Battery in-situ testing device suitable for wide temperature range

Abstract

The invention relates to the field of batteries, and discloses a battery in-situ testing device suitable for a wide temperature range, the battery in-situ testing device comprises a first shell and a second shell, the first shell is internally provided with a first accommodating cavity with one closed end, the first accommodating cavity is used for accommodating a to-be-tested sample, the second shell covers the first shell so that the other end of the first accommodating cavity is closed, and the first accommodating cavity is used for accommodating the to-be-tested sample. The top of the second shell is provided with an observation window, the observation window can observe a to-be-tested sample in the first accommodating cavity through the observation channel, an annular second accommodating cavity is arranged outside the first accommodating cavity, a temperature control part is arranged in the second accommodating cavity, and the temperature control part controls the test temperature of the first accommodating cavity based on the Peltier effect. The sample cell provided by the invention is suitable for wide temperature range conditions, can be combined with synchrotron radiation analysis and gas product detection, has a lateral visual observation function, is reasonable in overall structural design and high in compatibility, can stably operate in a temperature range of-20 DEG C to 70 DEG C, and is adaptive to various in-situ characterization platforms.

Description

Technical Field

[0001] The present invention relates to the field of batteries, and in particular to a battery in-situ testing device suitable for a wide temperature range. Background Art

[0002] With the rapid development of technologies such as new energy vehicles, aerospace, and grid energy storage, lithium-ion batteries are facing higher requirements for energy density, safety, and environmental adaptability. High-energy-density batteries, represented by lithium metal anodes, high-nickel ternary materials, and lithium-rich layered cathode materials, are widely considered to be important candidates for the next generation of energy storage systems. However, in practical applications, especially under wide temperature ranges (e.g., -20°C to 70°C), these batteries still face serious problems such as reduced safety and shortened cycle life, which restricts their promotion and application in complex climates and extreme working conditions.

[0003] The specific failure process usually involves the combined effects of multiple factors such as changes in the positive electrode crystal structure, lattice oxygen release, electrolyte decomposition, lithium dendrite growth, and migration and deposition of transition metal ions. It is highly dynamic, localized, and multi-scale coupled. Therefore, an in-situ testing device that can adapt to extreme environmental changes and has multimodal functions is needed to deeply analyze the evolution of these materials and the performance degradation mechanism. However, existing in-situ testing devices usually lack integrated temperature control components and cannot accurately adjust and stably maintain the battery operating environment over a wide temperature range. Summary of the Invention

[0004] The purpose of the present invention is to overcome the problem that the existing technology cannot regulate the battery operating temperature in a wide temperature range, and to provide a battery in-situ testing device suitable for a wide temperature range. The sample cell can regulate the temperature of the battery operating environment in a wide temperature range.

[0005] In order to achieve the above-mentioned objectives, the present invention provides a battery in-situ testing device suitable for a wide temperature range, comprising a first shell and a second shell, wherein the first shell has a first accommodating chamber with one end closed, and the first accommodating chamber is used to accommodate a sample to be tested. The second shell is buckled onto the first shell so that the other end of the first accommodating chamber is closed. An observation window is provided on the top of the second shell, and the observation window can observe the sample to be tested in the first accommodating chamber through an observation channel. An annular second accommodating chamber is provided outside the first accommodating chamber, and a temperature control unit is installed in the second accommodating chamber, which controls the test temperature of the first accommodating chamber based on the Peltier effect.

[0006] Using this technical solution, the temperature control unit uses the Peltier effect to control the test temperature of the first chamber. More specifically, by adjusting the direction and magnitude of the input current, it can achieve active heating or cooling of the test sample environment. Compared with traditional temperature control methods using heating plates or liquid circulation systems, semiconductor temperature control chips have significant advantages such as small size, high integration, fast response speed, and high temperature control accuracy. They can complete the heating or cooling process of the sample chamber in a short time, support stable operation in a wide temperature range of -20°C to 70°C, and do not require large external auxiliary equipment, greatly improving the compactness of the overall structure and space utilization efficiency.

[0007] Preferably, a first gas channel and a second gas channel are provided in the second shell, wherein the outer ends of the first gas channel and the second gas channel are both connected to the outside world, and the inner ends of the first gas channel and the second gas channel are both connected to the first accommodating chamber. The outside world refers to the external environment. With the above structure, gas can be blown into the first channel, so that the gas generated during battery operation can flow out of the second channel together with the blown-in gas, facilitating collection and analysis, thereby meeting the detection requirements of DEMS (in situ differential electrochemical mass spectrometry).

[0008] Preferably, a light-transmitting window and a light signal collecting window are provided on the first shell, and the axes of the two coincide with each other. External light can pass through the light-transmitting window into the first accommodating cavity, and light in the first accommodating cavity can pass through the light signal collecting window back to the outside world. When this structure is used for X-ray or other optical analysis, the corresponding light can be injected through the light-transmitting window, and this injected light passes through the sample to be tested and then passes through the light signal collecting window, thereby facilitating the analysis. If necessary, two groups of light-transmitting windows and light signal collecting windows can be set, one of which can be used to inject the corresponding analysis light, and when the light intensity is insufficient, the other group can be used to increase the supplementary light intensity. Unlike the traditional device with only an observation window on the top, the sample cell provided in the present application is specially provided with a light-transmitting window and a light signal collecting window on the first shell. This window is very necessary for observing the formation of lithium dendrites in the battery (the traditional top window cannot be used to observe the situation where lithium dendrites are formed).

[0009] Preferably, a limit sleeve is disposed within the first accommodating cavity. The limit sleeve is made of a transparent material, and its inner cavity forms the first accommodating cavity. With this structure, the sample to be tested is placed within the limit sleeve, which acts as a circumferential limiter. Furthermore, the limit sleeve is made of a transparent material that allows light to pass through, ensuring smooth passage of the optical observation light path.

[0010] Preferably, a preload mechanism is provided between the second housing and the test sample to apply a preset axial preload force to the test sample. This mechanism allows the preload mechanism to preload the desired pressure, providing axial positional constraints for the test sample and allowing the preload pressure to be set within a desired range for pressure analysis.

[0011] Preferably, a first gasket is provided at the bottom of the first accommodating cavity, the limiting sleeve is provided on the first gasket, the first gasket is made of metal, one of the positive electrode or the negative electrode of the sample to be tested contacts the first gasket, and the first gasket is connected to the corresponding electrode of the power supply;

[0012] A second gasket is provided on the surface of the sample to be tested close to the pre-tightening structure. The second gasket is made of metal. The pre-tightening structure and the second shell are both made of metal. One end of the pre-tightening structure presses the second gasket against the other pole of the sample to be tested, and the other end of the pre-tightening structure presses against the second shell. The second shell is connected to the corresponding pole of the power supply.

[0013] With the above structure, the sample to be tested can be conveniently connected to the positive and negative electrodes of the power supply through the first gasket and the second gasket, thereby completing the test by powering on.

[0014] Preferably, the preload structure includes at least one preload spring, with the uppermost preload spring pressing against the second housing, and the lowermost preload spring pressing against the second gasket. This structure is simple, and a certain number of springs can be selected according to the required preload pressure.

[0015] Preferably, the preload spring is a butterfly spring, all of the butterfly springs are stacked together along the axial direction of the first accommodating cavity, a first hole is formed in all of the butterfly springs, a hollow limiting column is installed on the surface of the second housing close to the butterfly springs, the limiting column extends into the hole of the uppermost butterfly spring, and the uppermost butterfly spring is pressed against the second housing, and the lowermost butterfly spring is pressed against the second gasket, and the second gasket is provided with a second hole;

[0016] The cavity in the limiting column, the first hole, and the second hole are connected to form the observation channel.

[0017] Using this technical solution, the butterfly springs themselves are approximately butterfly-shaped, with one end larger than the other. By stacking them, the butterfly springs can be positioned and limited. The top butterfly spring is limited by the limiting post, while the bottom butterfly spring is limited by the sample to be tested. The axes of the holes through the butterfly springs, the inner cavity of the limiting post, and the second hole in the first gasket overlap to form a through channel, which constitutes the observation channel, facilitating observation of the sample through the observation window.

[0018] Preferably, the observation window is covered with optical glass; the temperature control unit is a semiconductor temperature control piece. By installing optical glass on the observation window, the entire structure is sealed, meeting some test requirements that require sealed operation.

[0019] Preferably, a third hole is formed on the first housing corresponding to the second accommodating cavity, and the power line of the semiconductor temperature control piece passes through the third hole to connect to the semiconductor temperature control piece. With this structure, the third hole facilitates the connection between the semiconductor temperature control piece and the power supply.

[0020] Through the above technical solution, the sample cell provided in this application is suitable for wide temperature conditions, can be combined with synchrotron radiation analysis and gas product detection, and has lateral visualization observation function. The entire structure is reasonably designed and highly compatible. It can operate stably in the temperature range of -20°C to 70°C, and is compatible with a variety of in-situ characterization platforms. It is suitable for the study of the structure, interface and reaction process mechanism of high-energy-density lithium battery materials in complex environments, and provides a solution for the analysis of battery failure mechanisms under extreme conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the three-dimensional structure of a battery in-situ testing device suitable for a wide temperature range;

[0022] Figure 2 This is an exploded view of a battery in-situ testing device suitable for a wide temperature range;

[0023] Figure 3 is a schematic diagram of the three-dimensional structure of the second shell;

[0024] Figure 4 is a schematic diagram of the planar structure of the second shell;

[0025] Figure 5 yes Figure 4 AA cross-sectional view;

[0026] Figure 6 It is a schematic diagram of the three-dimensional structure of the first shell.

[0027] Description of Reference Numerals

[0028] 1-first shell; 1a-shell base; 1b-bottom plate; 2-second shell; 3-first accommodating chamber; 4-observation window; 5-optical glass; 6-sealing ring; 7-first gas channel; 8-limiting column; 9-butterfly spring; 10-first hole; 11-second gasket; 12-second hole; 13-limiting sleeve; 14-first gasket; 15-semiconductor temperature control plate; 16-light-transmitting window; 17-optical signal collection window; 18-second gas channel; 19-sealing groove; 20-third hole; 21-second accommodating chamber. DETAILED DESCRIPTION

[0029] In the description of this application, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application 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 therefore should not be understood as a limitation on this application.

[0030] The terms "first", "second", etc. are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein. The objects distinguished by "first", "second", etc. are generally of the same type and do not limit the number of objects. For example, the first object can be one or more.

[0031] In addition, the term "and / or" in the specification and claims is used to describe an association relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0032] In the description of the present application, unless otherwise specified, “plurality” means two or more.

[0033] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0034] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0035] In one embodiment, a battery in-situ testing device suitable for a wide temperature range is disclosed, such as Figure 1-6 As shown, it includes a first shell 1 and a second shell 2. The first shell 1 has a first accommodating chamber 3 with one end closed, and the first accommodating chamber 3 is used to accommodate the sample to be tested. The second shell 2 is buckled on the first shell 1 so that the other end of the first accommodating chamber 3 is closed. An observation window 4 is provided on the top of the second shell 2, and the observation window 4 can observe the sample to be tested in the first accommodating chamber 3 through an observation channel. An annular second accommodating chamber 21 is provided outside the first accommodating chamber 3, and a temperature control unit is installed in the second accommodating chamber 21. The temperature control unit controls the test temperature of the first accommodating chamber based on the Peltier effect.

[0036] Generally speaking, bolt holes can be opened on the first housing 1 , and the second housing 2 can be tightened on the first housing 1 by bolts.

[0037] In one embodiment, the temperature control component is a semiconductor temperature control piece 15 , and a third hole 20 is opened on the first shell corresponding to the second accommodating cavity 21 , and the power line of the semiconductor temperature control piece 15 passes through the third hole 20 and is connected to the semiconductor temperature control piece 15 .

[0038] In one embodiment, a first gas channel 7 and a second gas channel 18 are defined within the second housing 2. The outer ends of the first gas channel 7 and the second gas channel 18 are both connected to the outside world, while the inner ends of the first gas channel 7 and the second gas channel 18 are both connected to the first accommodating chamber 3. Thus, the gas generated by the sample during testing can be delivered to the first accommodating chamber 3 through the first gas channel 7. The delivered gas, carrying the gas generated by the sample, flows out through the second gas channel 18, and the outflowing gas is collected for further component analysis.

[0039] like Figure 6As shown, in one embodiment, a light-transmitting window 16 and an optical signal collecting window 17 are provided on the first shell, and the axes of the two coincide with each other. External light can pass through the light-transmitting window 16 into the first accommodating cavity 3, and light in the first accommodating cavity 3 can pass through the optical signal collecting window 17 back to the outside world. Generally speaking, the light-transmitting window 16 is larger than the optical signal collecting window 17. In order to improve the sealing performance of the entire structure, optical glass is installed in both the light-transmitting window 16 and the optical signal collecting window 17, and the optical glass is sealed on all sides by sealant. Of course, in order to facilitate different detections, such as X-ray detection, fluorescence detection and other different needs, two groups of light-transmitting windows 16 and optical signal collecting windows 17 can be opened.

[0040] like Figure 2 As shown, in one embodiment, a limiting sleeve 13 is provided in the first accommodating chamber 3 . The limiting sleeve 13 is made of a transparent material, and the inner cavity of the limiting sleeve 13 forms the first accommodating chamber 3 .

[0041] In one embodiment, a pre-tightening structure is provided between the second housing 2 and the sample to be tested, and the pre-tightening structure is used to apply a preset axial pre-tightening force to the sample to be tested. In this application, the axial direction coincides with the axial direction of the first accommodating cavity.

[0042] In one embodiment, a first gasket 14 is provided at the bottom of the first accommodating cavity 3, and the limiting sleeve 13 is installed on the first gasket 14. The first gasket 14 is made of metal. One of the positive or negative poles of the sample to be tested contacts the first gasket 14, and the first gasket 14 is connected to the corresponding pole of the power supply. A second gasket 11 is provided on the surface of the sample to be tested close to the pre-tightening structure. The second gasket 11 is made of metal. The pre-tightening structure and the second shell 2 are both made of metal. One end of the pre-tightening structure presses the second gasket 11 against the other pole of the sample to be tested, and the other end of the pre-tightening structure presses against the second shell 2, and the second shell 2 is connected to the corresponding pole of the power supply.

[0043] Generally speaking, the negative electrode of the sample to be tested can be brought into contact with the first gasket 14, the first gasket 14 is connected to the negative electrode of the power supply, and the second gasket 11 is pressed against the positive electrode of the sample to be tested by the pre-tightening structure, and then the second shell 2 is connected to the positive electrode of the power supply. Since the second gasket 11, the pre-tightening structure and the second shell 2 are all made of metal, the connection between the positive electrode of the sample to be tested and the positive electrode of the power supply is achieved.

[0044] In one embodiment, the pre-tightening structure includes at least one pre-tightening spring, the uppermost pre-tightening spring is closely connected to the second housing 2 , and the lowermost pre-tightening spring is pressed against the second gasket 11 .

[0045] In one embodiment, the preload spring is a butterfly spring 9, and all the butterfly springs 9 are stacked together along the axial direction of the first accommodating chamber 3. A first hole 10 is opened through all the butterfly springs 9, and an internal hollow limit column 8 is installed on the surface of the second shell 2 close to the butterfly spring 9. The limit column 8 extends into the hole of the topmost butterfly spring 9, and the topmost butterfly spring 9 is pressed against the second shell 2, and the bottommost butterfly spring 9 is pressed against the second gasket 11. A second hole 12 is opened on the second gasket 11, and the axis of the cavity in the limit column 8, the axis of the first hole 10, and the axis of the second hole 12 coincide with the axis of the first accommodating chamber 3. The cavity in the limit column 8, the first hole 10 and the second hole 12 are connected to form the observation channel, and the observation window 4 is opposite to the observation channel and is connected with it.

[0046] In one embodiment, the observation window 4 is covered with an optical glass 5, and the observation window 4 is sealed by the optical glass 5, so that the interior of the sample pool remains sealed. In order to further improve the sealing performance, a sealing ring 6 can be provided between the optical glass 5 and the observation window 4. Furthermore, the sealing ring 6 is divided into two, one large and one small. Two sealing grooves 19 can be provided at the bottom of the observation window 4. The two sealing grooves 19 are provided from the inside to the outside around the cavity end of the limiting column 8. The small sealing ring 6 is installed in the sealing groove 19 near the cavity end of the limiting column 8, and the large sealing ring 6 is installed in the sealing groove 19 on the outside.

[0047] In one embodiment, Figure 5 As shown, in order to increase the ventilation volume, two first gas channels 7 can be opened, and the two first gas channels 7 and one second gas channel 18 are arranged in a "Y" shape, and their inner ends are connected to the cavity in the limiting column 8, and the cavity in the limiting column 8 is connected to the first accommodating chamber 3 through the first hole 10 and the second hole 12, so that the inner ends of the first gas channel 7 and one second gas channel 18 are connected to the first accommodating chamber 3, and their outer ends are connected to the outside world.

[0048] In one embodiment, Figure 2 As shown, the first shell 1 includes a shell base 1a, which has an internal cavity with open ends. The surface of the shell base 1a facing away from the second shell 2 is installed with a bottom plate 1b, and the two are connected by bolts. The bottom plate 1b closes one end of the internal cavity with open ends to form the first accommodating cavity 3. The second accommodating cavity 21 is provided on the surface of the shell base 1a for covering the second shell 2, and the light-transmitting window 16 and the optical signal collecting window 17 are provided on the side wall of the shell base 1a.

[0049] Furthermore, in one embodiment, in order to facilitate the observation of the other end of the sample to be tested, another observation window can be opened on the bottom plate 1b, and the observation window is opposite to the cavity inside the shell base 1a. The observation window on the bottom plate 1b is also installed with optical glass like the observation window on the second shell 2. A fourth hole is opened on the first gasket 14, and the other end of the sample to be tested can be observed through the fourth hole from the observation window on the bottom plate 1b.

[0050] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A battery in-situ testing device suitable for a wide temperature range, comprising a first housing and a second housing, characterized in that: The first shell has a first accommodating chamber with one end closed, which is used to accommodate the sample to be tested. The second shell is buckled onto the first shell so that the other end of the first accommodating chamber is closed. An observation window is provided on the top of the second shell, and the observation window can observe the sample to be tested in the first accommodating chamber through an observation channel. An annular second accommodating chamber is provided outside the first accommodating chamber, and a temperature control unit is installed in the second accommodating chamber. The temperature control unit controls the test temperature of the first accommodating chamber based on the Peltier effect.

2. The testing device according to claim 1, wherein: A first gas channel and a second gas channel are defined in the second shell. The outer ends of the first gas channel and the second gas channel are both communicated with the outside, and the inner ends of the first gas channel and the second gas channel are both communicated with the first accommodating cavity.

3. The testing device according to claim 1 or 2, wherein: The first shell is provided with a light-transmitting window and an optical signal collecting window, and the axes of the two coincide. External light can pass through the light-transmitting window into the first accommodating cavity, and light in the first accommodating cavity can pass through the optical signal collecting window back to the outside world.

4. The testing device according to claim 3, wherein: A limiting sleeve is provided in the first accommodating cavity. The limiting sleeve is made of a transparent material, and the inner cavity of the limiting sleeve forms the first accommodating cavity.

5. The testing device according to claim 4, wherein: A pre-tightening structure is provided between the second housing and the sample to be tested, and the pre-tightening structure is used to apply a preset axial pre-tightening force to the sample to be tested. The testing device according to claim 5 , wherein: A first gasket is provided at the bottom of the first accommodating cavity, and the limiting sleeve is provided on the first gasket. The first gasket is made of metal. One of the positive electrode or the negative electrode of the sample to be tested contacts the first gasket, and the first gasket is connected to the corresponding electrode of the power supply. A second gasket is provided on the surface of the sample to be tested close to the pre-tightening structure. The second gasket is made of metal. The pre-tightening structure and the second shell are both made of metal. One end of the pre-tightening structure presses the second gasket against the other pole of the sample to be tested, and the other end of the pre-tightening structure presses against the second shell. The second shell is connected to the corresponding pole of the power supply.

7. The testing device according to claim 6, wherein: The pre-tightening structure includes at least one pre-tightening spring, the uppermost pre-tightening spring is pressed against the second housing, and the lowermost pre-tightening spring is pressed against the second gasket.

8. The testing device according to claim 7, wherein: The preload spring is a butterfly spring, all of which are stacked together along the axial direction of the first accommodating cavity, and a first hole is formed in all of the butterfly springs. A hollow limiting column is installed on the surface of the second housing close to the butterfly springs, and the limiting column extends into the hole of the uppermost butterfly spring. The uppermost butterfly spring is pressed against the second housing, and the lowermost butterfly spring is pressed against the second gasket, which is provided with a second hole. The cavity in the limiting column, the first hole, and the second hole are connected to form the observation channel.

9. The testing device according to any one of claims 4 to 8, wherein: The observation window is covered with optical glass; The temperature control unit is a semiconductor temperature control piece.

10. The testing device according to claim 9, wherein: A third hole is formed on the first shell corresponding to the second accommodating cavity, and a power line of the semiconductor temperature control piece passes through the third hole and is connected to the semiconductor temperature control piece.

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