, a thermal shock testing method according to one aspect of the present disclosure includes a placement step of placing a test specimen including a pair of external terminals, a holding member for holding the pair of external terminals, and a wiring portion electrically connecting the pair of external terminals to each other in a low-temperature chamber in which the test specimen is cooled until a temperature of the test specimen becomes equal to or lower than a first set temperature, and a cycle testing step of alternately repeating the steps of: raising the temperature of the pair of external terminals by passing an electric current through the test specimen when a temperature of at least one of the pair of external terminals in the low-temperature chamber reaches the first set temperature; and stopping the passage of electric current through the test specimen when the temperature of the one external terminal reaches a second set temperature higher than the first set temperature, and cooling the test specimen in the low-temperature chamber until the temperature of the one external terminal reaches the first set temperature. Effect of the Invention

[0008] According to the present disclosure, it is possible to provide a thermal shock testing system and a thermal shock testing method capable of improving the accuracy of the test. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic perspective view of a thermal shock testing system according to one embodiment of the present disclosure. [Diagram 2]4 is a flowchart showing the control contents of a control unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0011] 1 is a perspective view showing a schematic configuration of a thermal shock test system according to an embodiment of the present disclosure. The thermal shock test system 1 is preferably applied to a power storage cell mounted on a vehicle.

[0012] As shown in FIG. 1, the thermal shock testing system 1 includes a test piece 10, a low-temperature chamber 20, a temperature sensor 30, a current applying device 40, and a control unit 50.

[0013] The specimen 10 is a member to be subjected to a thermal shock test. The specimen 10 is not a completed energy storage cell, but is a replica of an energy storage cell. The specimen 10 includes a pair of external terminals 12, a holding member 14, a pair of insulating members 16, and a wiring portion 18.

[0014] The holding member 14 holds the pair of external terminals 12. The holding member 14 is made of metal.

[0015] Each insulating member 16 is sandwiched between the corresponding external terminal 12 and the holding member 14. Specifically, each insulating member 16 is held in a compressed state between the external terminal 12 and the holding member 14. Each insulating member 16 receives heat from each external terminal 12 when the temperature of the external terminal 12 increases. Each insulating member 16 may have a gasket 16a and an insulator 16b.

[0016] The wiring portion 18 electrically connects the pair of external terminals 12 to each other. In this embodiment, the wiring portion 18 connects the portions of the pair of external terminals 12 that are located inside the holding member 14 to each other. However, the wiring portion 18 may also connect the portions of the pair of external terminals 12 that are located outside the holding member 14 to each other. It is preferable that the wiring portion 18 is provided with a resistor. In this way, the temperature rise time of the external terminals 12 is shortened.

[0017] The low-temperature chamber 20 contains the specimen 10. The low-temperature chamber 20 is capable of cooling the specimen 10 to a first set temperature T1 or lower. The low-temperature chamber 20 is configured as a thermostatic chamber that maintains the temperature inside the low-temperature chamber 20 at the first set temperature T1. The first set temperature T1 is set to, for example, -40°C.

[0018] The temperature sensor 30 detects the temperature of the external terminal 12. In this embodiment, a thermocouple is used as the temperature sensor 30. The detection value T of the temperature sensor 30 is sent to the control unit 50.

[0019] The current passing device 40 is electrically connected to the external terminal 12 and is capable of passing a current through the external terminal 12. In Fig. 1, the flow of current supplied by the current passing device 40 is indicated by arrows. The current passing device 40 has a device body 42 that can be switched between current passing and no current passing, and an electrode 44 connected to the external terminal 12. The current supplied by the current passing device 40 is appropriately set depending on the cross-sectional area, length, material, etc. of the external terminal 12.

[0020] The control unit 50 controls the current supply device 40. The control unit 50 starts current supply by the current supply device 40 when the detection value T of the temperature sensor 30 becomes a first set temperature T1, and stops current supply by the current supply device 40 when the detection value T of the temperature sensor 30 becomes a second set temperature T2 higher than the first set temperature T1. The second set temperature T2 is set to, for example, 65°C.

[0021] Next, the control flow of the control unit 50 will be described with reference to FIG.

[0022] First, the control unit 50 stops the current supply (step S1). This causes the specimen 10 to cool in the low-temperature chamber 10. Thereafter, the control unit 50 determines whether the detected value T of the temperature sensor is the first set temperature T1 or not (step S2). As a result, if the detected value T of the temperature sensor is higher than the first set temperature T1, the control unit 50 returns to step S1. Steps S1 and S2 correspond to the process of cooling the specimen 10 until the temperature of the external terminal 12 becomes the first set temperature T1.

[0023] In step S2, when the detected value T of the temperature sensor is the first set temperature T1, the control unit 50 causes the current supply device 40 to start supplying current to the external terminals 12 (step S3). As a result, current is supplied to the pair of external terminals 12, and the temperature of each external terminal 12 rises due to Joule heat. Furthermore, the temperature of the insulating member 16 in contact with the external terminals 12 also rises in the same manner as the external terminals 12.

[0024] Next, the control unit 50 determines whether the detection value T of the temperature sensor has risen to the second set temperature T2 (step S4). As a result, if the detection value T of the temperature sensor is less than the second set temperature T2, the control unit 50 returns to step S3. Steps S3 and S4 correspond to a process of raising the temperature of the external terminal 12 until the temperature of the external terminal 12 becomes the second set temperature T2.

[0025] In step S4, if the detected value T of the temperature sensor is the second set temperature T2, the control unit 50 adds 1 to the number of cycles n (step S5). Then, the control unit 50 determines whether the number of cycles n is a specified number of cycles or not (step S6). As a result, if the number of cycles n is less than the specified number of cycles, the control unit 50 returns to step S1, and if the number of cycles n is the specified number of cycles, the control unit 50 ends the control.

[0026] The following thermal shock testing method is carried out in the above-described thermal shock testing system 1. This thermal shock testing method includes an arrangement step and a cycle testing step.

[0027] In the placement step, the specimen 10 is placed in the low-temperature chamber 20 .

[0028] In the cycle test process, a heating process and a cooling process are alternately repeated. The heating process is a process of heating the pair of external terminals 12 by passing electricity through the pair of external terminals 12 when the temperature (detection value T of the temperature sensor) of at least one of the pair of external terminals 12 in the low-temperature chamber 20 becomes a first set temperature T1. The cooling process is a process of stopping the passage of electricity through the pair of external terminals 12 when the temperature (detection value T of the temperature sensor) of one of the external terminals 12 becomes a second set temperature T2, and cooling the test specimen 10 in the low-temperature chamber 20 until the temperature of the one of the external terminals 12 becomes the first set temperature T1.

[0029] As described above, in the thermal shock testing system 1 of this embodiment, current flow by the current supply device 40 is started when the detection value T of the temperature sensor 30 reaches the first set temperature T1, and current flow by the current supply device 40 is stopped when the detection value T of the temperature sensor 30 reaches the second set temperature T2, thereby improving the accuracy of the thermal shock testing.

[0030] In the above embodiment, the portions of the pair of external terminals 12 located inside the holding member 14 may be connected to each other by the wiring portion 18, and the portions of the pair of external terminals 12 located outside the holding member 14 may be connected to each other by another wiring portion (not shown). In this case, by increasing the value of the current supplied by the current supply device 40, the temperature rise time of the external terminals 12 is shortened.

[0031] In the above embodiment, instead of the second set temperature T2, a third set temperature higher than the second set temperature T2 is adopted, thereby making it possible to reduce the number of cycles (shorten the test time).

[0032] Furthermore, the control unit 50 may stop current application by the current application device 40 when the time required for the temperature sensor detection value T to reach the second set temperature T2 from the first set temperature T1 has elapsed after the current application by the current application device 40 has started, and may start current application by the current application device 40 when the time required for the temperature sensor detection value T to reach the first set temperature T1 from the second set temperature T2 has elapsed after the current application by the current application device 40 has stopped. However, even in this case, the control based on the set temperatures T1 and T2 takes precedence.

[0033] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0034] The thermal shock testing system in the above embodiment includes a test specimen including a pair of external terminals, a holding member for holding the pair of external terminals, and a wiring section for electrically connecting the pair of external terminals to each other, a low-temperature chamber for housing the test specimen and cooling the test specimen to a first set temperature or lower, a current passing device electrically connected to the pair of external terminals and capable of passing current through the test specimen, a temperature sensor for detecting the temperature of at least one of the pair of external terminals, and a control unit for controlling the current passing device, wherein the control unit starts current passing by the current passing device when the detection value of the temperature sensor reaches the first set temperature, and stops current passing by the current passing device when the detection value of the temperature sensor reaches a second set temperature higher than the first set temperature.

[0035] In this thermal shock testing system, the current passing device starts to pass current when the detection value of the temperature sensor reaches a first set temperature, and stops passing current when the detection value of the temperature sensor reaches a second set temperature, thereby improving the accuracy of the thermal shock testing.

[0036] In addition, the storage cell unit may further include a pair of insulating members that are sandwiched between each of the pair of external terminals and the holding member, and that can be heated to the second set temperature by receiving heat from the external terminals when the external terminals are heated to the second set temperature.

[0037] In this embodiment, it is possible to carry out a thermal shock test on the insulating member in addition to the external terminal that can be heated by passing a current.

[0038] Moreover, it is preferable that the low-temperature chamber is configured as a constant temperature chamber that maintains the temperature therein at the first set temperature.

[0039] In this aspect, the energy storage cell unit is cooled simply by stopping the energization by the energizing device when the detected value of the temperature sensor reaches the second set temperature, and therefore the structure is simplified.

[0040] Furthermore, the thermal shock testing method in the above embodiment includes a placement step of placing a test specimen including a pair of external terminals, a holding member for holding the pair of external terminals, and a wiring portion electrically connecting the pair of external terminals to each other in a low-temperature chamber in which the temperature of the test specimen is cooled until the temperature of the test specimen becomes equal to or lower than a first set temperature, and a cycle testing step of alternately repeating the steps of: raising the temperature of the pair of external terminals by passing electricity through the test specimen when the temperature of at least one of the pair of external terminals in the low-temperature chamber reaches the first set temperature; and stopping the passage of electricity through the test specimen when the temperature of the one external terminal reaches a second set temperature higher than the first set temperature, and cooling the test specimen in the low-temperature chamber until the temperature of the one external terminal reaches the first set temperature.

[0041] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0042] 1 thermal shock test system, 10 test specimen, 12 external terminal, 14 holding member, 16 insulating member, 20 low temperature chamber, 30 temperature sensor, 40 current application device, 50 control unit.

Claims

1. a specimen including a pair of external terminals, a holding member for holding the pair of external terminals, and a wiring portion for electrically connecting the pair of external terminals; a low-temperature chamber containing the specimen and configured to cool the specimen to a first set temperature or lower; an energization device electrically connected to the pair of external terminals and capable of energizing the test piece; a temperature sensor for detecting a temperature of at least one of the pair of external terminals; A control unit that controls the energizing device, the control unit starts energization by the energizing device when a detection value of the temperature sensor reaches the first set temperature, and stops energization by the energizing device when a detection value of the temperature sensor reaches a second set temperature higher than the first set temperature; The thermal shock testing system further includes a pair of insulating members that are sandwiched between each of the pair of external terminals and the holding member, and that can be heated to the second set temperature by receiving heat from the external terminals when the external terminals are heated to the second set temperature.

2. 2. The thermal shock testing system of claim 1, wherein the low-temperature chamber is a constant temperature chamber that maintains an internal temperature at the first set temperature.

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