Battery thermal runaway pressure measuring device and battery thermal runaway pressure measuring method

Abstract

The present invention relates to a battery thermal runaway pressure measuring device and a battery thermal runaway pressure measuring method. The battery thermal runaway pressure measuring device includes a fixture and a pressure gauge; the fixture is used to connect the battery; the pressure gauge includes a main body, a sensing head and an air inlet, the sensing head is connected to the end of the main body, and the sensing head is connected to the fixture, and the air inlet is located on the end face of the sensing head; the air inlet is used to connect to a measuring hole opened on one side of the battery and connected to the inside of the battery, so as to measure the internal pressure of the battery. In this application, the battery is connected by a fixture, and a measuring hole is provided on the battery so that the air inlet of the pressure gauge connected to the fixture is connected to the inside of the battery, so that the pressure gauge can detect the internal pressure value of the battery during thermal runaway, thereby optimizing the pressure relief behavior of the battery during thermal runaway and improving the reliability of the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of battery testing, and in particular to a battery thermal runaway pressure measuring device and a battery thermal runaway pressure measuring method. Background Art

[0002] Lithium-ion batteries have the advantages of high energy density, high power density, and low self-discharge rate. As an ideal energy storage device, they are widely used in various power tools, electric vehicles, and various portable devices. However, when lithium-ion batteries are subjected to thermal, mechanical, and electrical abuse during use, a chain reaction of thermal decomposition of the chemical materials inside the battery will occur, leading to thermal runaway. During the chain reaction of thermal runaway, the battery generates gas, which increases the internal pressure of the battery until the safety valve ruptures and the gas is ejected. The internal pressure changes and pressure relief process of the battery during thermal runaway are of great significance to the abuse safety design of lithium-ion batteries. Existing methods for measuring the internal pressure of lithium-ion batteries cannot detect the internal pressure of the battery during thermal runaway, making it difficult to optimize the pressure relief behavior of the battery during thermal runaway. Therefore, it is of great significance to develop an internal pressure measurement device for the battery during thermal runaway. Summary of the Invention

[0003] Based on this, it is necessary to provide a battery thermal runaway pressure measurement device to address the technical problem that the existing technology cannot detect the internal pressure of lithium-ion batteries in the thermal runaway state, making it difficult to optimize the internal pressure changes and pressure relief process of the battery.

[0004] A battery thermal runaway pressure measuring device, comprising:

[0005] clamps for connecting batteries;

[0006] A pressure gauge, comprising a main body, a sensing head and an air inlet, wherein the sensing head is connected to an end of the main body, the sensing head is connected to the fixture, and the air inlet is located on an end surface of the sensing head;

[0007] The air inlet is used to communicate with a measuring hole opened on a side surface of the battery and connected to the interior of the battery, so as to measure the internal pressure of the battery.

[0008] In one embodiment, the measuring hole is provided on a first side surface of the battery;

[0009] Part of the end surface of the sensing head is used to press against the first side surface, and when the part of the end surface of the sensing head presses against the first side surface, the projected edge of the end surface of the sensing head on the first side surface is located outside the hole wall of the measuring hole.

[0010] In one embodiment, the fixture is provided with a mounting hole, the sensor head is passed through the mounting hole along a first direction, and is threadedly connected to the hole wall of the mounting hole so that the end face of the sensor head is pressed against the first side face of the battery.

[0011] In one embodiment, the clamp includes two mounting plates and at least two first fasteners, the two mounting plates are spaced apart along the first direction, and the two ends of the two mounting plates in the second direction are respectively connected by corresponding first fasteners to clamp the battery in the first direction, and the mounting hole is provided on one of the mounting plates, wherein the second direction is perpendicular to the first direction.

[0012] In one embodiment, the clamp further includes two clamps and at least two second fasteners, the two clamps are spaced apart along the second direction, and the two ends of the two clamps in the first direction are respectively connected by corresponding second fasteners for clamping the battery in the second direction.

[0013] In one embodiment, the clamping plate is provided with limit grooves at both ends in the first direction, and the mounting plate is respectively passed through the corresponding limit grooves at both ends along the second direction. The first fastener is connected to one end of the two mounting plates extending out of the limit grooves, and the limit grooves are used to avoid the mounting plates and to limit the displacement of the mounting plates relative to the clamping plate along a third direction, wherein the third direction is perpendicular to the first direction and the second direction respectively.

[0014] In one embodiment, the second fasteners are connected to both sides of the limiting groove on the clamping plate along the third direction.

[0015] In one embodiment, the battery thermal runaway pressure measuring device further includes a heat insulation plate, which is arranged between the clamping plate and the battery, and is used for heat insulation.

[0016] In one embodiment, a clamping cavity is defined between the two clamping plates and the two mounting plates, and at least one side of the clamping cavity is open, and the opening is used to avoid the safety valve of the battery.

[0017] The present invention also provides a method for measuring battery thermal runaway pressure, which can solve at least one of the above technical problems.

[0018] A battery thermal runaway pressure measurement method is provided, which is detected by the battery thermal runaway pressure measurement device described above. The battery thermal runaway pressure measurement method comprises the following steps:

[0019] Mounting the manometer on the battery using the fixture, and ensuring that the air inlet on the manometer is in communication with the measuring hole on the battery;

[0020] The internal pressure of the battery in the thermal runaway state is measured by a pressure gauge.

[0021] Beneficial effects:

[0022] An embodiment of the present invention provides a battery thermal runaway pressure measurement device, comprising a fixture and a pressure gauge; the fixture is used to connect to the battery; the pressure gauge comprises a main body, a sensing head, and an air inlet, wherein the sensing head is connected to the end of the main body and the sensing head is connected to the fixture, and the air inlet is located on the end face of the sensing head; the air inlet is used to communicate with a measuring hole opened on one side of the battery and connected to the interior of the battery to measure the internal pressure of the battery. In this application, the battery is connected via a fixture, and a measuring hole is provided on the battery so that the air inlet of the pressure gauge connected to the fixture is connected to the interior of the battery, thereby enabling the pressure gauge to detect the internal pressure value of the battery during thermal runaway, thereby optimizing the pressure relief behavior of the battery during thermal runaway and improving the reliability of the battery.

[0023] The battery thermal runaway pressure measurement method provided in an embodiment of the present invention is detected using the aforementioned battery thermal runaway pressure measurement device. The method comprises the following steps: mounting the pressure gauge on the battery using the fixture, connecting the air inlet on the pressure gauge to a measurement hole on the battery; and measuring the internal pressure of the battery under thermal runaway conditions using the pressure gauge. This method can achieve at least one of the aforementioned technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a battery thermal runaway pressure measurement device provided by one embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a battery thermal runaway pressure measurement device provided by one embodiment of the present invention;

[0026] Figure 3 A schematic diagram illustrating the connection between a pressure gauge and a mounting plate in a battery thermal runaway pressure measurement device provided by one embodiment of the present invention;

[0027] Figure 4 A flow chart of a method for measuring battery thermal runaway pressure according to an embodiment of the present invention;

[0028] Figure 5 This is a process diagram of the battery thermal runaway pressure measurement device provided by one embodiment of the present invention in actual battery testing.

[0029] Figure Number:

[0030] 100-clamp; 120-first mounting plate; 121-mounting hole; 122-boss; 130-clamping plate; 131-limiting groove; 140-first fastener; 150-second fastener; 160-heat insulation board; 170-second mounting plate; 180-clamping cavity; 200-pressure gauge; 210-main body; 220-sensing head; 300-battery; 310-first side; 320-positive pole; 330-negative pole. DETAILED DESCRIPTION

[0031] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0034] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0035] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0036] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0037] See Figure 1 , Figure 1 A schematic diagram of a battery thermal runaway pressure measurement device according to an embodiment of the present invention. The device comprises a fixture 100 and a pressure gauge 200. The fixture 100 is used to connect to a battery 300. The pressure gauge 200 comprises a main body 210, a sensing head 220, and an air inlet. The sensing head 220 is connected to an end of the main body 210 and to the fixture 100. The air inlet is located on the end face of the sensing head 220. The air inlet is connected to a measuring hole on a side of the battery 300 that connects to the interior of the battery 300, thereby measuring the internal pressure of the battery 300.

[0038] Specifically, in the present application, the battery 300 is connected by a clamp 100, and a measuring hole is provided on the battery 300 so that the air inlet of the pressure gauge 200 connected to the clamp 100 is connected to the interior of the battery 300, so that the pressure gauge 200 can detect the internal pressure value of the battery 300 during thermal runaway, and then optimize the pressure relief behavior of the battery during thermal runaway, thereby improving the reliability of the battery 300.

[0039] Among them, the pressure gauge 200 is a gas pressure sensor, which has an air intake pipe and a vacuum tube inside. The air intake pipe has an air inlet. When the battery 300 is in thermal runaway, gas will be generated inside the battery 300. The generated gas will enter the interior of the sensor through the measuring hole and the air inlet, thereby generating pressure on the vacuum tube. The pressure will increase with the increasing amount of gas entering. A varistor is installed on the other side of the vacuum tube. The varistor is a variable resistor that can continuously change the resistance size based on the pressure size. The change in resistance size can affect the current size in the circuit, thereby sending different electrical signals, and then the pressure value inside the battery 300 can be obtained.

[0040] See Figure 1 、 Figure 2 and Figure 3 , Figure 2 A schematic diagram of a battery thermal runaway pressure measurement device provided by one embodiment of the present invention; Figure 3 A schematic diagram illustrating the connection between the pressure gauge and the mounting plate in a battery thermal runaway pressure measurement device according to one embodiment of the present invention. In one embodiment, a measurement hole is provided on the first side surface 310 of the battery 300. A portion of the end surface of the sensing head 220 is adapted to abut against the first side surface 310. When the portion of the end surface of the sensing head 220 abuts against the first side surface 310, the projected edge of the end surface of the sensing head 220 on the first side surface 310 lies outside the wall of the measurement hole.

[0041] Specifically, the air inlet on the end face of the sensing head 220 opposes the measurement hole on the first side face 310 of the battery 300. When the end face of the sensing head 220 abuts the first side face 310 of the battery 300, the connection between the end face of the sensing head 220 and the first side face 310 is sealed, while the air inlet and the measurement hole are in communication. This allows the gas generated during thermal runaway of the battery 300 to directly enter the air inlet through the measurement hole and, subsequently, into the interior of the manometer 200. Compared to methods that employ other connecting components between the measurement hole and the air inlet, this shortens the time it takes for the gas to enter the interior of the manometer 200, improving the efficiency of pressure measurement. Furthermore, the gas generated during thermal runaway of the battery 300 is completely located within the battery 300, eliminating any interference with the air pressure caused by other connecting components, thereby improving the accuracy of the pressure measurement within the battery 300. It should be noted that the diameter of the measurement hole is 3 mm to 5 mm.

[0042] In addition, when the battery 300 is in a thermal runaway process, the pressure inside the battery 300 gradually increases, and the outer wall of the battery 300 will undergo a certain deformation under the action of pressure. The end face of the sensing head 220 is pressed against the first side surface 310, which can limit the deformation of the outer wall of the battery 300 near the measuring hole of the battery 300 to a certain extent, so that the end face of the sensing head 220 and the outer wall of the battery 300 remain sealed. Compared with the measurement method in which the sensing head 220 extends into the measuring hole, in the present application, even if the hole wall of the measuring hole is deformed during the thermal runaway of the battery 300, since the projected edge of the end face of the sensing head 220 on the first side face 310 is located on the outside of the hole wall of the measuring hole, the air inlet and the measuring hole are always connected, and the end face of the sensing head 220 is sealed with the first side face 310 of the battery 300, it is possible to ensure accurate measurement of the internal pressure of the battery 300 during thermal runaway. In the measurement method in which the sensing head 220 extends into the measuring hole, once the hole wall of the measuring hole is deformed during the thermal runaway of the battery 300, the sensing head 220 and the hole wall of the measuring hole cannot be sealed and connected.

[0043] See Figure 1 and Figure 3 In one embodiment, a mounting hole 121 is provided on the fixture 100, and the sensor head 220 is passed through the mounting hole 121 along a first direction and is threadedly connected to the hole wall of the mounting hole 121 so that the end face of the sensor head 220 is tightly pressed against the first side surface 310 of the battery 300.

[0044] Specifically, the outer circumference of the sensor head 220 is threadedly connected to the wall of the mounting hole 121, thereby stably connecting the manometer 200 to the fixture 100 and allowing the end face of the sensor head 220 to stably abut the first side surface 310 of the battery 300. The sensor head 220 can be rotated to move closer to the first side surface 310 of the battery 300 in a first direction, thereby achieving a tighter abutment between the end face of the sensor head 220 and the first side surface 310 of the battery 300. This improves the sealing between the first side surface 310 of the battery 300 and the end face of the sensor head 220, thereby increasing the accuracy of the internal pressure measurement of the battery 300. Furthermore, the threaded connection between the manometer 200 and the fixture 100 allows for convenient disassembly of the manometer 200, thereby facilitating replacement of the manometer 200.

[0045] See Figure 1 and Figure 2 In one embodiment, the clamp 100 includes two mounting plates and at least two first fasteners 140, the two mounting plates are spaced apart along the first direction, and the two ends of the two mounting plates in the second direction are connected by corresponding first fasteners 140 respectively, so as to be used to clamp the battery 300 in the first direction, and the mounting hole 121 is provided on one of the mounting plates, wherein the second direction is perpendicular to the first direction.

[0046] Specifically, for ease of description, the mounting plate with mounting holes 121 is defined as the first mounting plate 120, and the other is defined as the second mounting plate 170. The first mounting plate 120 and the second mounting plate 170 are respectively attached to the two side surfaces of the battery 300 along the first direction. The first fasteners 140 clamp the two side surfaces of the battery 300 along the first direction, thereby fixing the relative position between the battery 300 and the fixture 100. The sensor head 220 is then threadedly connected to the first mounting plate 120, thereby fixing the relative position of the pressure sensor 200 and the fixture 100. Because the relative positions of the battery 300 and the fixture 100 are fixed, the relative positions of the manometer 200 and the fixture 100 are also fixed, thus ensuring a relative fixation between the manometer 200 and the battery 300. This, in turn, ensures a fixed relative position between the air inlet on the manometer 200 and the measurement hole on the first side 310 of the battery 300. This improves the stability of the electrical connection between the air inlet and the measurement hole during thermal runaway of the battery 300, thereby increasing the accuracy of the internal pressure measurement of the battery 300 during thermal runaway. Furthermore, by clamping the two side surfaces of the battery 300 along the first direction using the first mounting plate 120 and the second mounting plate 170, deformation of the first side 310 of the battery 300 is reduced, thereby improving the sealing performance at the connection between the end surface of the sensing head 220 and the first side 310 of the battery 300. In this embodiment, the first direction is the length of the battery 300, and the second direction is the width of the battery 300. In other embodiments, the first direction may also be the width of the battery 300, and the second direction may be the length of the battery 300.

[0047] It should be noted that the battery 300 in this embodiment is a hexahedral square lithium battery 300. In other embodiments, the battery 300 can also be of other types or other shapes, as long as the first mounting plate 120 and the second mounting plate 170 can respectively clamp the two side surfaces of the battery 300 along the first direction.

[0048] Furthermore, a portion of the first mounting plate 120 facing the battery 300 is provided with a boss 122. The boss 122 is used to abut the side wall of the battery 300. Therefore, under the action of the first fastener 140, the first mounting plate 120 can reduce deformation, so that the first mounting plate 120 and the side wall of the battery 300 are closely fitted, thereby reducing deformation of the first side surface 310 of the battery 300. Preferably, a portion of the second mounting plate 170 facing the battery 300 is also provided with a boss 122.

[0049] Furthermore, at least two first fasteners 140 fasten the first mounting plate 120 and the second mounting plate 170 with the same torque, thereby ensuring uniform force on both sides of the battery 300 along the first direction, thereby reducing deformation of the two sides of the battery 300 along the first direction. To ensure that the first mounting plate 120 and the second mounting plate 170 effectively clamp the battery 300, the clamping torque is greater than 1 Nm.

[0050] Furthermore, a gap is provided between the first fastener 140 and the sidewall of the battery 300, thereby leaving a margin to accommodate batteries 300 of different sizes, thereby improving the adaptability of the battery thermal runaway pressure measurement device. Preferably, the first fastener 140 is a bolt.

[0051] See Figure 1 and Figure 3 In one embodiment, a sealing portion is provided on the first mounting plate 120 , and the sealing portion is used to seal the connection between the end surface of the sensing head 220 and the first side surface 310 of the battery 300 .

[0052] Specifically, to ensure the seal between the end face of the sensing head 220 and the first side face 310 of the battery 300, the sealing portion may be a sealing ring, a sealant, or other materials, as long as they can achieve a seal between the end face of the sensing head 220 and the first side face 310 of the battery 300. Preferably, the sealing portion is resistant to high temperatures.

[0053] See Figure 1 and Figure 2 In one embodiment, the clamp 100 further includes two clamps 130 and at least two second fasteners 150, the two clamps 130 are spaced apart along the second direction, and the two ends of the two clamps 130 in the first direction are respectively connected by corresponding second fasteners 150 for clamping the battery 300 in the second direction.

[0054] Specifically, the two clamping plates 130 respectively adhere to the two side surfaces of the battery 300 along the second direction, and the second fasteners 150 clamp the two side surfaces of the battery 300 along the second direction, thereby reducing the deformation of the two side walls of the battery 300 along the second direction when the battery 300 experiences thermal runaway. Preferably, the clamping plates 130 are made of a high-density metal material to prevent the overall instability of the battery 300 during thermal runaway and improve the stability of the connection between the battery 300 and the clamp 100.

[0055] When the battery 300 is working, generally multiple batteries 300 are arranged in sequence along the width direction of the battery 300 and installed in the battery 300 installation groove. When the battery 300 has thermal runaway, the outer wall of the battery 300 will undergo a certain degree of deformation, such as bulging, so that the side wall of the battery 300 will be squeezed by the side wall of the adjacent battery 300 and pressed by the side wall of the battery 300 installation groove. The two clamping plates 130 respectively clamp the two side surfaces of the battery 300 along the second direction, and the first mounting plate 120 and the second mounting plate 170 respectively clamp the two side surfaces of the battery 300 along the first direction. This setting can accurately simulate the state of the battery 300 when thermal runaway occurs during operation, thereby improving the accuracy of the pressure gauge 200 in measuring the internal pressure of the battery 300 when the battery 300 has thermal runaway.

[0056] Furthermore, at least two second fasteners 150 tighten the two clamping plates 130 with the same torque, thereby ensuring uniform force on both sides of the battery 300 along the second direction, thereby reducing deformation of the two sides of the battery 300 along the second direction. To ensure the clamping effect of the two clamping plates 130 on the battery 300, the clamping torque is greater than 1 Nm. Preferably, the torque used by the second fasteners 150 to tighten the two clamping plates 130 is equal to the torque used by the first fasteners 140 to tighten the two mounting plates.

[0057] Furthermore, a gap is provided between the second fastener 150 and the sidewall of the battery 300, thereby leaving a margin to accommodate batteries 300 of different sizes, thereby improving the adaptability of the battery thermal runaway pressure measurement device. Preferably, the second fastener 150 is a bolt.

[0058] See Figure 1 In one embodiment, the clamping plate 130 is provided with limiting grooves 131 at both ends in the first direction, and the mounting plates are respectively provided with corresponding limiting grooves 131 at both ends along the second direction. The first fasteners 140 are connected to one end of the two mounting plates extending out of the limiting grooves 131. The limiting grooves 131 are used to avoid the mounting plates and to limit the displacement of the mounting plates relative to the clamping plate 130 along the third direction, wherein the third direction is perpendicular to the first direction and the second direction respectively.

[0059] Specifically, both ends of the clamping plate 130 in the first direction extend relative to the battery 300. A limiting groove 131 is provided at the end of the clamping plate 130 extending from the battery 300. The limiting groove 131 has an opening facing the first direction. The mounting plate extends into the limiting groove 131 through the opening and abuts against the two side walls of the limiting groove 131 in the third direction, thereby limiting the movement of the mounting plate in the third direction and improving the stability of the connection between the mounting plate and the battery 300. The provision of the opening facilitates the installation of the mounting plate and the clamping plate 130, thereby increasing the installation speed of the clamp 100.

[0060] Furthermore, the bottom wall of the limiting groove 131 on the side opposite to the opening is flush with the side wall of the battery 300, so that when the mounting plate is in contact with the side wall of the battery 300, the mounting plate abuts against the bottom wall of the limiting groove 131, thereby clamping the splint 130 on both sides along the first direction, that is, limiting the movement of the splint 130 along the first direction, thereby improving the stability of the connection between the splint 130 and the battery 300.

[0061] Furthermore, the two sides of the splint 130 in the third direction are flush with the two outer walls of the battery 300 in the height direction, the measuring hole is arranged in the middle of the first side 310 of the battery 300, the limiting groove 131 is arranged in the middle of the splint 130 in the third direction, and the mounting hole 121 is also arranged in the middle of the first mounting plate 120. Therefore, when installing the clamp 100, it is only necessary to align at least one side of the splint 130 along the third direction with one side wall of the battery 300 in the height direction to achieve accurate installation of the clamp 100, thereby enabling the air inlet on the pressure gauge 200 to be aligned with the measuring hole, thereby improving the measurement efficiency of the battery thermal runaway pressure measuring device.

[0062] See Figure 1 In one embodiment, second fasteners 150 are connected to both sides of the limiting groove 131 of the clamping plate 130 along the third direction.

[0063] Specifically, there are four second fasteners 150 , and two second fasteners 150 are symmetrically arranged on both sides of the limiting groove 131 , thereby improving the stability of the connection between the clamping plate 130 and the battery 300 .

[0064] Furthermore, the number of the first fasteners 140 is four, and the two ends of the two mounting plates in the second direction are respectively connected to two first fasteners 140 spaced apart along the third direction, thereby further improving the stability of the relative position between the battery 300 and the clamp 100.

[0065] See Figure 1 and Figure 2 In one embodiment, the battery thermal runaway pressure measuring device further includes a heat insulation plate 160 , which is arranged between the clamping plate 130 and the battery 300 , and is used for heat insulation.

[0066] Specifically, the contact area between the splint 130 and the side wall of the battery 300 is relatively large, and the provision of the heat insulating plate 160 can isolate the splint 130 from the battery 300. Therefore, when the battery 300 thermally runs away, the heat absorption by the splint 130 can be reduced, and the temperature uniformity of each side wall of the battery 300 can be improved, thereby reducing the deformation of the side wall of the battery 300 in the case of thermal runaway, and improving the accuracy of the pressure gauge 200 in measuring the internal pressure of the battery 300. It should be noted that in this embodiment, a heating plate is provided between the heat insulating plate 160 and the battery 300 to trigger the thermal runaway of the battery 300. During this process, the heat insulating plate 160 can play a heat insulating role and reduce the heat absorption by the splint 130. In other embodiments, thermal runaway of the battery 300 can also be achieved by overcharging or acupuncture.

[0067] In other embodiments, a heat insulation plate 160 is also provided between the mounting plate and the side wall of the battery 300 .

[0068] See Figure 1 and Figure 2 In one embodiment, a clamping cavity 180 is defined between the two clamping plates 130 and the two mounting plates, and at least one side of the clamping cavity 180 is open, and the opening is used to avoid the safety valve of the battery 300.

[0069] Specifically, the safety valve is arranged on one side of the battery 300 along the height direction and is located between the positive electrode column 320 and the negative electrode column 330 of the battery 300. Both sides of the clamping cavity 180 along the third direction are open, that is, both sides of the battery 300 along the third direction are in an exposed state, so that the safety valve can be avoided, so that when the battery 300 is in a thermal runaway state, after the internal pressure of the battery 300 reaches the valve opening pressure, the safety valve can open and release the pressure, thereby avoiding the explosion of the battery 300 and causing a safety accident.

[0070] See Figure 1 、 Figure 3 and Figure 4 , Figure 4 This is a flow chart of a battery thermal runaway pressure measurement method provided by one embodiment of the present invention. The battery thermal runaway pressure measurement method provided by one embodiment of the present invention is detected by the above-mentioned battery thermal runaway pressure measurement device. The battery thermal runaway pressure measurement method includes the following steps:

[0071] S10: The manometer 200 is mounted on the battery 300 by the fixture 100, and the air inlet on the manometer 200 is connected to the measuring hole opened on the battery 300;

[0072] S20 measures the internal pressure of the battery 300 in the thermal runaway state through the pressure gauge 200 .

[0073] Specifically, the battery 300 is connected through the fixture 100, and the pressure gauge 200 is connected to the fixture 100, so that the air inlet of the pressure gauge 200 connected to the fixture 100 is connected to the measuring hole of the battery 300 and the interior of the battery 300, so that the pressure gauge 200 can detect the internal pressure value of the battery 300 during thermal runaway, and then optimize the pressure relief behavior of the battery during thermal runaway, thereby improving the reliability of the battery 300.

[0074] See Figure 5 , Figure 5 This is a process diagram of the battery thermal runaway pressure measuring device provided by one embodiment of the present invention in actual battery testing. In this application, when the battery thermal runaway pressure measuring device is used to measure the thermal runaway of a shell-shaped lithium-ion battery 300, the battery 300 is first charged to full power, a hole is opened in the middle of the first side 310 of the battery 300, and then the side wall of the battery 300 is clamped using a clamp 100, and the pressure gauge 200 is installed on the first mounting plate 120. The thermal runaway of the battery 300 is triggered by the lateral heating method. Figure 5 As can be seen in the middle graph, before 1000 seconds into the experiment, the internal pressure and temperature of battery 300 gradually increased. After reaching the valve-opening pressure, the valve of battery 300 opened, causing a burst of fluid. Subsequently, the internal pressure of battery 300 decreased, and the pressure subsequently decreased. Over time, at the moment of thermal runaway, the pressure and temperature of battery 300 increased dramatically due to the violent runaway reaction. The pressure then rapidly decreased, and the temperature gradually decreased. This demonstrates that the present invention can accurately measure the internal pressure of a square-shell lithium-ion battery 300 during thermal runaway in real time.

[0075] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A battery thermal runaway pressure measurement device, characterized in that: include: clamps for connecting batteries; A pressure gauge, comprising a main body, a sensing head and an air inlet, wherein the sensing head is connected to an end of the main body, the sensing head is connected to the fixture, and the air inlet is located on an end surface of the sensing head; The air inlet is used to communicate with a measuring hole opened on a side surface of the battery and connected to the interior of the battery, so as to measure the internal pressure of the battery; The measuring hole is provided on the first side surface of the battery; The air inlet on the end surface of the sensing head is opposite to the measuring hole on the first side surface of the battery, a portion of the end surface of the sensing head is used to abut against the first side surface, and the connection between the end surface of the sensing head and the first side surface is sealed; When a portion of the end surface of the sensing head is pressed against the first side surface, a projected edge of the end surface of the sensing head on the first side surface is located outside the hole wall of the measuring hole.

2. The battery thermal runaway pressure measuring device according to claim 1, characterized in that: The fixture is provided with a mounting hole, the sensor head is passed through the mounting hole along a first direction and is threadedly connected to the hole wall of the mounting hole so that the end surface of the sensor head is tightly pressed against the first side surface of the battery.

3. The battery thermal runaway pressure measuring device according to claim 2, characterized in that: The clamp includes two mounting plates and at least two first fasteners, the two mounting plates are spaced apart along the first direction, and the two ends of the two mounting plates in the second direction are respectively connected by corresponding first fasteners to clamp the battery in the first direction, and the mounting hole is provided on one of the mounting plates, wherein the second direction is perpendicular to the first direction.

4. The battery thermal runaway pressure measuring device according to claim 3, characterized in that: The clamp further includes two clamping plates and at least two second fasteners, the two clamping plates are spaced apart along the second direction, and the two ends of the two clamping plates in the first direction are respectively connected by corresponding second fasteners for clamping the battery in the second direction.

5. The battery thermal runaway pressure measuring device according to claim 4, characterized in that: The clamping plate is provided with limit grooves at both ends in the first direction, and the mounting plate is respectively passed through the corresponding limit grooves at both ends along the second direction. The first fastener is connected to one end of the two mounting plates extending out of the limit grooves, and the limit grooves are used to avoid the mounting plates and to limit the displacement of the mounting plates relative to the clamping plate along a third direction, wherein the third direction is perpendicular to the first direction and the second direction respectively.

6. The battery thermal runaway pressure measuring device according to claim 5, characterized in that: The second fasteners are connected to the clamping plate at both sides of the limiting groove along the third direction.

7. The battery thermal runaway pressure measuring device according to claim 5, characterized in that: The battery thermal runaway pressure measuring device further includes a heat insulation plate, which is used to be arranged between the clamping plate and the battery, and is used for heat insulation.

8. The battery thermal runaway pressure measuring device according to any one of claims 4 to 7, characterized in that: A clamping cavity is formed between the two clamping plates and the two mounting plates. At least one side of the clamping cavity is open, and the open cavity is used to avoid the safety valve of the battery.

9. A method for measuring battery thermal runaway pressure, characterized in that: Detection is performed using the battery thermal runaway pressure measuring device according to any one of claims 1 to 8, wherein the battery thermal runaway pressure measuring method comprises the following steps: Mounting the manometer on the battery using the fixture, and ensuring that the air inlet on the manometer is in communication with the measuring hole on the battery; The internal pressure of the battery in the thermal runaway state is measured by a pressure gauge.

Images