A battery test fixture

Abstract

The application discloses a battery test tool, which comprises a pressure sensor, a heat insulation assembly, and a first heat insulation part and a second heat insulation part which jointly wrap the pressure sensor to realize heat insulation. In the sensing direction of the pressure sensor, the first heat insulation part and the second heat insulation part are opposite to each other with a reserved gap formed therebetween. The first heat insulation part and the second heat insulation part are respectively in profiled cooperation with the upper and lower functional surfaces of the pressure sensor which are perpendicular to the sensing direction, so as to solve the technical problem of how to ensure the working stability of the pressure sensor under the condition of battery thermal runaway experiment.

Description

Technical Field

[0001] This application relates to the field of battery testing technology, and in particular to a battery testing fixture. Background Technology

[0002] Thermal runaway, a typical failure mode, can cause batteries to expand violently, erupt, catch fire, or even explode, posing a serious threat to system safety and personnel safety. Therefore, in battery safety testing, the expansion force test of batteries under thermal runaway conditions has become an important part of evaluating battery safety performance.

[0003] In existing technologies, pressure sensors are typically used to collect the expansion force generated by a battery during thermal runaway in real time. However, due to the rapid increase in internal battery temperature during thermal runaway, heat transferred to the outside of the battery also accumulates rapidly, causing a significant rise in the surface temperature of the pressure sensor in the test fixture. When the operating temperature of the pressure sensor exceeds its tolerance limit, signal drift, data distortion, or even complete acquisition failure can easily occur, resulting in incomplete or inaccurate test data. This not only affects the reliability of the test results but may also prevent researchers from fully understanding the actual expansion force changes during battery thermal runaway, thus hindering the development of subsequent safety protection designs.

[0004] Therefore, ensuring the stability of pressure sensors in high-temperature environments under battery thermal runaway experimental conditions has become an urgent technical problem to be solved. Utility Model Content

[0005] One objective of this application is to provide a battery testing fixture that addresses the technical problem of ensuring the operational stability of a pressure sensor under battery thermal runaway experimental conditions.

[0006] To achieve the above objectives, this application provides a solution as follows: a battery testing fixture, which includes a pressure sensor; a heat insulation component, the heat insulation component including a first heat insulation part and a second heat insulation part that jointly wrap around the pressure sensor to achieve heat insulation; in the sensing direction of the pressure sensor, the first heat insulation part and the second heat insulation part are directly opposite each other and a reserved gap is formed between them; the first heat insulation part and the second heat insulation part respectively conform to the upper and lower functional surfaces of the pressure sensor perpendicular to the sensing direction.

[0007] Optionally, the first heat insulation part is disposed between the pressure sensor and the battery under test, and is in contact with the upper functional surface of the pressure sensor. The second heat insulation part includes a load-bearing part parallel to the first heat insulation part and a side edge extending vertically from the edge of the load-bearing part. The load-bearing part covers the lower functional surface of the pressure sensor, and the side edge covers the side surface of the pressure sensor. A reserved gap is formed between the first heat insulation part and the side edge.

[0008] Optionally, the battery testing fixture also includes a flexible heat insulation layer, which is disposed between the side edge and the pressure sensor. The flexible heat insulation extends from the junction of the load-bearing part and the side edge to the edge of the side edge, and the extended end is flush with the edge of the side edge.

[0009] Optionally, the thickness of the flexible insulation layer is 0.4 to 0.8 times the thickness of the side portion.

[0010] Optionally, a relief groove is provided on the side of the first heat insulation part near the second heat insulation part, a pre-reserved gap is maintained between the bottom of the relief groove and the side edge, and the side edge is inserted into the relief groove.

[0011] Optionally, the depth of the side edge inserted into the relief groove is 0.2 to 0.4 times the depth of the relief groove.

[0012] Optionally, the width of the clearance groove is 1.2 to 1.4 times the thickness of the side edge.

[0013] Optionally, the ratio of the depth of the relief groove to the thickness of the first heat insulation part ranges from 0.3 to 0.6.

[0014] Optionally, the width of the reserved gap can range from 1 to 10 millimeters.

[0015] Optionally, the battery testing fixture also includes a friction anti-slip layer, which is disposed on the first heat insulation part and located between the first heat insulation part and the pressure sensor.

[0016] The beneficial effects of this application are as follows: To address the problem in existing technologies where pressure sensors are prone to failure due to high temperatures during battery thermal runaway experiments, thus failing to accurately reflect battery expansion force, this application provides a battery testing fixture. A heat insulation component, including a first heat insulation part and a second heat insulation part, is arranged around the pressure sensor. These components are fitted tightly to the sensor's functional surface using a conformal fitting method, forming a wraparound heat insulation protective layer. This significantly reduces the heat transfer rate, extends the sensor's stable operating time under extreme experimental conditions, and improves the accuracy and reliability of expansion force acquisition. Simultaneously, a pre-reserved gap is formed between the two components in the sensing direction of the pressure sensor to prevent the supporting force of the heat insulation component's own structure from interfering with the test results. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1This is a schematic diagram of the structure of a battery testing fixture provided in an embodiment of this application; Figure 2 This is a schematic diagram of another battery testing fixture provided in an embodiment of this application; Figure 3 This is provided by the embodiments of this application. Figure 2 A magnified view of a portion of region A in the middle.

[0019] Explanation of icon numbers: 10. Pressure sensor; 20. Thermal insulation component; 21. First thermal insulation part; 211. Relief groove; 22. Second thermal insulation part; 221. Load-bearing part; 222. Side edge part; 30. Reserved gap; 40. Flexible thermal insulation layer; 50. Friction anti-slip layer. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0022] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0023] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of a battery testing fixture provided in an embodiment of this application. Figure 1 In the diagram, h1 represents the thickness of the side edge 222, h2 represents the thickness of the flexible insulation layer 40, h3 represents the thickness of the first insulation part 21, and d represents the width of the reserved gap 30.

[0024] This application provides a battery testing fixture to ensure the stable operation of a pressure sensor 10 under battery thermal runaway experimental conditions, thereby ensuring accurate acquisition of battery expansion force. The battery testing fixture includes a pressure sensor 10 and a heat insulation component 20 disposed outside the pressure sensor 10. By arranging the heat insulation component 20 around the pressure sensor 10, this application can effectively isolate the direct effect of the high-temperature environment generated during thermal runaway on the sensor, thereby extending the stable operating time of the pressure sensor 10 under extreme experimental conditions.

[0025] The heat insulation component 20 includes a first heat insulation part 21 and a second heat insulation part 22. These two parts are positioned opposite each other and together enclose the pressure sensor 10, thus forming a heat-insulating protective layer around the sensor. In the sensing direction of the pressure sensor 10, the first heat insulation part 21 and the second heat insulation part 22 are located on opposite sides of the pressure sensor 10, facing each other and spaced apart, thus forming a reserved gap 30 between them. This reserved gap 30 ensures that the pressure sensor 10 can normally sense and transmit the expansion force of the battery during thermal runaway, and also prevents the structural support of the heat insulation component 20 itself from directly interfering with the test results.

[0026] Furthermore, the first heat insulation part 21 and the second heat insulation part 22 are respectively conformally fitted to the upper and lower functional surfaces of the pressure sensor 10. Both the upper and lower functional surfaces are perpendicular to the sensing direction. By adopting a conformal fitting method, the heat insulation component 20 can be tightly fitted to the pressure sensor 10, reducing the heat transfer path caused by structural gaps, thereby improving the overall heat insulation performance. At the same time, the conformal design can also ensure that the heat insulation component 20 maintains a stable assembly state in high-temperature environments, avoiding the impact of deformation or loosening on test accuracy.

[0027] In terms of material selection, the thermal insulation component 20 can preferably be made of materials with low thermal conductivity and good high-temperature resistance, such as ceramic fiber, aerogel, or high-temperature resistant composite thermal insulation materials. These materials, while ensuring strength, possess excellent thermal insulation capabilities, which can significantly slow down the conduction speed of external high temperatures to the sensor, thereby keeping the sensor within a reasonable temperature range throughout the experiment and ensuring the reliability of its data acquisition.

[0028] In one implementation method, in some optimized embodiments, the first heat insulation part 21 is preferably disposed between the pressure sensor 10 and the battery under test, and is in contact with the upper functional surface of the pressure sensor 10. This can directly block high-temperature heat radiation and heat conduction from the direction of the battery in the thermal runaway experiment, without changing the force transmission path of the sensor in the sensing direction, thereby ensuring that the expansion force can actually act on the pressure sensor 10.

[0029] The second heat insulation part 22 adopts a composite structure, including a load-bearing part 221 and a side edge part 222. The load-bearing part 221 is arranged parallel to the first heat insulation part 21 and covers the lower functional surface of the pressure sensor 10. The side edge part 222, which is connected to the load-bearing part 221, extends vertically from the edge of the load-bearing part 221 and fits against the side of the pressure sensor 10, so that the circumferential outer wall of the pressure sensor 10 can be covered and protected.

[0030] A reserved gap 30 is formed between the first heat insulation part 21 and the side edge part 222. This reserved gap 30 also prevents the heat insulation part from exerting additional mechanical force on the sensor due to thermal expansion during the experiment, thus ensuring the stability and reliability of the test data.

[0031] In some optimized embodiments, the battery testing fixture may further include a flexible heat insulation layer 40. The flexible heat insulation layer 40 is disposed between the side edge 222 and the pressure sensor 10, serving to buffer, conform, and further insulate. By introducing a flexible material layer between the rigid heat insulation structure and the outer surface of the pressure sensor 10, stress concentration caused by assembly tolerances, temperature changes, or uneven force can be effectively avoided, thereby reducing the risk of damage to the pressure sensor 10 during high-temperature testing.

[0032] The flexible thermal insulation layer 40 extends from the junction of the load-bearing portion 221 and the side edge portion 222, and extends along the inner surface of the side edge portion 222 to its edge. The extended end of the flexible thermal insulation layer 40 is flush with the edge of the side edge portion 222, thus ensuring that the entire sidewall of the pressure sensor 10 is covered, further improving the integrity and uniformity of thermal insulation. The presence of the flexible thermal insulation layer 40 can, on the one hand, absorb the thermal expansion differences caused by rapid temperature changes under thermal runaway conditions, reducing friction and stress transmission between the thermal insulation component and the pressure sensor 10; on the other hand, the flexible thermal insulation layer 40 itself has a certain degree of low thermal conductivity, which can further reduce the rate of external heat transfer to the sensor, achieving a dual thermal insulation protection effect.

[0033] The flexible insulation layer 40 can be made of high-temperature resistant silicone sheet, foam, ceramic fiber felt, or composite aerogel membrane, etc. It possesses good flexibility and heat resistance, and can automatically adapt to and fit minor irregularities on the outer wall of the sensor, improving the sealing and stability of the insulation. In some modified embodiments, the flexible insulation layer 40 can be designed as a detachable structure, for example, fixed to the inner surface of the side edge 222 by slots, nesting, or adhesive bonding, facilitating quick replacement after aging or wear of the flexible insulation layer 40.

[0034] Furthermore, in some optimized embodiments, the thickness of the flexible insulation layer 40 can be set to 0.4 to 0.8 times the thickness of the side edge 222. By limiting the thickness range, a good balance can be achieved between thermal insulation performance and structural stability.

[0035] On the one hand, when the thickness of the flexible insulation layer 40 is less than 0.4 times the thickness of the side edge 222, its insulation capacity is insufficient, making it difficult to effectively slow down the conduction speed of external high temperature to the pressure sensor 10. At the same time, its buffering effect under stress will also be significantly weakened, easily leading to premature failure of the insulation layer. On the other hand, when the thickness of the flexible insulation layer 40 exceeds 0.8 times the thickness of the side edge 222, although the insulation performance is enhanced, it will result in an excessively large overall structural volume. This not only increases the assembly space requirement but may also change the stress state between the sensor and the testing fixture, affecting the accuracy of expansion force transmission.

[0036] Within the thickness range defined in this embodiment, the flexible thermal insulation layer 40 maintains good flexibility and fit, providing a uniform and stable covering effect for the pressure sensor 10, while also playing an effective role in thermal insulation and buffering during the experiment. At the same time, this thickness design also takes into account material costs and processing technology, avoiding material waste due to excessively thick insulation layers or decreased reliability due to excessively thin layers.

[0037] Additionally, please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of another battery testing fixture provided in an embodiment of this application. Figure 3 This is provided by the embodiments of this application. Figure 2 A magnified view of a portion of region A in the middle. Figure 3 In the diagram, s1 represents the depth to which the side edge 222 is inserted into the relief groove 211, s2 represents the depth of the relief groove 211, and h4 represents the width of the relief groove 211. In some embodiments, the relief groove 211 may be provided on the side of the first heat insulation part 21 near the second heat insulation part 22. The relief groove 211 is used to accommodate a portion of the side edge 222, so that the side edge 222 can be inserted into the relief groove 211, and a certain reserved gap 30 is maintained between the bottom of the relief groove 211 and the side edge 222. In this embodiment, the originally exposed reserved gap 30 between the first heat insulation part 21 and the side edge 222 is transferred to the inside of the relief groove 211, thereby avoiding direct exposure of the pressure sensor 10 in a local area and improving the integrity and continuity of the overall heat insulation protection.

[0038] In this embodiment, the presence of the relief groove 211 allows the first heat insulation part 21 and the second heat insulation part 22 to form a nested connection, thereby further improving the assembly reliability between the heat insulation components 20 and reducing the risk of misalignment or loosening caused by thermal expansion and contraction during the experiment. Simultaneously, by hiding the reserved gap 30 inside the groove, the mechanical transmission in the sensing direction of the pressure sensor 10 can be maintained smoothly while reducing direct radiation and convection transfer of heat to the sensor through exposed surfaces, significantly improving the sensor's protection capability under extreme temperatures. In some modified embodiments, the inner wall of the relief groove 211 can be coated with a high-reflectivity, high-temperature resistant coating, such as a ceramic reflective coating or a metal oxide heat-insulating coating, thereby further blocking heat radiation while improving the durability of the heat insulation component 20.

[0039] Furthermore, in some optimized embodiments, the insertion depth of the side edge 222 into the relief groove 211 is preferably set to 0.2 to 0.4 times the groove depth of the relief groove 211. By limiting the insertion depth, it can be ensured that there is always a sufficient reserved gap 30 between the bottom of the relief groove 211 and the side edge 222, thereby achieving a good balance between structural stability and thermal insulation effect.

[0040] If the insertion depth is less than 0.2 times the depth of the relief groove 211, the fit between the side edge 222 and the relief groove 211 will be shallow. This can easily lead to loosening or displacement during high-temperature experiments due to stress or thermal expansion and contraction, thus reducing the stability of the connection between the insulation components 20 and negatively impacting the long-term reliability of the experiment. Conversely, if the insertion depth exceeds 0.4 times the groove depth, the reserved gap 30 will be too small, potentially causing rigid contact between the insulation component 20 and the pressure sensor 10. This could affect the actual transmission path of the expansion force and, in extreme cases, even cause additional interference to the sensor. Within the range of 0.2 to 0.4 times the groove depth, the side edge 222 can be stably embedded inside the relief groove 211, providing necessary limiting and guiding functions to prevent relative displacement between the insulation components while ensuring the sufficient existence of the reserved gap 30.

[0041] Based on this, in some optimized embodiments, the width of the relief groove 211 is preferably 1.2 to 1.4 times the thickness of the side edge 222. Under this constraint, the side edge 222 can be smoothly inserted into the relief groove 211 without excessive contact friction due to an overly close fit. Furthermore, a moderate width margin can also provide a certain installation tolerance during assembly, avoiding interference caused by component machining errors or assembly errors.

[0042] In the battery expansion force testing scenario described in this application, if there is an excessively tight frictional fit between the side edge 222 and the clearance groove 211, it will interfere with the pressure transmission during the battery expansion process, thereby affecting the accuracy and repeatability of the measurement data. By controlling the width to be between 1.2 and 1.4 times the thickness of the side edge 222, the adverse effects of friction on the overall system sensitivity can be effectively reduced, enabling the pressure sensor 10 to respond realistically and promptly to the load changes caused by battery expansion. At the same time, this width range will not excessively increase the size of the clearance groove 211, thereby ensuring that the side edge 222 can still maintain a stable support and guiding function after insertion, avoiding wobbling or displacement.

[0043] In some embodiments, the depth of the relief groove 211 can be set to 0.3 to 0.6 times the thickness of the first heat insulation part 21. By limiting this ratio range, the function of the relief groove 211 in accommodating the side edge 222 can be guaranteed while avoiding excessive weakening or damage to the overall structure of the first heat insulation part 21. If the depth of the relief groove 211 is too small, the reserved gap 30 will be too small; conversely, if the depth of the relief groove 211 is too large, it may weaken the load-bearing capacity of the first heat insulation part 21, making it prone to deformation or cracking during high-temperature expansion or experiments, thereby reducing the heat insulation performance and structural reliability.

[0044] In this embodiment, within a range of 0.3 to 0.6 times, the first heat insulation part 21 can maintain sufficient thickness and strength to withstand heat transfer during the experiment and mechanical forces generated during tooling assembly. At the same time, the positioning groove 211 can still provide a stable embedding space for the side edge part 222, thereby achieving a balance between heat insulation performance and mechanical reliability.

[0045] Furthermore, in some optimized embodiments, the width of the reserved gap 30 is preferably set to be between 1 and 10 mm. A reserved gap 30 that is too narrow will cause excessively tight contact between the thermal insulation component 20 and the pressure sensor 10, thereby applying additional mechanical pressure to the sensor under high-temperature conditions and affecting the accuracy of the expansion force measurement; while a gap that is too wide will weaken the thermal insulation capacity, making it easier for heat to be transferred to the pressure sensor 10 through air convection or radiation, reducing the thermal insulation protection performance. Within the range of 1 to 10 mm, the reserved gap 30 can ensure that the thermal insulation components 20 remain in a non-contact state while forming stable thermal insulation protection between the thermal insulation component 20 and the pressure sensor 10.

[0046] Additionally, in some optimized embodiments, the battery testing fixture may also include a friction anti-slip layer 50. This friction anti-slip layer 50 is disposed on the first heat insulation part 21, located between the first heat insulation part 21 and the pressure sensor 10, thereby forming an additional fixing layer between the heat insulation component 20 and the sensor. By introducing the friction anti-slip layer 50, the friction between the pressure sensor 10 and the heat insulation component can be effectively increased, preventing sensor displacement or slippage caused by assembly deviations, vibration, or thermal expansion during the experiment, thereby ensuring the stability and measurement accuracy of the sensor under high-temperature thermal runaway conditions.

[0047] The thickness and surface treatment of the friction anti-slip layer 50 can be optimized according to actual experimental requirements. For example, by adding micro-textures or micropores to the surface of the friction anti-slip layer 50, the friction and adhesion stability can be further improved, while the heat conduction path of the insulating air layer can be improved, thus synergistically enhancing the heat insulation and anti-slip effects. In some modified embodiments, the friction anti-slip layer 50 can be designed as a detachable or replaceable structure to facilitate maintenance, replacement, or adaptation to pressure sensors 10 of different specifications during long-term experimental use.

[0048] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0049] The above description is merely a preferred embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the content of this application's specification and drawings under the concept of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A battery testing fixture, characterized in that, include: Pressure sensor; A heat insulation component includes a first heat insulation part and a second heat insulation part that together wrap around the pressure sensor to achieve heat insulation; in the sensing direction of the pressure sensor, the first heat insulation part and the second heat insulation part are opposite each other and spaced apart, with a reserved gap between them; the first heat insulation part and the second heat insulation part respectively conform to the upper and lower functional surfaces of the pressure sensor perpendicular to the sensing direction.

2. The battery testing fixture according to claim 1, characterized in that, The first heat insulation part is disposed between the pressure sensor and the battery under test, and is in contact with the upper functional surface of the pressure sensor. The second heat insulation part includes a load-bearing part parallel to the first heat insulation part and a side edge extending vertically from the edge of the load-bearing part. The load-bearing part covers the lower functional surface of the pressure sensor, and the side edge covers the side surface of the pressure sensor. A reserved gap is formed between the first heat insulation part and the side edge.

3. The battery testing fixture according to claim 2, characterized in that, The battery testing fixture also includes a flexible heat insulation layer, which is disposed between the side edge and the pressure sensor. The flexible heat insulation layer extends from the junction of the load-bearing part and the side edge to the edge of the side edge, and the extended end is flush with the edge of the side edge.

4. The battery testing fixture according to claim 3, characterized in that, The thickness of the flexible insulation layer is 0.4 to 0.8 times the thickness of the side edge portion.

5. The battery testing fixture according to claim 2, characterized in that, The first heat insulation part has a relief groove on the side near the second heat insulation part. The bottom of the relief groove and the side edge part maintain the reserved gap, and the side edge part is inserted into the relief groove.

6. The battery testing fixture according to claim 5, characterized in that, The depth to which the side edge is inserted into the relief groove is 0.2 to 0.4 times the depth of the relief groove.

7. The battery testing fixture according to claim 5, characterized in that, The width of the clearance groove is 1.2 to 1.4 times the thickness of the side edge.

8. The battery testing fixture according to claim 5, characterized in that, The ratio of the depth of the relief groove to the thickness of the first heat insulation part ranges from 0.3 to 0.

6.

9. The battery testing fixture according to any one of claims 1 to 8, characterized in that, The width of the reserved gap ranges from 1 to 10 millimeters.

10. The battery testing fixture according to any one of claims 1 to 8, characterized in that, The battery testing fixture also includes a friction anti-slip layer, which is disposed on the first heat insulation part and located between the first heat insulation part and the pressure sensor.

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