Thermal runaway characteristic testing device of soft package power lithium battery for aviation

Abstract

The invention discloses a thermal runaway characteristic testing device for a soft package power lithium battery for aviation, and relates to the field of lithium ion battery detection devices. The thermal runaway characteristic testing device for the soft package power lithium battery for aviation comprises a thermal runaway cabin, an explosion cabin and a conveying pipe, the conveying pipe is used for discharging a mixture in the thermal runaway cabin into the explosion cabin, observation doors are rotationally connected to the thermal runaway cabin and the explosion cabin, the thermal runaway characteristic testing device further comprises a placing plate located in the thermal runaway cabin, and the placing plate is used for placing the lithium battery; the clamping device is mounted on the placement plate, and the clamping device is used for clamping and fixing four corners of the lithium battery; the electric telescopic cylinder is installed on the thermal runaway cabin, and the telescopic end of the electric telescopic cylinder is located in the thermal runaway cabin; the lithium battery is stably fixed through the accurate corner clamping device, puncture and transverse plane structure reservation can be synchronously completed by matching with the puncture needle with the hollow cavity, and the structural collection integrity and the cabin sealing performance are guaranteed by combining the double electromagnetic adsorption rings and the sealing plate.

Description

Technical Field

[0001] This invention belongs to the technical field of lithium-ion battery testing devices, specifically, it relates to a testing device for the thermal runaway characteristics of soft-pack power lithium batteries for aviation. Background Technology

[0002] With the increasing demand for power sources in the aviation industry, soft-pack lithium batteries have been widely used due to their advantages such as high energy density and light weight. However, they are prone to thermal runaway in complex aviation environments (such as high temperature, vibration, and compression), which may lead to safety accidents such as combustion and explosion. Therefore, accurate testing of their thermal runaway characteristics has become the key to ensuring aviation safety.

[0003] Existing lithium battery thermal runaway testing devices typically trigger thermal runaway through puncture, which cannot preserve the transverse structure of the cell after puncture. This makes it difficult for researchers to trace the internal structural changes (such as the degree of separator damage and electrode contact status) in the initial stage of thermal runaway. This affects the guiding value of the test data for battery safety design and has certain shortcomings. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a lithium-ion battery testing device that can overcome or at least partially solve the above problems.

[0005] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by the present invention is: a thermal runaway characteristic testing device for aviation soft-pack power lithium batteries, including a thermal runaway chamber, an explosion chamber, and a delivery pipe, wherein the delivery pipe is used to discharge the mixture in the thermal runaway chamber into the explosion chamber, and both the thermal runaway chamber and the explosion chamber are rotatably connected to observation doors, and further includes: A placement plate, located inside the thermal runaway chamber, is used to place lithium batteries. A clamping device is mounted on the placement plate, and the clamping device is used to clamp and fix the four corners of the lithium battery; An electric telescopic cylinder is installed on the thermal runaway chamber, with the telescopic end of the electric telescopic cylinder located inside the thermal runaway chamber; A puncture needle is installed on the telescopic end of the electric telescopic cylinder. The puncture needle has a hollow chamber and openings at both the top and bottom. The bottom is a pointed end that serves as the entry point. A cavity is located on the placement plate, and the position of the cavity matches the puncture needle. The lithium battery is clamped and fixed by a clamping device, and then a puncture needle is inserted into the lithium battery. At the same time, the puncture needle is inserted into the hole, and the transverse structure inside the lithium battery will enter the cavity inside the puncture needle. Then the puncture needle will enter the hole.

[0006] Furthermore, a telescopic rod is fixedly connected to the bottom of the placement plate, and a placement ring is fixedly connected to the telescopic end of the telescopic rod. The placement ring contains an electromagnetic adsorption ring.

[0007] Furthermore, a telescopic rod two is fixedly connected to the bottom of the placement plate, and a sealing plate is fixedly connected to the telescopic end of the telescopic rod two. The sealing plate is used to seal the hole.

[0008] Furthermore, a mounting plate is fixedly connected to the telescopic end of the electric telescopic cylinder, and the mounting plate has an electromagnetic adsorption ring, with the puncture needle located inside the electromagnetic adsorption ring.

[0009] Furthermore, the clamping device includes a clamping telescopic cylinder and a clamping plate. The clamping telescopic cylinder is mounted on the placement plate, and the clamping plate is mounted on the telescopic end of the clamping telescopic cylinder.

[0010] Furthermore, two sets of auxiliary telescopic cylinders are rotatably connected to the telescopic end of the clamping telescopic cylinder. Both sets of auxiliary telescopic cylinders are rotatably connected to the clamping plate. Both sets of clamping plates are rotatably connected to the telescopic end of the clamping telescopic cylinder, and multiple sets of needles are installed at equal intervals on the clamping plate.

[0011] Furthermore, a rotating shaft is installed on the telescopic end of the clamping telescopic cylinder, and both sets of clamping plates are rotatably connected to the rotating shaft.

[0012] Furthermore, the placement plate is equipped with electrode posts for charging the lithium battery.

[0013] Furthermore, the thermal runaway chamber is equipped with a temperature sensor, a static pressure sensor, and a safety valve, while the explosion chamber is equipped with a temperature sensor, a dynamic pressure sensor, a safety valve, and an ignition electrode.

[0014] Furthermore, heaters and explosion-proof layers are installed in both the thermal runaway chamber and the explosion chamber.

[0015] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: The present invention achieves stable fixation of lithium battery through precise corner clamping device, and can simultaneously complete puncture and preservation of transverse structure by means of puncture needle with hollow cavity. Combined with double electromagnetic adsorption ring and sealing plate, it ensures the integrity of structural collection and the airtightness of the chamber. At the same time, it uses multiple sensors, safety valve and explosion-proof layer to ensure test safety. It can simulate multiple scenarios such as thermal runaway and corner puncture, and can completely transfer the ejected material to the explosion chamber for combustion and explosion test, providing more accurate and comprehensive experimental data support for the study of thermal runaway characteristics of soft pack power lithium battery for aviation. Attached Figure Description

[0016] In the attached diagram: Figure 1This is a schematic diagram of the structure of the thermal runaway characteristic testing device for aviation soft-pack power lithium batteries proposed in this invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the thermal runaway characteristic testing device for aviation soft-pack power lithium batteries proposed in this invention. Figure 2 ; Figure 3 This is a schematic cross-sectional view of the thermal runaway characteristic testing device for aviation soft-pack power lithium batteries proposed in this invention. Figure 1 ; Figure 4 The present invention provides a testing device for the thermal runaway characteristics of soft-pack power lithium batteries for aviation applications. Figure 3 A schematic diagram of the structure of part A; Figure 5 This is a schematic cross-sectional view of the thermal runaway characteristic testing device for aviation soft-pack power lithium batteries proposed in this invention. Figure 2 ; Figure 6 The present invention provides a testing device for the thermal runaway characteristics of soft-pack power lithium batteries for aviation applications. Figure 5 A structural diagram of section B; Figure 7 The present invention provides a testing device for the thermal runaway characteristics of soft-pack power lithium batteries for aviation applications. Figure 5 A structural diagram of section C; Figure 8 This is a cross-sectional schematic diagram of the thermal runaway chamber in the thermal runaway characteristic testing device for aviation soft-pack power lithium batteries proposed in this invention. Figure 9 The present invention provides a testing device for the thermal runaway characteristics of soft-pack power lithium batteries for aviation applications. Figure 8 A schematic diagram of the structure of part D.

[0017] In the diagram: 1. Thermal runaway chamber; 101. Placement plate; 102. Hole; 103. Heater; 104. Explosion-proof layer; 2. Explosion chamber; 3. Delivery pipe; 4. Observation door; 501. Electric telescopic cylinder; 502. Mounting plate; 503. Puncture needle; 504. Placement ring; 505. Telescopic rod one; 506. Telescopic rod two; 507. Sealing plate; 601. Temperature sensor one; 602. Static pressure sensor; 603. Safety valve one; 701. Temperature sensor two; 702. Dynamic pressure sensor; 703. Safety valve two; 704. Ignition electrode; 801. Clamping telescopic cylinder; 802. Clamping plate; 803. Auxiliary telescopic cylinder; 804. Rotating shaft; 9. Electrode column. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0019] Example: Refer to Figure 1 , Figure 2 , Figure 3 , Figure 5 A thermal runaway characteristic testing device for aviation soft-pack power lithium batteries includes a thermal runaway chamber 1, an explosion chamber 2, and a delivery pipe 3. The delivery pipe 3 is used to discharge the mixture in the thermal runaway chamber 1 into the explosion chamber 2. Observation doors 4 are rotatably connected to both the thermal runaway chamber 1 and the explosion chamber 2. The device also includes: a placement plate 101 located inside the thermal runaway chamber 1 for placing lithium batteries; a clamping device mounted on the placement plate 101 for clamping and fixing the four corners of the lithium batteries; and an electric telescopic cylinder 501 mounted on the thermal runaway chamber 1, with the telescopic end of the electric telescopic cylinder 501 located at the thermal runaway chamber. Inside compartment 1; a puncture needle 503 is installed on the telescopic end of the electric telescopic cylinder 501. The puncture needle 503 has a hollow chamber and openings at both the top and bottom, with the pointed bottom being the entry end; a hole 102 is located on the placement plate 101, and the position of the hole 102 matches that of the puncture needle 503; the lithium battery is clamped and fixed by a clamping device, and then the puncture needle 503 penetrates the lithium battery while simultaneously inserting into the hole 102. At this time, the transverse structure inside the lithium battery will enter the chamber inside the puncture needle 503, and then the puncture needle 503 will enter the hole 102.

[0020] Among them, such as Figure 1 , Figure 4 As shown, the thermal runaway chamber 1 and the explosion chamber 2 are connected by a delivery pipe 3, which is used to discharge the mixture generated by the thermal runaway of the lithium battery in the thermal runaway chamber 1 into the explosion chamber 2. Both the thermal runaway chamber 1 and the explosion chamber 2 are rotatably connected to observation doors 4. The observation doors 4 are made of high-strength transparent explosion-proof glass, which can ensure that the operators can clearly observe the situation inside the chamber, and also has sufficient strength and explosion-proof performance. A sealing ring is set at the connection between the observation door 4 and the chamber body to further enhance the sealing effect, prevent gas leakage inside the chamber, and facilitate the operators to observe the situation inside the chamber and perform operations such as placing lithium batteries and maintaining the equipment.

[0021] Specifically, such as Figure 2 , Figure 3 As shown, the delivery pipe 3 is made of an alloy material that is resistant to high temperature and high pressure and has good sealing performance. Its inner wall is smooth, which can effectively reduce the residue and adhesion of the ejected material during the transmission process. At the same time, the delivery pipe 3 can also be optionally equipped with a flow monitoring component to monitor the transmission flow of the ejected material in real time, so as to more accurately grasp the release of thermal runaway ejected material, and set a control valve to control the entry and exit of gas and liquid.

[0022] A telescopic rod 505 is fixedly connected to the bottom of the placement plate 101. A placement ring 504 is fixedly connected to the telescopic end of the telescopic rod 505. An electromagnetic adsorption ring is located inside the placement ring 504. A second telescopic rod 506 is fixedly connected to the bottom of the placement plate 101. A sealing plate 507 is fixedly connected to the telescopic end of the second telescopic rod 506. The sealing plate 507 is used to seal the hole 102.

[0023] Among them, such as Figure 3 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 As shown, an installation plate 502 is fixedly connected to the telescopic end of the electric telescopic cylinder 501. The installation plate 502 has an electromagnetic adsorption ring, and the puncture needle 503 is located inside the electromagnetic adsorption ring. The clamping device includes a clamping telescopic cylinder 801 and a clamping plate 802. The clamping telescopic cylinder 801 is installed on the placement plate 101, and the clamping plate 802 is installed on the telescopic end of the clamping telescopic cylinder 801. Two sets of auxiliary telescopic cylinders 803 are rotatably connected to the telescopic end of the clamping telescopic cylinder 801. Both sets of auxiliary telescopic cylinders 803 are rotatably connected to the clamping plate 802. Both sets of clamping plates 802 are rotatably connected to the telescopic end of the clamping telescopic cylinder 801, and multiple sets of puncture needles are installed at equal intervals on the clamping plate 802.

[0024] A rotating shaft 804 is installed on the telescopic end of the clamping telescopic cylinder 801. Both sets of clamping plates 802 are rotatably connected to the rotating shaft 804. An electrode post 9 for charging the lithium battery is installed on the placement plate 101.

[0025] Furthermore, such as Figure 5 As shown, thermal runaway chamber 1 is equipped with temperature sensor 601, static pressure sensor 602, and safety valve 603, while explosion chamber 2 is equipped with temperature sensor 701, dynamic pressure sensor 702, safety valve 703, and ignition electrode 704. Both thermal runaway chamber 1 and explosion chamber 2 are equipped with heater 103 and explosion-proof layer 104.

[0026] Specifically, at this time, such as Figure 5 As shown, the thermal runaway chamber 1 is equipped with a temperature sensor 601, a static pressure sensor 602, and a safety valve 603. The temperature sensor 601 is a high-precision thermocouple temperature sensor that can monitor the temperature changes inside the thermal runaway chamber 1 in real time and accurately. It has a wide measurement range and is suitable for the high-temperature environment during thermal runaway. The static pressure sensor 602 is a high-sensitivity piezoresistive pressure sensor that can accurately measure the static pressure inside the thermal runaway chamber 1. The safety valve 603 is a spring-loaded safety valve that can automatically open to release pressure when the pressure inside the thermal runaway chamber 1 exceeds the set safety threshold, ensuring the safety of the thermal runaway chamber 1.

[0027] More specifically, at this time, such as Figure 5 As shown, the explosion chamber 2 is equipped with a second temperature sensor 701, a dynamic pressure sensor 702, a second safety valve 703, and an ignition electrode 704. The second temperature sensor 701 has similar performance to the first temperature sensor 601 and is used to monitor the temperature inside the explosion chamber 2. The dynamic pressure sensor 702 is a high-frequency response piezoelectric pressure sensor that can quickly capture dynamic pressure changes inside the explosion chamber 2 and provide data support for the analysis of combustion and explosion characteristics. The second safety valve 703 has similar function to the first safety valve 603 and ensures the safety of the explosion chamber 2. The ignition electrode 704 is a high-voltage discharge ignition electrode that can generate a high-intensity electric spark to reliably ignite the thermal runaway mixture of lithium batteries delivered to the explosion chamber 2.

[0028] In actual use, the staff first places the aviation soft-pack power lithium battery on the placement plate 101, starts the clamping device, and the clamping telescopic cylinder 801 moves, driving the two sets of clamping plates 802 to approach the lithium battery. The auxiliary telescopic cylinder 803 adjusts the angle of the clamping plates 802 so that the two sets of clamping plates 802 accurately clamp and fix the four corners of the lithium battery.

[0029] The lithium battery is heated by the heater 103 inside the thermal runaway chamber 1. Once the lithium battery bulges, a puncture operation is prepared.

[0030] The electric telescopic cylinder 501 actuates, causing the mounting plate 502 and the adsorbed puncture needle 503 to move downwards. The pointed bottom of the puncture needle 503 penetrates the lithium battery and simultaneously inserts into the cavity 102. At this time, the transverse structure inside the lithium battery enters the cavity of the puncture needle 503. Subsequently, the telescopic rod 505 actuates, causing the placement ring 504 to move upwards. The electromagnetic adsorption ring inside the placement ring 504 adsorbs and fixes the puncture needle 503. Then, the electric telescopic cylinder 501 actuates, causing the mounting plate 502 to move downwards, separating the puncture needle 503 from the mounting plate 502. At this time, the electromagnet inside the mounting plate 502 is de-energized, facilitating separation. Finally, the telescopic rod 506 actuates, causing the sealing plate 507 to move upwards, sealing the cavity 102.

[0031] As the mounting plate 502 moves away, the thermal runaway of the lithium battery will generate ejected material, which will be transported to the explosion chamber 2 through the delivery pipe 3 and finally detonated by the ignition electrode 704.

[0032] Specifically, when performing the lithium battery corner piercing and subsequent detonation operation, the corner of the lithium battery is first pierced using the piercing pin on the clamping plate 802 of the clamping device. At this time, inside the thermal runaway chamber 1, the lithium battery undergoes a thermal runaway reaction due to the corner being pierced, producing a jet containing flammable gas, electrolyte and other components.

[0033] The lithium battery thermal runaway ejection material delivered to the explosion chamber 2 is ignited by the ignition electrode 704 on the explosion chamber 2 and ignited by discharge or other means, thereby allowing for testing and research on its combustion and explosion characteristics.

[0034] After the thermal runaway reaction of the lithium battery in the thermal runaway chamber 1 has ended and the temperature and pressure inside the chamber have dropped to a safe range (which can be monitored in real time by temperature sensor 601 and static pressure sensor 602 to ensure that the temperature is ≤50℃ and the pressure is equal to atmospheric pressure), the operator first turns off the main power supply of the device, and then observes the internal status through the observation door 4 on the thermal runaway chamber 1. After confirming that there is no risk of leakage of residual ejected material, the observation door 4 is opened.

[0035] Subsequently, the sealing plate 507 moves away from the hole 102 and controls the telescopic rod 505 to move, causing the placement ring 504 and the adsorbed and fixed puncture needle 503 to move upward synchronously until the puncture needle 503 extends out of the hole 102. Then, the power supply of the electromagnetic adsorption ring in the placement ring 504 is turned off, releasing the adsorption and fixation of the puncture needle 503. The operator uses special insulated tweezers (to avoid electrolyte corrosion or residual charge) to remove the puncture needle 503 from the thermal runaway chamber 1.

[0036] After removing the puncture needle 503, its exterior must be cleaned: use a lint-free cloth dampened with anhydrous ethanol to gently wipe the outer surface of the puncture needle 503 to remove residual electrolyte or dust and prevent contamination of the internal battery cell structure.

[0037] After cleaning, the puncture needle 503 is placed with its pointed end facing upwards on a dedicated support. The internal cell cross-sectional structure is observed through the opening at the top of the puncture needle 503 using high-precision microscopic imaging equipment (such as a super depth-of-field microscope or a scanning electron microscope). The layering state of the positive electrode, separator, and negative electrode is recorded, and key parameters such as the damaged area of ​​the separator and the degree of deformation of the electrode materials are measured. If component analysis is required, a micro-sampling tool (such as an ultrafine probe) can be used to extract trace samples from the cross-sectional structure. The changes in the crystal structure of the electrode materials and the composition of electrolyte decomposition products are detected by equipment such as X-ray diffractometer and energy dispersive spectroscopy. This allows for the establishment of a correlation model of "puncture damage - structural change - thermal runaway induction," providing microscopic data support for optimizing the safety performance of lithium batteries.

[0038] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A thermal runaway characteristic testing device for aviation soft-pack power lithium batteries, comprising a thermal runaway chamber (1), an explosion chamber (2), and a delivery pipe (3), wherein the delivery pipe (3) is used to discharge the mixture in the thermal runaway chamber (1) into the explosion chamber (2), and both the thermal runaway chamber (1) and the explosion chamber (2) are rotatably connected to observation doors (4), characterized in that, Also includes: A placement plate (101) is located inside the thermal runaway chamber (1), and the placement plate (101) is used to place lithium batteries; A clamping device is installed on the placement plate (101) and is used to clamp and fix the four corners of the lithium battery. An electric telescopic cylinder (501) is installed on the thermal runaway chamber (1), and the telescopic end of the electric telescopic cylinder (501) is located inside the thermal runaway chamber (1); A puncture needle (503) is installed on the telescopic end of the electric telescopic cylinder (501). The puncture needle (503) has a hollow chamber and openings at both the top and bottom. The bottom is a pointed end that is the entry end. A hole (102) is located on the placement plate (101), and the position of the hole (102) matches that of the puncture needle (503); The lithium battery is clamped and fixed by the clamping device, and then the lithium battery is penetrated by the puncture needle (503). At the same time, the puncture needle (503) is inserted into the hole (102). At this time, the transverse structure inside the lithium battery will enter the cavity inside the puncture needle (503), and then the puncture needle (503) will enter the hole (102).

2. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 1, characterized in that, The bottom of the placement plate (101) is fixedly connected to a telescopic rod (505), and a placement ring (504) is fixedly connected to the telescopic end of the telescopic rod (505). The placement ring (504) has an electromagnetic adsorption ring inside.

3. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 2, characterized in that, The bottom of the placement plate (101) is fixedly connected to a telescopic rod two (506), and a sealing plate (507) is fixedly connected to the telescopic end of the telescopic rod two (506). The sealing plate (507) is used to seal the hole (102).

4. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 3, characterized in that, An installation plate (502) is fixedly connected to the telescopic end of the electric telescopic cylinder (501). The installation plate (502) has an electromagnetic adsorption ring, and the puncture needle (503) is located inside the electromagnetic adsorption ring.

5. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 1, characterized in that, The clamping device includes a clamping telescopic cylinder (801) and a clamping plate (802). The clamping telescopic cylinder (801) is mounted on the placement plate (101), and the clamping plate (802) is mounted on the telescopic end of the clamping telescopic cylinder (801).

6. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 5, characterized in that, Two sets of auxiliary telescopic cylinders (803) are rotatably connected to the telescopic end of the clamping telescopic cylinder (801). Both sets of auxiliary telescopic cylinders (803) are rotatably connected to the clamping plate (802). Both sets of clamping plates (802) are rotatably connected to the telescopic end of the clamping telescopic cylinder (801). Multiple sets of needles are installed at equal intervals on the clamping plate (802).

7. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 6, characterized in that, The telescopic end of the clamping telescopic cylinder (801) is equipped with a rotating shaft (804), and both sets of clamping plates (802) are rotatably connected to the rotating shaft (804).

8. The thermal runaway characteristic testing device for aviation soft-pack power lithium batteries according to claim 5, characterized in that, The placement plate (101) is equipped with electrode posts (9) for charging the lithium battery.

9. The device for testing the thermal runaway characteristics of a soft-pack power lithium battery for aviation use according to claim 1, characterized in that, The thermal runaway chamber (1) is equipped with a temperature sensor (601), a static pressure sensor (602), and a safety valve (603). The explosion chamber (2) is equipped with a temperature sensor (701), a dynamic pressure sensor (702), a safety valve (703), and an ignition electrode (704).

10. The device for testing the thermal runaway characteristics of a soft-pack power lithium battery for aviation use according to claim 9, characterized in that, The thermal runaway chamber (1) and the explosion chamber (2) are both equipped with heaters (103) and explosion-proof layers (104).

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