Battery loading curve test tool, equipment and method

Abstract

The invention provides a tool, equipment and a method for testing a load curve of a battery. The battery load curve test tool comprises a vertical lifting and restraining mechanism which comprises a top plate and a bottom plate, and the top plate has a vertical lifting degree of freedom relative to the bottom plate; the horizontal limiting and restraining mechanism comprises a limiting groove, the limiting groove is provided with an upward opening, the limiting groove can contain a battery, and the depth direction of the limiting groove is perpendicular to the thickness direction of the contained battery; the pressing head is located on the face, facing the bottom plate, of the top plate, and the pressing head can make contact with one side of the battery and impacts and / or extrudes the battery; wherein the contact surface of the pressure head and the battery is a convex curved surface, the rotation generatrix corresponding to the convex curved surface is a line segment, and the line segment is parallel to the thickness direction of the battery. Therefore, one side of the battery is impacted or extruded by using the pressure head, so that blunt impact possibly encountered when the battery is installed in a new energy automobile can be conveniently and accurately simulated.

Description

Technical Field

[0001] The present application relates to the field of battery testing, and in particular to a test tool, equipment and method for a battery load curve. Background Art

[0002] In recent years, new energy vehicles have developed rapidly. Among the batteries used in new energy, lithium-ion batteries have the advantages of high energy density, long cycle life, and high charging efficiency. They are widely used in the power battery systems of pure electric vehicles or hybrid vehicles. Since lithium-ion power batteries are generally installed at the bottom of the car, when a traffic accident occurs, lithium-ion batteries are easily squeezed or impacted. If lithium-ion batteries are abused, there will be a higher risk of fire and explosion. Therefore, a mature lithium-ion battery usually undergoes testing under a variety of mechanical abuse conditions before it can be used in new energy vehicles.

[0003] Common lithium-ion batteries include cylindrical batteries, soft-pack batteries, square-shell batteries, blade batteries and other forms. Different battery types have different forms of constraints on the battery cells. At the same time, different OEMs also have significant differences in the layout of batteries, such as using modular battery modules or directly using battery cells. These different layout forms have led to the diversity and complexity of the constraints.

[0004] In traffic accidents, lithium-ion batteries of new energy vehicles are often faced with dynamic impact conditions. Due to the structural characteristics of the battery pack, the battery is mainly subjected to blunt surface impact. This impact condition poses a severe challenge to the safety and stability of the battery. Different types of batteries are arranged and fixed in different ways in the battery pack, resulting in differences in the restraint form of the battery. These differences significantly affect the response characteristics of the battery under mechanical impact. Therefore, it is necessary to conduct dynamic blunt surface impact tests on lithium-ion batteries under different restraint forms to evaluate their safety performance and stability under various actual working conditions, thereby providing important support for battery pack design optimization and reducing the risk of personal and property damage in traffic accidents.

[0005] The Chinese invention patent application with publication number "CN115265993A" discloses "A battery pack flying carpet side column collision test method and test system". The test system installation includes a column collision device with a collision column installed on a fixed barrier, a mobile trolley with wheels on which the battery pack is installed, and a mobile flying carpet for carrying the mobile trolley arranged on a traction track. The mobile flying carpet can run on the traction track and make the battery pack collide with the collision column. The working conditions of the side column collision of the flying carpet of the battery pack of a pure new energy vehicle can be simulated to the greatest extent, so as to better examine the protection performance of the battery pack against external intrusion. However, the collision test system is established in an environment that imitates the size of a real car, and is a collision test of the entire battery pack.

[0006] The Chinese utility model patent with announcement number "CN203772999U" discloses "a short-circuit test fixture for lithium batteries". The test fixture includes a fixture body, which is a rectangular frame with one side open. A battery positioning mechanism is arranged on the bottom plate of the fixture body, and a short-circuit mechanism is arranged on the top plate. The battery positioning mechanism includes a left positioning seat and a right positioning seat arranged relatively. The short-circuit mechanism is composed of a short-circuit metal module, a cylinder, and thermal insulation ceramics. The short-circuit metal module and the thermal insulation ceramics are controlled by the cylinder to move up and down. Although the test fixture is small in size, it mainly relies on a movable short-circuit metal module to perform a short-circuit test on the positive and negative poles of the battery, and is not a test on the battery's extrusion load.

[0007] Some existing fixtures and tools cannot change the constraint form of the battery, or cannot perform dynamic blunt impact tests on the battery. In the actual battery accident state, lithium-ion batteries are usually faced with dynamic impact conditions in the in-plane direction, and their constraints are also affected by the battery type and the internal structure of the battery pack. In addition, due to the influence of the structure around the battery, the battery is mostly subjected to blunt impact in the in-plane direction. The efficacy of lithium-ion batteries is affected by the loading speed, constraints and impact surface. Existing battery test fixtures cannot perform dynamic blunt impact tests on batteries for different constraints, so it is difficult to accurately simulate and test the mechanical response of the battery in a real collision accident. This limitation makes the current testing method insufficient to fully evaluate the mechanical safety issues faced by batteries in actual use. Summary of the invention

[0008] This application is made in view of the above-mentioned state of the prior art. This application aims to solve or alleviate at least one of the above-mentioned problems.

[0009] In the first aspect, the present application provides a test fixture for a battery load curve, comprising: a vertical lifting and restraining mechanism, the vertical lifting and restraining mechanism comprising a top plate and a bottom plate, the top plate having a vertical lifting freedom relative to the bottom plate; a horizontal limiting and restraining mechanism, the horizontal limiting and restraining mechanism comprising a limiting groove, the limiting groove having an upward opening, the limiting groove being able to accommodate a battery, the depth direction of the limiting groove being perpendicular to the thickness direction of the accommodated battery; a pressure head, the pressure head being located on a side of the top plate facing the bottom plate, the pressure head being able to contact one side of the battery and impact and / or squeeze the battery; wherein the contact surface between the pressure head and the battery is a convex surface, the rotation generatrix corresponding to the convex surface is a line segment, and the line segment is parallel to the thickness direction of the battery. As a further improvement of the present application, the two ends of the pressure head are end planes, the end planes intersect the convex surface vertically, the shape of the end planes is arched, the distance between the two end planes is not less than the thickness of the battery, and the opening width of the limit groove is not less than the distance between the two end planes; the opening width of the limit groove can be changed and realize horizontal clamping constraint on the battery.

[0010] As a further improvement of the present application, the shape of the end plane is a minor arc or a semicircle, the top of the pressure head has a top plane, the top plane is in surface contact with the top plate, the top plate has a through mounting hole, and the mounting hole is detachably assembled with the top plane of the pressure head through a fastener.

[0011] As a further improvement of the present application, the top plate and the bottom plate are movably assembled via a plurality of guide pillars, and the guide pillars pass through the top plate.

[0012] As a further improvement of the present application, a pair of mirror-symmetrical clamping members are mounted on the bottom plate, the pair of clamping members are connected by a plurality of bolts, and the pair of clamping members can accommodate or clamp and restrain the battery.

[0013] As a further improvement of the present application, the clamping plate comprises a horizontal plate and a vertical plate which are perpendicular to each other, the horizontal plate forms a surface contact with the bottom plate, the bolts pass through the vertical plate, and a plurality of the bolts are symmetrically distributed on both sides of the test fixture; the limit groove is the space relatively surrounded by the vertical plate and the bolts.

[0014] As a further improvement of the present application, the bolt includes a screw section, and the screw section is equipped with a nut; a sleeve is also sleeved on the screw section, and both ends of the sleeve are in contact with the facing surfaces of the vertical plates of a pair of the clamping plate members.

[0015] As a further improvement of the present application, the horizontal plate and the vertical plate in the same clamping plate are vertically fixed with ribs.

[0016] In a second aspect, a battery load curve testing device is provided, comprising: a temperature sensor and a voltage sensor, wherein the temperature sensor is arranged on the battery, and the voltage sensor is electrically connected to the battery.

[0017] According to a third aspect, a method for testing a battery load curve is provided, comprising: step S1: lifting the top plate by a lifting device; step S2: placing the battery in the limiting groove, selecting a sleeve with an appropriate axial length according to the thickness of the battery, the sleeve passing through the bolt, and the bolt connecting a pair of clamping parts; step S3: releasing the top plate at an acceleration less than that of a free fall, and falling on the side of the battery by the self-weight of the top plate; step S4: applying a static load until the battery voltage drops sharply and a short circuit occurs; or applying a dynamic impact to impact the battery, wherein the starting point height of the dynamic impact is adjustable, and the load of the dynamic impact is adjustable.

[0018] The beneficial effects of the test fixture for the battery load curve of the present application include: providing a simple and reliable fixture that can test single batteries. The pressure head is used to impact or squeeze one side of the battery, so that the test personnel can study the deformation of the battery under load. First, the top plate drives the pressure head to rise and fall, so that the pressure head can apply force to the battery; the top plate is convenient for direct contact with the power source, and then the force is transmitted to the pressure head, and the pressure head directly applies force to the battery. Secondly, the limit groove wraps the battery to prevent the battery from running off when loaded, and the limit groove can also provide a reaction force. Finally, the side of the pressure head that contacts the battery is a revolving surface, which is also a convex surface. This makes the pressure head and the battery in line contact when they first contact, and with further impact or squeezing, the contact between the pressure head and the battery becomes a surface contact. This facilitates accurate simulation of the blunt impact that the battery may encounter when installed in a new energy vehicle. At different positions of the battery, the force form received by the battery is also similar, which facilitates the control of irrelevant variables and facilitates subsequent evaluation of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a three-dimensional diagram of an embodiment of a test fixture for a battery load curve of the present application;

[0021] Figure 2It is a front view of an embodiment of a test fixture for a battery load curve of the present application;

[0022] Figure 3 It is a right view of an embodiment of a test fixture for a battery load curve of the present application;

[0023] Figure 4 yes Figure 3 AA cross-sectional view of the test fixture for the battery load curve;

[0024] Figure 5 It is a three-dimensional diagram of an embodiment of the battery load curve test fixture of the present application in which the top plate and the pressure head are hidden;

[0025] Figure 6 It is a schematic diagram of the assembly of a top plate and a pressure head according to an embodiment of the present application;

[0026] Figure 7 is a perspective view of an embodiment of a battery of the present application;

[0027] Figure 8 (a) is a schematic diagram of a contact state between the pressure head and the battery of the present application;

[0028] Figure 8 (b) is a schematic diagram of another contact state between the indenter and the battery of the present application;

[0029] Fig. 9 It is a schematic diagram of the assembly of the bolt and the sleeve of the present application;

[0030] Fig.10 It is a relationship diagram between the constraint load of the bolt and the sleeve and the expansion displacement of the battery in the present application.

[0031] Description of Reference Numerals

[0032] 1-bottom plate; 2-guide column; 3-top plate; 31-mounting hole; 4-clamping piece; 41-horizontal plate; 42-vertical plate; 5-rib plate; 6-pressing head; 61-convex curved surface; 62-end plane; 7-bolt; 71-expanded head; 72-screw segment; 8-nut; 9-sleeve; 10-battery; 101-terminal; 11-limiting groove. DETAILED DESCRIPTION

[0033] The exemplary embodiments of the present application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present application, and are not intended to exhaust all possible methods of the present application, nor to limit the scope of the present application.

[0034] The following is a further detailed description of the battery load curve testing tool, battery load curve testing equipment, and battery load curve testing method of the present application in conjunction with specific embodiments.

[0035] See also Figure 1 and Figure 5 The embodiment of the present application provides a test fixture for a battery load curve. The test fixture may include a vertical lifting and restraining mechanism, a horizontal limit and restraining mechanism, and a pressure head 6. The vertical lifting and restraining mechanism includes a top plate 3 and a bottom plate 1, and the top plate 3 has a vertical lifting freedom relative to the bottom plate 1. Figure 5 As shown, the horizontal limit and restraint mechanism has a limit groove 11, and the limit groove 11 has an upward opening. The limit groove 11 can accommodate the battery 10, and the depth direction of the limit groove 11 is perpendicular to the thickness direction of the battery 10 accommodated in the limit groove 11. The pressure head 6 is located on the side of the top plate 3 facing the bottom plate 1, and the pressure head 6 can contact one side of the battery 10 and implement impact or compression. Figure 6 As shown, the contact surface between the pressure head 6 and the battery 10 is a convex surface 61 , which is a revolved surface. The revolving generatrix of the convex surface 61 is a line segment, which is parallel to the thickness direction of the battery 10 .

[0036] In this way, the battery load curve test fixture of the present application has both vertical constraint capability and horizontal constraint capability. The vertical constraint mainly allows the battery 10 to achieve impact or extrusion deformation, while the horizontal constraint can mainly adapt to batteries 10 of different specifications, and is also convenient for associating the horizontal expansion deformation of the battery 10 caused by the extrusion deformation caused by the vertical constraint.

[0037] The battery can be a lithium-ion battery. The battery 10 is generally loaded in two directions, namely, the battery cover direction and the battery side direction. Figure 8 (a) and Figure 8 As shown in (b), the pressure head 6 is in contact with the battery 10, and the busbars of the convex surface 61 are parallel to the thickness direction of the battery 10. More precisely, Figure 8 (a) The pressure head 6 is in contact with the cover plate of the battery 10, Figure 8 (b) The pressure head 6 contacts the side of the battery 10, Figure 8 (a) compared to battery 10 Figure 8 The battery 10 in (b) is rotated 90°.

[0038] Considering that when a single battery 10 is placed inside a battery pack, both sides of the battery 10 are restrained by other structures (such as mica sheets, circular frames and other batteries 10). In a real collision accident, the load curve in the in-plane direction of the battery 10 includes the influence of the constraint conditions. Therefore, when testing the in-plane load curve of the lithium-ion battery 10, it is necessary to perform personalized constraints on both sides of the battery 10 to obtain the mechanical response of the battery 10 under different constraint conditions.

[0039] In the direction of placement of the mainstream battery pack, when the vehicle is hit from the side, the loading direction is the in-plane direction of the single battery 10. No matter what kind of load is applied during the external collision, it is transmitted to the single battery 10 through the beam on the vehicle body, which is equivalent to a blunt impact. Therefore, the contact surface between the indenter 6 and the battery 10 is simulated by a convex surface 61. And, as Figure 8 As shown in (b), the convex surface 61 is in contact with the side of the battery 10 in the initial state.

[0040] In one embodiment, if Figure 6 As shown, the two ends of the pressing head 6 are end planes 62, the end planes 62 intersect the convex curved surface 61 vertically, and the shape of the end planes 62 is an arcuate or semicircular shape. The distance between the two end planes 62 (i.e., the thickness of the pressing head 6) is not less than the thickness of the battery 10, and the opening width of the limiting groove 11 is not less than the distance between the two end planes 62. With further squeezing of the battery 10, the pressing head 6 can penetrate into the limiting groove 11. The opening width of the limiting groove 11 can be greater than or equal to the thickness of the pressing head 6.

[0041] For a single battery 10 in a group of batteries 10 , it is constrained by the batteries 10 on both sides, and the loading of the battery by the pressure head 6 only needs to be as large as the thickness of one single battery 10 .

[0042] In one embodiment, the shape of the end plane 62 is a minor arc or a semicircle, and the top of the pressure head 6 has a top plane, and the top plane is in surface contact with the top plate 3. Figure 4 As shown, the top plate 3 has a through mounting hole 31, and the mounting hole 31 is detachably assembled with the top plane of the pressure head 6 through a fastener. The mounting hole 31 can be stepped, and the top of the fastener in the mounting hole 31 is not higher than the opening of the mounting hole 31, so that the top plate 3 provides a complete plane to withstand impact or extrusion. When impacting, the pressure head 6 can perform a blunt impact on the battery 10.

[0043] The shape of the pressure head 6 is also for the convenience of processing and after finite element calculation, so it adopts an arcuate shape, that is, a part of a disc shape.

[0044] The radius corresponding to the convex surface 61 of the pressure head 6 may be 90 mm.

[0045] In one embodiment, the top plate 3 and the bottom plate 1 are movably assembled via a plurality of guide posts 2, and the guide posts 2 pass through the top plate 3. Optionally, the top plate 3 may be provided with guide sleeves for the guide posts 2 to pass through.

[0046] The number of guide posts 2 may be four. The guide sleeve may include or be a linear motion bearing. The movable assembly of the guide sleeve and the guide post 2 makes the friction resistance between the guide sleeve and the guide post 2 small, thereby ensuring the smooth lifting of the top plate 3. The guide post 2 and the guide sleeve also play a role of precise guidance, ensuring that the top plate 3 is lifted and lowered in the vertical direction.

[0047] In one embodiment, the upper surface of the top plate 3 contacts a hydraulic press or a drop hammer.

[0048] The hydraulic press can achieve static loading, while the drop hammer can achieve dynamic impact. The maximum equivalent weight of the hydraulic press is about tens of tons.

[0049] A guide rail may also be provided in the falling path of the drop hammer to ensure that the drop hammer impacts the center of the top plate without deviation.

[0050] In one embodiment, a pair of mirror-symmetrical clamping plates 4 are mounted on the bottom plate 1, and the pair of clamping plates 4 are connected by a plurality of bolts 7, and the pair of clamping plates 4 can accommodate batteries 10. The clamping plates 4 are similar to angle steel structures.

[0051] The clamping plate 4 can be made of high-strength steel so that it is not easily deformed by the expanded battery 10 .

[0052] In one embodiment, if Figure 1 As shown, the clamping plate 4 includes a horizontal plate 41 and a vertical plate 42. The horizontal plate 41 forms a surface contact with the bottom plate 1. The bolts 7 pass through the vertical plate 42. The bolts 7 are symmetrically distributed on both sides of the battery 10. The limit groove 11 is a space relatively surrounded by the vertical plate 4 and the bolts 7. The connecting line of the bolts 7 on the same side of the battery 10 is located on the same vertical line and is arranged at equal intervals. Figure 2 or Figure 4 As shown, the number of bolts 7 may be six.

[0053] The inner wall of the limiting groove 11 is not provided with a buffer layer, so that most of the impact or extrusion energy of the pressure head 6 can be absorbed by the battery 10. Adding a buffer layer will destroy the simple boundary conditions of the limiting groove 11, which is not conducive to model verification.

[0054] The inner wall of the limiting groove 11 is mainly composed of the facing surfaces of the vertical plate 42 , and the horizontal plate 41 is used for fixing and supporting the bottom plate 1 .

[0055] In one embodiment, the horizontal plate 41 may be provided with a waist-shaped hole (not shown in the figure), and a fastener is inserted into the waist-shaped hole to assemble the horizontal plate 41 with the bottom plate 1. The length direction of the waist-shaped hole is parallel to the length direction of the bolt 7. This allows the position of the clamping member 4 on the bottom plate 1 to be fine-tuned when necessary, thereby changing the actual opening width of the limiting groove 11.

[0056] In one embodiment, if Fig. 9 As shown, the bolt 7 includes an enlarged head 71 and a screw section 72 which are connected in one piece. The screw section 72 passes through the vertical plates 42 of the pair of clamping members 4. The screw section 72 is equipped with a nut 8. The nut 8 and the enlarged head 71 are in contact with the opposite back surfaces of the vertical plates 42 of the pair of clamping members 4. The screw section 72 is also covered with a sleeve 9. The two ends of the sleeve 9 are in contact with the opposite surfaces of the vertical plates 42 of the pair of clamping members 4. Fig. 9 As shown, in order to facilitate the internal structure, Fig. 9 The sleeve 9 in the figure is cut in half longitudinally.

[0057] The nut 8 plays a role in controlling the constraints, such as Fig. 9 As shown, the initial distance between the two vertical plates 42 is controlled by a customized sleeve 9, and during the experiment, only the nut 8 needs to be tightened. Fig.10 As shown, Fig.10 The figure is a diagram showing the relationship between the constraint load of the bolt and the sleeve and the battery expansion displacement. When the battery 10 is not squeezed by the pressure head 6, the sleeve 9 is generally subjected to axial compression. That is, after the nut 8 is turned, the two vertical plates 42 squeeze the sleeve 9 towards each other, which constrains the battery 10 in the horizontal direction, and the horizontal constraint capacity of the battery 10 is determined according to the actual degree of rotation of the nut 8, that is, the actual horizontal constraint capacity of the battery 10 is multiple and adjustable. When the battery 10 is squeezed by the pressure head 6 and expands laterally, when the initial expansion is small, such as Fig.10 As shown in the left half of the relationship line, the sleeve 9 is still subjected to the inward extrusion force. When the battery 10 contacts the vertical plate 42, it continues to expand, as shown in FIG. Fig.10 As shown in the right half of the relationship line, the two vertical plates 42 relax the compression of the sleeve 9, and the external inward constraint on the battery 10 depends on the size and material of the bolt 7. The constraint stiffness of the battery 10 can be controlled by customizing different bolts 7. The combination of the two can control the constraint conditions. The nut 8 determines the widest limit position of the horizontal limit and constraint mechanism, and the sleeve 9 determines the narrowest limit position of the horizontal limit and constraint mechanism.

[0058] During the compression test of the battery 10 by the pressure head 6, the bolt 7 is only subjected to tension but not compression. The axial length of the sleeve 9 is determined according to the specific needs such as the thickness of the battery 10. The axial length of the sleeve 9 can be selected to be equal to or slightly greater than the thickness of the battery 10, and can be selected to be 2 mm greater than the thickness of the battery 10.

[0059] When testing batteries 10 of different thickness specifications, sleeves 9 of different axial lengths are replaced according to the thickness of the battery 10. In addition, since the pressure head 6 and the top plate 3 are also detachable, a new pressure head 6 can also be replaced, and the distance between the end planes 62 at both ends of the new pressure head 6 is different to adapt to the new battery 10.

[0060] In one embodiment, a rope such as a steel cable may be connected between the vertical plates 42 of a pair of clamping members 4, and the tension of the rope may be used to limit the maximum limit spacing between the two vertical plates 42.

[0061] In one embodiment, if Figure 1 As shown, the horizontal plate 41 and the vertical plate 42 in the same clamping plate 4 are vertically fixed with the rib plate 5. The rib plate 5, the horizontal plate 41 and the vertical plate 42 are vertical to each other in space, and the rib plate 5 and the horizontal plate 41 or the vertical plate 42 can be welded and fixed. Each horizontal plate 41 or vertical plate 42 can be fixed with multiple rib plates 5. The rib plates 5 of the same clamping plate 4 are arranged at equal intervals.

[0062] The battery load curve test fixture of the present application is simple and ingenious in that it improves the repeatability and credibility of the in-plane compression test of the battery 10, which is conducive to model verification. It can solve the practical problem of inconsistent in-plane load curve test standards for the battery 10, and can simulate the rationality of real load as much as possible, and can provide simple boundary conditions for the battery 10.

[0063] The present application also provides a battery load curve test device. It adds a temperature sensor and a voltage sensor on the basis of the battery load curve test tool. The temperature sensor can be attached to the outer wall of the battery 10, and the voltage sensor can be electrically connected to the battery 10. Figure 7 As shown, the battery 10 has an electrically connectable terminal 101. The temperature sensor is used to sense whether the temperature of the battery 10 exceeds a normal value in a deformed state. The voltage sensor is used to sense whether the voltage of the battery 10 exceeds a normal value in a deformed state.

[0064] The present application also provides a test method for the battery load curve. It includes: step S1: using a testing machine (i.e., a lifting mechanism for a drop hammer impact or a quasi-static hydraulic testing machine) to lift the top plate 3 and the pressure head 6 together. When it is necessary to lift the top plate 3 and the pressure head 6 together, the top plate 3 can be tied to the moving end of the testing machine with the help of a strap, so that the moving end of the testing machine can also lift the top plate 3 and the pressure head 6 when it rises. Step S2: Place the single battery 10 between the two clamping plates 4, then select the sleeve 9, and fix the two clamping plates 4 with bolts 7, and place the entire limit groove 11 directly below the pressure head 6. Step S3: Slowly relax the top plate 3 and the pressure head 6, so that the top plate 3 and the pressure head 6 fall on the side of the battery 10 by their own gravity. Step S4: Apply quasi-static loading conditions to the top plate 3 until the voltage of the battery 10 drops sharply and a short circuit occurs, then the experiment ends. Or apply a dynamic impact to the top plate 3 to impact the battery 10. The height of the starting point of the drop hammer and the weight of the drop hammer are adjustable. Among them, the placement of the battery 10 is in front, and the installation of the sleeve 9, the bolt 7 and the clamping plate 4 is in the back. If the installation of the sleeve 9, the bolt 7 and the clamping plate 4 is in the front, and the placement of the battery 10 is in the back, the battery 10 must be placed from the top opening of the limit groove 11, which requires the pressure head 6 to be lifted to a higher level. This will cause the length of the corresponding guide column 2 to be lengthened, and the stability between the bottom plate 3, the guide column 2, and the top plate 3 may also be deteriorated.

[0065] This method tests a single battery 10, not a whole battery pack. During the test phase, the top plate 3 may be in contact with the battery 10, and the impact object may impact the top plate 3, and the impact force is transmitted to the battery 10 through the top plate 3 and the pressure head 6 in sequence.

[0066] After the impact test on the battery 10 is completed, due to the deformation of the battery 10, all the bolts 7 can be removed, so that the limit groove 11 is not only opened at the top, but also opened on both sides of the limit groove 11, which makes it convenient for the tester to take out the battery 10. One of the purposes of the battery load curve test tool and battery load curve test equipment of the present application is to facilitate the long-term and repeated testing of the battery load curve test method.

[0067] The above embodiments are only for illustrating the technical concept and features of the present application, and their purpose is to enable people familiar with this technology to understand the content of the present application and implement it. They cannot be used to limit the scope of protection of the present application. All equivalent changes or modifications made according to the spirit of the present application should be included in the scope of protection of the present application.

Claims

1. A battery load curve test tool, characterized in that: include: A vertical lifting and restraining mechanism, the vertical lifting and restraining mechanism comprising a top plate (3) and a bottom plate (1), the top plate (3) having a vertical lifting freedom relative to the bottom plate (1); A horizontal limiting and restraining mechanism, the horizontal limiting and restraining mechanism comprising a limiting groove (11), the limiting groove (11) having an upward opening, the limiting groove (11) being capable of accommodating a battery (10), the depth direction of the limiting groove (11) being perpendicular to the thickness direction of the accommodated battery (10); A pressure head (6), the pressure head (6) being located on a side of the top plate (3) facing the bottom plate (1), the pressure head (6) being capable of contacting one side of the battery (10) and impacting and / or squeezing the battery (10); The contact surface between the pressure head (6) and the battery (10) is a convex surface (61), the generatrix of revolution corresponding to the convex surface (61) is a line segment, and the line segment is parallel to the thickness direction of the battery (10).

2. The battery load curve testing tool according to claim 1, characterized in that: The two ends of the pressure head (6) are end planes (62), the end planes (62) intersect the convex curved surface (61) at right angles, the shape of the end planes (62) is an arch, the distance between the two end planes (62) is not less than the thickness of the battery (10), and the opening width of the limiting groove (11) is not less than the distance between the two end planes (62); The opening width of the limiting groove (11) can be changed and can achieve horizontal clamping constraints on the battery (10).

3. The battery load curve testing tool according to claim 2, characterized in that: The end plane (62) is in the shape of a minor arc or a semicircle, the top of the pressure head (6) is provided with a top plane, the top plane is in surface contact with the top plate (3), the top plate (3) is provided with a through mounting hole (31), and the mounting hole (31) is detachably assembled with the top plane of the pressure head (6) by means of a fastener; The pressure head (6) is capable of performing a blunt impact on the battery (10).

4. The battery load curve testing tool according to claim 1, characterized in that: The top plate (3) and the bottom plate (1) are movably assembled via a plurality of guide pillars (2), and the guide pillars (2) pass through the top plate (3).

5. The battery load curve testing tool according to claim 1, characterized in that: A pair of mirror-symmetrical clamping members (4) are mounted on the bottom plate (1); the pair of clamping members (4) are connected by a plurality of bolts (7); and the pair of clamping members (4) can accommodate or clamp and constrain the battery (10).

6. The battery load curve testing tool according to claim 5, characterized in that: The clamping plate (4) comprises a horizontal plate (41) and a vertical plate (42) which intersect each other vertically, the horizontal plate (41) forms surface contact with the bottom plate (1), the bolts (7) pass through the vertical plate (42), and a plurality of the bolts (7) are symmetrically distributed on both sides of the test fixture; The limiting groove (11) is a space relatively surrounded by the vertical plate (4) and the bolt (7).

7. The battery load curve testing tool according to claim 5, characterized in that: The bolt (7) comprises a screw segment (72), and the screw segment (72) is equipped with a nut (8); The screw section (72) is also covered with a sleeve (9), and both ends of the sleeve (9) are in contact with the facing surfaces of the vertical plates (42) of the pair of clamping plate members (4).

8. The battery load curve testing tool according to claim 6, characterized in that: The horizontal plate (41) and the vertical plate (42) in the same clamping plate member (4) are vertically fixed with ribs (5) together.

9. A battery load curve testing device, characterized in that: A test fixture for a battery load curve comprising any one of claims 1 to 8, wherein the test fixture for a battery load curve further comprises a temperature sensor and a voltage sensor, wherein the temperature sensor is arranged on the battery (10), and the voltage sensor is electrically connected to the battery (10).

10. A method for testing a battery load curve, characterized in that: The battery load curve testing tool according to claim 7 is used, and the battery load curve testing method includes: Step S1: using a lifting device to lift the top plate (3); Step S2: placing the battery (10) in the limiting groove (11), selecting the sleeve (9) with a suitable axial length according to the thickness of the battery (10), the sleeve (9) passing through the bolt (7), and the bolt (7) connecting a pair of the clamping plate members (4); Step S3: releasing the top plate (3) at an acceleration less than that of a free fall, and allowing the top plate (3) to fall onto the side of the battery (10) by its own weight; Step S4: applying static loading until the voltage of the battery (10) drops suddenly and a short circuit occurs; or applying dynamic impact to impact the battery (10), wherein the height of the descending starting point of the dynamic impact is adjustable, and the load of the dynamic impact is adjustable.

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