Battery pack bottom scraping test device and test method

Abstract

The invention provides a battery pack bottom scraping test device and method, and relates to the technical field of battery testing, the device comprises a test trolley and a battery pack mounting assembly, and the bottom of a trolley frame is connected with trolley wheels through a suspension assembly; the angle adjusting assembly comprises a lifting structure, a first hand wheel is arranged at one end of the lifting structure, and the other end of the lifting structure abuts against the suspension assembly; the first hand wheel exerts acting force to drive the lifting structure to act, the telescopic part is driven to move, the front portion of the trolley frame is made to ascend or descend, and therefore the inclination angle formed between the battery pack installed on the battery pack installation assembly and the running road surface is changed. The control assembly controls the test trolley to collide with the barrier structure at a target angle and a target test speed; the defect that real safety risks are difficult to expose in an existing test is overcome, test conditions better fitting actual working conditions are provided for battery pack bottom scraping safety performance evaluation, and the accuracy of test results is improved.

Description

Technical Field

[0001] This application generally relates to the field of battery testing technology, and specifically to a battery pack scraping test device and test method. Background Technology

[0002] The battery pack undercarriage scraping test is a safety performance test for electric vehicle batteries. It simulates the situation where the bottom of an electric vehicle is impacted or scraped during driving, in order to evaluate the safety performance of the battery pack under such conditions.

[0003] Existing electric vehicle scraping accidents can be divided into two categories: one is scraping accidents caused by the vehicle colliding with obstacles while in horizontal motion; the other is when the vehicle straddles a curb or a step of a certain height, causing the battery pack to collide with the obstacle. Currently, some testing organizations have developed evaluation conditions for horizontal scraping accidents to assess them. However, these assessment conditions have significant shortcomings. On the one hand, to prevent the battery pack from being hit by obstacles, vehicles are structurally designed with protective devices installed at the front to avoid impact, and sometimes the subframe is adjusted to be lower than the battery pack. This means that obstacles may not hit the battery pack during horizontal scraping tests. On the other hand, even with strong protective devices at the front of the battery pack, a collision between the obstacle and the protective device can cause the vehicle to bounce and fly directly over the obstacle without any contact between the battery pack and the obstacle. These problems make scraping tests difficult to expose true safety risks and can easily mislead the design direction of electric vehicles. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a battery pack scraping test device and test method that improves the authenticity and reliability of the test.

[0005] In a first aspect, this application provides a battery pack scraping test apparatus, comprising: A test trolley, comprising a trolley frame, a battery pack mounting assembly at the bottom of the trolley frame, the battery pack mounting assembly having adjustable mounting space for mounting a battery pack; the bottom of the trolley frame is connected to the trolley wheels via a suspension assembly; An angle adjustment assembly includes: a lifting structure mounted on the trolley frame, one end of which has a first handwheel, and the other end of which forms a telescopic part for abutting against the suspension assembly; the lifting structure is driven to move by applying force through the first handwheel, thereby moving the telescopic part and raising or lowering the front of the trolley frame, thereby changing the tilt angle formed between the battery pack mounted on the battery pack mounting assembly and the road surface, and locking the current tilt angle by fastening bolts when the tilt angle is the target angle; A barrier structure is provided in front of the test rig to simulate road obstacles. A control component is communicatively connected to the test trolley, and the control component is at least used to control the test trolley to collide with the barrier structure at a target angle and a target test speed.

[0006] According to the technical solution provided in this application, the battery pack mounting assembly includes: Multiple battery pack mounting units are disposed at the bottom of the trolley frame and arranged along the traveling direction of the trolley frame; each battery pack mounting unit includes at least: The mounting beam is located at the bottom of the trolley frame and is arranged along the travel direction of the trolley frame; the mounting beam has multiple mounting holes. Two adapters are provided, which are connected to the mounting holes. The mounting space is formed between the adapters of all the battery pack mounting units for mounting the battery pack.

[0007] According to the technical solution provided in this application, it also includes: at least one set of counterweight components disposed on the trolley frame; The counterweight assembly includes: A counterweight bracket is slidably connected to the trolley frame; a counterweight block is provided on the counterweight bracket. An adjustment structure is provided on the trolley frame, and the adjustment structure has an adjustment part and a connecting part, wherein the connecting part is rotatably connected to the counterweight bracket. The force applied by the adjustment part drives the connecting part to rotate, so that the counterweight bracket and the counterweight block move along the trolley frame to the target position.

[0008] According to the technical solution provided in this application, the control component includes: The data acquisition module is used to acquire the target angle and the target test speed; The processing module is used to control the test trolley to collide with the barrier structure at the target angle and the target test speed.

[0009] According to the technical solution provided in this application, the control component further includes: A contact triggering unit is located at the rear end of the trolley frame and is used to send a trigger signal to the braking control unit when the test trolley is subjected to physical collision or pressure. A status monitoring unit is used to generate test status information based on the pressure of the braking system, the battery charge, and the motion status parameters of the test trolley. A braking control unit is electrically connected to the braking system actuator of the test trolley. When the test state information meets the preset state conditions, the braking control unit generates a braking command based on the trigger signal and sends it to the braking system actuator. The braking command is used to instruct the braking system to perform a braking operation.

[0010] According to the technical solution provided in this application, it further includes: a detection component that is communicatively connected to the control component; The detection component includes: A wheel load cell module, which is used to collect the mass of the test trolley; An image acquisition module is used to acquire deformation images of the battery pack during the test. A temperature detection unit is used to collect temperature data of the battery pack after the test. A battery pack insulation testing unit is used to test the insulation performance of the battery pack after testing. A smoke monitoring unit is used to detect smoke emitted from the battery pack after the test; The processing module is used to determine whether to issue an abnormal alarm message based on the temperature data of the battery pack after the test, the insulation performance of the battery pack after the test, and the smoke emission of the battery pack after the test. The processing module is also used to determine the damage location and the transmission path of the impact force of the battery pack based on the deformation image of the battery pack during the test.

[0011] Secondly, this application provides a battery pack scratch test method, implemented based on the aforementioned battery pack scratch test apparatus, the method comprising the following steps: When the test data of the test trolley is adjusted to be the same as the actual vehicle data of the target model, the first height of the road obstacle, the tire radius of the target model and the wheelbase of the target model are obtained. Based on the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle, the target angle between the battery pack and the road surface is calculated, and the tilt angle formed between the battery pack and the road surface is adjusted to the target angle by the angle adjustment component. Select a target impact point on the barrier structure, and obtain the second height between the target impact point and the road surface, as well as the radius of the spherical region of the barrier structure; Based on the target angle, the second height between the target impact point and the road surface, and the radius of the spherical region of the barrier structure, the third height of the highest point of the barrier structure from the road surface is calculated. The height of the highest point of the barrier structure above the road surface is adjusted to the third height, and the barrier structure is positioned in front of the travel path of the test vehicle. The test trolley is controlled to run at the target test speed and collide with the barrier structure at the target angle until the battery pack scrapes from its front end to its rear end to complete the test.

[0012] According to the technical solution provided in this application, the target angle between the battery pack and the road surface is calculated based on the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle. Specifically, this includes the following steps: The difference between the first height of the road obstacle and the tire radius of the target vehicle is taken as the distance by which the tires of the target vehicle are lifted. The target angle is the quotient of the distance the tires of the target vehicle are lifted by dividing the wheelbase of the target vehicle.

[0013] According to the technical solution provided in this application, the test data of the test trolley is adjusted to be the same as the actual vehicle data of the target model, specifically including the following steps: The battery pack is installed in the mounting space of the battery pack mounting assembly, and the test data of the test trolley is obtained; the test data includes at least the initial mass, initial front and rear axle loads, and initial wheelbase; Obtain real vehicle data for the target vehicle model; the target vehicle model refers to the type of vehicle using the current battery pack. Based on the actual vehicle data of the target vehicle model, the initial mass, the initial front and rear axle loads, and the initial wheelbase, determine the mass difference, axle load difference, and wheelbase difference; According to the mass difference and the axle load difference, the counterweights and their relative positions are increased or decreased, and the wheelbase of the trolley is adjusted according to the wheelbase difference until the test data of the test trolley is adjusted to be the same as the actual vehicle data of the target model.

[0014] According to the technical solution provided in this application, the method further includes the following steps: After the experiment was completed, temperature data from multiple points on the battery pack were obtained to obtain a temperature set; If the number of temperature data in the temperature set that exceeds the temperature threshold is greater than a preset number, then temperature anomaly information is generated; Obtain the insulation resistance value between the positive and negative terminals of the battery pack and its casing. If the insulation resistance value is less than or equal to the insulation threshold, generate insulation anomaly information. Obtain the smoke concentration value of the battery pack. If the smoke concentration value is greater than the concentration threshold, generate smoke anomaly information.

[0015] As can be seen from the above technical solution, this application has at least the following beneficial effects: This application provides a battery pack scraping test device, comprising: a test trolley, the test trolley including a trolley frame, a battery pack mounting assembly at the bottom of the trolley frame, the battery pack mounting assembly having an adjustable mounting space for mounting the battery pack; the bottom of the trolley frame is connected to the trolley wheels via a suspension assembly; an angle adjustment assembly, the angle adjustment assembly including: a lifting structure mounted on the trolley frame, one end of the lifting structure having a first handwheel, and the other end forming a telescopic part for abutting against the suspension assembly; the lifting structure is driven to move by applying force through the first handwheel, causing the telescopic part to move, thereby raising or lowering the front of the trolley frame, thereby changing the tilt angle formed between the battery pack mounted on the battery pack mounting assembly and the road surface, and locking the current tilt angle by fastening bolts when the tilt angle is the target angle; a barrier structure, the barrier structure being disposed in front of the test trolley for simulating road obstacles; and a control assembly, the control assembly being communicatively connected to the test trolley, the control assembly being at least used to control the test trolley to collide with the barrier structure at a target angle and a target test speed.

[0016] This application utilizes angle adjustment and control components to accurately simulate actual vehicle undercarriage scraping scenarios and achieve test controllability. Specifically, using a test trolley as the basic carrier, the battery pack mounting components at the bottom of the trolley have adjustable installation space, accommodating different battery pack specifications without frequent trolley replacements, thus improving equipment versatility. The connection design between the trolley frame and suspension components, combined with the lifting structure and first handwheel of the angle adjustment component, allows manual application of force to move the telescopic part, thereby adjusting the tilt angle between the battery pack and the road surface. The target tilt angle is locked with fastening bolts, ensuring accurate and stable test angles. This avoids the problem in traditional horizontal undercarriage scraping tests where the battery pack cannot contact the obstacle due to vehicle protective devices or bounce, effectively reproducing non-horizontal undercarriage scraping scenarios such as vehicles straddling curbs. Simultaneously, the obstacle structure at the front can simulate various road obstacles. Combined with the control components that communicate with the test trolley, it can accurately control the trolley to complete the impact at the target angle and target test speed, ensuring the standardization and controllability of the test process. The device is easy to operate and highly adaptable. It not only solves the problem that existing tests are unable to expose real safety risks, but also provides test conditions that are more in line with actual working conditions for the safety performance evaluation of battery pack scraping. It significantly improves the accuracy and reference value of test results and helps to optimize the safety design of electric vehicle battery packs. Attached Figure Description

[0017] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0018] Figure 1 This is a structural diagram of the battery pack bottom scraping test device.

[0019] Figure 2This is a top view of the battery pack scraping test apparatus.

[0020] Figure 3 This is a side view of the battery pack scraping test apparatus.

[0021] Figure 4 This is a structural diagram of the control and detection components.

[0022] Figure 5 This is a structural diagram of the actuator of the braking system.

[0023] Figure 6 This is an example diagram of wheelbase.

[0024] Figure 7 This is an example diagram showing the relative position of the image acquisition module and the test trolley.

[0025] Figure 8 This is an example diagram of a barrier structure.

[0026] Figure 9 This is a flowchart of the battery pack scraping test method.

[0027] The following components are labeled in the diagram: 1. Trolley frame; 2. Lifting structure; 3. First handwheel; 4. Barrier structure; 5. Mounting beam; 6. Adapter seat; 7. Counterweight bracket; 8. Contact trigger unit; 9. Status monitoring unit; 10. Brake control unit; 11. Wheel load meter module; 12. Image acquisition module; 13. Temperature detection unit; 14. Battery pack insulation detection unit; 15. Smoke monitoring unit; 16. Processing module; 17. Data acquisition module; 18. Cylinder; 19. Solenoid valve; 20. Air tank; 21. Pressure gauge. Detailed Implementation

[0028] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] To make the battery pack scraping test apparatus provided in this application clearer and easier to understand, the apparatus is described below with reference to the accompanying drawings. Figure 1 As shown in the figure, this is a structural diagram of the battery pack scraping test device provided in an embodiment of this application. The device includes: The test trolley includes a trolley frame 1, and a battery pack mounting assembly is provided at the bottom of the trolley frame 1. The battery pack mounting assembly has an adjustable mounting space for mounting the battery pack. The bottom of the trolley frame 1 is connected to the trolley wheels through a suspension assembly. An angle adjustment assembly includes: a lifting structure 2 mounted on the trolley frame 1, one end of the lifting structure 2 having a first handwheel 3, and the other end forming a telescopic part for contacting the suspension assembly; the lifting structure 2 is driven to move by the first handwheel 3, which in turn moves the telescopic part, causing the front of the trolley frame 1 to rise or fall, thereby changing the tilt angle formed between the battery pack mounted on the battery pack mounting assembly and the road surface, and locking the current tilt angle by fastening bolts when the tilt angle is the target angle; Barrier structure 4 is located in front of the test bench vehicle and is used to simulate road obstacles; The control component is connected in communication with the test trolley and is used to control the test trolley to impact the barrier structure 4 at the target angle and target test speed.

[0031] It should be noted that the trolley frame 1 serves as the basic load-bearing frame of the test trolley. The trolley frame 1 has sufficient rigidity to withstand the test impact force and counterweight load. The basic total weight of the test trolley is, for example, 1200±20kg, and the maximum total weight (including counterweight and battery) is, for example, no more than 3500±20kg. The trolley frame 1 has connection interfaces for assembling with components such as suspension components, angle adjustment components, and counterweight components. At the same time, it provides a sliding rail structure for subsequent wheelbase adjustment to ensure that it can match the wheelbase parameters of different vehicle models.

[0032] The battery pack mounting assembly has adjustable mounting space for mounting battery packs of different sizes; specifically, such as... Figure 2 and Figure 3 As shown, the battery pack mounting assembly includes: Multiple battery pack mounting units are provided, located at the bottom of the trolley frame 1 and arranged along the traveling direction of the trolley frame 1; each battery pack mounting unit includes at least: Mounting beam 5 is located at the bottom of the trolley frame 1 and is arranged along the travel direction of the trolley frame 1; multiple mounting holes are provided on the mounting beam 5. Two adapters 6 are connected to the mounting holes; The adapters 6 of all battery pack mounting units form an installation space for mounting the battery pack.

[0033] Here, for example, there are 3 battery pack mounting units. The 3 battery pack mounting units are evenly arranged at the bottom of the trolley frame 1 along the travel direction of the test trolley. This can evenly distribute the weight of the battery pack and prevent the battery pack from shifting due to uneven force during the test impact. At the same time, it provides multiple adjustment points for subsequent adjustment of the installation space, ensuring that battery packs of different sizes can find stable support and fixing points.

[0034] Mounting beam 5 extends beyond the side of the test trolley, expanding the installation space coverage and facilitating battery pack installation and securing operations from both sides of the trolley. The bottom of mounting beam 5 and trolley frame 1 can be connected with M10 bolts. Furthermore, trolley frame 1 has multiple pre-drilled holes, allowing for the connection of mounting beam 5 and trolley frame 1 at different locations using M10 bolts. This enables fine-tuning of the relative positions of mounting beam 5 and trolley frame 1, thus expanding the compatibility range. Mounting beam 5 is made of, for example, high-strength steel to ensure it does not bend or break during test impacts, guaranteeing test safety. The mounting holes are, for example, M12 threaded holes, with a longitudinal spacing of, for example, 100mm. Some mounting holes can be designed as elongated grooves to allow the adapter 6 to be finely adjusted laterally (perpendicular to the direction of travel) within a certain range, preventing misalignment of the adapter 6 with the battery pack's securing interface due to manufacturing errors. By connecting the adapter 6 to mounting holes at different positions, the lateral position of the adapter 6 on the mounting beam 5 can be changed, thereby adjusting the size of the mounting space enclosed by multiple adapters 6 to accommodate battery packs of different widths and with different fixed interface spacings. The adapter 6 and the mounting holes can be connected using M12 bolts.

[0035] Each battery pack mounting unit has two adapter seats 6. The adapter seats 6 of all battery pack mounting units together form an mounting space at the bottom of the trolley frame 1 that is adapted to the corresponding battery pack specifications. The battery packs can be connected one by one with bolts and adapter seats 6, or connected with adapter seats 6 using customized adapter fixtures. Here, the adapter fixture is, for example, a steel plate for welding the battery pack.

[0036] For example, for small battery packs, the two adapter seats 6 on the same mounting beam 5 can be moved closer together, and the relative positions between different battery pack mounting units can be adjusted to reduce the installation space. For large battery packs, the adapter seats 6 can be moved to extend from both ends of the mounting beam 5 onto the sides of the vehicle to expand the installation space.

[0037] By adjusting the size of the installation space that the battery pack mounting components can form, it can adapt to and cover the specifications of mainstream new energy vehicle battery packs. There is no need to design separate installation fixtures or change test trolleys for battery packs of different models, which reduces testing costs, makes operation convenient, and improves testing efficiency.

[0038] During the test, once the barrier structure 4 begins to impact the battery pack, the pressure on the bottom of the battery pack increases as the test trolley moves forward. Due to the suspension at the rear of the test trolley, the rear wheels gradually lift, making the rear movement range of the test trolley more stable and controllable. Here, the bottom of the trolley frame 1 is connected to the trolley wheels through the suspension assembly, enabling better vehicle body movement posture, especially the movement posture after the battery pack impacts the barrier. Specifically, the suspension assembly is a rigid connection structure or a flexible connection structure; the flexible connection structure mainly includes a tower arm, a spring-damping system, a lower control arm, a steering knuckle, and a bearing. The tower arm is bolted to the adapter plate of the trolley frame 1. The upper end of the spring-damping system is bolted to the upper flat plate of the tower arm, and the lower end is bolted to the steering knuckle. The inner end of the lower control arm is connected to the tower arm through a pin, and the lower control arm can rotate relative to the tower arm around the center line of the pin. The outer end of the lower control arm is connected to the steering knuckle through a pin, and the lower control arm can rotate relative to the steering knuckle around the center line of the pin. The steering knuckle is fixed to the bearing by bolts. A spring-damping system allows for relative displacement between the trolley frame 1 and the wheels, making the overall motion of the test trolley more stable and controllable. After the initial impact between the battery pack and the barrier structure 4, due to the constraint of the spring-damping system, the battery pack will undergo multiple consecutive impacts with the barrier structure 4, more closely resembling the motion of a real vehicle. The lower control arm primarily pulls and controls the lateral movement of the wheels. The rigid connection structure is designed with a rigid connection bracket on top of the flexible connection structure. When the height of the test trolley is adjusted to the required position, the rigid connection bracket is used for connection, thus forming a rigid connection. Operators can switch between rigid and flexible connections according to actual needs.

[0039] The lifting structure 2 is located at the front of the trolley frame 1, which refers to the position near the front wheel of the test trolley. One end of the lifting structure 2 is connected to the first handwheel 3, and the other end is a telescopic part used to abut against the front suspension part of the suspension assembly. By rotating the first handwheel 3, the lifting structure 2 is activated, which in turn causes the telescopic part to extend or retract, raising or lowering the front of the trolley frame 1 until the tilt angle formed between the battery pack on the battery pack mounting assembly and the road surface reaches the target angle. Then, the current tilt angle is locked using fastening bolts to prevent angle deviation during the test. Here, the fastening bolts are, for example, M12 bolts. The tilt angle adjustment range is, for example, 0 to 3°, and the adjustment accuracy can be controlled within ±0.3°.

[0040] Table 1 shows the wheelbase for different vehicle types. The obstacle height range is, for example, 120-200mm, and the tire lift height must cover the obstacle. Taking a Type A vehicle with an obstacle height of 160mm as an example, the wheelbase of a Type A vehicle is, for example, 2500mm, according to the formula... The target angle of inclination is calculated. ;in, The height of the obstacle. This refers to the wheelbase.

[0041] Table 1 Wheelbase for different vehicle types

[0042] By adjusting the tilt angle, the front or bottom of the battery pack is directly exposed to the impact path of the barrier structure 4, avoiding the obstruction of the vehicle's front-end protection device or subframe. This ensures that the test can effectively assess the battery pack's anti-scratch performance and solves the problem that traditional horizontal scrape tests cannot expose the real risks.

[0043] The barrier structure 4 is positioned directly in front of the test rig's travel path to simulate protruding obstacles on the road surface, such as stones, curb edges, and steps. The barrier structure 4 is, for example, a spherical barrier with a radius of, for example, 75mm, and made of, for example, 45# steel. The spherical barrier structure can simulate impact scenarios involving the arc or sharp edges of obstacles. Furthermore, the height of the barrier structure 4 needs to be dynamically adjusted according to the test rig's tilt angle and the battery pack's impact position, with the adjustment error controlled within 0-4mm to ensure the impact point accurately corresponds to the test target area. The lateral deviation between the centerline of the barrier structure 4 and the battery pack's impact point must be ≤±25mm to avoid distortion of test results due to positioning misalignment. At least 5 meters of track in front of the barrier structure 4 must be kept level, flat, and dry. Simultaneously, the bottom of the barrier structure 4 must be fixed to a level and hard test surface to ensure no displacement of the barrier structure 4 during impact.

[0044] The control components include at least a data acquisition module 17 and a processing module 16. The data acquisition module 17 is used to acquire the target angle and target test speed before the test, and at the same time, it acquires the motion parameters of the test trolley, which include at least the current position and speed. The processing module 16 sends instructions to the test trolley based on the data acquired by the data acquisition module 17, instructing the test trolley to travel towards and collide with the barrier structure 4 at the target speed and the target test speed, ensuring that the test process conforms to the standardized working conditions, that is, after the impact, the battery pack needs to scrape from the front end to the rear end, simulating a complete bottom scraping process.

[0045] This application utilizes the collaborative operation of angle adjustment and control components to accurately simulate actual vehicle undercarriage scraping scenarios and achieve test controllability. Specifically, using a test trolley as the basic carrier, the battery pack mounting components at the bottom of the trolley have adjustable installation space, accommodating different battery pack specifications without frequent trolley replacements, thus improving equipment versatility. The connection design between the trolley frame 1 and the suspension components, combined with the lifting structure 2 and the first handwheel 3 of the angle adjustment component, allows manual application of force to move the telescopic part, thereby adjusting the tilt angle between the battery pack and the road surface. The target tilt angle is locked with fastening bolts, ensuring accurate and stable test angles. This avoids the problem in traditional horizontal undercarriage scraping tests where the battery pack cannot contact the obstacle due to vehicle protective devices or bounce, effectively reproducing non-horizontal undercarriage scraping scenarios such as vehicles straddling curbs. Simultaneously, the obstacle structure 4 at the front can simulate various road obstacles. Combined with the control components that communicate with the test trolley, it can accurately control the trolley to complete the impact at the target angle and target test speed, ensuring the standardization and controllability of the test process. The device is easy to operate and highly adaptable. It not only solves the problem that existing tests are unable to expose real safety risks, but also provides test conditions that are more in line with actual working conditions for the safety performance evaluation of battery pack scraping. It significantly improves the accuracy and reference value of test results and helps to optimize the safety design of electric vehicle battery packs.

[0046] Furthermore, the device also includes at least one set of counterweight components disposed on the trolley frame 1; like Figure 1 As shown, the counterweight assembly includes: The counterweight bracket 7 is slidably connected to the trolley frame 1; the counterweight bracket 7 is equipped with a counterweight block. An adjustment structure is provided on the trolley frame 1. The adjustment structure has an adjustment part and a connecting part, and the connecting part is rotatably connected to the counterweight bracket 7. The force applied by the adjustment part drives the connecting part to rotate, so that the counterweight bracket 7 and the counterweight block move along the trolley frame 1 to the target position.

[0047] The counterweight component adjusts the total mass of the test trolley equipped with the battery pack to match the reference mass of the target vehicle by adding or removing counterweight blocks. Furthermore, by adjusting the position of the counterweight blocks, the front and rear axle load distribution of the test trolley is optimized to ensure that the center of gravity position and axle load ratio of the trolley match the real vehicle during the test. This avoids distortion of the undercarriage test posture due to mass or axle load deviations, such as excessive forward / backward tilting of the trolley during an impact, which does not match the actual undercarriage scraping scenario.

[0048] Specifically, the counterweight bracket 7 is a tray-type frame structure with M10 threaded holes at the top. Bolts can be used to connect the counterweight blocks to these holes. For example, the weight of a single counterweight block is 40 kg. The counterweight bracket 7 is slidably connected to the trolley frame 1 via a linear guide rail slider structure. Linear guide rails are laid on the trolley frame 1 along the travel direction. Matching sliders are installed at the bottom of the counterweight bracket 7, embedding within the linear guide rails and sliding freely along them. This connection method ensures smooth movement of the counterweight bracket 7 while limiting its lateral (perpendicular to the travel direction) displacement, ensuring that the counterweight blocks always move longitudinally along the frame during adjustment, precisely changing the front and rear axle loads. Here, for example, there are four counterweight brackets 7, and by moving the positions of these four counterweight brackets 7, a symmetrical and uniform arrangement is formed, facilitating even weight distribution and preventing the trolley's center of gravity from shifting to one side.

[0049] The adjustment section of the adjustment structure is the component for the operator to input force, such as an adjustment handwheel. The central shaft of the adjustment handwheel is rigidly connected to the lead screw (or screw rod), and the operator can input rotational force by rotating the handwheel.

[0050] The connecting part of the adjustment structure is a component that transmits power, such as a lead screw and nut or a connecting rod structure. If it is a lead screw and nut structure, the connecting part is the nut that matches the lead screw. The nut and the counterweight bracket 7 are rotatably connected by a pin or bearing, allowing a small rotation between the nut and the counterweight bracket 7 when the nut rotates with the lead screw to avoid jamming. If it is a connecting rod structure, the connecting part is a connecting rod with one end fixed to the rotating shaft driven by the adjustment handwheel and the other end rotatably connected to the bracket. The rotation of the rotating shaft drives the connecting rod to swing, pushing the bracket to move.

[0051] The rotating connection between the connecting part (nut / linkage rod) and the counterweight bracket 7 is, for example, by using a pin to pass through the ear plate of the nut and the counterweight bracket 7. This connection method can eliminate the jamming problem caused by manufacturing errors during the adjustment process. When the adjusting part drives the connecting part to move, the connecting part can rotate slightly around the rotation point to ensure that the power is smoothly transmitted to the counterweight bracket 7 and drive it to slide along the linear guide rail.

[0052] When adjusting the counterweight, the connecting bolts between the counterweight bracket 7 and the trolley frame 1 must first be loosened. The counterweight bracket 7 has fixing plates on both sides or at the bottom that connect to the trolley frame 1. These fixing plates have elongated grooves along the travel direction and are fixed to the trolley frame 1 with bolts. After loosening these bolts, the counterweight bracket 7 is only constrained by the adjustment structure and limited by the linear guide rail, allowing it to move freely longitudinally along the trolley frame 1, providing sufficient space for position adjustment. The operator applies rotational force through the adjustment section, and the power is transmitted to the counterweight bracket 7 through the connecting section, causing the counterweight bracket 7 to move. During adjustment, the current position of the counterweight bracket 7 can be read through the scale lines on the trolley frame 1 until it reaches the target position that matches the axle load distribution of the target vehicle model. For example, if the front axle load of the target vehicle model accounts for 45%, then part of the counterweight bracket 7 needs to be adjusted forward to bring the front axle load of the test trolley to that proportion. Once the counterweight bracket 7 has moved to the target position, stop the force adjustment and immediately tighten the connecting bolts. The bolts pass through the elongated groove of the fixing plate and the threaded hole of the frame. After tightening, the counterweight bracket 7 can be fixed in the current position to prevent the counterweight bracket 7 from sliding due to vibration during the test impact, ensuring the stability of the counterweight position and axle load distribution, and ensuring the accuracy of the test data.

[0053] By adding or removing counterweights and adjusting their positions, the total mass, front-to-rear axle load ratio, and center of gravity of the test vehicle can be made completely consistent with the target vehicle model. For example, if the reference mass of the actual vehicle is 1500kg, when simulating a Class A vehicle (wheelbase 2500-2700mm, front axle load ratio 48%), counterweights can be added first to make the total weight of the test vehicle reach 1500kg, and then the position of the counterweight bracket 7 can be adjusted to make the front axle load reach 720kg (1500kg×48%). This ensures that the posture of the test vehicle is consistent with that of the actual vehicle during the bottoming-out impact, avoiding the distortion problem that the battery pack does not scrape the barrier in the test, but the actual vehicle will scrape it due to axle load deviation.

[0054] Furthermore, the control components also include: The contact triggering unit 8 is located at the rear end of the trolley frame 1 and is used to send a trigger signal to the brake control unit 10 when the test trolley is subjected to physical collision or pressure. The status monitoring unit 9 is used to generate test status information based on the pressure of the braking system, the battery charge and the motion status parameters of the test trolley; The brake control unit 10 is electrically connected to the brake system actuator of the test trolley. When the test status information meets the preset status conditions, it generates a braking command based on the trigger signal and sends it to the brake system actuator. The braking command is used to instruct the brake system to perform braking operation.

[0055] It should be noted that the contact trigger unit 8 generates a braking trigger signal by directly sensing physical collisions or pressure. The contact trigger unit 8 is located at the rear end of the trolley frame 1, which is the area most prone to accidental collisions, such as when the trolley slides beyond the predetermined range after the test and collides with the site equipment, or when other auxiliary devices accidentally touch the rear end of the trolley. Placing the contact trigger unit 8 at the rear end can cover the risk scenarios to the greatest extent. The contact trigger unit 8 is, for example, a limit switch or a push-button contact switch, with its trigger end (contact) protruding from the rear end surface of the trolley frame 1 and able to directly contact external collision objects. When the rear end of the test trolley is subjected to physical collisions (such as hitting a wall or equipment) or pressure (such as being squeezed by other components), the external force will push the contact of the contact trigger unit 8 to move, causing the internal circuit of the switch to conduct or disconnect, generating a trigger signal, which is sent to the braking control unit 10 in real time.

[0056] The braking system pressure refers to the pressure of the air tank in the trolley's braking system. The standard pressure requirement is that the air pressure in the braking system's air tank 20 is ≥0.6 Mbar. Battery charge refers to the battery charge of the braking control system (such as the power supply to the solenoid valves and control units). The standard charge requirement is ≥20%. The motion parameters of the test trolley include at least the trolley's real-time speed and traction acceleration. The standard speed requirement is a speed control accuracy of ±0.2 km / h, and the standard acceleration requirement is a traction acceleration ≤0.3g. The status monitoring unit 9 monitors the braking system pressure, battery charge, and the test trolley's motion parameters to constitute the test status information.

[0057] The preset state conditions refer to the state conditions that meet the above-mentioned standard requirements. If all conditions are met, the brake control unit 10 generates a braking command based on the trigger signal. If any standard requirement is not met, no command is generated. The brake control unit 10 sends the braking command to the brake system actuator, and the brake system actuator performs the braking operation according to the braking command. Figure 5 As shown, a specific braking operation involves energizing the solenoid valve 19 to open the air circuit. High-pressure gas in the air tank 20 pushes the cylinder 18, causing the brake pads to clamp the wheel, thus braking the test vehicle. After the test vehicle stops moving, the operator can also send a release command to the brake control unit 10 using a remote switch. The brake control unit 10 generates a release command to instruct the solenoid valve 19 of the brake system actuator to de-energize, close the air circuit, and reset the brake pads. Here, the air pressure gauge 21 of the brake system actuator monitors the air circuit pressure value in real time and sends the pressure value to the brake control unit 10. When the pressure value reaches the preset pressure value, the brake control unit 10 sends a stop inflation command to the brake system actuator, instructing the cylinder 18 to stop inflation. At this pressure value, the brake pads can clamp the wheel. The preset pressure value is set according to the actual situation.

[0058] Furthermore, the device also includes a detection component that is communicatively connected to the control component; like Figure 4 As shown, the detection component includes: Wheel load cell module 11 is used to collect the mass of the test trolley. Image acquisition module 12 is used to acquire deformation images of the battery pack during the test; Temperature detection unit 13 is used to collect temperature data of the battery pack after the test. Battery pack insulation testing unit 14 is used to test the insulation performance of the battery pack after the test. Smoke monitoring unit 15, which is used to detect the smoke emitted by the battery pack after the test; The processing module 16 is used to determine whether to issue an abnormal alarm message based on the temperature data of the battery pack after the test, the insulation performance of the battery pack after the test, and the smoke situation of the battery pack after the test. The processing module 16 is also used to determine the damage location of the battery pack and the transmission path of the impact force based on the deformation image of the battery pack during the test.

[0059] It should be noted that the type of wheel load meter module 11 is, for example, a wheel load sensor, and the quantity is, for example, four. The four wheel load sensors are respectively set for the four wheels of the test trolley and installed in the area where the corresponding wheel contacts the ground. When the test trolley travels over the wheel load sensor, the wheel load sensor can sense the pressure of the wheel on the ground through the pressure strain gauge, calculate the load of a single wheel based on the pressure, and add the four loads to obtain the total mass of the trolley.

[0060] The image acquisition module 12 is, for example, a high-speed camera with a minimum resolution of, for example, 1280×720. Multiple such cameras can be deployed on the side, front, and road surface of the test vehicle. During the test vehicle's impact with the barrier structure 4 at the target speed, the high-speed cameras capture real-time dynamic images of the battery pack contacting, being squeezed, and scraped against the barrier structure 4. After the test, the processing module 16 replays the dynamic images to determine the location of damage to the battery pack and the transmission path of the impact force. Based on the determination results, the structural strength design of the battery pack is optimized. For example, taking two high-speed cameras as an example, the positions and requirements of the two high-speed cameras are shown in Table 2. The shooting positions in Table 2 are as follows... Figure 7 As shown in Table 3, the photos taken before and after the test cover the minimum number and location of photos that should be taken before and after the test. "0" in Table 3 indicates that a photo should be taken and sent to the processing module 16 for later analysis of the battery pack's design strength.

[0061] Table 2 Camera Locations and Requirements

[0062] Table 3. Experimental photographs

[0063] The temperature detection unit 13 can be a distributed temperature sensor, such as a thermocouple or an infrared thermometer. The distributed temperature sensor can be attached to the surface of the battery pack casing and to the corresponding collision contact area and the position of the cell module to detect the temperature data of the battery pack in real time.

[0064] The battery pack insulation testing unit 14 is, for example, an insulation resistance tester. After the test is completed, a DC high voltage is applied between the positive and negative terminals of the battery pack and the casing, and the insulation resistance value is measured using the insulation resistance tester.

[0065] The smoke detection unit 15 can be, for example, a photoelectric smoke sensor or an ionization smoke sensor. The smoke sensor can be arranged in a closed test space around the battery pack. When the battery pack is damaged by scratches and there is electrolyte leakage or short circuit of the battery cell, smoke may be generated. The smoke sensor detects the smoke concentration.

[0066] The processing module 16 receives temperature data from the temperature detection unit 13, insulation resistance value from the battery pack insulation detection unit 14, and alarm signal from the smoke detection unit 15. If the temperature, insulation resistance value, or smoke concentration exceeds the corresponding set abnormal value, the battery pack is determined to be in an abnormal state and an abnormal alarm message is issued. The set abnormal value is configured according to actual needs.

[0067] like Figure 9 As shown, this application provides a battery pack scratch test method, implemented based on the aforementioned battery pack scratch test apparatus. The method includes the following steps: S100. When the test data of the test trolley is adjusted to be the same as the actual vehicle data of the target vehicle, the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle are obtained.

[0068] The process of adjusting the test data of the test vehicle to match the actual vehicle data of the target model includes the following steps: Install the battery pack in the mounting space of the battery pack mounting assembly and obtain test data from the test trolley; the test data should include at least the initial mass, initial front and rear axle loads, and initial wheelbase. Obtain real-vehicle data for the target vehicle model; the target vehicle model is the type of vehicle using the current battery pack. Based on the actual vehicle data, initial mass, initial front and rear axle loads, and initial wheelbase of the target vehicle model, determine the mass difference, axle load difference, and wheelbase difference; Adjust the counterweights and their relative positions according to the mass difference and axle load difference, and adjust the wheelbase of the test trolley according to the wheelbase difference, until the test data of the test trolley is adjusted to be the same as the actual data of the target model.

[0069] Here, the vehicle's mass, axle load distribution, and wheelbase are key parameters affecting the undercarriage scraping test attitude. Mass determines the kinetic energy during impact, axle load distribution affects the vehicle's tilting tendency, and wheelbase is related to the calculation of the tilt angle after tire lift. By adjusting the parameters of the test vehicle to be the same as those of the actual vehicle, it is ensured that the undercarriage scraping test can accurately reflect the battery pack's undercarriage scraping performance. Specifically, the battery pack to be tested is installed in the installation space of the battery pack mounting assembly. The wheel load meter module 11 is used to collect the initial total mass, initial front axle load, and initial rear axle load of the test vehicle with the battery pack installed, and obtain the actual vehicle data of the target model. For example, the actual total mass of an A0 class car is 1500kg, the front axle load is 720kg, the rear axle load is 780kg, and the wheelbase is 2400mm. Based on these data, the mass difference, axle load difference, and wheelbase difference are calculated. The number of counterweights is increased or decreased according to the mass difference, the front and rear positions of the counterweight bracket 7 are adjusted according to the axle load difference, and the wheelbase is adjusted according to the wheelbase difference until the total mass, front and rear axle loads, and wheelbase of the test vehicle are completely consistent with the parameters of the target model.

[0070] The target vehicle models mentioned above refer to the mass-produced vehicles to which the currently tested battery packs are compatible. The actual vehicle data for the target models can be obtained from the vehicle's manufacturer's technical manual or through actual vehicle measurements.

[0071] The first height of the road obstacle mentioned above refers to the protrusion height of the obstacle in a real-world scenario, i.e., the obstacle height, such as the average height of a curb stone being 160mm; the tire radius of the target vehicle refers to the radius of the actual vehicle's tires, such as the radius of a 175 / 65R14 tire being approximately 304mm; such as Figure 6 As shown, the wheelbase of the target vehicle model refers to the distance between the centers of the front and rear axles of the actual vehicle. Figure 6 In this context, D stands for battery pack.

[0072] S200: Based on the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle, calculate the target angle between the battery pack and the road surface, and adjust the tilt angle formed between the battery pack and the road surface to the target angle through the angle adjustment component.

[0073] The target angle between the battery pack and the road surface is calculated based on the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle. This calculation includes the following steps: The difference between the first height of the road obstacle and the tire radius of the target vehicle is taken as the distance the tires of the target vehicle are lifted. The target angle is the quotient of the distance the tires of the target vehicle are lifted divided by the wheelbase of the target vehicle.

[0074] It's important to note that in real-world scenarios, when a vehicle encounters an obstacle, the front wheels contact the obstacle first and are lifted, causing the front of the vehicle to tilt upwards, creating an angle with the ground. This angle directly determines the relative position of the battery pack bottom to the obstacle. If the angle is too small, the battery pack may be obstructed by the vehicle chassis (such as the subframe or protective beams), preventing it from contacting the obstacle; if the angle is too large, it may exceed the reasonable range for real-world scenarios, leading to experimental distortion. Therefore, this step simulates the tilting process of a real vehicle by using the ratio of tire lift distance to wheelbase.

[0075] Specifically, the distance the tire is lifted is equal to the difference between the initial height of the road obstacle and the tire radius of the target vehicle, where the initial height refers to the height of the obstacle. For example... Figure 8 As shown, when the tire presses onto an obstacle, the height of the contact point between the tire and the obstacle determines the basis for the vehicle's lifting. If the obstacle height h is less than the tire radius r, the tire only partially presses onto the obstacle, and the lifting distance is a positive value, i.e., the absolute value of hr. If the obstacle is too high, i.e., h ≥ r, the tire may completely ride on the obstacle, and the lifting distance is hr. In this case, the angle may exceed the reasonable range and needs to be adjusted in conjunction with the test device's maximum tilt angle limit of ≤3°. The target angle is obtained by dividing the tire lifting distance of the target vehicle by the wheelbase of the target vehicle. When the front wheel is lifted, the tilt angle is directly proportional to the lifting distance. Here, the tilt angle range is, for example, less than or equal to 3°. The radian value of this angle is approximately equal to the tangent value and the sine value, and can be directly approximated by a ratio.

[0076] For example, if the obstacle height h = 160mm and the tire radius r = 307mm, then the tire is lifted a distance of 160 - 307 = -147mm. Here, the negative sign indicates that the lifting direction is upward, and the absolute value of 147mm is used in the actual calculation; if the wheelbase L = 2600mm, then... (Radians), converted to target angle ≈ 3.24°; since the maximum tilt angle of the test device is limited to 3°, 3° is finally taken as the target angle.

[0077] The angle obtained through the above calculations is adjusted to the tilt angle between the battery pack and the road surface to simulate the actual tilt posture of the vehicle when passing through obstacles, ensuring that the bottom of the battery pack can contact the obstacle and prevent it from being blocked by the subframe, protective devices, etc.

[0078] S300. Select the target impact point on the barrier structure 4, and obtain the second height between the target impact point and the driving surface, as well as the radius of the spherical region of the barrier structure 4.

[0079] Based on the battery pack design drawings or disassembly observation, weak areas of the battery pack are selected as impact points, such as module connections, high-voltage wiring harnesses, and the bottom center where the casing strength is lower. This ensures that real safety risks are exposed during testing, avoiding impacts on the more robust edge areas. These selected impact points serve as the target impact points on barrier structure 4. The second height between the target impact point and the road surface refers to the vertical distance from the target impact point to the ground; the radius of the spherical region of barrier structure 4 is, for example, 75 mm.

[0080] The second height between the target impact point and the road surface and the radius of the spherical region of barrier structure 4 are obtained, for example, by measuring with a ruler.

[0081] S400. Based on the target angle, the second height between the target impact point and the road surface, and the radius of the spherical region of the barrier structure 4, the third height of the highest point of the barrier structure 4 from the road surface is calculated.

[0082] The third altitude is calculated using the following formula: ; in, The third highest altitude, The second highest altitude, Let be the radius of the spherical region of barrier structure 4. The target angle is the tilt angle.

[0083] Here, as Figure 8 As shown, m is the target impact point, and k is the straight-line distance between the target impact point and the center of the spherical region of the spherical barrier structure. It is used to assist in calculating the height difference between the highest point of the barrier structure 4 and the impact point.

[0084] When barrier structure 4 collides with the battery pack, the center of the spherical region, the target impact point, and the ground must satisfy the condition that the line connecting the center of the spherical region to the target impact point is perpendicular to the bottom surface of the battery pack.

[0085] S500, adjust the height of the highest point of the barrier structure 4 above the road surface to the third height, and position the barrier structure 4 in front of the test vehicle's travel path.

[0086] Adjust the height of the highest point of the spherical barrier above the ground to the third height, and calibrate it with a measuring tape or laser rangefinder to ensure that the error is ≤4mm.

[0087] Position the barrier structure 4 laterally and longitudinally so that it is directly in front of the test trolley's travel path. Ensure that when the test trolley travels at the target angle, the battery pack can completely scrape the barrier from front to back. Adjust the left and right positions of the barrier structure 4 so that the lateral deviation between the center line of its spherical area and the target impact point of the battery pack is ≤ ±25mm. Prevent the impact point from shifting to a non-target area. The position of the barrier structure 4 can be marked with chalk or positioning stakes to prevent displacement during the test.

[0088] S600 controls the test trolley to run at the target test speed and impact the barrier structure 4 at the target angle until the battery pack scrapes from its front end to its rear end to complete the test.

[0089] Here, the braking system and image acquisition module 12 are activated. The braking system is configured with the brake power on, the air pressure in the air tank 20 ≥ 0.6 Mbar, the brake fluid level normal, and the battery fully charged. For the image acquisition modules 12, one module captures images of the area of ​​the battery pack that may be deformed, while the other module captures images covering the entire test vehicle. The target test speed is determined based on the actual vehicle scenario, for example, using the actual urban road speed of 30 km / h as the target test speed. Here, the speed control accuracy is, for example, ±0.2 km / h.

[0090] The processing module 16 sends a traction command to the traction system of the test trolley to instruct the traction system to start and drive the test trolley to accelerate to the target test speed with an acceleration of ≤0.3g, while maintaining the target tilt angle along the travel path. When the front end of the test trolley approaches the barrier structure 4, the battery pack and the target impact point of the barrier structure 4 make contact first. As the test trolley continues to move forward, the battery pack gradually scrapes the barrier from the front end to the rear end, thereby simulating the entire process of a real vehicle riding over an obstacle and continuously scraping the bottom. After the rear end of the battery pack has finished scraping, the control component sends a trigger signal to the braking control unit 10 through the contact trigger unit 8 or manual remote control by the operator, so that the brake system actuator can be activated to bring the test trolley to a smooth stop, and the test is completed.

[0091] By simulating the tilt angle scenario of a vehicle riding over an obstacle, the problem of not hitting the battery pack when scraping the bottom in traditional horizontal scenarios is solved, thus recreating a real bottom scraping accident. Furthermore, there are quantitative standards for everything from test trolley data, tilt angle, obstacle height to impact speed, ensuring that the test is repeatable and the data is comparable.

[0092] Furthermore, this method also includes the following steps: After the experiment was completed, temperature data from multiple points on the battery pack were obtained to obtain a temperature set; If the number of temperature data points in the temperature set that exceed the temperature threshold is greater than a preset number, then a temperature anomaly message will be generated. Obtain the insulation resistance value between the positive and negative electrodes of the battery pack and its housing. If the insulation resistance value is less than or equal to the insulation threshold, generate insulation abnormality information; Obtain the smoke concentration value of the battery pack. If the smoke concentration value is greater than the concentration threshold, generate smoke abnormality information.

[0093] It should be noted that the temperature data of multiple points of the battery pack are collected first to form a temperature set to monitor the precursor of thermal runaway.

[0094] Temperature is the first warning signal for the safety of the battery pack. Short circuits of battery cells and leakage of electrolyte will both be accompanied by abnormal temperature rise. When arranging the points, the high-risk areas and evenly distributed areas of the battery pack need to be covered. For example, for the direct contact area of the battery pack during collision, one point is set at the front, middle, and rear of the bottom of the battery pack where it rubs against the wall barrier. For the densely packed area of the battery cells in the battery pack, one point is set at the left middle and right middle positions of the internal module of the battery pack. For the weak area at the edge of the battery pack, one point is set at the left front and right front corners of the battery pack. Immediately start the temperature detection unit 13 after the test, continuously collect temperature data at a sampling frequency of 10Hz, and the monitoring duration is defaulted to 24h, 72h or 240h, which can be set according to actual needs. The real-time temperature data of all points are summarized to form a temperature set, such as {25°C, 26°C, 58°C, 27°C, 25°C, 28°C, 26°C}.

[0095] By comparing the temperature data with the temperature threshold, judge whether there is local abnormal temperature rise. For example, overheating at a single point may be a short circuit of the battery cell, and overheating at multiple points may be overall thermal runaway. Here, the temperature threshold can be set according to the type of battery pack. For example, the temperature threshold of a ternary lithium battery is set to 50°C, and the temperature threshold of a lithium iron phosphate battery is set to 60°C. The preset quantity can be set according to the total number of points. For example, when there are 7 points in total, the preset quantity is set to 1, that is, as long as 1 point exceeds the threshold, it is judged as abnormal and temperature abnormality information is generated to prompt the tester that the battery pack has a risk of thermal runaway.

[0096] Bottom scraping impact may cause damage to the housing and tearing of the internal insulation layer, resulting in electric leakage. Test through the battery pack insulation detection unit 14. Connect the high-voltage harnesses of the battery pack insulation detection unit 14 to the positive electrode, negative electrode and housing of the battery pack respectively, ensure reliable contact and avoid virtual connection. Apply a DC high voltage between the positive and negative electrodes and the housing. For example, when the rated voltage of the battery pack is 300V, apply a 500V high voltage, which complies with the GB / T18384.3 standard, measure the leakage current in the circuit, and calculate the insulation resistance value according to insulation resistance = applied voltage / leakage current. The insulation threshold is, for example, 100Ω / V; if the insulation resistance value > the insulation threshold, it is judged that the insulation performance is qualified; if the insulation resistance value ≤ the insulation threshold, generate insulation abnormality information to prompt the existence of high-voltage electric leakage risk and immediately cut off the power to avoid electric shock to personnel.

[0097] For example, smoke concentration can be collected by evenly distributing smoke sensors 30-50cm above the battery pack to form a three-dimensional monitoring network, avoiding any missed areas. The sampling frequency is synchronized with temperature detection, for example, 10Hz, and the smoke concentration value (unit: mg / m³) is output in real time. The concentration threshold is, for example, 0.5mg / m³. If the smoke concentration value exceeds the concentration threshold, an abnormal smoke information is generated to prompt the test personnel to immediately initiate emergency measures such as fire extinguishing and ventilation.

[0098] Temperature data, insulation resistance values, and smoke concentration values ​​are all stored by the processing module 16 and can be exported to generate reports, providing specific guidance for battery pack design optimization.

[0099] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A battery pack bottom scraping test device, characterized in that, include: The test trolley includes a trolley frame (1), and a battery pack mounting assembly is provided at the bottom of the trolley frame (1). The battery pack mounting assembly has an adjustable mounting space for mounting the battery pack. The bottom of the trolley frame (1) is connected to the trolley wheels through a suspension assembly. An angle adjustment assembly includes: a lifting structure (2) disposed on the trolley frame (1), one end of the lifting structure (2) is provided with a first handwheel (3), and the other end forms a telescopic part for abutting against the suspension assembly; the lifting structure (2) is driven to move by the first handwheel (3), thereby moving the telescopic part and raising or lowering the front of the trolley frame (1), thereby changing the tilt angle formed between the battery pack installed on the battery pack mounting assembly and the road surface, and locking the current tilt angle by fastening bolts when the tilt angle is the target angle; Barrier structure (4), the barrier structure (4) is set in front of the test trolley to simulate road obstacles; A control component is communicatively connected to the test trolley, and the control component is at least used to control the test trolley to collide with the barrier structure (4) at a target angle and a target test speed.

2. The battery pack scraping test device according to claim 1, characterized in that, The battery pack mounting assembly includes: Multiple battery pack mounting units are disposed at the bottom of the trolley frame (1) and arranged along the traveling direction of the trolley frame (1); each battery pack mounting unit includes at least: Mounting beam (5) is provided at the bottom of the trolley frame (1) and the mounting beam (5) is arranged along the traveling direction of the trolley frame (1); the mounting beam (5) is provided with multiple mounting holes; Two adapters (6) are connected to the mounting holes; The mounting space is formed between the adapters (6) of all the battery pack mounting units for mounting the battery pack.

3. The battery pack scraping test device according to claim 1, characterized in that, Also includes: At least one set of counterweight components is installed on the trolley frame (1); The counterweight assembly includes: A counterweight bracket (7) is slidably connected to the trolley frame (1); a counterweight block is provided on the counterweight bracket (7); An adjustment structure is provided on the trolley frame (1). The adjustment structure has an adjustment part and a connecting part, and the connecting part is rotatably connected to the counterweight bracket (7). The force applied by the adjustment part drives the connecting part to rotate, so that the counterweight bracket (7) and the counterweight block move along the trolley frame (1) to the target position.

4. The battery pack scraping test device according to claim 1, characterized in that, The control component includes: Data acquisition module (17), the data acquisition module (17) is used to acquire the target angle and the target test speed; The processing module (16) is used to control the test trolley to collide with the barrier structure (4) at the target angle and the target test speed.

5. The battery pack scraping test device according to claim 1, characterized in that, The control component also includes: Contact trigger unit (8), which is located at the rear end of the trolley frame (1) and is used to send a trigger signal to the brake control unit (10) when the test trolley is subjected to physical collision or pressure; The status monitoring unit (9) is used to generate test status information based on the pressure of the braking system, the battery charge and the motion status parameters of the test trolley; Braking control unit (10), which is electrically connected to the brake system actuator of the test trolley, is used to generate a braking command and send it to the brake system actuator according to the trigger signal when the test state information meets the preset state conditions; the braking command is used to instruct the brake system to perform braking operation.

6. The battery pack scraping test device according to claim 4, characterized in that, Also includes: The detection component is communicatively connected to the control component; The detection component includes: Wheel load meter module (11), the wheel load meter module (11) is used to collect the mass of the test trolley; Image acquisition module (12), the image acquisition module (12) is used to acquire the deformation image of the battery pack during the test; Temperature detection unit (13), the temperature detection unit (13) is used to collect temperature data of the battery pack after the test; Battery pack insulation testing unit (14), the battery pack insulation testing unit (14) is used to test the insulation performance of the battery pack after the test; Smoke monitoring unit (15), the smoke monitoring unit (15) is used to detect the smoke emission of the battery pack after the test; The processing module (16) is used to determine whether to issue an abnormal alarm message based on the temperature data of the battery pack after the test, the insulation performance of the battery pack after the test, and the smoke situation of the battery pack after the test. The processing module (16) is also used to determine the damage location and the transmission path of the impact force of the battery pack based on the deformation image of the battery pack during the test.

7. A method for testing the bottom of a battery pack, characterized in that, Based on the battery pack scraping test apparatus according to any one of claims 1-6, the method includes the following steps: When the test data of the test trolley is adjusted to be the same as the actual vehicle data of the target model, the first height of the road obstacle, the tire radius of the target model and the wheelbase of the target model are obtained. Based on the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle, the target angle between the battery pack and the road surface is calculated, and the tilt angle formed between the battery pack and the road surface is adjusted to the target angle by the angle adjustment component. Select a target impact point on the barrier structure (4), and obtain the second height between the target impact point and the driving surface, as well as the radius of the spherical region of the barrier structure (4); Based on the target angle, the second height between the target impact point and the road surface, and the radius of the spherical region of the barrier structure (4), the third height of the highest point of the barrier structure (4) from the road surface is calculated. The height of the highest point of the barrier structure (4) above the road surface is adjusted to the third height, and the barrier structure (4) is positioned in front of the travel path of the test vehicle; The test trolley is controlled to run at the target test speed and collide with the barrier structure (4) at the target angle until the battery pack scrapes from its front end to its rear end to complete the test.

8. The battery pack scraping test method according to claim 7, characterized in that, Based on the first height of the road obstacle, the tire radius of the target vehicle, and the wheelbase of the target vehicle, the target angle between the battery pack and the road surface is calculated, specifically including the following steps: The difference between the first height of the road obstacle and the tire radius of the target vehicle is taken as the distance by which the tires of the target vehicle are lifted. The target angle is the quotient of the distance the tires of the target vehicle are lifted by dividing the wheelbase of the target vehicle.

9. A battery pack scraping test method according to claim 7, characterized in that, The test data of the test vehicle is adjusted to be the same as the actual vehicle data of the target model. This includes the following steps: The battery pack is installed in the mounting space of the battery pack mounting assembly, and the test data of the test trolley is obtained; the test data includes at least the initial mass, initial front and rear axle loads, and initial wheelbase; Obtain real vehicle data for the target vehicle model; the target vehicle model refers to the type of vehicle using the current battery pack. Based on the actual vehicle data of the target vehicle model, the initial mass, the initial front and rear axle loads, and the initial wheelbase, determine the mass difference, axle load difference, and wheelbase difference; According to the mass difference and the axle load difference, the counterweights and their relative positions are increased or decreased, and the wheelbase of the trolley is adjusted according to the wheelbase difference until the test data of the test trolley is adjusted to be the same as the actual vehicle data of the target model.

10. A battery pack scraping test method according to claim 7, characterized in that, The method further includes the following steps: After the experiment was completed, temperature data from multiple points on the battery pack were obtained to obtain a temperature set; If the number of temperature data in the temperature set that exceeds the temperature threshold is greater than a preset number, then temperature anomaly information is generated; Obtain the insulation resistance value between the positive and negative terminals of the battery pack and its casing. If the insulation resistance value is less than or equal to the insulation threshold, generate insulation anomaly information. Obtain the smoke concentration value of the battery pack. If the smoke concentration value is greater than the concentration threshold, generate smoke anomaly information.

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