A lithium battery thermal runaway trigger and fast interrupt measurement device and method

Abstract

The present application relates to a kind of lithium battery thermal runaway trigger and fast interruption measuring device and method, the measuring device is closed device, comprising: normally closed cover, first pressure sensor and air inlet and exhaust electromagnetic valve are arranged on it;For placing the metal main tank of lithium battery to be measured, inside sleeve is set with metal inner container, the metal inner container is covered with electric heating tube and temperature sensor, cooling device for quickly interrupting the thermal runaway process of lithium battery to be measured is arranged in the metal inner container;Sample cover, second pressure sensor is arranged on it;Needle assembly is arranged on the metal main tank, for triggering lithium battery to be measured thermal runaway and the lithium battery to be measured of triggering thermal runaway is punctured and vented.Compared with prior art, the present application realizes the triggering and fast interruption of multiple forms of thermal runaway of full-size lithium battery, so as to carry out material state acquisition and gas production state test in each stage of thermal runaway.

Description

Technical Field

[0001] This invention relates to the field of lithium battery testing technology, and in particular to a lithium battery thermal runaway triggering and rapid interruption measurement device and method. Background Technology

[0002] In recent years, the lithium-ion power battery industry has experienced rapid development, achieving a world-leading scale and becoming a core driving force for the electrification of automobiles. However, frequent fire accidents have impacted users' confidence in the safety and durability of new energy vehicles.

[0003] During thermal runaway, lithium-ion batteries undergo a series of chemical reactions, including separator shrinkage, electrolyte decomposition, and positive and negative electrode decomposition, generating a large amount of heat and flammable gases. The high temperature and pressure generated after thermal runaway of a cell within a module can damage the battery pack. Evaluating the material changes, gas generation patterns, and gas composition at different stages of thermal runaway in lithium batteries is of great significance for lithium battery research.

[0004] Current experimental methods for analyzing battery thermal runaway involve measuring pressure, temperature, and voltage in a sealed container. However, this method neglects material changes and gas generation at each stage of thermal runaway, failing to accurately reflect the true state of the battery at each stage. Furthermore, with the increasing size of individual battery cells, some equipment is no longer sufficient to meet the requirements for size and gas generation testing. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art by providing a lithium battery thermal runaway triggering and rapid interruption measurement device and method, which realizes multiple forms of thermal runaway triggering and rapid interruption of full-size lithium batteries, and obtains the test of material state and gas generation state at each stage of thermal runaway.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] According to a first aspect of the present invention, a lithium battery thermal runaway triggering and rapid interruption measuring device is provided, the measuring device being a hermetically sealed device comprising:

[0008] The normally closed cover is equipped with a first pressure sensor and an intake / exhaust solenoid valve.

[0009] The main metal housing for holding the lithium battery under test is fitted with a metal inner liner. The metal inner liner is covered with an electric heating tube and a temperature sensor. The metal inner liner is equipped with a cooling device for quickly interrupting the thermal runaway process of the lithium battery under test.

[0010] The sample inlet cap is equipped with a second pressure sensor and multiple spare interfaces.

[0011] The needle-punching assembly, mounted on the metal main casing, is used to trigger thermal runaway of the lithium battery under test and to puncture and release gas from the lithium battery under test that has triggered thermal runaway.

[0012] Preferably, the cooling device includes a detachable liquid cooling coil and a vacuum liquid nitrogen pipe;

[0013] The detachable liquid cooling coil is connected to the coolant inlet and outlet on the sample inlet cover; the vacuum liquid nitrogen tube is connected to the cryogenic liquid nitrogen ball valve on the sample inlet cover.

[0014] Preferably, a fireproof and heat-insulating layer is filled between the electric heating tube and the metal inner liner.

[0015] Preferably, the normally closed cover is further provided with a safety valve, a lighting device, a monitoring device, and a first temperature high-pressure component;

[0016] The sample inlet cover is also equipped with a second temperature and high pressure component of the same model as the first temperature and high pressure component.

[0017] The measuring device is a horizontal cylindrical structure.

[0018] Preferably, the metal liner can be filled with different inert gases depending on the test conditions.

[0019] Preferably, the needle insertion assembly includes a servo motor and a steel needle using the servo motor to control the insertion depth.

[0020] According to a second aspect of the present invention, a method for triggering and rapidly interrupting thermal runaway in a lithium battery is provided, employing any of the measuring devices described in the present invention, wherein the method comprises:

[0021] 1) Place the lithium battery to be tested into the measuring device;

[0022] 2) The cavity is heated by the built-in electric heating tube to trigger thermal runaway. Heating stops when the lithium battery experiences thermal runaway or reaches the preset program requirements; or the lithium battery under test is punctured by the needle puncture component to trigger thermal runaway. Puncture stops when the battery experiences thermal runaway or reaches the preset program requirements.

[0023] 3) After the thermal runaway process of the lithium battery reaches a preset state, the lithium battery under test that is experiencing thermal runaway is cooled by a cooling device; the thermal runaway is interrupted and the lithium battery under test enters a stable state.

[0024] 4) Collect temperature data, voltage data, pressure data, and gas data inside the chamber to monitor the status of the lithium battery under test.

[0025] According to a third aspect of the present invention, a method for triggering and rapidly interrupting thermal runaway in a lithium battery is provided, employing the aforementioned measuring device, wherein the method comprises:

[0026] 1) Place the lithium battery to be tested into the measuring device;

[0027] 2) Use the spare interface to bring out the positive and negative terminals of the lithium battery under test, charge it through an external charging device, trigger thermal runaway through a preset overcharge program; stop charging after the battery thermal runaway occurs or the preset program requirements are met.

[0028] 3) After the thermal runaway process of the lithium battery reaches a preset state, the lithium battery under test that is experiencing thermal runaway is cooled by a cooling device; the thermal runaway is interrupted and the lithium battery under test enters a stable state.

[0029] 4) Collect temperature data, voltage data, pressure data, and gas data inside the chamber to monitor the status of the lithium battery under test.

[0030] According to a fourth aspect of the present invention, a method for collecting and testing thermal runaway gases from a lithium battery is provided, the method comprising:

[0031] 1) Trigger thermal runaway and interrupt thermal runaway of the lithium battery under test according to any one of the methods described;

[0032] 2) By puncturing the explosion-proof valve port of the lithium battery under test in the needle puncture assembly, the gas generated by the lithium battery under test during thermal runaway is released into the inert gas environment inside the metal main box.

[0033] 3) Collect the gas in the cavity through the intake and exhaust solenoid valves, and perform gas testing using analysis equipment.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] 1) This invention enables multiple forms of triggering and rapid interruption of thermal runaway in lithium batteries, facilitating the acquisition of material states and testing of gas generation states at each stage of thermal runaway;

[0036] 2) The measuring device is a sealed device, which can replace the inside of the device with inert gas to eliminate the influence of air on the inaccurate measurement of gas composition during thermal runaway, making the gas production measurement results more accurate;

[0037] 3) The measuring device is a flat cylindrical structure, which can meet most current battery testing needs while ensuring accurate and sensitive pressure. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the measuring device structure of the present invention;

[0039] Figure 2A detailed structural diagram of the normally closed thimble;

[0040] Figure 3 This is a detailed structural diagram of the sample inlet cap;

[0041] Figure 4 This is a schematic diagram of the cross-section of the main metal enclosure;

[0042] Reference numerals: 1-Normally closed cover, 11-Safety valve, 12-Lighting device, 13-Monitoring device, 14-First pressure sensor, 15-Inlet / outlet solenoid valve, 16-First temperature and high pressure assembly; 2-Metal main body, 21-Fireproof insulation layer, 22-Electric heating tube, 23-Temperature sensor, 24-Metal inner liner, 25-Removable liquid cooling coil, 26-Vacuum liquid nitrogen tube; 3-Sample inlet cover, 31-Cryogenic liquid nitrogen ball valve, 32-Coolant inlet / outlet, 33-Second pressure sensor, 34-Second temperature and high pressure assembly, 35-Spare interface. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0044] Example

[0045] This invention provides a measurement device and method for triggering and rapidly interrupting thermal runaway in lithium batteries, in order to solve the problem that existing measurement technologies cannot test and analyze materials and gases at different stages of thermal runaway development in batteries.

[0046] First, an embodiment of the device of the present invention is given: a lithium battery thermal runaway triggering and rapid interruption measurement device, wherein the measurement device is a sealed device, comprising:

[0047] The normally closed cover 1 is equipped with a safety valve 11, a lighting device 12, a monitoring device 13, a first pressure sensor 14, an intake and exhaust solenoid valve 15, and a first temperature and high pressure component 16.

[0048] The main metal housing 2 is used to hold the lithium battery under test. An inner metal liner 24 is fitted inside the inner metal liner 24. An electric heating element 22 and a temperature sensor 23 are installed on the outside of the inner metal liner 24. A fireproof and heat-insulating layer 21 is filled between the electric heating element 22 and the inner metal liner 24. A cooling device is installed inside the inner metal liner 24 to quickly interrupt the thermal runaway process of the lithium battery under test. The cooling device includes a detachable liquid cooling coil 25 and a vacuum liquid nitrogen tube 26. The detachable liquid cooling coil 25 is connected to the coolant inlet / outlet 32 ​​on the sample inlet cover 3. The vacuum liquid nitrogen tube 26 is connected to a cryogenic liquid nitrogen ball valve 31 on the sample inlet cover 3. The inner metal liner 24 is filled with inert gas.

[0049] The sample inlet cover 3 is equipped with a cryogenic liquid nitrogen ball valve 31, a coolant inlet / outlet 32, a second pressure sensor 33, a second temperature and high pressure component 34, and multiple spare interfaces 35.

[0050] The needle-piercing assembly 4, which is mounted on the metal main housing 2, includes a servo motor and a steel needle that uses the servo motor to control the piercing depth. It is used to trigger the thermal runaway of the lithium battery under test and to puncture and release the lithium battery under test that has triggered thermal runaway.

[0051] Furthermore, the measuring device in this embodiment is a flat cylindrical structure with a diameter of 500mm and a length of 1500mm, which can be adapted to full-size lithium battery testing.

[0052] Next, an embodiment of the method of the present invention is given, a method for triggering and rapidly interrupting thermal runaway of a lithium battery, using any of the measuring devices described in the present invention, the method being as follows:

[0053] 1) Place the lithium battery to be tested into the measuring device;

[0054] 2) The cavity is heated by the built-in electric heating tube 22 to trigger thermal runaway. Heating stops when the lithium battery experiences thermal runaway or reaches the preset program requirements; or the test lithium battery is punctured by the needle puncture component 4 to trigger thermal runaway. Puncture stops when the battery experiences thermal runaway or reaches the preset program requirements.

[0055] 3) After the thermal runaway process of the lithium battery reaches the preset state, the lithium battery under test is cooled by a cooling device until the thermal runaway is interrupted and the lithium battery under test enters a stable state.

[0056] 4) Collect temperature data, voltage data, pressure data, and gas data inside the chamber to monitor the status of the lithium battery under test.

[0057] Next, another method embodiment of the present invention is given, a method for triggering and rapidly interrupting thermal runaway of a lithium battery, using the aforementioned measuring device, the method being as follows:

[0058] 1) Place the lithium battery to be tested into the measuring device;

[0059] 2) Use the spare interface 35 to bring out the positive and negative terminals of the lithium battery under test, charge it through an external charging device, trigger thermal runaway through a preset overcharge program; stop charging after the battery thermal runaway occurs or the preset program requirements are met.

[0060] 3) After the thermal runaway process of the lithium battery reaches a preset state, the lithium battery under test that is experiencing thermal runaway is cooled by a cooling device; the thermal runaway is interrupted and the lithium battery under test enters a stable state.

[0061] 4) Collect temperature data, voltage data, pressure data, and gas data inside the chamber to monitor the status of the lithium battery under test.

[0062] Next, a method for collecting and testing thermal runaway gases from lithium batteries is presented. The method is as follows:

[0063] 1) Trigger thermal runaway and interrupt thermal runaway in the lithium battery under test using any of the methods described above;

[0064] 2) By puncturing the explosion-proof valve port of the lithium battery under test in the needle puncture assembly 4, the gas generated by the lithium battery under test during thermal runaway is released into the inert gas environment inside the metal main box 2.

[0065] 3) Collect the gas in the cavity through the intake and exhaust solenoid valve 15, and perform gas testing using analysis equipment.

[0066] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for triggering and rapidly interrupting thermal runaway in a lithium battery, characterized in that, A lithium battery thermal runaway triggering and rapid interruption measurement device is applied, wherein the measurement device is a sealed device, comprising: Normally closed cover (1), on which a first pressure sensor (14) and an intake and exhaust solenoid valve (15) are provided. The main metal housing (2) for placing the lithium battery under test is fitted with a metal inner liner (24). The metal inner liner (24) is covered with an electric heating tube (22) and a temperature sensor (23). The metal inner liner (24) is equipped with a cooling device for quickly interrupting the thermal runaway process of the lithium battery under test. The sample inlet cap (3) is equipped with a second pressure sensor (33) and multiple spare interfaces (35). The needle-punching assembly (4) installed on the metal main housing (2) is used to trigger the thermal runaway of the lithium battery under test and to puncture and release the lithium battery under test that has triggered thermal runaway. The method is as follows: 1) Place the lithium battery to be tested into the measuring device; 2) The cavity is heated by the built-in electric heating tube (22) to trigger thermal runaway. Heating is stopped after the lithium battery has thermal runaway or reaches the preset program requirements; or the needle puncture assembly (4) is used to puncture the lithium battery under test to trigger thermal runaway. Puncture is stopped after the lithium battery under test has thermal runaway or reaches the preset program requirements. 3) After the thermal runaway process of the lithium battery reaches a preset state, the lithium battery under test is cooled by a cooling device until the thermal runaway of the lithium battery under test is interrupted and enters a stable state. 4) Collect temperature data, voltage data, pressure data, and gas data inside the chamber to monitor the status of the lithium battery under test.

2. A method for triggering and rapidly interrupting thermal runaway in a lithium battery, characterized in that, A lithium battery thermal runaway triggering and rapid interruption measurement device is applied, wherein the measurement device is a sealed device, comprising: Normally closed cover (1), on which a first pressure sensor (14) and an intake and exhaust solenoid valve (15) are provided. The main metal housing (2) for placing the lithium battery under test is fitted with a metal inner liner (24). The metal inner liner (24) is covered with an electric heating tube (22) and a temperature sensor (23). The metal inner liner (24) is equipped with a cooling device for quickly interrupting the thermal runaway process of the lithium battery under test. The sample inlet cap (3) is equipped with a second pressure sensor (33) and multiple spare interfaces (35). The needle-punching assembly (4) installed on the metal main housing (2) is used to trigger the thermal runaway of the lithium battery under test and to puncture and release the lithium battery under test that has triggered thermal runaway. The method is as follows: 1) Place the lithium battery to be tested into the measuring device; 2) Use the spare interface (35) to bring out the positive and negative terminals of the lithium battery under test, charge it through an external charging device, trigger thermal runaway through a preset overcharge program; stop charging after the lithium battery under test has thermal runaway or has reached the preset program requirements. 3) After the thermal runaway process of the lithium battery reaches a preset state, the lithium battery under test is cooled by a cooling device until the thermal runaway of the lithium battery under test is interrupted and enters a stable state. 4) Collect temperature data, voltage data, pressure data, and gas data inside the chamber to monitor the status of the lithium battery under test.

3. The method according to claim 1 or 2, characterized in that, The cooling device includes a detachable liquid cooling coil (25) and a vacuum liquid nitrogen pipe (26). The detachable liquid cooling coil (25) is connected to the coolant inlet and outlet (32) provided on the sample inlet cover (3); the vacuum liquid nitrogen tube (26) is connected to the cryogenic liquid nitrogen ball valve (31) provided on the sample inlet cover (3).

4. The method according to claim 1 or 2, characterized in that, A fireproof and heat-insulating layer (21) is filled between the electric heating tube (22) and the metal inner liner (24).

5. The method according to claim 1 or 2, characterized in that, The normally closed cover (1) is also equipped with a safety valve (11), a lighting device (12), a monitoring device (13), and a first temperature and high pressure component (16). The sample inlet cover (3) is also equipped with a second temperature and high pressure component (34) of the same model as the first temperature and high pressure component (16).

6. The method according to claim 1 or 2, characterized in that, The measuring device is a horizontal cylindrical structure.

7. The method according to claim 1 or 2, characterized in that, The metal liner (24) can be filled with different inert gases depending on the test conditions.

8. The method according to claim 1 or 2, characterized in that, The needle insertion assembly (4) includes a servo motor and a steel needle that uses the servo motor to control the insertion depth.

9. A method for collecting and testing thermal runaway gases from lithium batteries, characterized in that, The method is as follows: 1) Triggering and interrupting thermal runaway of the lithium battery under test according to any one of claims 1 or 2; 2) By puncturing the explosion-proof valve port of the lithium battery under test in the needle puncture assembly (4), the gas generated by the lithium battery under test during thermal runaway is released into the inert gas environment inside the metal main box (2). 3) Collect the gas in the cavity through the intake and exhaust solenoid valve (15) and perform gas testing using analysis equipment.

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