A test device, test system, and needle stick test method for battery devices

Abstract

The application relates to the technical field of battery safety testing and fault diagnosis, in particular to a testing device, a testing system and a needle puncture testing method of a battery device. The testing device comprises a base, a supporting platform and a testing assembly. The testing assembly comprises a servo electric cylinder and a probe. The servo electric cylinder and the probe are connected through an insulating piece, which can reduce the risk of an external conductive loop formed by the electric core, the probe, the battery device shell and the servo electric cylinder, thereby reducing the risk of early ignition caused by the short circuit of the external conductive loop in the testing process, and the accuracy of the testing structure can be improved, so as to accurately evaluate the safety performance of the battery device.

Description

Technical Field

[0001] This application relates to the field of battery safety testing and fault diagnosis technology, and in particular to a testing device, a testing system, and a needle penetration test method for a battery device. Background Technology

[0002] According to the safety testing standards for power batteries, vehicle power batteries need to undergo a nail penetration test. This test involves inserting a probe into the battery pack at a preset speed. When the probe simultaneously pierces the positive and negative electrodes and the separator in between, it causes a large-area, low-resistance, severe short circuit. All the electrical energy stored in the cell is rapidly released as heat at the short circuit point, leading to a sharp rise in local temperature. This high temperature triggers the decomposition of the positive and negative electrode materials and electrolyte, releasing oxygen and flammable gases. Ultimately, this could lead to a thermal runaway chain reaction, causing combustion or explosion. The nail penetration test simulates the thermal runaway process caused by metal foreign objects piercing the battery pack in traffic accidents or by metal burrs caused by manufacturing defects, thus evaluating the battery pack's safety performance and resistance to thermal runaway.

[0003] The main purpose of the needle penetration test is to short-circuit the positive and negative electrodes with a probe. However, during the test, the battery device, the probe, and the metal structures of the test device, such as the motor and frame, can easily form an unexpected external conductive circuit. This short circuit introduced by the test device itself will cause a large current discharge and arcing before the internal short circuit of the battery cell, thus igniting the battery device in advance, interfering with the judgment of thermal runaway, distorting the test results, and making it impossible to accurately assess the safety performance of the battery device. Summary of the Invention

[0004] This application provides a testing device, a testing system, and a needle penetration test method for a battery device, which can reduce the risk of forming a conductive circuit outside the battery cell and improve the accuracy of test results.

[0005] The first aspect of this application provides a testing apparatus for performing a nail penetration test on a battery device. The testing apparatus includes a base, a support platform mounted on the base, and a testing component mounted on the base. The support platform supports the battery device, and the testing component is located on the side of the support platform away from the battery device along the height direction of the testing apparatus. The testing component includes a servo electric cylinder and a probe, which are connected by an insulating component. The servo electric cylinder can drive the probe to move towards or away from the battery device.

[0006] In this application, the servo electric cylinder and the probe are connected by an insulating component, which can reduce the risk of the battery cell, probe, battery device housing and servo electric cylinder being connected to form an external conductive circuit. This reduces the risk of premature ignition of the battery device caused by a short circuit in the external conductive circuit during the test, and can improve the accuracy of the test structure, so as to accurately evaluate the safety performance of the battery device.

[0007] In some possible designs, the probe includes a rod and an insertion end. Along the probe's axial direction, the insertion end is located at the end of the rod away from the servo-electric cylinder. Along the probe's axial direction and in the direction from the rod towards the insertion end, the cross-sectional area of ​​the insertion end gradually decreases. The outer surface of the rod is covered with a first insulating layer.

[0008] In some possible designs, the probe has a receiving groove in which a temperature sensor is disposed, and the temperature sensor is bonded and fixed to the probe; and / or, the probe also includes a connecting wire, one end of which is electrically connected to the insertion end, and the other end of which is used for electrical connection to the EIS analysis module.

[0009] In some possible designs, the test assembly also includes an insulating base, through which the servo electric cylinder is mounted to the base.

[0010] In some possible designs, the test apparatus also includes a rotation mechanism, through which the insulating base is mounted on the base, and the rotation mechanism is capable of driving the insulating base to rotate about a first direction and / or a second direction.

[0011] In some possible designs, the base includes a first rod extending along a first direction, a rotating mechanism mounted on the first rod, and when the testing device is in the debugging state, the rotating mechanism can move relative to the first rod along the first direction; when the testing device is in the testing state, the rotating mechanism and the first rod are locked and fixed by a first fastener. The base also includes a second rod extending along a second direction, with the first rod mounted on it. When the testing device is in the debugging state, the first rod can move relative to the second rod along the second direction; when the testing device is in the testing state, the first rod and the second rod are locked and fixed by a second fastener.

[0012] In some possible designs, the support platform includes a bracket mounted on a base, the bracket having a support surface for supporting the battery device, the support surface being covered with a second insulating layer.

[0013] In some possible designs, the support platform also includes a clamping member mounted on the bracket. The clamping member has a clamping portion along the height direction of the test device. The gap between the clamping portion and the support surface is used to accommodate the battery device. The clamping portion is used to abut against the battery device in the height direction of the test device. When the test device is in the commissioning state, the clamping member can move relative to the bracket along the height direction of the test device. When the test device is in the testing state, the clamping member and the bracket are locked and fixed by a third fastener.

[0014] In some possible designs, the servo electric cylinder is connected to the insulator via a pressure sensor.

[0015] In some possible designs, multiple test components are arranged along a first direction and / or a second direction.

[0016] A second aspect of this application provides a testing system, which includes the testing device described in any of the above claims, and further includes a controller connected to a servo electric cylinder of the testing device.

[0017] In this application, the servo electric cylinder and the probe are connected by an insulating component, which can reduce the risk of the battery cell, probe, battery device housing and servo electric cylinder being connected to form an external conductive circuit. This reduces the risk of premature ignition of the battery device caused by a short circuit in the external conductive circuit during the test, and can improve the accuracy of the test structure, so as to accurately evaluate the safety performance of the battery device.

[0018] The controller can be connected to the aforementioned servo electric cylinder and rotary mechanism. In other words, the controller can control the linkage of all the motors, electric cylinders, and pneumatic cylinders included in the test system. This can facilitate the improvement of the accuracy of the position, angle, force, and distance of the probe penetrating the battery device, thereby improving the accuracy and reliability of the test results.

[0019] In some possible designs, the test system also includes a data acquisition module and an observation module, with the observation module and controller connected to the data acquisition module respectively. The observation module is used to observe the battery device.

[0020] In some possible designs, the test system also includes a data acquisition module and a resistance strain gauge, with the strain gauge and controller connected to the data acquisition module respectively. The resistance strain gauge is used to conform to the surface of the battery device.

[0021] The third aspect of this application provides a needle penetration test method for a battery device, wherein the battery device is subjected to a needle penetration test using the test system described in any of the above claims. The needle penetration test method includes: placing the battery device on the support platform of the test device, controlling the test component to move to a preset position, controlling the probe to rotate to a preset angle, and driving the probe to penetrate the battery device via a servo electric cylinder.

[0022] In this application, the servo electric cylinder and the probe are connected by an insulating component, which can reduce the risk of the battery cell, probe, battery device housing and servo electric cylinder being connected to form an external conductive circuit. This reduces the risk of premature ignition of the battery device caused by a short circuit in the external conductive circuit during the test, and can improve the accuracy of the test structure, so as to accurately evaluate the safety performance of the battery device.

[0023] In some possible designs, during the process of the probe penetrating the battery device, the needle penetration test method includes: a temperature sensor synchronously collecting temperature information and transmitting the temperature information to a data acquisition module in real time, and the data acquisition module acquiring the resistance value of the resistance strain gauge in real time, the data acquisition module synchronously acquiring the voltage and current data of the battery device, the data acquisition module transmitting the temperature information, voltage data, current data and time information to a computer in real time, and the computer generating a multi-channel temperature-strain curve and a VI curve.

[0024] In some possible designs, the needle penetration test method includes: the computer extracts the time T1 corresponding to the temperature change from the temperature-strain curve, the computer extracts the start time T2 of the voltage and current change from the VI curve, the computer compares T1 and T2, if T1 is earlier than T2, the computer determines that the battery device was punctured by the probe first and then thermal runaway occurred, if T2 is earlier than T1, the computer determines that the battery device experienced an internal short circuit first and then thermal runaway occurred, and the computer generates a test report based on the judgment result.

[0025] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments 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 these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the test device in some embodiments; Figure 2 for Figure 1 A schematic diagram of the structure of the test component in some embodiments; Figure 3 for Figure 2 A schematic diagram of the probe in some embodiments; Figure 4 for Figure 3 Cross-sectional views of the rod in some embodiments; Figure 5 This is a schematic diagram of the connection structure between the first rod and the rotating mechanism in the first embodiment. Figure 6 A cross-sectional view of the connection structure between the first rod and the rotating mechanism in the second embodiment; Figure 7 A cross-sectional view of the connection structure between the first rod and the rotating mechanism in the third embodiment; Figure 8This is a top view of the testing apparatus in some embodiments; Figure 9 for Figure 1 A schematic diagram of the test device in the first direction; Figure 10 for Figure 1 The schematic diagram of the test device in the second direction.

[0028] Figure label: 100 - Base; 110 - Frame; 120 - First rod; 121 - First sliding member; 1211 - Free end; 122 - First fastener; 123 - Mounting hole; 130 - Second rod; 200 - Supporting platform; 210 - Bracket; 211 - Supporting surface; 220 - Clamping element; 221 - Clamping part; 300-Test component; 310-Probe; 311-Rod; 312-Insertion end; 313-Receiving groove; 320-Insulator; 330-Insulating base; 400-Rotation mechanism. Detailed Implementation

[0029] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0030] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0031] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0032] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0033] The first aspect of this application provides a testing apparatus for performing a nail penetration test on a battery device. The battery device can be a battery module, which includes a module housing and multiple battery packs installed within the module housing. Multiple battery cells are disposed within each battery pack. The battery device can also be a battery pack, or it can be a battery cell. This application does not specifically limit the subject of the test; for ease of description, the following description will refer to the battery device as a battery module.

[0034] Figure 1 This is a schematic diagram of the testing device in some embodiments. For example... Figure 1 As shown, the testing device includes a base 100, a support platform 200 mounted on the base 100, and a testing component 300 mounted on the base 100. The support platform 200 supports the battery device. Along the height direction Z of the testing device, the testing component 300 is located on the side of the support platform 200 away from the battery device. That is, if the battery device is placed on the upper part of the support platform 200, the testing component 300 is located on the lower side of the support platform 200. The support platform 200 has a window, through which the probe 310 of the testing component 300 can pass through the support platform 200 to pierce the battery device. The testing device provided in this application embodiment can simulate the process of thermal runaway caused by a foreign object piercing the bottom of the battery device.

[0035] Figure 2 for Figure 1 The test component 300 is shown in a structural diagram in some embodiments. For example... Figure 2 As shown, the test assembly 300 includes a servo electric cylinder (not shown in the figure) and a probe 310. The servo electric cylinder can drive the probe 310 to move closer to or further away from the battery device. As a high-precision power source, the push rod speed of the servo electric cylinder can be precisely controlled between 5 mm per second and 80 mm per second, and the push rod speed of the servo electric cylinder can be adjusted according to actual needs.

[0036] like Figure 2 As shown, the servo electric cylinder and the probe 310 are connected by an insulating component 320, which can reduce the risk of the battery cell, probe 310, battery device housing and servo electric cylinder being connected to form an external conductive circuit. This reduces the risk of premature ignition of the battery device caused by a short circuit in the external conductive circuit during the test, and can improve the accuracy of the test structure, so as to accurately evaluate the safety performance of the battery device.

[0037] The connection methods between the probe 310 and the insulating component 320 include, but are not limited to, bonding, riveting, snap-fitting, interference fit, fastener connection, etc. Fasteners include, but are not limited to, screws, bolts, pins, etc. The embodiments of this application do not impose special limitations on the connection methods between the probe 310 and the insulating component 320.

[0038] The connection methods between the push rod of the servo electric cylinder and the insulating component 320 include, but are not limited to, bonding, riveting, snap-fitting, interference fit, fastener connection, etc. Fasteners include, but are not limited to, screws, bolts, pins, etc. The embodiments of this application do not impose special limitations on the connection methods between the push rod of the servo electric cylinder and the insulating component 320.

[0039] The insulating component 320 can be made of high-strength insulating material through precision machining. For example, the insulating component 320 is made of polyetheretherketone (PEEK), which gives it high strength, high rigidity, high heat resistance, high electrical insulation, and high flame retardancy. The insulating component 320 can also be made of polyimide, polyetherimide, polyphenylene sulfide, special epoxy resin composite materials, etc. This application does not impose any special limitations on the material of the insulating component 320.

[0040] The push rod of the servo electric cylinder and the insulating part 320 can be connected by a pressure sensor. During the process of the probe 310 piercing the battery device, the pressure sensor can measure the reaction force applied by the battery device to the probe 310. By measuring time, force, and displacement of the probe 310, the dynamic sequence and severity of damage to the internal structure of the battery device during the piercing process can be visualized and quantified. For example, the time it takes for the probe 310 to pierce the battery module shell, battery pack shell, cell shell, separator, etc. can be obtained by measuring time, force, and displacement.

[0041] The pressure sensor is a high-precision force sensor. A high-precision force sensor needs to cover the expected maximum penetration force. For example, a high-precision force sensor can measure forces between 0 and 50 kN. This application embodiment does not specifically limit the measurement range of the high-precision force sensor, but is only an example.

[0042] Figure 3 for Figure 2 The diagram shows the structure of the probe in some embodiments. For example... Figure 3 As shown, the probe 310 includes a rod 311 and an insertion end 312. Along the axial direction K of the probe 310, both ends of the rod 311 are connected to the insulating member 320 and the insertion end 312, respectively. That is, the insertion end 312 is located at the end of the rod 311 furthest from the servo electric cylinder. Along the axial direction K of the probe 310, and along the direction from the rod 311 towards the insertion end 312, i.e., along... Figure 3 In the direction indicated by the arrow of the axial direction K of the probe 310, the cross-sectional area of ​​the insertion end 312 gradually decreases. The cross-section of the insertion end 312 refers to the cross-section obtained by cutting the insertion end 312 along a plane perpendicular to the axial direction K of the probe 310. The gradual decrease in the cross-section of the insertion end 312 makes the insertion end 312 have a pointed tip, which can reduce the difficulty of the insertion end 312 penetrating the battery device.

[0043] The probe 310 is made of a high-temperature resistant conductive material. The conductive material can be a metal, a metal alloy, or other materials. This application does not impose any special limitations on the material of the probe 310. For example, the probe 310 is a high-strength, high-temperature resistant tungsten steel needle. While ensuring the rigidity of the probe 310, it can also make the probe 310 have a high sharpness, which can further reduce the difficulty of the probe 310 piercing the battery device.

[0044] For example, the 310 probe is typically a tungsten steel needle with a diameter of 5 mm to 10 mm that can withstand high temperatures of 800°C. The tip cone angle is 45° to 60°. It requires tempering or quenching treatment and chrome plating.

[0045] The outer surface of the rod 311 is covered with a first insulating layer. The insertion end 312, made of conductive material, is not covered with the insulating layer, leaving the conductive insertion end 312 exposed. After the probe 310 penetrates the battery device, the insertion end 312 can simultaneously contact the positive and negative electrodes of the battery cell and the separator, forming a conductive circuit inside the battery cell with the positive and negative electrodes of the battery cell and the insertion end 312. At the same time, during the process of the probe 310 penetrating the battery device, the first insulating layer can make the rod 311 insulated from the battery device, reducing the risk of the rod 311 forming a conductive circuit outside the battery cell through electrical contact with the metal shell, external conductors, and other structures of the battery device. This reduces the risk of premature ignition of the battery device due to a short circuit caused by an external conductive circuit during the test, improving the accuracy of the test structure and facilitating a precise assessment of the safety performance of the battery device.

[0046] The first insulating layer can be formed on the outer surface of the rod 311 by means of micro-arc oxidation, plasma spraying, etc. The embodiments of this application do not impose special limitations on the formation method of the first insulating layer. For example, micro-arc oxidation or plasma spraying of alumina ceramic can be performed on the entire outer surface of the rod 311 to form a dense, high-hardness (HV>1000), high-insulation (withstand voltage>1000V), and high-temperature resistant (>1000℃) first insulating layer.

[0047] The first insulating layer has the properties of high temperature resistance and insulation. The embodiments of this application do not make special limitations on the material of the first insulating layer. The above-mentioned alumina ceramic is only an example of the material of the first insulating layer and is not a specific limitation on the material of the first insulating layer. For example, the first insulating layer can also be a polymer film, an inorganic film, etc.

[0048] Figure 4 for Figure 3 The rod in the middle is shown in cross-sectional views in some embodiments. For example... Figure 3 and Figure 4As shown, the rod 311 has a receiving groove 313, in which a temperature sensor (not shown) is installed. The temperature sensor is bonded and fixed to the rod 311. During the process of the probe 310 piercing the battery device, the temperature of the battery device can be transmitted to the temperature sensor through the rod 311. The temperature of the battery device can be detected in real time by the temperature sensor to determine whether the battery device has thermal runaway. That is, the time of thermal runaway of the battery device can be determined by the temperature detected by the temperature sensor and the time when the temperature begins to rise, so as to facilitate the subsequent analysis of the thermal runaway of the battery device.

[0049] In addition, resistance strain gauges can be attached to the surface of the battery device. When the physical shape of the battery device changes, the shape of the resistance strain gauge also changes, causing the resistivity of the electronic strain gauge to change. The electronic strain gauge can indirectly and in real time reflect the gas generation rate and pressure accumulation process inside the battery device. It can be combined with the temperature, physical shape changes and time of the battery device to evaluate the triggering mechanism, propagation path and dynamic evolution process of thermal runaway.

[0050] like Figure 3 and Figure 4 As shown, the receiving groove 313 has an opening on the side wall of the rod 311. The temperature sensor is installed into the receiving groove 313 through the opening, and high-temperature resistant inorganic adhesive is injected into the receiving groove 313 through the opening. The high-temperature resistant inorganic adhesive fills and seals the receiving groove 313 and the opening. After the high-temperature resistant inorganic adhesive cures, the temperature sensor is fixed inside the rod 311.

[0051] After the high-temperature resistant inorganic adhesive has cured, the exposed part of the high-temperature resistant inorganic adhesive at the opening can be sanded to make the surface of the high-temperature resistant inorganic adhesive flush with the surface of the rod 311. Taking the outer surface of the rod 311 as an example, the exposed surface of the high-temperature resistant inorganic adhesive at the opening can form a complete circular surface with the outer surface of the rod 311, thereby improving the overall smoothness of the probe 310 surface and reducing the risk of local protrusions or depressions at the opening of the probe 310.

[0052] The surface of the temperature sensor is covered with an insulating layer to reduce the risk of short circuit by the rod 311.

[0053] For example, along the axial direction K of the probe 310, a semi-circular receiving groove 313 is precision milled into the surface of the probe 310. The depth of the receiving groove 313 is controlled between 0.8 mm and 1.2 mm. The depth of the receiving groove 313 refers to the radial dimension along the probe 310. A type K thermocouple temperature sensor is pre-embedded in the receiving groove 313, and the surface of the type K thermocouple temperature sensor is covered with an insulating layer made of ceramic material. After the type K thermocouple temperature sensor is embedded in the receiving groove 313, the gap between the type K thermocouple temperature sensor and the rod 311 is filled with high-temperature resistant inorganic adhesive (such as alumina-based adhesive) to ensure that the type K thermocouple temperature sensor and the rod 311 are tightly fitted. After the high-temperature resistant inorganic adhesive is cured, the surface is polished so that the high-temperature resistant inorganic adhesive is flush with the outer circle of the rod 311.

[0054] The probe 310 may also include a connecting wire (not shown in the figure), one end of which is electrically connected to the insertion end 312, and the other end of which is used to electrically connect to an electrochemical impedance spectroscopy (EIS) analysis module. The EIS analysis module can generate an AC excitation signal in the microampere range with a frequency range of 0.1 Hz to 100 kHz and inject it into the battery device through the probe 310, while simultaneously measuring the response signal of the battery device with high precision.

[0055] The probe 310, connected to the EIS analysis module, can be used to monitor the dynamic evolution of electrochemical parameters such as short-circuit resistance (Rs) and charge transfer impedance (Rct) inside the battery device in real time during insertion. Analyzing a sudden drop in Rs in the EIS spectrum can determine the severity of the internal short circuit, thus identifying whether a hard or soft short circuit has occurred. Furthermore, analyzing changes in Rct reflects the state evolution of the electrochemical interface around the short circuit point. Specifically, when a conductive path with almost zero resistance is formed inside or outside the battery device, the insulating membrane between the positive and negative electrodes completely fails, resulting in direct contact between the electrodes, or direct contact between the positive and negative electrodes through a medium with almost zero resistance. In this case, a hard short circuit occurs. When a local connection is formed between the positive and negative electrodes of the battery cell through a weak, high-resistance channel (this channel may be incomplete or have poor conductivity), a soft short circuit occurs.

[0056] The probe 310 can be configured with only a temperature sensor without being connected to the EIS analysis module. Alternatively, the probe 310 can be connected to the EIS analysis module without a temperature sensor. Or, the probe 310 can be configured with both a temperature sensor and be connected to the EIS analysis module.

[0057] In this embodiment, the probe 310 is equipped with both a temperature sensor and is connected to the EIS analysis module, which can evaluate the thermal runaway time and internal short-circuit evolution process of the battery device through temperature, Rs, and Rct.

[0058] like Figure 2 As shown, the test assembly 300 also includes an insulating base 330. The servo electric cylinder is mounted on the base 100 via the insulating base 330. The insulating base 330 can reduce the risk of the battery device, the test assembly 300 and the base 100 being connected to form an external conductive circuit, thereby reducing the risk of premature ignition caused by the battery device being short-circuited by the external conductive circuit during the test. This can improve the accuracy of the test structure and facilitate the accurate evaluation of the safety performance of the battery device.

[0059] The insulating base 330 can be made of both metal and insulating material. For example, the insulating base 330 includes a metal substrate surrounded by an insulating material, giving the insulating base 330 both high structural strength and good insulation. For example, the insulating base 330 can be made of aluminum alloy and high-strength epoxy resin insulating board or polyetheretherketone material. This application does not impose any special limitations on the material and structure of the insulating base 330.

[0060] like Figure 1 and Figure 2 As shown, the testing device also includes a rotating mechanism 400. The insulating base 330 is mounted on the base 100 via the rotating mechanism 400. The rotating mechanism 400 can drive the insulating base 330 to rotate around a first direction X and / or a second direction Y. The insulating base 330 drives the probe 310 to rotate, so that the probe 310 can penetrate the battery device at a preset angle. The first direction X and the second direction Y are both perpendicular to the height direction Z of the testing device.

[0061] The rotating mechanism 400 includes a drive motor (not shown in the figure) and a rotary bearing (not shown in the figure). The inner ring of the rotary bearing is connected to the output shaft of the drive motor, and the outer ring of the rotary bearing is connected to the insulating base 330. The drive motor can drive the insulating base 330 to rotate through the rotary bearing, so that the probe 310 rotates at a preset angle, and the insertion angle of the probe 310 on the battery device can be adjusted.

[0062] In this embodiment, by setting a rotating mechanism 400, it is possible to simulate foreign objects penetrating the battery device from multiple angles, thereby improving the reliability of the test results.

[0063] When the rotating mechanism 400 can drive the test component 300 to rotate around the first direction X and the second direction Y, the rotating mechanism 400 includes a first mechanism and a second mechanism. The first mechanism is mounted on the base 100, the second mechanism is mounted on the first mechanism, and the insulating base 330 is mounted on the second mechanism. The first mechanism can drive the second mechanism to rotate around the first direction X, thereby driving the test component 300 to rotate around the first direction X. The second mechanism can also directly drive the test component 300 to rotate around the second direction Y, which can improve the degree of freedom of rotation of the test component 300.

[0064] like Figure 1 and Figure 2 As shown, the base 100 includes a frame 110, and the support platform 200 is installed on the frame 110. The frame 110 can be welded from high-rigidity steel, making the frame 110 a gantry or box structure, providing a stable foundation for the entire system and possessing extremely high vibration and impact resistance.

[0065] The base 100 may also include a first rod 120 mounted on the frame 110. The first rod 120 extends along a first direction X. A rotating mechanism 400 is mounted on the first rod 120. When the test device is in the debugging state, the rotating mechanism 400 can move relative to the first rod 120 along the first direction X, so that the test component 300 can be moved to a preset position. Then, the rotating mechanism 400 and the first rod 120 are locked and fixed by the first fastener 122. That is, the relative movement of the rotating mechanism 400 and the first rod 120 is restricted by the first fastener 122, so that the test component 300 is fixed in the preset test position, so that the test device can enter the test state. That is, when the test device is in the test state, the rotating mechanism 400 and the first rod 120 are locked and fixed by the first fastener 122.

[0066] In this embodiment, the test component 300 can be positioned along the first direction X, enabling the test device to perform multi-position and multi-angle tests on the battery device, thereby improving the accuracy and reliability of the test results.

[0067] The number of first rods 120 can be one or more. This application embodiment does not impose a special limitation on the number of first rods 120.

[0068] The first rod 120 may be provided with a first sliding member 121, and the rotating mechanism 400 is fixed on the first sliding member 121. The position of the first sliding member 121 on the first rod 120 is adjustable by the first fastener 122.

[0069] Figure 5 This is a schematic diagram of the connection structure between the first rod and the rotating mechanism in the first embodiment. Figure 5 As shown, the first rod body 120 is provided with a plurality of mounting holes 123 arranged along the first direction X. One end of the first fastener 122 passes through the first slider 121 and is connected to the mounting hole 123. The first fastener 122 is installed on different mounting holes 123 to realize the position of the first slider 121 and the test component 300 on the first slider 121 in the first direction X.

[0070] Figure 6 This is a cross-sectional view of the connection structure between the first rod and the rotating mechanism in the second embodiment. (See image.) Figure 6 As shown, the first sliding member 121 is sleeved on the first rod body 120, and the first fastener 122 can be inserted into the first sliding member 121. By tightening the first fastener 122, the first fastener 122 abuts against the first rod body 120, thereby clamping the first rod body 120 in the second direction Y by the first fastener 122 and the first sliding member 121, thus achieving the limiting and fixing of the first rod body 120 and the first sliding member 121.

[0071] Figure 7 This is a cross-sectional view of the connection structure between the first rod and the rotating mechanism in the third embodiment. Figure 7 As shown, a U-shaped first sliding member 121 is sleeved on the first rod body 120, and a first fastener 122 passes through the two free ends 1211 of the first sliding member 121. By tightening the first fastener 122, the distance between the two free ends 1211 in the second direction Y is reduced, thereby causing the first sliding member 121 to clamp the first rod body 120, thus achieving the limiting and fixing of the first rod body 120 and the first sliding member 121.

[0072] Figure 5 , Figure 6 and Figure 7 This is merely a schematic diagram of the structure of the first rod and the first slider. Adjustable connection between the two can also be achieved through other structural forms. This application embodiment does not impose any special limitations on the connection structure between the first rod 120 and the first slider 121.

[0073] One or more first sliding members 121 may be provided on a first rod 120, and one or more test components 300 may be provided on a first sliding member 121. In this embodiment of the application, the number of first sliding members 121 is not specifically limited. By setting multiple first sliding members 121 and multiple test components 300, needle penetration tests can be performed simultaneously from multiple positions to simulate multiple objects piercing the battery device at the same time during a vehicle collision, making the test results more accurate and reliable.

[0074] like Figure 1As shown, the base 100 also includes a second rod 130 extending along the second direction Y. The first rod 120 is installed on the second rod 130. When the test device is in the debugging state, the first rod 120 can move relative to the second rod 130 along the second direction Y, so that the first rod 120 drives the test component 300 to move along the second direction Y, so that the test component 300 can be moved to a preset position. Then, the first rod 120 and the second rod 130 are locked and fixed by the second fastener, that is, the relative movement of the first rod 120 and the second rod 130 is restricted by the second fastener, so that the test component 300 is fixed in the preset test position, so that the test device can enter the test state. That is, when the test device is in the test state, the first rod 120 and the second rod 130 are locked and fixed by the second fastener.

[0075] In this embodiment, the test component 300 can be positioned along the second direction Y, enabling the test device to perform multi-position and multi-angle tests on the battery device, thereby improving the accuracy and reliability of the test results.

[0076] The number of the second rod 130 can be one or more. This application embodiment does not impose a special limitation on the number of the second rod 130.

[0077] The second rod 130 may be provided with a second sliding member, the first rod 120 is fixed on the second sliding member, and the position of the second sliding member on the second rod 130 is adjustable by a second fastener. The connection structure of the second rod 130 and the second fastener can be referred to Figure 5 , Figure 6 and Figure 7 As shown, details will not be elaborated upon here, except... Figure 5 , Figure 6 and Figure 7 In addition to the structure shown, the adjustable connection between the second rod 130 and the second fastener can also be achieved through other structural forms. The embodiments of this application do not impose special limitations on the connection structure between the second rod 130 and the second sliding member.

[0078] Figure 8 This is a top view of the testing apparatus in some embodiments. Figure 8 An example is shown where two second rods 130 are arranged on both sides along a first direction X, and two first rods 120 are arranged along a second direction Y, with at least one test component 300 provided on each of the two first rods 120.

[0079] Figure 9 for Figure 1 A schematic diagram of the test device in the first direction X. Figure 10 for Figure 1 A schematic diagram of the testing device in the second direction Y. (See diagram below.) Figure 1 , Figure 9 and Figure 10 As shown, the support platform 200 includes a bracket 210, which is mounted on the base 100, i.e., the bracket 210 is mounted on the frame 110. The bracket 210 has a support surface 211 for supporting the battery device. The support surface 211 is covered with a second insulating layer. The second insulating layer can reduce the risk of the battery device being directly connected to the test device to form an external conductive circuit, thereby reducing the risk of premature ignition caused by the battery device being short-circuited by the external conductive circuit during the test. This can improve the accuracy of the test structure, so as to accurately evaluate the safety performance of the battery device.

[0080] The bracket 210 can be made of high-strength steel by computer numerical control (CNC). The contour shape of the supporting surface 211 can be compatible with the bottom shape of mainstream battery devices on the market, providing large-area support, dispersing pressure, reducing the risk of local deformation of the battery device, and improving the accuracy and reliability of test results.

[0081] like Figure 1 , Figure 9 and Figure 10 As shown, the support platform 200 also includes a clamping member 220 mounted on the bracket 210. The clamping member 220 has a clamping portion 221. Along the height direction Z of the test device, the gap between the clamping portion 221 and the support surface 211 is used to accommodate the battery device. The clamping portion 221 is used to abut against the battery device in the height direction Z of the test device. When the test device is in the debugging state, the clamping member 220 can move relative to the bracket 210 along the height direction Z of the test device. When the clamping portion 221 and the battery device are at the height of the test device... After contact in the Z direction, the clamping part 220 and the bracket 210 can be locked and fixed by the third fastener, so that the clamping part 221 and the bracket 210 clamp the battery device in the height direction Z of the test device, so that the test device can enter the test device. That is, when the test device is in the test state, the clamping part 220 and the bracket 210 are locked and fixed by the third fastener, which reduces the risk that the battery device will be pushed up by the probe 310 during the process of the probe 310 piercing the battery device, and can improve the accuracy of the piercing depth and position of the probe 310.

[0082] The portion of the clamping member 220 that comes into contact with the battery device can be covered with a high-temperature resistant insulating layer, such as ceramic or polyetheretherketone, thereby reducing the risk of the battery device and the clamping member 220 forming an external conductive circuit.

[0083] The specific structure of the adjustable connection between the clamping member 220 and the bracket 210 in the height direction Z of the testing device can be referred to Figure 5 , Figure 6 and Figure 7 The structure shown will not be elaborated upon here, except... Figure 5 , Figure 6 and Figure 7 In addition to the structure shown, the adjustable connection between the clamping member 220 and the bracket 210 can also be achieved through other structural forms. The embodiments of this application do not impose special limitations on the connection structure between the clamping member 220 and the bracket 210.

[0084] Based on the testing device in any of the above embodiments, the second aspect of this application provides a testing system. The testing system includes a controller, which can be connected to the servo electric cylinder and the rotating mechanism 400 described above. That is, the controller can control the linkage of all the motors, electric cylinders, cylinders and other structures included in the testing system, which can facilitate the improvement of the accuracy of the position, angle, force and distance of the probe 310 piercing the battery device, and improve the accuracy and reliability of the test results.

[0085] The testing system also includes a data acquisition module. The aforementioned temperature sensor, EIS analysis module, pressure sensor, electronic strain gauge, and other devices can all be connected to the data acquisition module. The data acquisition module can collect data such as temperature, Rs, Rct, physical deformation, and penetration force in real time, and correlate these data with time. Then, the data and time are transmitted to the computer, which processes the data and time to generate corresponding time-force-displacement curves, multi-channel temperature-strain curves, and electrochemical impedance spectroscopy sequences (EIS spectrometer sequences).

[0086] The testing system may also include an observation module, which can be a miniature pinhole camera, a high-temperature resistant industrial endoscope, or an infrared imaging device. By placing the observation module on the outside or inside of the battery device, the module is aligned with a preset insertion point or critical parts such as an explosion-proof valve. The observation module is then connected to a data acquisition module, which can collect physical structural information of the observation location in real time. This information includes, but is not limited to, structural damage, electrolyte leakage, smoke, and spark generation. The observation module can transmit this physical structural information to the data acquisition module in real time. The data acquisition module correlates the physical structural information with time and then transmits it to a computer. The computer generates a physical image of the battery device based on the time and physical structural information. This physical image can be a photograph or video, forming intuitive visual evidence.

[0087] The data acquisition module can also connect to the voltage and current sensors in the battery device, enabling the data acquisition module to collect the voltage and current data of the battery device in real time. The data acquisition module correlates the voltage and current data with time and transmits them to the computer. The computer generates a VI curve (Voltage-Current curve) based on the voltage, current data and time.

[0088] Furthermore, the computer can be equipped with control software. The operator can input parameters such as the number of insertion points, insertion position, insertion angle, insertion force, insertion depth, and insertion speed through this software. The control software can then precisely synchronize the movement of all probes 310 based on these input parameters, ensuring the probe 310's movement error is within ±2ms. The control software can also collect computer-generated time-force-displacement curves, multi-channel temperature-strain curves, electrochemical impedance spectroscopy sequences, VI curves, and physical images. The operator can directly access these curves and physical images through the control software, enabling real-time monitoring of the testing process and the real-time status of the battery device.

[0089] The control software can also save these curves, photos, and videos so that operators can retrieve them after the test. The control software can also perform fault diagnosis based on the curves, photos, and videos, and automatically generate a structured diagnostic report. The diagnostic report can include the fault triggering mode, triggering time, precise location, internal short circuit evolution process assessment, and mechanism diagnosis conclusion.

[0090] Based on the testing system in any of the above embodiments, a third aspect of this application provides a needle penetration test method for a battery device, the needle penetration test method comprising: Place the battery device on the support platform 200 of the test device; The controller controls the test component 300 to move to a preset position, and the controller controls the probe 310 to rotate to a preset angle; The controller drives the probe 310 to pierce the battery device via a servo electric cylinder. During the process of probe 310 piercing the battery device, the temperature sensor synchronously collects the temperature information of the battery device and transmits the temperature information to the data acquisition module in real time. The data acquisition module also collects the resistance value of the resistance strain gauge in real time. The data acquisition module simultaneously collects voltage and current data from the battery device; The data acquisition module transmits temperature, voltage, current, and time information to the computer in real time. Computer-generated multi-channel temperature-strain curves and VI curves; The computer extracts the time T1 corresponding to the peak temperature abrupt change from the temperature-strain curve; The computer extracts the start time T2 of voltage and current abrupt changes from the VI curve; Computer comparison of T1 and T2; If T1 is earlier than T2, the computer determines that the battery device was punctured by probe 310 first, and then thermal runaway occurred. If T2 occurs before T1, the computer determines that the battery device experiences an internal short circuit first, followed by thermal runaway. The computer generates a test report based on the judgment results.

[0091] For example, the specific steps of the needle prick test method include: Place the battery device on the support platform 200 of the test device; Adjust the mounting position of the clamping member 220 on the bracket 210 so that the clamping member 220 abuts against the battery device, and lock the clamping member 220 and the bracket 210 with the third fastener, and clamp the battery device with the clamping member 220 and the bracket 210. Adjust the mounting position of the first rod 120 on the second rod 130, adjust the mounting position of the first sliding member 121 on the first rod 120, and adjust the angle of the probe 310 through the rotating mechanism 400 so that the probe 310 reaches the preset position and angle. The computer's control software sends instructions to the controller, which in turn controls the servo electric cylinder to work. The servo electric cylinder drives the probe 310 to approach and penetrate the battery device. During the process of probe 310 piercing the battery device, the pressure sensor collects the piercing force of probe 310 in real time and transmits the piercing force to the data acquisition module. The temperature sensor collects the temperature of the battery device in real time and transmits the temperature to the data acquisition module; The observation module collects physical structure information of the observation location in real time and transmits the physical structure information to the data acquisition module; The EIS analysis module injects the excitation signal into the battery device through probe 310, while simultaneously measuring the response signal of the battery device with high precision, and transmitting electrochemical parameters such as Rs and Rct to the data acquisition module. The data acquisition module collects the resistance value of the resistance strain gauge, the voltage data and current data of the battery device in real time, and transmits the time, penetration force, temperature, resistance value of the resistance strain gauge, voltage data of the battery device, current data of the battery device, Rs, Rct, and physical structure information to the computer control software in real time. Based on the above information, the control software generates corresponding Time-Force-Displacement curves, Multi-Channel Temperature-Strain curves, EIS Spectrum sequences, Voltage-Current curves, and physical images; The control software extracts characteristic force points from the Time-Force-Displacement curve. These characteristic force points correspond to the moments when the probe 310 punctures different layers of the battery device, such as the water-cooling plate, outer casing, aluminum cell casing, and separator. The control software extracts the onset time T1 of the temperature surge, the changes, the peak temperature, and the time corresponding to the temperature change from the Multi-Channel Temperature-Strain curve; The control software extracts the start time T2 of voltage sag and current surge from the voltage-current curve; The control software extracts the numerical variation curves of Rs and charge transfer impedance Rct from the EIS Spectrum sequence; The control software extracts the start time T3 of visible physical phenomena from the physical image. Visible physical phenomena can be the first frame of sparks, the first frame of smoke, etc. In addition, visible physical phenomena can also be extracted from the physical image through manual marking. The control software compares T1 and T2; If T2 occurs earlier than T1, it indicates that an internal short circuit (electrical failure) occurs first. The large amount of Joule heat generated by the local short circuit will further damage the separator of the cell, causing the short circuit area to expand further, forming positive feedback, accelerating the short circuit heat release, and even further triggering the decomposition and reaction of the electrode material. This thermal runaway (thermal failure) mainly caused by Joule heat is dominated by physics and electricity. If T1 occurs before T2, it may be due to mechanical puncture damaging the battery structure, leading to thermal runaway caused by a large amount of heat released by the chemical reaction inside the cell, i.e., chemical reaction dominates. In addition, the control software can also match the temperature anomaly probe 310 with the corresponding observation module, extract the physical image observed by the observation module at the corresponding location, and spatially match the physical location of the abnormal temperature with the smoke / spark point observed in the physical image to accurately locate the battery pack or even the cell that has thermal runaway. Furthermore, the control software can also assist in the analysis of the physical and chemical reactions and thermal runaway process inside the battery through the macroscopic physical phenomena of the battery device during the needle penetration process.

[0092] The control software can also determine the severity of the internal short circuit of the battery device by the sudden drop in Rs in the EIS sequence spectrum, thereby determining whether the battery device has a hard short circuit or a soft short circuit. The control software can also reflect the state evolution of the electrochemical interface around the short circuit point by the change in Rct in the EIS sequence spectrum.

[0093] The control software can also analyze the coupling relationship between mechanical damage and electrochemical failure by combining the Time-Force-Displacement curve.

[0094] Finally, the control software automatically generates a structured diagnostic report based on the above analysis. The diagnostic report may include the fault triggering mode, triggering time, precise location, internal short circuit evolution process assessment, and mechanism diagnostic conclusions.

[0095] In summary, the testing device provided in this application embodiment can adjust the position and angle of the probe 310 through the first rod 120, the first sliding member 121, and the rotating mechanism 400. Combined with the arrangement of multiple testing components 300, it can simulate various complex bottom collision scenarios with synchronous impacts at multiple points, different angles, and different positions.

[0096] By setting the bracket 210 and the clamping element 220, a locking force far exceeding the reaction force of the probe 310 can be provided, which can improve the accuracy of the insertion depth and position of the probe 310.

[0097] By setting an insulating base 330, an insulating component 230, and a first insulating layer on the surface of the rod 311, the risk of premature ignition caused by a short circuit in the external conductive circuit during the test is reduced, which can improve the accuracy of the test structure and facilitate accurate evaluation of the safety performance of the battery device.

[0098] By integrating pressure sensors, EIS analysis modules, and observation modules, the detailed process of the coupling changes of multiple physical fields (electricity, heat, and force) inside the battery device during the test can be observed intuitively, which facilitates the evaluation of fault triggering modes, triggering times, precise locations, and internal short-circuit evolution processes.

[0099] By using computers to correlate and analyze data from different sources and with different physical meanings under a unified time scale, it is possible not only to determine whether a battery has failed, but also to accurately diagnose the onset time, evolution path and root cause of the fault, which has direct and efficient guiding value for improving the safety design of battery devices.

[0100] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A testing apparatus for performing a nail penetration test on a battery device, characterized in that, The testing apparatus includes: Base (100); A support platform (200) is installed on the base (100) for supporting the battery device; The test assembly (300) is mounted on the base (100) along the height direction (Z) of the test device, and the test assembly (300) is located on the side of the support platform (200) away from the battery device. The test assembly (300) includes a servo electric cylinder and a probe (310), which are connected by an insulator (320). The servo electric cylinder is capable of driving the probe (310) to move toward or away from the battery device.

2. The testing apparatus according to claim 1, characterized in that, The probe (310) includes a rod (311) and an insertion end (312). Along the axial direction (K) of the probe (310), the insertion end (312) is located at the end of the rod (311) away from the servo electric cylinder. Along the axial direction (K) of the probe (310) and in the direction of the rod (311) pointing towards the insertion end (312), the cross-sectional area of ​​the insertion end (312) gradually decreases; The outer surface of the rod (311) is covered with a first insulating layer.

3. The testing apparatus according to claim 2, characterized in that, The rod (311) has a receiving groove (313), in which a temperature sensor is disposed, and the temperature sensor is bonded and fixed to the rod (311); and / or, The probe (310) also includes a connecting wire, one end of which is electrically connected to the insertion end (312), and the other end of which is used for electrical connection to the EIS analysis module.

4. The testing apparatus according to claim 1, characterized in that, The test assembly (300) also includes an insulating base (330), through which the servo electric cylinder is mounted on the base (100).

5. The testing apparatus according to claim 4, characterized in that, The testing device further includes a rotating mechanism (400), and the insulating base (330) is mounted on the base (100) via the rotating mechanism (400). The rotating mechanism (400) can drive the insulating base (330) to rotate around a first direction (X) and / or a second direction (Y).

6. The testing apparatus according to claim 5, characterized in that, The base (100) includes a first rod (120) extending along the first direction (X), and the rotating mechanism (400) is mounted on the first rod (120). When the testing device is in the debugging state, the rotating mechanism (400) can move relative to the first rod (120) along the first direction (X); When the testing device is in the testing state, the rotating mechanism (400) and the first rod (120) are locked and fixed by the first fastener (122); The base (100) further includes a second rod (130) extending along the second direction (Y), and the first rod (120) is mounted on the second rod (130). When the testing device is in the debugging state, the first rod (120) can move relative to the second rod (130) along the second direction (Y); When the testing device is in the testing state, the first rod (120) and the second rod (130) are locked and fixed by the second fastener.

7. The testing apparatus according to claim 1, characterized in that, The support platform (200) includes a bracket (210) mounted on the base (100), the bracket (210) having a support surface (211) for supporting the battery device, the support surface (211) being covered with a second insulating layer.

8. The testing apparatus according to claim 7, characterized in that, The support platform (200) further includes a clamping member (220) installed on the bracket (210), the clamping member (220) having a clamping portion (221) along the height direction (Z) of the test device, the gap between the clamping portion (221) and the support surface (211) is used to accommodate the battery device, and the clamping portion (221) is used to abut against the battery device in the height direction (Z) of the test device; When the testing device is in the debugging state, the clamping member (220) can move relative to the bracket (210) along the height direction (Z) of the testing device; When the testing device is in the testing state, the clamping member (220) and the bracket (210) are locked and fixed by a third fastener.

9. The testing apparatus according to any one of claims 1 to 8, characterized in that, The servo electric cylinder is connected to the insulating component (320) via a pressure sensor.

10. The testing apparatus according to any one of claims 1 to 8, characterized in that, The plurality of test components (300) are arranged along a first direction (X) and / or a second direction (Y).

11. A testing system, characterized in that, The testing system includes the testing apparatus according to any one of claims 1 to 10; The testing system also includes a controller, which is connected to the servo electric cylinder of the testing device.

12. The testing system according to claim 11, characterized in that, The testing system also includes a data acquisition module and an observation module. The observation module and the controller are respectively connected to the data acquisition module, and the observation module is used to observe the battery device.

13. The testing system according to claim 11, characterized in that, The testing system also includes a data acquisition module and a resistance strain gauge. The resistance strain gauge and the controller are respectively connected to the data acquisition module. The resistance strain gauge is used to fit onto the surface of the battery device.

14. A method for a nail penetration test of a battery device, comprising performing a nail penetration test on the battery device using the test system according to any one of claims 11 to 13, characterized in that, The acupuncture test method includes: The battery device is placed on the support platform (200) of the test device; The controller controls the test component (300) to move to a preset position, and the controller controls the probe (310) to rotate to a preset angle; The controller drives the probe (310) to pierce the battery device via the servo electric cylinder.

15. The needle penetration test method for the battery device according to claim 14, characterized in that, During the process of the probe (310) penetrating the battery device, the needle penetration test method includes: The temperature sensor synchronously collects temperature information and transmits the temperature information to the data acquisition module in real time, while the data acquisition module collects the resistance value of the resistance strain gauge in real time. The data acquisition module synchronously acquires the voltage and current data of the battery device; The data acquisition module transmits the temperature information, voltage data, current data, and time information to the computer in real time. The computer generates multi-channel temperature-strain curves and VI curves.

16. The needle penetration test method for the battery device according to claim 15, characterized in that, The acupuncture test method includes: The computer extracts the time T1 corresponding to the temperature abrupt change from the temperature-strain curve; The computer extracts the start time T2 of voltage and current abrupt changes from the VI curve; The computer compares T1 and T2; If T1 is earlier than T2, the computer determines that the battery device was first punctured by the probe (310) and then thermal runaway occurred; If T2 is earlier than T1, the computer determines that the battery device first experiences an internal short circuit and then thermal runaway. The computer generates a test report based on the judgment result.

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