Solid-state battery performance test method and system

Abstract

The invention provides a solid-state battery performance testing method and system, and relates to the technical field of battery performance testing. According to the method, pressure is applied to the solid-state battery, the pressure value is gradually changed, in-situ CT imaging detection and electrochemical performance detection are carried out on the solid-state battery in the pressure change process, and coupling analysis is carried out on the pressure value, CT image information and electrochemical parameters; the mutual relation and evolution rule among the pressure value, the CT image information and the electrochemical parameters are summarized, so that the comprehensive performance characterization of the battery under different pressure conditions is realized, and more comprehensive and accurate data support is provided for deeply understanding the performance evolution of the battery in the actual use process; the internal relation between the internal structure change of the battery and the electrochemical performance can be disclosed, and an important theoretical basis and a guidance direction are provided for the optimization design of a battery material and the improvement of the battery performance.

Description

Technical Field

[0001] The present invention relates to the technical field of battery performance testing, and in particular to a method and system for testing the performance of a solid-state battery. Background Art

[0002] As an emerging energy storage technology, solid-state batteries show great application potential in electric vehicles, portable electronic devices, and large-scale energy storage systems. With the increasing demand for batteries with higher energy density and better safety, the research and development of solid-state batteries have received extensive attention.

[0003] In terms of the performance evaluation of solid-state batteries, the existing technologies usually adopt two main methods: CT (Computed Tomography) imaging technology and pressure analysis technology. CT imaging technology can achieve non-destructive three-dimensional reconstruction of the internal structure of the battery, providing high-resolution internal topography information, which is suitable for studying the microscopic changes of battery materials under different charge and discharge states; the pressure analysis technology is to test the electrochemical performance of the battery under static pressure conditions, and simulate some actual working conditions by applying a certain pressure to evaluate the influence of external mechanical stress on the battery performance.

[0004] However, in actual application scenarios, the working environment of solid-state batteries is much more complex than laboratory conditions. The battery not only has to withstand various mechanical stresses from the outside, but also has to cope with the volume expansion and contraction changes caused by charge and discharge cycles inside. Simply relying on the above two methods to separately analyze the pressure-bearing performance of the battery or observe its internal topography characteristics is difficult to comprehensively and accurately evaluate the true performance of the solid-state battery. Especially during the dynamic charge and discharge process, the physical and chemical reactions occurring inside the battery are more complex, and the existing detection means cannot effectively capture these instantaneous changes and their influence on the overall performance of the battery. This not only limits the understanding of the internal mechanism of solid-state batteries by researchers, but also is insufficient to support work such as the optimization design of battery materials, the accurate evaluation of battery performance, and the efficient development of battery systems. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for testing the performance of a solid-state battery to alleviate the technical problem of relatively one-sided performance testing of solid-state batteries in the prior art.

[0006] In a first aspect, the method for testing the performance of a solid-state battery provided by the present invention includes the following steps:

[0007] Apply pressure to the solid-state battery and gradually change the pressure value;

[0008] During the pressure change process, perform in-situ CT imaging detection and electrochemical performance detection on the solid-state battery;

[0009] Perform a coupled analysis of the pressure value, CT image information, and electrochemical parameters, and summarize the mutual relationships and evolution laws among the pressure value, CT image information, and electrochemical parameters.

[0010] Combined with the first aspect, the present invention provides a first possible implementation manner of the first aspect, wherein the step of applying pressure to the solid-state battery and gradually changing the pressure value includes:

[0011] Set an initial pressure value and a pressure limit value, use a preset pressure difference value as the change gradient, gradually change the pressure value, and maintain a preset duration under each level of pressure condition.

[0012] Combined with the first aspect, the present invention provides a second possible implementation manner of the first aspect, wherein the step of performing a coupled analysis of the pressure value, CT image information, and electrochemical parameters, and summarizing the mutual relationships and evolution laws among the pressure value, CT image information, and electrochemical parameters includes:

[0013] Select a time period during which the pressure value increases or decreases, and compare and analyze the change trend of the CT image gray-scale signal;

[0014] Identify the location where the CT image gray-scale signal is higher than the preset gray-scale maximum value or lower than the preset gray-scale minimum value;

[0015] In the case where the CT image gray-scale signal is higher than the preset gray-scale maximum value or lower than the preset gray-scale minimum value, judge the evolution trend of the electrochemical parameters during the corresponding time period.

[0016] Combined with the first aspect, the present invention provides a third possible implementation manner of the first aspect, wherein the step of performing a coupled analysis of the pressure value, CT image information, and electrochemical parameters, and summarizing the mutual relationships and evolution laws among the pressure value, CT image information, and electrochemical parameters includes:

[0017] Select a time period during which the pressure value increases or decreases, and compare and analyze the voltage change trend of the solid-state battery;

[0018] Under the condition that the pressure value and the voltage value increase or decrease continuously, judge whether there is a region where the CT image gray-scale signal is higher than the preset gray-scale maximum value or lower than the preset gray-scale minimum value.

[0019] Combined with the first aspect, the present invention provides a fourth possible implementation manner of the first aspect, wherein the solid-state battery performance testing method further includes:

[0020] During the charging or discharging process of the solid-state battery, detect the voltage of the solid-state battery, and analyze the mutual relationships and evolution laws among the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information.

[0021] Combined with the fourth possible implementation manner of the first aspect, the present invention provides a fifth possible implementation manner of the first aspect, wherein the steps of analyzing the mutual relationship and evolution law of the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information include:

[0022] During the charging or discharging process of the solid-state battery, comparatively analyze the change trend of the internal pressure of the solid-state battery;

[0023] Under the condition that the pressure value continuously increases or decreases, determine whether there is a region where the CT image gray signal is higher than the preset gray maximum value or lower than the preset gray minimum value.

[0024] Combined with the fourth possible implementation manner of the first aspect, the present invention provides a sixth possible implementation manner of the first aspect, wherein the steps of analyzing the mutual relationship and evolution law of the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information include:

[0025] Change the charging or discharging rate of the solid-state battery until the internal pressure of the solid-state battery reaches the pressure limit value, or there is a region where the CT image gray signal is higher than the preset gray maximum value or lower than the preset gray minimum value.

[0026] In a second aspect, the solid-state battery performance testing system provided by the present invention includes: a pressure testing tooling, a CT detector, a charge and discharge device, a controller, and a memory;

[0027] The pressure testing tooling, the CT detector, and the charge and discharge device are respectively connected to the controller;

[0028] The controller is communicatively connected to the memory, and when the controller executes the computer program stored in the memory, the solid-state battery performance testing method described in the first aspect is implemented.

[0029] Combined with the second aspect, the present invention provides a first possible implementation manner of the second aspect, wherein the pressure testing tooling includes: a mounting seat, a support member, a pressurizing member, a pressure sensor, and a pressing seat;

[0030] The support member and the pressurizing member are respectively connected to the mounting seat;

[0031] The pressing seat is slidably engaged with the support member, and the pressure sensor is installed between the pressurizing member and the pressing seat.

[0032] Combined with the first possible implementation manner of the second aspect, wherein the pressurizing member includes: a die core, a die head, and a gland;

[0033] The mold core is connected to the mounting base, the mold head is slidably fitted to the mold core, and the gland is mounted on the end of the mold head close to the pressure sensor.

[0034] The embodiments of the present invention bring the following beneficial effects: By applying pressure to the solid-state battery and gradually changing the pressure value, during the pressure change process, in-situ CT imaging detection and electrochemical performance detection are carried out on the solid-state battery, and the pressure value, CT image information, and electrochemical parameters are coupled and analyzed to summarize the mutual relationship and evolution law between the pressure value, CT image information, and electrochemical parameters, realizing the comprehensive performance characterization of the battery under different pressure conditions, providing more comprehensive and accurate data support for deeply understanding the performance evolution of the battery during actual use, being conducive to revealing the internal connection between the internal structure change and electrochemical performance of the battery, and providing an important theoretical basis and guiding direction for the optimized design of battery materials and the improvement of battery performance.

[0035] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in related technologies, the following will briefly introduce the drawings required for use in the description of the specific embodiments or related technologies. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 It is a schematic flowchart of the method for testing the performance of the solid-state battery provided by the embodiment of the present invention;

[0038] Figure 2 It is a schematic diagram of the solid-state battery performance test system provided by the embodiment of the present invention;

[0039] Figure 3 It is a schematic diagram of the pressure test tooling of the solid-state battery performance test system provided by the embodiment of the present invention;

[0040] Figure 4 It is a cross-sectional view of the pressure test tooling of the solid-state battery performance test system provided by the embodiment of the present invention.

[0041] Reference numerals: 100 - pressure test tooling; 110 - mounting base; 120 - support member; 130 - pressure applying member; 131 - mold core; 132 - mold head; 133 - gland; 140 - pressure sensor; 150 - clamping seat; 200 - CT detector; 300 - charge and discharge device; 400 - controller; 500 - memory. Detailed implementation manners

[0042] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0043] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. For the physical quantities in the formula, if not otherwise specified, they should be understood as the basic quantities of the basic units in the International System of Units, or the derived quantities derived from the basic quantities through mathematical operations such as multiplication, division, differentiation or integration.

[0044] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0045] As Figure 1 shown, the solid-state battery performance testing method provided by the embodiment of the present invention includes the following steps: applying pressure to the solid-state battery and gradually changing the pressure value; during the pressure change process, performing in-situ CT imaging detection and electrochemical performance detection on the solid-state battery; performing coupled analysis on the pressure value, CT image information, and electrochemical parameters to summarize the mutual relationship and evolution law between the pressure value, CT image information, and electrochemical parameters.

[0046] In the solid-state battery performance testing method described in this embodiment, through the coupled analysis of pressure values, CT image information, and electrochemical parameters, it helps to identify the key factors for battery performance degradation, providing an important theoretical basis and guiding direction for the optimized design of battery materials and the improvement of battery performance. During the pressure change process, in-situ CT imaging detection and electrochemical performance detection of the solid-state battery can be taken into account, which can reveal the internal connection between the internal structure change and electrochemical performance of the battery, achieving a comprehensive performance characterization of the battery under different pressure conditions. It can not only observe the change of the internal structure of the battery but also monitor the electrochemical performance of the battery in real time, providing more comprehensive and accurate data support for deeply understanding the performance evolution of the battery during actual use.

[0047] In the embodiment of the present invention, the steps of applying pressure to the solid-state battery and gradually changing the pressure value include: setting an initial pressure value and a pressure limit value, taking a preset pressure difference value as the change gradient, gradually changing the pressure value, and maintaining a preset duration under each pressure condition.

[0048] Among them, the initial pressure value can be set to zero, or the initial pressure value can be preset as a pressure value sufficient to squeeze the battery to make its deformation amount reach a preset deformation amplitude. The pressure limit value should be increased as much as possible under the condition of ensuring safety, so as to realize the performance test of the battery under the extreme pressure condition. The preset pressure difference value can be increased or decreased according to the pressure-bearing performance of the battery material to be measured. By reducing the preset pressure difference value, a relatively smooth pressure curve can be obtained, and thus the test data is more delicate.

[0049] In an alternative embodiment, the steps of performing a coupled analysis of the pressure value, CT image information, and electrochemical parameters, and summarizing the mutual relationship and evolution law among the pressure value, CT image information, and electrochemical parameters include: selecting a time period when the pressure value increases or decreases, and comparing and analyzing the change trend of the CT image gray-scale signal; identifying the location where the CT image gray-scale signal is higher than a preset gray-scale maximum value or lower than a preset gray-scale minimum value; in the case where the CT image gray-scale signal is higher than the preset gray-scale maximum value or lower than the preset gray-scale minimum value, judging the evolution trend of the electrochemical parameters during the corresponding time period.

[0050] Among them, the CT image gray-scale signal being higher than the preset gray-scale maximum value represents that the image is brighter and the material density is higher; the CT image gray-scale signal being lower than the preset gray-scale minimum value represents that the image is darker and the material density decreases, which may be caused by pores, cracks, or low-density deposits. In the case where the CT image gray-scale signal is too large or too small, further analyzing the evolution trend of the electrochemical parameters is conducive to confirming the reason for the abnormal change of the CT image gray-scale signal.

[0051] When the material density in a solid-state battery is high, the possible reasons include: lithium metal deposition, accumulation of side reaction products, and local pressure increase. Lithium metal deposition: With an increase in local lithium deposition and a high lithium density, uneven deposition may occur, leading to an increase in local current density, inducing dendrite growth, and interface densification. When side reaction products accumulate, interface reactions result in the formation of deposits, increasing the interface impedance and causing battery performance degradation; when the local pressure increases, due to the massive accumulation of lithium in certain areas, local material densification occurs, which may be related to uneven lithium deposition or mechanical stress; in the case of interface densification, the electrolyte or SEI (Solid Electrolyte Interface) layer thickens, which may affect lithium-ion migration and further increase the interface impedance.

[0052] When the material density in a solid-state battery is low, the possible reasons include: pores, disappearance of lithium metal, dendrite growth, and interface debonding. In the case of pore formation, electrolyte decomposition, mechanical damage, and poor interface contact may affect ion migration; when lithium metal disappears, it means that lithium is consumed or migrates to other areas, which may lead to local lithium depletion and increased polarization; during dendrite growth, local areas may become sparse, which may lead to a short-circuit risk; in the state of interface debonding, interface contact is lost, the interface impedance increases, and the cycle stability decreases.

[0053] Furthermore, the steps for coupling and analyzing the pressure value, CT image information, and electrochemical parameters to summarize the mutual relationship and evolution law among the pressure value, CT image information, and electrochemical parameters include: selecting a time period during which the pressure value increases or decreases, and comparing and analyzing the voltage change trend of the solid-state battery; under the conditions that the pressure value and the voltage value increase and decrease continuously respectively, determining whether there are regions in the CT image gray-scale signal that are higher than the preset maximum gray-scale value or lower than the preset minimum gray-scale value.

[0054] When performing battery performance analysis, not only can the influence of pressure on the voltage change trend be obtained, and the response degree of the voltage change trend to pressure be known, but it can also be experimentally determined whether there are abnormalities in the CT image gray-scale signal under charge and discharge conditions, as well as when the external pressure suddenly increases or decreases, so as to evaluate the stability of the battery material under extreme working conditions.

[0055] In this embodiment, the solid-state battery performance test method further includes: during the charging or discharging process of the solid-state battery, detecting the voltage of the solid-state battery, and analyzing the mutual relationship and evolution law among the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information.

[0056] Further, the steps for analyzing the mutual relationship and evolution law of the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information include: during the charging or discharging process of the solid-state battery, comparatively analyzing the change trend of the internal pressure of the solid-state battery; under the condition that the pressure value continuously increases or decreases, judging whether there is a region where the CT image gray signal is higher than the preset gray maximum value or lower than the preset gray minimum value.

[0057] The steps for analyzing the mutual relationship and evolution law of the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information include: changing the charging or discharging rate of the solid-state battery until the internal pressure of the solid-state battery reaches the pressure limit value, or there is a region where the CT image gray signal is higher than the preset gray maximum value or lower than the preset gray minimum value.

[0058] Adopting the above implementation method to realize the performance test of the solid-state battery is applicable to various types of solid-state batteries, such as solid-state lithium batteries, solid sodium batteries, etc., and has wide applicability and popularization value, and can provide strong technical support for battery material research, battery performance evaluation, and the development of battery systems.

[0059] In the case of high gray scale, increasing voltage, and increasing pressure, the side reactions are enhanced, and the side reaction products are deposited, resulting in an increase in the density of the electrode / electrolyte interface. At the same time, the side reactions consume active lithium, intensifying the battery polarization (increasing voltage) and hindering ion transport.

[0060] In the case of high gray scale, increasing voltage, and decreasing pressure, the solid electrolyte is infiltrated and the structure is relaxed, and lithium gradually penetrates into the solid electrolyte, reducing the local pressure. However, the side reactions still cause the voltage to increase, and the high gray scale region may originate from the by-products.

[0061] In the case of high gray scale, decreasing voltage, and increasing pressure, local lithium deposition and dendrite germination occur, and lithium is locally enriched, resulting in an increase in local pressure, but at the same time reducing the local impedance.

[0062] In the case of high gray scale, decreasing voltage, and decreasing pressure, lithium dendrites grow and the electrolyte is damaged. A large number of lithium dendrites grow, reducing the local contact pressure. At the same time, due to the growth of lithium at the interface, it may cause a short circuit or reduce polarization (voltage drop).

[0063] In the case of low gray scale, increasing voltage, and increasing pressure, the electrolyte degrades and the structure densifies. The reasons that can be analyzed include: local side reactions cause damage to the solid electrolyte, but the density increases, reducing the CT gray scale value, and the increase in battery side reactions leads to intensified polarization (increasing voltage).

[0064] In the case of low gray scale, increasing voltage, and decreasing pressure, the electrolyte is damaged and its structure becomes loose. The electrolyte decomposes to form pores, which in turn causes the CT gray scale value to decrease. The decreasing pressure indicates a weakened structural support ability, and at the same time, the side reactions of the battery increase (voltage increases).

[0065] In the case of low gray scale, decreasing voltage, and increasing pressure, local lithium deposition occurs along with electrolyte damage. The deposited lithium may be relatively dispersed and does not form a dense structure (gray scale decreases), but due to local excessive deposition, the pressure still increases. At the same time, the change in the battery reaction impedance causes the voltage to drop.

[0066] In the case of low gray scale, decreasing voltage, and decreasing pressure, severe dendrite growth occurs, the electrolyte is damaged over a large area, and the lithium dendrites expand, making the electrolyte structure loose (gray scale decreases). The reasons for the decreasing pressure include an uneven interface or weakened mechanical support. Moreover, the short circuit of lithium dendrites or the damage of SEI reduces the voltage.

[0067] As Figure 2 and Figure 3 shown, the solid-state battery performance testing system provided by the embodiments of the present invention includes: a pressure testing tooling 100, a CT detector 200, a charge and discharge device 300, a controller 400, and a memory 500; the pressure testing tooling 100, the CT detector 200, and the charge and discharge device 300 are respectively connected to the controller 400; the controller 400 is communicatively connected to the memory 500, and the controller 400 executes the computer program stored in the memory 500 and implements the solid-state battery performance testing method described in the above embodiments.

[0068] Specifically, the pressure testing tooling 100 can pressurize the battery under test and can detect the pressure it applies and the reaction force of the battery. The CT detector 200 uses in-situ CT imaging technology to perform real-time and non-destructive imaging characterization of the internal structure of the battery, obtaining the internal morphological changes of the battery under different pressure conditions, such as three-dimensional structure information of key regions such as the electrode interface and electrolyte distribution. The charge and discharge device 300 can charge or discharge the battery under test and can add test functions to detect parameters such as the voltage, capacity, and impedance of the battery.

[0069] As Figure 3 and Figure 4As shown, in the embodiment of the present invention, the pressure test tooling 100 includes: a mounting base 110, a support member 120, a pressurizing member 130, a pressure sensor 140, and a pressing seat 150; the support member 120 and the pressurizing member 130 are respectively connected to the mounting base 110; the pressing seat 150 is slidably engaged with the support member 120, and the pressure sensor 140 is installed between the pressurizing member 130 and the pressing seat 150. Among them, the pressurizing member 130 can generate pressure through the telescopic action of an electric telescopic device, or apply pressure to the pressure sensor 140 through a hydraulic telescopic device, and then push and press the pressing seat 150 to act on the battery under test.

[0070] In this embodiment, the pressurizing member 130 includes: a die core 131, a die head 132, and a gland 133; the die core 131 is connected to the mounting base 110, the die head 132 is slidably engaged with the die core 131, and the gland 133 is installed at the end of the die head 132 close to the pressure sensor 140. Among them, a sealing ring is installed between the die core 131 and the die head 132, and the die head 132 can be driven to expand and contract relative to the die core 131 by introducing high-pressure liquid into the die core 131. In addition, a notch groove can be provided on the gland 133, and a terminal for connecting the battery electrode can be detachably installed in the notch groove. After loading the battery, the terminal and the electrode are connected through a lead, which is convenient for installation and avoids hindering the imaging scan of the battery.

[0071] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing the performance of a solid-state battery, characterized in that, Including the following steps: Applying pressure to the solid-state battery and gradually changing the pressure value; During the pressure change process, performing in-situ CT imaging detection and electrochemical performance detection on the solid-state battery; Performing coupled analysis on the pressure value, CT image information, and electrochemical parameters, and summarizing the mutual relationship and evolution law among the pressure value, CT image information, and electrochemical parameters.

2. The performance testing method of the solid-state battery according to claim 1, wherein The step of applying pressure to the solid-state battery and gradually changing the pressure value includes: Setting an initial pressure value and a pressure limit value, using a preset pressure difference as the change gradient, gradually changing the pressure value, and maintaining a preset duration under each pressure condition.

3. The method for testing the performance of a solid-state battery according to claim 1, wherein The step of performing coupled analysis on the pressure value, CT image information, and electrochemical parameters, and summarizing the mutual relationship and evolution law among the pressure value, CT image information, and electrochemical parameters includes: Selecting a time period when the pressure value increases or decreases, and comparatively analyzing the change trend of the CT image gray-scale signal; Identifying the location where the CT image gray-scale signal is higher than a preset gray-scale maximum value or lower than a preset gray-scale minimum value; When the CT image gray-scale signal is higher than the preset gray-scale maximum value or lower than the preset gray-scale minimum value, judging the evolution trend of the electrochemical parameters during the corresponding time period.

4. The method for testing the performance of a solid-state battery according to claim 1, characterized in that, The step of performing coupled analysis on the pressure value, CT image information, and electrochemical parameters, and summarizing the mutual relationship and evolution law among the pressure value, CT image information, and electrochemical parameters includes: Selecting a time period when the pressure value increases or decreases, and comparatively analyzing the voltage change trend of the solid-state battery; Under the condition that the pressure value and the voltage value increase or decrease continuously respectively, judging whether there is an area where the CT image gray-scale signal is higher than a preset gray-scale maximum value or lower than a preset gray-scale minimum value.

5. The method for testing the performance of a solid-state battery according to any one of claims 1 to 3, characterized in that It also includes: During the charging or discharging process of the solid-state battery, detecting the voltage of the solid-state battery, and analyzing the mutual relationship and evolution law among the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information.

6. The method for testing the performance of a solid-state battery according to claim 5, wherein The step of analyzing the mutual relationship and evolution law among the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information includes: During the charging or discharging process of the solid-state battery, comparatively analyzing the change trend of the internal pressure of the solid-state battery; Under the condition that the pressure value increases or decreases continuously, judging whether there is an area where the CT image gray-scale signal is higher than a preset gray-scale maximum value or lower than a preset gray-scale minimum value.

7. The method for testing the performance of a solid-state battery according to claim 5, characterized in that, The step of analyzing the mutual relationship and evolution law among the voltage of the solid-state battery, the internal pressure of the solid-state battery, and the CT image information includes: Changing the charging or discharging rate of the solid-state battery until the internal pressure of the solid-state battery reaches the pressure limit value, or there is an area where the CT image gray-scale signal is higher than a preset gray-scale maximum value or lower than a preset gray-scale minimum value.

8. A solid-state battery performance testing system, characterized in that, Including: A pressure test tooling (100), a CT detector (200), a charge and discharge device (300), a controller (400), and a memory (500); The pressure test tooling (100), the CT detector (200), and the charge and discharge device (300) are respectively connected to the controller (400); The controller (400) is communicatively connected to the memory (500), and the controller (400) executes the computer program stored in the memory (500) to implement the solid-state battery performance testing method according to any one of claims 1-7.

9. The solid-state battery performance testing system according to claim 8, wherein, The pressure test tooling (100) includes: a mounting base (110), a support member (120), a pressurizing member (130), a pressure sensor (140), and a pressing seat (150); The support member (120) and the pressurizing member (130) are respectively connected to the mounting base (110); The pressing seat (150) is slidably fitted to the support member (120), and the pressure sensor (140) is installed between the pressurizing member (130) and the pressing seat (150).

10. The solid-state battery performance testing system according to claim 9, wherein The pressurizing member (130) includes: a die core (131), a die head (132), and a gland (133); The die core (131) is connected to the mounting base (110), the die head (132) is slidably fitted to the die core (131), and the gland (133) is installed at the end of the die head (132) close to the pressure sensor (140).

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