A device for testing the closed-pore rupture temperature of battery separators

Abstract

The present invention relates to the technical field of detection devices, and in particular to a device for testing the closed-pore rupture temperature of a battery diaphragm, comprising a high-temperature resistant tube, a first heating plate, an internal resistance analyzer, and a temperature controller connected to the control end of the first heating plate, the internal resistance analyzer is provided with a positive electrode plate and a negative electrode plate, the interior of the high-temperature resistant tube is provided with an electrolyte chamber, the two ends of the high-temperature resistant tube are respectively provided with a first opening and a second opening for connecting the electrolyte chamber with the outside of the high-temperature resistant tube, the first heating plate is connected to one end of the high-temperature resistant tube, the first heating plate and one end of the high-temperature resistant tube clamp the positive electrode plate, a first diaphragm placement space for placing a battery diaphragm is provided between the positive electrode plate and the first opening, the negative electrode plate is connected to the other end of the high-temperature resistant tube, and the negative electrode plate closes the second opening. The present invention can judge the closed-pore temperature and rupture temperature of the diaphragm according to the resistance change of the internal resistance analyzer, which is not only easy to operate, but also has a small error.

Description

Technical Field

[0001] The invention relates to the technical field of detection devices, and in particular to a device for testing the closed-pore rupture temperature of a battery separator. Background Art

[0002] As one of the four main materials of lithium-ion batteries, the separator has a great impact on the safety performance of the battery, especially the defective separator poses a great safety threat to the finished battery cells. Among them, the closed-pore and rupture temperatures of the separator are two physical and chemical parameters for judging the safety of lithium-ion battery separators. Accurately measuring the closed-pore and rupture temperatures has a very high guiding significance for the selection of separator materials. In traditional technology, the sample is generally heated to a series of temperatures, and then the air permeability after heating at each temperature is tested. If the air permeability is higher than 1000S, it is judged that the closed-pore temperature has been reached. When the air permeability suddenly decreases, it is judged that the rupture temperature has been reached. However, the use of traditional technology for measurement is not only inconvenient to operate, but also has large errors, resulting in inaccurate measurement results. Summary of the invention

[0003] In view of the problems of the prior art, the present invention provides a device for testing the closed-pore rupture temperature of a battery diaphragm, which is not only easy to operate but also has small errors and high measurement accuracy.

[0004] The present invention adopts the following technical scheme: a device for testing the closed-pore rupture temperature of a battery diaphragm, comprising a high-temperature resistant tube, a first heating plate, an internal resistance analyzer and a temperature controller connected to the control end of the first heating plate, the internal resistance analyzer is provided with a positive electrode plate and a negative electrode plate, the interior of the high-temperature resistant tube is provided with an electrolyte cavity, the two ends of the high-temperature resistant tube are respectively provided with a first opening and a second opening for connecting the electrolyte cavity with the outside of the high-temperature resistant tube, the first heating plate is connected to one end of the high-temperature resistant tube, the first heating plate and one end of the high-temperature resistant tube clamp the positive electrode plate, a first diaphragm placement space for placing a battery diaphragm is provided between the positive electrode plate and the first opening, the negative electrode plate is connected to the other end of the high-temperature resistant tube, and the negative electrode plate closes the second opening.

[0005] Preferably, the first heating plate is detachably connected to the high temperature resistant tube.

[0006] Preferably, the device for testing the closed-pore rupture temperature of the battery diaphragm further comprises a first screw, and the first heating plate is detachably connected to the one end of the high-temperature resistant tube via the first screw.

[0007] Preferably, the first screw passes through the positive electrode plate.

[0008] Preferably, the device for testing the closed-pore rupture temperature of the battery diaphragm also includes a second heating plate connected to the other end of the high-temperature resistant tube, the second heating plate and the other end of the high-temperature resistant tube clamp the negative electrode plate, and a second diaphragm placement space for placing the battery diaphragm is provided between the negative electrode plate and the second opening, and the temperature controller is connected to the control end of the second heating plate.

[0009] Preferably, the second heating plate is detachably connected to an end of the high temperature resistant tube away from the first heating plate.

[0010] Preferably, the device for testing the closed-pore rupture temperature of the battery diaphragm further comprises a second screw, and the second heating plate is detachably connected to the high-temperature resistant tube via the second screw.

[0011] Preferably, the second screw passes through the negative electrode plate.

[0012] The beneficial effects of the present invention are as follows: by using an internal resistance analyzer to measure the resistance of the battery diaphragm at different temperatures, the user can judge the pore closing temperature and membrane rupture temperature of the diaphragm according to the resistance change of the internal resistance analyzer, which is not only easy to operate but also has a small error. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an exploded view of the present invention.

[0014] The accompanying drawings are marked as follows: 1. high temperature resistant tube; 11. electrolyte chamber; 2. first heating plate; 3. internal resistance analyzer; 31. positive electrode plate; 32. negative electrode plate; 4. temperature controller; 5. first screw; 6. second heating plate; 7. second screw. DETAILED DESCRIPTION

[0015] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with the embodiments and drawings, and the contents mentioned in the embodiments are not intended to limit the present invention. The present invention is described in detail below in conjunction with the drawings.

[0016] like Figure 1As shown, a device for testing the closed-pore rupture temperature of a battery diaphragm comprises a high-temperature resistant tube 1, a first heating plate 2, an internal resistance analyzer 3 and a temperature controller 4 connected to the control end of the first heating plate 2, the internal resistance analyzer 3 is provided with a positive electrode plate 31 and a negative electrode plate 32, the interior of the high-temperature resistant tube 1 is provided with an electrolyte cavity 11, and the two ends of the high-temperature resistant tube 1 are respectively provided with a first opening and a second opening for connecting the electrolyte cavity 11 with the outside of the high-temperature resistant tube 1, the first heating plate 2 is connected to one end of the high-temperature resistant tube 1, the first heating plate 2 and one end of the high-temperature resistant tube 1 clamp the positive electrode plate 31, a first diaphragm placement space for placing a battery diaphragm is provided between the positive electrode plate 31 and the first opening, the negative electrode plate 32 is connected to the other end of the high-temperature resistant tube 1, and the negative electrode plate 32 closes the second opening.

[0017] When testing, first use the negative electrode plate 32 to close the second opening of the high temperature resistant tube 1, and inject the electrolyte into the electrolyte chamber 11 from the first opening; place the battery diaphragm in the first diaphragm placement space, and use the temperature controller 4 to control the temperature of the first heating plate 2, so that the first heating plate 2 is heated from 25°C to 160°C at a rate of 5°C / h. During the temperature change of the first heating plate 2, if the resistance value detected by the internal resistance analyzer 3 suddenly increases, the closed-cell temperature is reached, and if the resistance value detected by the internal resistance analyzer 3 suddenly decreases, the membrane breaking temperature is reached. The present invention is easy to use and convenient for batch testing of battery diaphragms. After testing a battery diaphragm, take the battery diaphragm out of the first diaphragm placement space and put it into another battery diaphragm. The temperature of the first heating plate 2 of the present invention changes linearly, and the battery diaphragm can be detected by the internal resistance analyzer 3 while being heated, thereby ensuring that the detection error of the present invention is small.

[0018] like Figure 1 As shown, the detachable connection between the first heating plate 2 and the high temperature resistant tube 1 makes it easy for the user to disassemble and install the first heating plate 2.

[0019] Specifically, the device for testing the closed-pore rupture temperature of the battery diaphragm also includes a first screw 5, and the first heating plate 2 is detachably connected to one end of the high-temperature resistant tube 1 through the first screw 5, thereby realizing the connection between the first heating plate 2 and the high-temperature resistant tube 1 using a simple structure.

[0020] like Figure 1 As shown, the first screw 5 passes through the positive electrode plate 31 to position the positive electrode plate 31, thereby preventing the positive electrode plate 31 from shifting by itself.

[0021] like Figure 1As shown, the device for testing the closed-pore rupture temperature of the battery diaphragm also includes a second heating plate 6 connected to one end of the high-temperature resistant tube 1 away from the first heating plate 2, the second heating plate 6 and one end of the high-temperature resistant tube 1 clamp the negative electrode plate 32, and a second diaphragm placement space for placing the battery diaphragm is provided between the negative electrode plate 32 and the second opening, and the temperature controller 4 is connected to the control end of the second heating plate 6. The present invention can also detect two identical battery diaphragms at the same time, thereby further improving the detection accuracy. The specific use process is: put a battery diaphragm into the second diaphragm placement space and connect the second heating plate 6 to the other end of the high-temperature resistant tube 1; inject electrolyte into the electrolyte chamber 11, and then put another battery diaphragm into the first diaphragm prevention space and connect the first heating plate 2 to the one end of the high-temperature resistant tube 1. The first heating plate 2 and the second heating plate 6 heat the two battery diaphragms respectively. Once one of the battery diaphragms undergoes a closed-pore or rupture change, the resistance detected by the internal resistance analyzer 3 will immediately change accordingly, thereby making the detection accuracy of the present invention higher.

[0022] like Figure 1 As shown, the second heating plate 6 is detachably connected to the high temperature resistant tube 1 to position the positive electrode plate 31 so that the user can disassemble and install the second heating plate 6 .

[0023] Specifically, the device for testing the closed-pore rupture temperature of the battery diaphragm also includes a second screw 7, and the second heating plate 6 is detachably connected to the other end of the high-temperature resistant tube 1 through the second screw 7, thereby realizing the connection between the second heating plate 6 and the high-temperature resistant tube 1 using a simple structure.

[0024] like Figure 1 As shown, the second screw 7 penetrates the negative electrode plate 32, thereby preventing the negative electrode plate 32 from shifting by itself.

[0025] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention is disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments according to the technology of the present invention are within the scope of the technical solution of the present invention without departing from the content of the technical solution of the present invention.

Claims

1. A device for testing the closed-pore rupture temperature of a battery diaphragm, characterized in that: The invention comprises a high temperature resistant tube (1), a first heating plate (2), an internal resistance analyzer (3), and a temperature controller (4) connected to the control end of the first heating plate (2); the internal resistance analyzer (3) is provided with a positive electrode plate (31) and a negative electrode plate (32); an electrolyte chamber (11) is provided inside the high temperature resistant tube (1); two ends of the high temperature resistant tube (1) are respectively provided with a first opening and a second opening for connecting the electrolyte chamber (11) with the outside of the high temperature resistant tube (1); the first heating plate (2) is connected to one end of the high temperature resistant tube (1); the first heating plate (2) and one end of the high temperature resistant tube (1) clamp the positive electrode plate (31); a first diaphragm placement space for placing a battery diaphragm is provided between the positive electrode plate (31) and the first opening; the negative electrode plate (32) is connected to the other end of the high temperature resistant tube (1); the negative electrode plate (32) closes the second opening; The first heating plate (2) is detachably connected to the high temperature resistant tube (1); The device for testing the closed-pore rupture temperature of a battery diaphragm further comprises a second heating plate (6) connected to the other end of the high-temperature resistant tube (1), the second heating plate (6) and the other end of the high-temperature resistant tube (1) clamp the negative electrode plate (32), a second diaphragm placement space for placing a battery diaphragm is provided between the negative electrode plate (32) and the second opening, and the temperature controller (4) is connected to the control end of the second heating plate (6); The second heating plate (6) is detachably connected to an end of the high temperature resistant tube (1) away from the first heating plate (2).

2. A device for testing the closed-pore rupture temperature of a battery separator according to claim 1, characterized in that: The device for testing the closed-pore rupture temperature of a battery diaphragm further comprises a first screw (5), and the first heating plate (2) is detachably connected to the one end of the high-temperature resistant tube (1) via the first screw (5).

3. A device for testing the closed-pore rupture temperature of a battery separator according to claim 2, characterized in that: The first screw (5) passes through the positive electrode plate (31).

4. The device for testing the closed-pore rupture temperature of a battery separator according to claim 1, characterized in that: The device for testing the closed-pore rupture temperature of a battery diaphragm further comprises a second screw (7), and the second heating plate (6) is detachably connected to the high-temperature resistant tube (1) via the second screw (7).

5. The device for testing the closed-pore rupture temperature of a battery separator according to claim 4, characterized in that: The second screw (7) passes through the negative electrode plate (32).

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