Test device

Abstract

This application relates to a testing device, comprising: a test cylinder having a through hole extending along a first direction; an electrode post movably inserted into the through hole, the test cylinder and the electrode post together forming a test area for accommodating a battery; at least one adaptive part and at least one first pressure plate, the adaptive part being disposed at the end of any of the electrode posts facing the test area, and the first pressure plate covering the side of the corresponding adaptive part facing the test area; the adaptive part is capable of adjusting its thickness along the first direction according to the pressure of the electrode post, so that the first pressure plate is perpendicular to the first direction. The testing device according to an embodiment of this application has the advantage of high test result accuracy.

Description

Technical Field

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

[0002] Solid-state batteries are currently recognized as an important direction for the next generation of secondary power sources, and are expected to significantly improve the energy density of power batteries and energy storage power sources. During the testing pressure and electrode material transfer process of solid-state batteries, uneven stress caused by uneven bottom and tilting inevitably damages the structure, morphology and composition of the solid-state battery, resulting in large testing errors and low accuracy of test results. Utility Model Content

[0003] Therefore, it is necessary to provide a testing device to address the problem of low accuracy in test results.

[0004] A first aspect of this application provides a testing apparatus, comprising: a test cylinder having a through hole extending along a first direction; electrode posts movably inserted into the through hole, the test cylinder and two electrode posts together forming a test area for accommodating a battery; at least one adaptive part and at least one first pressure plate, the adaptive part being disposed at the end of the electrode post facing the test area, and the first pressure plate covering the side of the corresponding adaptive part facing the test area; the adaptive part being capable of adjusting its thickness along the first direction according to the pressure of the electrode post, such that the first pressure plate is perpendicular to the first direction.

[0005] By setting an adaptive unit and a first pressure plate, when the bottom of the electrode post is uneven or tilted, the adaptive unit can adjust its thickness along the first direction based on the pressure of the electrode post, so that the surface of the first pressure plate can remain perpendicular to the first direction. In this way, the first pressure plate is not affected by the direction of force applied by the electrode post. The first pressure plate can transmit pressure to the battery, making the battery powder more uniformly stressed, thereby avoiding damage to the battery's structure, morphology, and composition during the test, resulting in small test errors and high test accuracy.

[0006] In one embodiment, the first pressure plate can be electrically connected to the corresponding electrode post through the adaptive portion. Thus, the adaptive portion fills the space between the electrode post and the first pressure plate, serving as the electrical connection medium between the first pressure plate and the electrode post, achieving synergistic optimization of pressure conduction and current. Furthermore, the testing device does not require a separate electrical connection structure, simplifying the structure and facilitating battery testing.

[0007] In one embodiment, there are two adaptive units and two first pressure plates. The surfaces of both first pressure plates are perpendicular to the first direction. The adaptive units are respectively disposed on the ends of the two electrode posts facing the test area, and the first pressure plates cover the corresponding adaptive units. Thus, the two adaptive units ensure that the surfaces of the two first pressure plates are not affected by the bottom of the electrode posts. The upper and lower electrode posts are each connected to their corresponding first pressure plates through an adaptive unit, and the two first pressure plates transmit pressure to both ends of the battery. The first pressure plates maintain a direction perpendicular to the first direction, ensuring that both ends of the battery are subjected to uniform force. This avoids damage to the battery's structure, morphology, and composition during testing, resulting in small test errors and high test accuracy.

[0008] In one embodiment, the testing apparatus further includes a second pressure plate. The adaptive portion is disposed on the end of one of the electrode posts facing the test area, and the first pressure plate covers the adaptive portion. The second pressure plate covers the end of the other electrode post facing the test area. Thus, the second pressure plate can cover the lower end of the electrode post facing the test area, and the electrode post transmits pressure to the lower end of the battery through the second pressure plate. By applying force with the entire plate, the powder at the lower end of the battery is subjected to more uniform force.

[0009] In one embodiment, the adaptive unit includes a plurality of metal spheres, all of which fill the space between the electrode post and the first pressure plate. Thus, when the bottom of the electrode post is uneven or tilted, each metal sphere displaces and deforms based on the morphology of its contact surface with the electrode post, dynamically filling the unevenness and gaps between the electrode post end face and the first pressure plate. This ensures that the surface of the first pressure plate is not affected by the bottom of the electrode post. During the process of the electrode post transmitting pressure to the battery through the first pressure plate, the first pressure plate maintains a direction perpendicular to the first direction, ensuring uniform force on the battery. Furthermore, a continuous low-impedance conductive path can be formed between the electrode post and the first pressure plate, providing a high-precision, highly repeatable electrical contact environment for battery testing.

[0010] In one embodiment, the metal sphere is made of copper, stainless steel, or aluminum alloy; and / or, the diameter of the metal sphere is 10µm to 90µm.

[0011] In one embodiment, the adaptive section includes a conductive paste and a plurality of filler spheres, all of which fill the space between the electrode post and the first pressure plate. The electrode post and the first pressure plate are electrically connected through the conductive paste. Thus, through the composite structure design of the conductive paste and filler spheres, a stable three-dimensional conductive network is constructed while achieving dynamic pressure adaptation between the electrode post and the pressure plate.

[0012] In one embodiment, the conductive paste includes conductive silver paste; and / or, the filling microspheres are made of copper, stainless steel, aluminum alloy, rubber or silicone; and / or, the diameter of the filling microspheres is 30µm to 250µm.

[0013] In one embodiment, the adaptive unit includes a plurality of elastic microspheres, each of which is coated with a conductive layer. All the elastic microspheres fill the space between the electrode post and the first pressure plate. Thus, when the bottom of the electrode post is uneven or tilted, each elastic microsphere displaces and deforms based on the morphology of its contact surface with the electrode post, dynamically filling the unevenness and gaps between the electrode post end face and the first pressure plate. This ensures that the surface of the first pressure plate is not affected by the bottom of the electrode post. During the process of the electrode post transmitting pressure to the battery through the first pressure plate, the first pressure plate maintains a direction perpendicular to the first direction, ensuring uniform force distribution on the battery.

[0014] In one embodiment, the conductive layer is one of a conductive carbon layer, a copper plating layer, an aluminum plating layer, and a silver plating layer; and / or, the thickness of the conductive layer is 1µm to 10µm; and / or, the elastic sphere is made of rubber or silicone; and / or, the diameter of the elastic sphere is 30µm to 250µm.

[0015] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a test apparatus provided in some embodiments of this application.

[0017] Figure 2 This is a schematic diagram of the structure of a test apparatus provided in some other embodiments of this application.

[0018] Figure 3 This is a schematic diagram of the structure of a test apparatus provided in some embodiments of this application.

[0019] Figure 4 This is a schematic diagram of the battery structure provided in some embodiments of this application.

[0020] Figure 5 This is a flowchart illustrating a battery detection method provided in some embodiments of this application.

[0021] Explanation of reference numerals in the attached figures:

[0022] Test cylinder-10, through hole-11, test area-12, electrode post-20, adaptive part-40, metal ball-41, conductive paste-42, filling ball-43, elastic ball-44, first pressure plate-50, second pressure plate-60, battery-90, solid electrolyte-91, positive electrode material-92, negative electrode material-93. Detailed Implementation

[0023] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0025] In the description of the embodiments of this application, if the technical terms such as "first" and "second" appear, these terms are used only for descriptive purposes to distinguish different objects, and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0026] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0027] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0028] In the description of the embodiments of this application, if the term "multiple" appears, "multiple" means at least two (including two), such as two, three, etc., unless otherwise explicitly specified. Similarly, if the term "multiple sets" appears, "multiple sets" refers to two or more sets (including two sets), and if the term "multiple pieces" appears, "multiple pieces" refers to two or more pieces (including two pieces).

[0029] In the description of the embodiments of this application, if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0030] In the description of the embodiments of this application, unless otherwise explicitly specified and limited, the technical terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0031] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0032] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0033] Currently, the application of power batteries is becoming increasingly widespread in the market. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. With the continuous expansion of power battery applications, market demand is also constantly increasing. Among these, solid-state batteries are currently recognized as an important direction for the next generation of secondary power sources, and are expected to significantly improve the energy density and intrinsic safety of power batteries and energy storage power sources. In traditional liquid-ion batteries, the electrode / electrolyte interface exhibits good solid / liquid contact due to the wetting effect of the electrolyte. In solid-state batteries, due to the use of solid electrolytes, the electrode / electrolyte interface transforms into a solid / solid contact, inevitably leading to significant interfacial contact losses, resulting in impaired carrier transport at the electrode / electrolyte interface. To ensure stable cycling of solid-state batteries, a large stacking pressure is usually applied externally to mitigate the interfacial contact losses caused by the solid / solid contact. However, large external pressures can not only cause the positive electrode active material to break under pressure, but also cause creep in common metal negative electrodes, leading to a short-circuit risk in the battery. Therefore, quantitatively analyzing the dependence of external pressure on the porosity, contact area, tortuosity, and creep of the metal anode in solid-state batteries is crucial for assessing their impact on the electrochemical performance of solid-state batteries and for developing next-generation high-energy-density solid-state batteries. CT imaging, using CT scans as one of the detection methods for solid-state batteries, features non-destructive testing and three-dimensional visualization. CT scans mainly utilize the principle of X-ray attenuation after passing through matter: X-rays emitted from a radiation source attenuate to varying degrees as they penetrate materials of different thicknesses and densities. Different amounts of X-rays, received at the detector, generate electrical signals of different frequencies, corresponding to images of varying brightness on the screen. These images are then processed by a computer to form a visualized image.

[0034] In related technologies, high-energy, high-throughput CT detection can achieve non-destructive, real-time, and high-precision three-dimensional observation of the structure and morphology of electrode materials. Currently, a common testing method is to apply appropriate test pressure to solid-state batteries to complete the test. However, due to unevenness or tilting of the electrode posts at the bottom of the testing device, the solid-state battery experiences uneven stress, inevitably damaging the sample's structure, morphology, and composition, resulting in large errors and low accuracy of the test results.

[0035] To alleviate the problem of low test accuracy, an adaptive part and a pressure plate can be designed for the test device. The adaptive part can adjust its own thickness based on external pressure to ensure that the pressure plate is not affected by the direction of force applied by the electrode post. The pressure plate can transmit pressure to the solid-state battery, making the powder of the solid-state battery more uniformly stressed. This avoids damage to the structure, morphology and composition of the solid-state battery during the test, resulting in small test errors and high test accuracy.

[0036] Figure 1 This is a schematic diagram of the structure of a test apparatus provided in some embodiments of this application. Figure 2 This is a schematic diagram of the structure of a test apparatus provided in some other embodiments of this application. Figure 3 This is a schematic diagram of the structure of a test apparatus provided in some embodiments of this application. Figure 4 This is a schematic diagram of the battery structure provided in some embodiments of this application.

[0037] See Figures 1 to 4 As shown, a first aspect of this application provides a testing apparatus for testing a battery 90.

[0038] The testing apparatus includes a test cylinder 10, two electrode posts 20, an adaptive section 40, and a first pressure plate 50. The test cylinder 10 has a through hole 11 extending along a first direction X. The electrode posts 20 are movably inserted into the through hole 11. The test cylinder 10 and the two electrode posts 20 together form a test area 12 for accommodating a battery 90. The adaptive section 40 is disposed at the end of the electrode post 20 facing the test area 12, and the first pressure plate 50 covers the side of the adaptive section 40 facing the test area 12. The adaptive section 40 can adjust its thickness along the first direction X according to the pressure of the electrode post 20, so that the first pressure plate 50 is perpendicular to the first direction X.

[0039] The test cylinder 10 has a through hole 11 extending along the first direction X; in this embodiment, the first direction X is a vertical direction, combined with Figures 1 to 4 As shown, the test cylinder 10 can be in a vertical position, with the first direction X being the axial direction of the test cylinder 10 itself; the through hole 11 forms openings at the top and bottom of the test cylinder 10 respectively, and the electrode post 20 is inserted into the opening along the first direction X.

[0040] The adaptive section 40 can be disposed at the end of any electrode post 20 facing the test area 12, and the first pressure plate 50 covers the side of the adaptive section 40 facing the test area 12. The first pressure plate 50 can be used to contact and press against the battery 90, and the pressure on the electrode post 20 is transmitted to the battery 90 through the first pressure plate 50, which facilitates the measurement of the battery 90.

[0041] It is important to understand that the adaptive part 40 can adjust its thickness along the first direction X based on the pressure of the electrode post 20. This means that the adaptive part 40 can deform under pressure, thereby changing its shape, and under the constraint of the sidewall of the through hole 11, changing the thickness of each region of the adaptive part 40 along the first direction X. Specifically, when the bottom end of the electrode post 20 is flat, the thickness of each region of the adaptive part 40 can be the same under the extrusion pressure of the electrode post 20. When the bottom end of the electrode post 20 is uneven or tilted, the adaptive part 40 can also adapt to the bottom end of the electrode post 20, filling the uneven area at the bottom end, or forming a sloping plate structure that is thicker on one side and thinner on the other. In this way, the surface of the first pressure plate 50 can be unaffected by the bottom of the electrode post 20, and the first pressure plate 50 can maintain a direction perpendicular to the first direction X during the process of the electrode post 20 transmitting pressure to the battery 90 through the first pressure plate 50.

[0042] In this embodiment, by setting an adaptive unit 40 and a first pressure plate 50, when the bottom of the electrode post 20 is uneven or tilted, the adaptive unit 40 can adjust its thickness along the first direction X based on the pressure of the electrode post 20, so that the surface of the first pressure plate 50 can remain perpendicular to the first direction X. In this way, the first pressure plate 50 is not affected by the direction of force applied by the electrode post 20. The first pressure plate 50 can transmit pressure to the battery 90, so that the powder of the battery 90 is subjected to more uniform force, thereby avoiding damage to the structure, morphology and composition of the battery 90 during the test, resulting in small test error and high test result accuracy.

[0043] The battery 90 in the various embodiments of this application can be a secondary battery or a primary battery; specifically, the battery 90 can be a solid-state battery, such as a solid-state lithium battery, a solid-state sodium battery, or a solid-state magnesium battery, but is not limited thereto. However, for the sake of brevity, the following embodiments will be described using a solid-state lithium battery as an example.

[0044] In this embodiment, the testing device may include two electrode posts 20, which are movably inserted into both ends of the through hole 11; thus, the test cylinder 10 and the two electrode posts 20 together form a test area 12 for accommodating the battery 90. An adaptive part 40 is disposed at the end of either electrode post 20 facing the test area 12.

[0045] One electrode post 20 is movably inserted at the top of the through hole 11, and the other electrode post 20 is movably inserted at the bottom of the through hole 11; the two electrode posts 20 are spaced apart in the through hole 11, and the test tube 10 and the two electrode posts 20 together form a test area 12 for accommodating the battery 90. It is understood that the shape of the through hole 11 should match the two electrode posts 20 to facilitate the insertion of the two electrode posts 20 from both ends of the through hole 11.

[0046] In some possible embodiments, the first pressure plate 50 can be electrically connected to the corresponding electrode post 20 via the adaptive portion 40. Thus, the adaptive portion 40 fills the space between the electrode post 20 and the first pressure plate 50, serving as the electrical connection medium between the first pressure plate 50 and the electrode post 20, achieving coordinated optimization of pressure conduction and current. Furthermore, the testing device does not require a separate electrical connection structure, simplifying the structure and facilitating testing of the battery 90.

[0047] Specifically, with Figure 1 Taking the structure shown as an example, the electrode post 40 located on the lower side is directly electrically connected to the lower end of the battery 90, and the electrode post 40 located on the upper side is electrically connected to the upper end of the battery 90 through the adaptive part 40 and the first pressure plate 50 in sequence. In this way, a current loop can be formed. With the help of an external battery tester, the battery 90 can be charged and discharged. The imaging port of the external CT imager is aligned with the test area, so that CT detection is performed by X-ray, thereby obtaining three-dimensional observation of the electrode material structure and morphology.

[0048] Optionally, the first pressure plate 50 is typically a plate-shaped structure. The first pressure plate 50 is horizontally disposed within the through hole 11. The shape of the plate surface of the first pressure plate 50 can be adapted to the cross-section of the through hole 11, that is, the first pressure plate 50 and the through hole 11 have the same shape and size, or the size of the first pressure plate 50 is slightly smaller than that of the through hole 11. In this way, the first pressure plate 50 will not interfere with the side wall of the test cylinder 10, and the electrode post 20 can transmit pressure to the battery 90 through the first pressure plate 50. On the other hand, it can prevent the positive electrode material and the negative electrode material from leaking out from the gap between the electrode post 20 and the side wall of the through hole 11.

[0049] Optionally, the first pressure plate 50 can be made of copper, stainless steel or aluminum alloy, which has good conductivity and structural strength. The electrode post 20 can transmit pressure to the battery 90 through the first pressure plate 50 and serve as the electrical connection medium between the first pressure plate 50 and the electrode post 20, thereby achieving synergistic optimization of pressure conduction and current.

[0050] Optionally, the electrode post 20 may be made of corrosion-resistant stainless steel or other corrosion-resistant metals, and the embodiments of this application are not limited in this regard.

[0051] In some possible embodiments, see Figure 3 As shown, there are two adaptive parts 40 and two first pressure plates 50. The two adaptive parts 40 are respectively disposed on the ends of the two electrode posts 20 facing the test area 12, and the first pressure plates 50 are covered on the corresponding adaptive parts 40.

[0052] Thus, by setting two adaptive parts 40 and two first pressure plates 50, when the bottom of either of the two electrode posts 20 is uneven or tilted, the thickness of each area of ​​the adaptive part 40 connected to the electrode post 20 along the first direction X can be adaptively adjusted to fill the uneven area at the bottom of the electrode post 20, or to form a sloping plate structure that is thicker on one side and thinner on the other. Furthermore, regardless of which electrode post 20 is tilted or uneven, the two adaptive parts 40 can ensure that the plate surfaces of the two first pressure plates 50 are not affected by the bottom of the electrode post 20. The upper and lower electrode posts 20 are respectively connected to the corresponding first pressure plates 50 through one adaptive part 40, and the two first pressure plates 50 transmit pressure to both ends of the battery 90. The first pressure plates 50 can maintain a direction perpendicular to the first direction X, thereby ensuring that both ends of the battery 90 are subjected to uniform force, thus avoiding damage to the structure, morphology and composition of the battery 90 during the test, resulting in small test errors and high test accuracy.

[0053] In some possible embodiments, see Figure 2 As shown, the testing device also includes a second pressure plate 60, an adaptive part 40 disposed on the end of one of the electrode posts 20 facing the test area 12, a first pressure plate 50 covering the adaptive part 40, and a second pressure plate 60 covering the end of the other electrode post 20 facing the test area 12.

[0054] The second pressure plate 60 can be set at a distance from the first pressure plate 50 above it along the first direction X.

[0055] Specifically, in combination Figure 2 As shown, the second pressure plate 60 can be placed on the end of the lower electrode post 20 facing the test area 12. The electrode post 20 transmits pressure to the lower end of the battery 90 through the second pressure plate 60. By applying force with the entire plate, the powder at the lower end of the battery 90 is subjected to more uniform force. The number of adaptive parts 40 and the first pressure plate 50 can be one. The adaptive part 40 is disposed on the end of the upper electrode post 20 facing the test area 12. When the bottom end of the electrode post 20 is uneven or tilted, the adaptive part 40 can adjust its thickness along the first direction X based on the pressure of the electrode post 20, thereby filling the uneven area at the bottom end of the electrode post 20. This ensures that the surface of the first pressure plate 50 remains perpendicular to the first direction X, ensuring that the upper end of the battery 90 is subjected to uniform force. Ultimately, the first pressure plate 50 and the second pressure plate 60 remain parallel, and the two electrode posts 20 apply pressure to both ends of the battery 90 through the first pressure plate 50 and the second pressure plate 60 respectively, so as to avoid damage to the structure, morphology and composition of the battery 90 during the test, resulting in small test error and high test accuracy.

[0056] Optionally, the structure and material of the second pressure plate 60 can be the same as those of the first pressure plate 50.

[0057] The second pressure plate 60 is typically a plate-shaped structure. The second pressure plate 60 is horizontally disposed within the through hole 11. The shape of the second pressure plate 60 can be adapted to the cross-section of the through hole 11, that is, the second pressure plate 60 and the through hole 11 have the same shape and size, or the size of the second pressure plate 60 is slightly smaller than that of the through hole 11. In this way, the second pressure plate 60 will not interfere with the side wall of the test cylinder 10, and the electrode post 20 can transmit pressure to the battery 90 through the second pressure plate 60. On the other hand, it can prevent the positive electrode material and the negative electrode material from leaking out from the gap between the electrode post 20 and the side wall of the through hole 11.

[0058] The second pressure plate 60 can be made of copper, stainless steel or aluminum alloy, and has good conductivity and structural strength. The electrode post 20 can directly transmit pressure to the battery 90 through the second pressure plate 60 and serve as the electrical connection medium between the second pressure plate 60 and the electrode post 20, thus realizing the synergistic optimization of pressure conduction and current.

[0059] In some possible embodiments, see Figures 1 to 4 As shown, the adaptive unit 40 includes a plurality of metal balls 41, all of which are filled between the electrode post 20 and the first pressure plate 50.

[0060] Multiple metal spheres 41 are filled between the electrode post 20 and the first pressure plate 50 to form a multi-level micro-contact structure.

[0061] On the one hand, when the electrode post 20 is subjected to axial pressure along the first direction X, each metal ball 41 can adjust its own position based on the pressure of the electrode post 20, and thus adjust the thickness of the adaptive part 40 along the first direction X. That is, when the bottom of the electrode post 20 is uneven or tilted, each metal ball 41 will displace and deform based on the morphology of the contact surface with the electrode post 20, thereby dynamically filling the unevenness and gap between the end face of the electrode post 20 and the first pressure plate 50. In this way, the plate surface of the first pressure plate 50 can be unaffected by the bottom of the electrode post 20. During the process of the electrode post 20 transmitting pressure to the battery 90 through the first pressure plate 50, the first pressure plate 50 can maintain a direction perpendicular to the first direction X.

[0062] On the other hand, by filling the space between the end face of the electrode post 20 and the first pressure plate 50 with metal balls 41, the discrete layout of the metal balls 41 disperses the contact stress to multiple micro-contact points, effectively reducing the local current density, avoiding abnormal fluctuations in contact resistance caused by surface oxide layer or contaminants, and ensuring that a continuous low-impedance conductive path is formed between the two, providing a high-precision and highly repeatable electrical contact environment for the testing of the battery 90.

[0063] In some possible embodiments, see Figures 1 to 4As shown, the metal sphere 41 may be made of copper, stainless steel, or aluminum alloy. Copper has high electrical conductivity and good ductility, which can ensure low contact resistance and dynamic deformation capability; stainless steel has the advantages of high structural strength and corrosion resistance, thereby maintaining structural integrity under long-term pressure loading; aluminum alloy can balance lightweight and electrical conductivity, reducing the risk of interface heat accumulation.

[0064] In some possible embodiments, see Figures 1 to 4 As shown, the diameter of the metal sphere 41 is 10µm to 90µm. Specifically, the diameter of the metal sphere 41 can be further selected as 30µm to 70µm. By limiting the diameter of the metal sphere 41, it is ensured that each metal sphere 41 has sufficient space for plastic deformation, and the gaps are better filled through multi-level contact. This ensures that each metal sphere 41 can adjust its position based on the pressure of the electrode post 20, thereby adjusting the thickness of the adaptive part 40 along the first direction X. In addition, it can also avoid stress concentration caused by an excessively large diameter of the metal sphere 41 or interface penetration caused by an excessively small diameter, thus ensuring the uniformity of microcurrent distribution and dynamic pressure buffering effect.

[0065] In some possible embodiments, see Figures 1 to 4 As shown, the adaptive part 40 includes a conductive paste 42 and a plurality of filling balls 43. All the filling balls 43 are filled between the electrode post 20 and the first pressure plate 50. The electrode post 20 and the first pressure plate 50 are electrically connected through the conductive paste 42.

[0066] The conductive paste 42 may include conductive silver paste, which has good conductivity.

[0067] The filling ball 43 can be made of copper, stainless steel, aluminum alloy, rubber, or silicone. Specifically, the rubber can be styrene-butadiene rubber, neoprene rubber, silicone, or polyurethane.

[0068] Multiple filling spheres 43 are filled between the electrode post 20 and the first pressure plate 50, and a multi-level micro-contact structure is formed by conductive paste 42.

[0069] Thus, through the composite structure design of conductive paste 42 and filling spheres 43, a stable three-dimensional conductive network is constructed while achieving dynamic pressure matching between the electrode post and the pressure plate.

[0070] On the one hand, when the electrode post 20 is subjected to axial pressure along the first direction X, the filling balls 43 can be made of elastic material and form a multi-level support skeleton through their discrete distribution. Each filling ball 43 is displaced and deformed based on the morphology of the contact surface with the electrode post 20, thereby dynamically filling the unevenness and gap between the end face of the electrode post 20 and the first pressure plate 50. In this way, the plate surface of the first pressure plate 50 is not affected by the bottom of the electrode post 20. During the process of the electrode post 20 transmitting pressure to the battery 90 through the first pressure plate 50, the first pressure plate 50 can maintain a direction perpendicular to the first direction X, ensuring that the battery 90 is subjected to uniform force.

[0071] On the other hand, through the composite structure design of conductive paste 42 and filling spheres 43, conductive paste 42 penetrates and fills the gaps of filling spheres 43, forming a continuous conductive path between electrode post 20 and first pressure plate 50, optimizing mechanical contact uniformity and current transmission efficiency, and providing a high-precision and highly repeatable electrical contact environment for battery 90 testing.

[0072] In some possible embodiments, see Figures 1 to 4 As shown, the diameter of the filling microspheres 43 is 30µm to 250µm. Specifically, the diameter of the filling microspheres 43 can be further selected as 50µm to 200µm. This allows the filling microspheres 43 to have sufficient space for plastic deformation, enabling better filling of gaps through multi-level contact, ensuring that the conductive paste 42 can fully wet the gaps and form a dense conductive layer. By limiting the diameter of the filling microspheres 43, a stable supporting framework can be formed between them to distribute the pressure of the electrode posts, while avoiding excessively large gaps between the filling microspheres 43 that would lead to uneven current carrying capacity. The filling microspheres 43, in conjunction with the conductive paste 42, achieve elastic adaptation of the micro-contact surface during compression deformation, ensuring uniform micro-current distribution and dynamic pressure buffering effect.

[0073] In some possible embodiments, see Figures 1 to 4 As shown, the adaptive part 40 includes a plurality of elastic balls 44, the outer periphery of which is coated with a conductive layer (not shown), and all the elastic balls 44 fill the space between the electrode post 20 and the first pressure plate 50.

[0074] The elastic ball 44 can be made of rubber or silicone. Specifically, the rubber can be styrene-butadiene rubber, neoprene rubber, silicone, or polyurethane.

[0075] The conductive layer can be one of the following: a conductive carbon layer, a copper plating layer, an aluminum plating layer, or a silver plating layer.

[0076] Multiple elastic spheres 44 are filled between the electrode post 20 and the first pressure plate 50 to form a multi-level micro-contact structure.

[0077] On the one hand, when the electrode post 20 is subjected to axial pressure along the first direction X, each elastic ball 44 can adjust its own position based on the pressure of the electrode post 20, thereby adjusting the thickness of the adaptive part 40 along the first direction X. That is, when the bottom of the electrode post 20 is uneven or tilted, each elastic ball 44 will displace and deform based on the morphology of the contact surface with the electrode post 20, thereby dynamically filling the unevenness and gap between the end face of the electrode post 20 and the first pressure plate 50. In this way, the plate surface of the first pressure plate 50 can be unaffected by the bottom of the electrode post 20. During the process of the electrode post 20 transmitting pressure to the battery 90 through the first pressure plate 50, the first pressure plate 50 can maintain a direction perpendicular to the first direction X, ensuring that the battery 90 is subjected to uniform force.

[0078] On the other hand, the elastic ball 44 fills the gap between the end face of the electrode post 20 and the first pressure plate 50. The conductive layer uniformly coated on the outer periphery of the elastic ball 44 forms densely distributed micro-contact points during compression. The isotropic conductive network ensures low impedance conduction throughout the entire area between the electrode post and the pressure plate, ensuring a continuous low impedance conductive path between them, and providing a high-precision and highly repeatable electrical contact environment for the testing of the battery 90.

[0079] In some possible embodiments, see Figures 1 to 4 As shown, the thickness of the conductive layer is 1µm to 10µm. The diameter of the elastic microsphere 44 is 30µm to 250µm.

[0080] Specifically, the diameter of the elastic microsphere 44 can be further selected to be 50um~200um.

[0081] By limiting the thickness of the conductive layer and the particle size of the elastic microspheres 44, during the process of the electrode post 20 transmitting pressure to the battery 90 through the first pressure plate 50, multiple elastic microspheres 44 are compressed to form densely distributed micro-contact points. While ensuring low interface impedance, the conductive layer of a specific thickness can ensure that the conductive layer does not become brittle.

[0082] By limiting the diameter of the elastic ball 44, it is ensured that each elastic ball 44 has sufficient space for plastic deformation. Through multi-level contact, the gaps are better filled, ensuring that each metal ball 41 can adjust its position based on the pressure of the electrode post 20, thereby adjusting the thickness of the adaptive part 40 along the first direction X. In addition, it can also avoid stress concentration caused by an excessively large diameter of the elastic ball 44 or interface penetration caused by an excessively small diameter, thus ensuring the uniformity of microcurrent distribution and dynamic pressure buffering effect.

[0083] In some possible embodiments, see Figures 1 to 4 As shown, the test cylinder 10 is made of polytetrafluoroethylene polymer material or polyetheretherketone polymer material.

[0084] On the one hand, the test cylinder 10 is made of insulating material to prevent short circuits during the test. On the other hand, the polytetrafluoroethylene polymer material or polyetheretherketone polymer material is a polymer, and the carbon, oxygen and other elements have little impact on CT detection. This can greatly reduce the influence of the material on X-ray absorption during the in-situ test data acquisition process, obtain the test data of the battery in the test area more accurately, and improve the test accuracy.

[0085] In some possible embodiments, the testing apparatus may also include a sealing ring (not shown) that can be fitted onto the electrode post 20 to isolate the testing area 12 from the external environment, thereby improving testing accuracy.

[0086] Optionally, there are two sealing rings 30, which are respectively fitted onto the two electrode posts 20.

[0087] Understandably, to complete the test of battery 90, it is often necessary to prepare a CT imager, a battery tester, and the aforementioned testing equipment. The imaging port of the CT imager is aligned with the test area; the battery tester is electrically connected to the two electrode posts 20 respectively.

[0088] A second aspect of this application provides a method for testing a battery, which uses the aforementioned testing apparatus.

[0089] In the testing device, the testing area 12 can accommodate the battery 90 to be tested, and axial pressure is applied to both ends of the battery 90 through the electrode posts 20.

[0090] Battery 90 typically includes a positive electrode material 92, a solid electrolyte 91, and a negative electrode material 93. The positive electrode material 92 can be one or a combination of lithium cobalt oxide, lithium iron phosphate, lithium manganese iron phosphate, lithium manganese oxide, lithium nickel manganese oxide, ternary materials, iron phosphate salts, and manganese iron phosphate salts. The negative electrode material 93 can be one or a combination of lithium metal sheets, lithium metal alloys, graphite, hard carbon, molybdenum disulfide, lithium titanate, graphene, and silicon-carbon negative electrodes. The solid electrolyte 91 can be an LPSC sulfide solid electrolyte.

[0091] See Figures 1 to 5 As shown, the detection methods include:

[0092] S10. The negative electrode material 93 is placed in the through hole 11 and pressed by two electrode posts 20, the adaptive part 40 and the first pressure plate 50 to form a negative electrode sheet.

[0093] Specifically, the electrode post 20, the adaptive part 40, and the first pressure plate 50 apply a first preset pressure to compress the negative electrode material 93 for a first preset duration; wherein the first preset pressure is 80MPa~400MPa, and the first preset duration is 3min~10min. First, the negative electrode material 93 is placed in the test area 12. Two electrode posts 20 are installed at both ends of the test cylinder 10. The upper electrode post 20 makes slight contact with the negative electrode material 93 through the adaptive part 40 and the first pressure plate 50. A first preset pressure of 80MPa~400MPa is applied through the electrode post 20 and maintained for the first preset duration of 3min~10min to compress the negative electrode material 93 into a thin sheet. Typically, the test cylinder 10 with the electrode post 20 can be placed in a pressure device to obtain sufficient first preset pressure; the pressure device can be a hydraulic press, a cylinder, or other equipment. In some specific settings, the first preset pressure can be set to 100MPa~300MPa and the first preset duration can be set to 5min. This can achieve a better extrusion effect and avoid the negative electrode material 93 from collapsing or having poor molding.

[0094] S20. The solid electrolyte 91 is placed into the through hole 11, and then pressed by the two electrode posts 20, the adaptive part 40, and the first pressure plate 50 to form a composite sheet composed of the negative electrode sheet and the solid electrolyte 91. That is, the negative electrode material 93 and the solid electrolyte 91 constitute a composite sheet.

[0095] Specifically, the electrode post 20, the adaptive part 40, and the first pressure plate 50 apply a second preset pressure to compress the solid electrolyte 91 for a second preset duration; wherein the second preset pressure is 150MPa~400MPa, and the second preset duration is 5min-15min. Remove the upper electrode post 20, along with the adaptive part 40 and the first pressure plate 50 connected to it, from the test cylinder 10. Then, place the solid electrolyte 91 into the test area 12 through the top of the through hole 11. The solid electrolyte 91 should be evenly spread on the upper surface of the negative electrode material 93 sheet. Then, reinsert the upper electrode post 20, the adaptive part 40, and the first pressure plate 50 into the test cylinder 10. The upper electrode post 20 makes slight contact with the solid electrolyte 91 through the adaptive part 40 and the first pressure plate 50. Apply a second preset pressure of 150MPa-400MPa to the negative electrode material 93 and the solid electrolyte 91 through the two electrode posts 40 for a second preset duration of 5min-15min to press the negative electrode material 93 and the solid electrolyte 91 into a composite sheet. Similarly, the test cylinder 10 containing the electrode post 20 can be placed in a pressure device to obtain the above-mentioned second preset pressure. In some specific settings, the second preset pressure can be set to 200MPa-350MPa and the second preset duration can be set to 10min to obtain a better extrusion effect, thereby tightly pressing the negative electrode material 93 and the solid electrolyte 91 together to form a composite sheet.

[0096] S30. The positive electrode material 92 is placed into the through hole 11, and is further pressed by the two electrode posts 20, the adaptive part 40 and the first pressure plate 50. The positive electrode material 92 and the composite sheet are stacked in sequence to form the battery 90. That is to say, the positive electrode material 92, the solid electrolyte 91 and the negative electrode material 93 are stacked in sequence to form the battery 90.

[0097] Specifically, the electrode post 20, the adaptive part 40, and the first pressure plate 50 extrude the positive electrode material 92 under a third preset pressure for a third preset duration; wherein the third preset pressure is 5MPa~250MPa and the third preset duration is 2min-8min. The upper electrode post 20, adaptive part 40, and first pressure plate 50 are removed from the test cylinder 10. Then, the positive electrode material 92 is placed into the test area 12 through the top of the through hole 11. The positive electrode material 92 should be evenly spread on the upper surface of the solid electrolyte 91 sheet. The upper electrode post 20, adaptive part 40, and first pressure plate 50 are then reinstalled into the test cylinder 10. The upper electrode post 20 makes slight contact with the positive electrode material 92 through the adaptive part 40 and the first pressure plate 50. By applying a third preset pressure of 5MPa-250MPa to the electrode post 20 and maintaining it for a third preset time of 2min-8min, the positive electrode material 92, solid electrolyte 91, and negative electrode material 93 are pressed into a battery 90. In this embodiment, the battery 90 is a solid-state battery. Similarly, the test cylinder 10 containing the electrode post 20 can be placed in a pressure device to obtain the aforementioned third preset pressure. In some specific settings, the third preset pressure can be set to 10MPa-200MPa and the third preset duration can be 5min to obtain a better extrusion effect, thereby compressing the positive electrode material 92, the solid electrolyte 91 and the negative electrode material 93 into a battery 90.

[0098] It should be noted that the third preset pressure should generally be less than the second preset pressure to avoid crushing the composite sheet formed by the already pressed positive electrode material 92 and solid electrolyte 91 due to the third preset pressure.

[0099] S50, Perform CT inspection on battery 90 located in test area 12.

[0100] The imaging port of the CT imager is aligned with the test area; thus, CT detection is performed using X-rays to obtain three-dimensional observation of the electrode material structure and morphology; in conjunction with the battery tester and the aforementioned test mold, in-situ test information of battery 90 during the charging and discharging process can be observed.

[0101] During CT scans, a fourth preset pressure can be applied to the battery 90 by the two electrode posts 20. The fourth preset pressure is 0 MPa-100 MPa.

[0102] By setting an adaptive unit 40 and a first pressure plate 50, when the bottom of the electrode post 20 is uneven or tilted, the adaptive unit 40 can adjust its thickness along the first direction X based on the pressure of the electrode post 20, so that the surface of the first pressure plate 50 can remain perpendicular to the first direction X. In this way, the first pressure plate 50 is not affected by the direction of force applied by the electrode post 20. The first pressure plate 50 can transmit pressure to the battery 90, so that the powder of the battery 90 is subjected to more uniform force, thereby avoiding damage to the structure, morphology and composition of the battery 90 during the test, resulting in small test error and high test accuracy.

[0103] In some possible embodiments, see Figures 1 to 5 As shown, step S50 includes the following steps:

[0104] S40. Connect the two electrode posts 20 to the battery tester to charge and discharge the battery 90.

[0105] One electrode of the battery tester is electrically connected to the upper electrode post 20 via a wire, and the other electrode of the battery tester is electrically connected to the lower electrode post 20 via a wire. In this way, the two electrode posts 20 are connected to the positive and negative terminals of the battery 90 respectively to form a current loop, thereby realizing the charging and discharging test of the battery 90.

[0106] Taking solid-state lithium batteries as an example, the charge / discharge rate is 0.1C, and the charge / discharge voltage range is 3.0-4.3V vs. Li+ / Li.

[0107] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A testing apparatus for testing a battery (90), characterized in that, The testing apparatus includes: The test tube (10) has a through hole (11) extending along the first direction (X). The electrode post (20) is movably inserted into the through hole (11), and the test tube (10) and the electrode post (20) together form a test area (12) for accommodating the battery (90). At least one adaptive part (40) and at least one first pressure plate (50), the adaptive part (40) being disposed at the end of the electrode post (20) facing the test area (12), and the first pressure plate (50) covering the side of the corresponding adaptive part (40) facing the test area (12); The adaptive part (40) can adjust its own thickness along the first direction (X) according to the pressure of the electrode post (20) so that the first pressure plate (50) is perpendicular to the first direction (X).

2. The testing apparatus according to claim 1, characterized in that, The first pressure plate (50) can be electrically connected to the corresponding electrode post (20) through the adaptive part (40).

3. The testing apparatus according to claim 1, characterized in that, The number of the adaptive part (40) and the first pressure plate (50) are both two. The plate surfaces of the two first pressure plates (50) are perpendicular to the first direction (X). The adaptive part (40) is respectively disposed on the ends of the two electrode posts (20) facing the test area (12). The first pressure plate (50) covers the corresponding adaptive part (40).

4. The testing apparatus according to claim 1, characterized in that, The testing device further includes a second pressure plate (60), and the adaptive part (40) is disposed on the end of one of the electrode posts (20) facing the test area (12), and the first pressure plate (50) covers the adaptive part (40); The second pressure plate (60) is placed on the end of another electrode post (20) facing the test area (12).

5. The testing apparatus according to any one of claims 1 to 4, characterized in that, The adaptive part (40) includes a plurality of metal balls (41), all of which fill the space between the electrode post (20) and the first pressure plate (50).

6. The testing apparatus according to claim 5, characterized in that, The metal sphere (41) is made of copper, stainless steel, or aluminum alloy; and / or, The diameter of the metal sphere (41) is 10 μm to 90 μm.

7. The testing apparatus according to any one of claims 1 to 4, characterized in that, The adaptive part (40) includes a conductive paste (42) and a plurality of filling balls (43), all of which are filled between the electrode post (20) and the first pressure plate (50). The electrode post (20) and the first pressure plate (50) are electrically connected through the conductive paste (42).

8. The testing apparatus according to claim 7, characterized in that, The conductive paste (42) includes conductive silver paste; and / or, The filling spheres (43) are made of copper, stainless steel, aluminum alloy, rubber, or silicone; and / or, The diameter of the filling microsphere (43) is 30um~250um.

9. The testing apparatus according to any one of claims 1 to 4, characterized in that, The adaptive part (40) includes a plurality of elastic balls (44), the outer periphery of which is coated with a conductive layer, and all of the elastic balls (44) fill the space between the electrode post (20) and the first pressure plate (50).

10. The testing apparatus according to claim 9, characterized in that, The conductive layer is one of a conductive carbon layer, a copper plating layer, an aluminum plating layer, and a silver plating layer; and / or, The thickness of the conductive layer is 1µm to 10µm; and / or, The elastic sphere (44) is made of rubber or silicone; and / or, The diameter of the elastic microsphere (44) is 30um~250um.

Images