Temperature-controllable high-expansion lithium ion battery test fixture

Abstract

The application discloses a controllable temperature high-expansion lithium ion battery test fixture, which comprises two clamping plates for clamping lithium ion batteries, and the clamping plate comprises an inner contact flat plate, high-temperature-resistant foam cotton, a heating layer, a cooling layer and an outer contact flat plate which are sequentially arranged; the heating layer is externally connected with a heating control unit, and the cooling layer is externally connected with a cooling control unit. The heating layer and the cooling layer are arranged between the inner contact flat plate and the outer contact flat plate, the temperature of the inner contact flat plate and the outer contact flat plate is respectively regulated, when the test temperature of the lithium ion battery is greatly different, the relative use of the inner contact flat plate or the outer contact flat plate of the two clamping plates can be conveniently adjusted, meanwhile, the temperature of the inner contact flat plate and the outer contact flat plate can be regulated, the requirement of different test temperatures of the lithium ion battery can be met, the internal temperature of the lithium ion battery can be kept balanced during the test, and the accuracy of the test result is ensured.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery testing technology, and in particular to a temperature-controlled high-expansion lithium-ion battery testing fixture. Background Technology

[0002] Lithium-ion batteries have received widespread attention as an important component of energy storage systems. Currently, the theoretical specific capacity of graphite anode materials used in the market is 372 mAh / g, while the theoretical specific capacity of silicon-carbon composite materials is about 4200 mAh / g, which is more than 10 times higher than that of graphite anodes. The high capacity of silicon-carbon anode materials can fully meet the energy requirements of lithium-ion batteries for pure electric vehicles. Before being put into use, lithium-ion batteries undergo a series of electrical performance and safety performance tests, and can only be put into use after meeting the indicators.

[0003] Meanwhile, the charging and discharging process of silicon-based lithium-ion batteries will produce a huge material volume expansion effect, especially for pouch-type silicon-based lithium-ion batteries. When silicon-based lithium-ion batteries expand during charging and discharging, it will cause deformation of the internal materials of the cell and affect the external module structure. Therefore, silicon-based lithium-ion batteries need to be used under certain constraints.

[0004] Currently, most tests involve temperature variations, ranging from low to high temperatures. To meet the required test temperatures, test cabinets are typically used in conjunction with large temperature chambers. The target lithium-ion battery is constrained by clamps and placed in the temperature environment chamber. The heat dissipation at the ends of the clamps is significantly greater than in other areas, resulting in significant internal temperature differences within the lithium-ion battery. This makes it impossible to guarantee test results at precise temperatures. Furthermore, temperature chambers are space-consuming, expensive, and limited by the available space. Summary of the Invention

[0005] The purpose of this invention is to provide a temperature-controlled, high-expansion lithium-ion battery test fixture, which solves the problems in lithium-ion battery testing where the fixture cannot elastically expand and contract to adapt to the volume expansion of the lithium-ion battery, cannot easily adjust the temperature of the clamping surface when there is a large temperature difference, and cannot adjust the temperature of the clamping surface when the lithium-ion battery test temperature changes, resulting in an unbalanced internal temperature of the lithium-ion battery and inaccurate test results.

[0006] The objective of this invention can be achieved through the following technical solution: a temperature-controlled high-expansion lithium-ion battery test fixture, comprising two clamping plates for clamping the side of a lithium-ion battery, characterized in that: the clamping plates comprise an inner contact plate, a high-temperature resistant foam cotton, a heating layer, a cooling layer and an outer contact plate arranged in sequence.

[0007] As a further solution of the present invention: a heating control unit is externally connected to the heating layer, and a cooling control unit is externally connected to the cooling layer; the heat of the heating layer is transferred to the inner contact flat plate, and the heat of the heating layer is transferred to the outer contact flat plate through the cooling layer.

[0008] As a further solution of the present invention: the inner contact flat plate, the high-temperature resistant foam cotton, the heating layer, the cooling layer and the outer contact flat plate are adhesively combined and formed with each other.

[0009] As a further solution of the present invention: the outer sides of the inner contact flat plate and the outer contact flat plate are smooth and flat, and the materials of the inner contact flat plate and the outer contact flat plate are stainless steel plates or aluminum alloy plates with a thickness of 5 mm - 10 mm.

[0010] As a further solution of the present invention: the high-temperature resistant foam cotton is silicone-type foam cotton, and the density of the high-temperature resistant foam cotton is 250 kg / m3 - 300 kg / m3 and the thickness is 2 mm - 4 mm.

[0011] As a further solution of the present invention: the heating layer is in a zigzag shape, and the heating layer is a magnesium alloy plate or an aluminum alloy plate with a thickness of 0.5 mm - 1.5 mm.

[0012] As a further solution of the present invention: the cooling layer is in a convex shape, and the middle protruding part corresponds to the middle empty area of the zigzag heating layer and there is a heat insulation gap between them.

[0013] As a further solution of the present invention: cooling pipes are arranged inside the cooling layer, the cooling pipes are connected to the cooling control unit, and the cooling control unit controls the circulation of the coolant in the cooling pipes.

[0014] As a further solution of the present invention: a temperature monitor one is installed between the heating layer and the heating control unit, and a temperature monitor two is installed between the cooling layer and the cooling control unit. The temperature monitor one and the temperature monitor two are thermocouples.

[0015] As a further solution of the present invention: the two clamping plates have the same specifications and shapes, and the outer peripheral dimensions of the two clamping plates are larger than the outer peripheral dimensions of the contact surface of the lithium-ion battery to be clamped; the shapes and sizes of the outer peripheries of the inner contact flat plate, the high-temperature resistant foam cotton, the heating layer, the cooling layer and the outer contact flat plate are the same.

[0016] The beneficial effects of the present invention:

[0017] 1. This invention sets up a heating layer and a cooling layer between the inner contact plate and the outer contact plate, and controls the temperature of the inner contact plate and the outer contact plate respectively. When there is a large temperature difference, the relative clamping surfaces of the fixture can be easily adjusted to approach different lithium-ion battery test temperatures. At the same time, the temperature of the inner contact plate and the outer contact plate can be adjusted to meet the requirements of different test temperatures of lithium-ion batteries. This allows the lithium-ion battery to maintain internal temperature balance during testing, ensuring the accuracy of test results.

[0018] 2. The clamp is internally lined with high-temperature resistant foam cotton. The high expansion capacity of the high-temperature resistant foam cotton can adapt to the volume expansion effect when the temperature of the lithium-ion battery changes, making the clamp applicable to a wider range of types and temperatures. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the clamping plate structure of a temperature-controlled high-expansion lithium-ion battery testing fixture according to the present invention.

[0020] Figure 2 This is an exploded structural diagram of the clamping plate of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of a lithium-ion battery cell of the present invention;

[0022] Figure 4 This is a front view of the lithium-ion battery cell of the present invention located in the fixture.

[0023] A. Lithium-ion battery; 10. Clamping plate; 11. Inner contact plate; 12. High-temperature resistant foam cotton; 13. Heating layer; 131. Heating control unit; 132. Temperature monitor one; 14. Cooling layer; 141. Cooling control unit; 142. Temperature monitor two; 15. Outer contact plate. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0025] like Figure 1-4 As shown, the present invention discloses a temperature-controlled high-expansion lithium-ion battery test fixture, including two clamping plates 10 for clamping the side of the lithium-ion battery A. The clamping plates 10 include an inner contact plate 11, a high-temperature resistant foam cotton 12, a heating layer 13, a cooling layer 14 and an outer contact plate 15 arranged in sequence.

[0026] In the design, two clamping plates 10 are respectively clamped on both sides of the lithium-ion battery A. The opposing surfaces of the two clamping plates 10 are both inner contact plates 11 or outer contact plates 15. The inner contact plates 11 or outer contact plates 15 of the two clamping plates 10 are in direct contact with the surface of the lithium-ion battery A.

[0027] The inner contact plate 11 is close to the heating layer 13 and is kept at a high temperature by heat transfer from the heating layer 13. A cooling layer 14 is provided between the outer contact plate 15 and the heating layer 13. The outer contact plate 15 is kept at a low temperature by heat transfer after adjustment by the cooling layer 14. When the temperature difference of the lithium-ion battery A changes greatly, the relative clamping surfaces can be easily adjusted. For example, the inner contact plate 11 can be used as the relative clamping surface at high temperature, and the outer contact plate 15 can be quickly adjusted as the relative clamping surface at low temperature.

[0028] Furthermore, a heating control unit 131 is connected to the heating layer 13, and a cooling control unit 141 is connected to the cooling layer 14; the heat from the heating layer 13 is transferred to the inner contact plate 11, and the heat from the heating layer 13 is transferred to the outer contact plate 15 through the cooling layer 14.

[0029] The heating layer 13 is controlled by the heating control unit 131 to adjust the temperature of the inner contact plate 11, and the cooling layer 14 is controlled by the cooling control unit 141 to regulate the temperature of the outer contact plate 15. This realizes the control of the temperature change of the opposite surfaces of the two clamping plates 10, which can meet the different temperature test requirements of lithium-ion battery A and solve the problem of uneven surface temperature of lithium-ion battery A in the test cabinet, which affects the test results of lithium-ion battery A.

[0030] The clamping plate 10 is equipped with high-temperature resistant foam cotton 12 inside. The high-temperature resistant foam cotton 12 can withstand high temperature and elastic deformation. The high expansion of the high-temperature resistant foam cotton 12 can adapt to the volume expansion of the lithium-ion battery A.

[0031] Furthermore, the inner contact plate 11, high-temperature resistant foam 12, heating layer 13, cooling layer 14, and outer contact plate 15 are bonded together to form a composite structure. This bonding and assembly ensures a tight connection between the components, which is beneficial for heat transfer. The adhesive can be high-temperature resistant silicone, and the bonding method helps to keep the outer surfaces of the inner contact plate 11 and outer contact plate 15 smooth and flat, allowing for closer contact with the lithium-ion battery A.

[0032] Furthermore, the inner contact plate 11 and the outer contact plate 15 are made of stainless steel or aluminum alloy plates with a thickness of 5mm-10mm. The inner contact plate 11 and the outer contact plate 15 are made of stainless steel or aluminum alloy plates with good thermal conductivity. The stainless steel or aluminum alloy plates also have high strength so that the clamping plate 10 is not easily deformed.

[0033] Further, the high-temperature resistant foam cotton 12 is silicone-based foam cotton, and the density of the high-temperature resistant foam cotton 12 is 250 kg / m 3 -300 kg / m 3 , and the thickness is 2 mm - 4 mm. The silicone-based foam cotton can withstand high temperatures and has appropriate density and thickness, which can meet the need of the volume expansion and deformation of the lithium-ion battery A.

[0034] Further, the heating layer 13 is in a zigzag shape. The heating layer 13 is a magnesium alloy plate or an aluminum alloy plate, and the thickness is 0.5 mm - 1.5 mm. The cooling layer 14 is in a convex shape, and the middle protruding part corresponds to the middle empty area of the zigzag heating layer 13 and there is a heat insulation gap between them.

[0035] The heating layer 13 is the heat source of the device. The heating of the heating layer 13 can be carried out in various ways. For example: the heating can be carried out by arranging electric heating tubes, electromagnetic aluminum plates or copper magnetic disks inside or on the surface of the magnesium alloy plate or aluminum alloy plate. It has fast heat generation and is easy to control.

[0036] The cooling layer 14 is in a convex shape, and the middle protruding part corresponds to the middle empty area of the zigzag heating layer 13, forming a snap-fit structure. The heating layer 13 and the cooling layer 14 are stable and not easy to be misaligned with each other. The middle protruding part of the cooling layer 14 and the middle empty area of the zigzag heating layer 13 are arranged at intervals, and the space between them is filled with adhesive, which can maintain the uniformity of heat transfer between the heating layer 13 and the cooling layer, and is conducive to the cooling regulation of the transferred temperature by the cooling layer 14.

[0037] Further, the adjustment of the temperature by the cooling layer 14 can be achieved in various ways. Cooling tubes can be evenly arranged inside the cooling layer 14, and part of the heat can be taken away by the coolant circulating inside the cooling tubes. The circulating flow of the coolant can be connected to a liquid chiller, and the speed of the circulating flow of the coolant can be controlled by the liquid chiller, so as to realize the control of the transferred heat by the cooling layer 14.

[0038] Further, a temperature monitor 132 is installed between the heating layer 13 and the heating control unit 131; a temperature monitor 14 is installed between the cooling layer 14 and the cooling control unit 141. The temperature monitors 132 and 142 use thermocouples. The thermocouples can convert temperature into electrical signals, and connecting the electrical signals to the control circuit can realize the automatic control of the heating control unit 131 and the cooling control unit 141. The control circuit can be a PLC controller or a single-chip microcomputer, which has many applications in reality.

[0039] Furthermore, the two clamping plates 10 are identical in specifications and shape, and their outer circumference is larger than that of the contact surface of the lithium-ion battery A. The clamping plates 10, being larger than the contact surface of the lithium-ion battery A and fully conforming to it, can maintain a uniform temperature on the contact surface of the lithium-ion battery A, ensuring internal temperature balance and guaranteeing the rigor and precision of the test results. The inner contact plate 11 has the same shape and size as the high-temperature resistant foam 12, heating layer 13, cooling layer 14, and outer contact plate 15. This creates a tight, solid clamping structure, resulting in more even and controllable heat transfer between components.

[0040] Working principle of the invention: By setting a heating layer 13 and a cooling layer 14 inside the clamping plate 10, the temperature of the two sides of the same clamping plate 10 is different and controllable. When the two clamping plates 10 are used in a group with their opposite faces, the large temperature difference of the surface can be conveniently used for different lithium-ion batteries A to meet the requirements of large temperature difference. Adjusting the surface temperature of the clamping plate 10 can meet the different temperature testing requirements of lithium-ion batteries A. When lithium-ion batteries A are tested in the test cabinet, the surface temperature is kept uniform, the test of lithium-ion batteries A is more accurate, and the rigor and precision of the test results are ensured.

[0041] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. The present invention is not limited to the above embodiments; the embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

[0042] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0043] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention 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 present invention.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "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, an electrical connection, or a connection that allows communication between them; 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, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0046] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of 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. "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.

Claims

1. A temperature-controlled high-expansion lithium-ion battery test fixture, comprising two clamping plates (10) for clamping the side of a lithium-ion battery (A), characterized in that: The clamping plate (10) includes an inner contact flat plate (11), a high-temperature resistant foam cotton (12), a heating layer (13), a cooling layer (14) and an outer contact flat plate (15) which are arranged in layers in sequence; The heating layer (13) is externally connected with a heating control unit (131), and the cooling layer (14) is externally connected with a cooling control unit (141); the heat of the heating layer (13) is transferred to the inner contact flat plate (11), and the heat of the heating layer (13) is transferred to the outer contact flat plate (15) through the cooling layer (14); The heating layer (13) is in a zigzag shape, and the heating layer (13) is a magnesium alloy plate or an aluminum alloy plate with a thickness of 0.5 mm - 1.5 mm; The cooling layer (14) is in a convex shape, and the middle protruding part corresponds to the middle empty area of the zigzag heating layer (13) and there is a heat insulation gap between them; Cooling pipes are arranged inside the cooling layer (14), the cooling pipes are connected to the cooling control unit (141), and the cooling control unit (141) controls the circulating flow of the coolant in the cooling pipes; A first temperature monitor (132) is installed between the heating layer (13) and the heating control unit (131), and a second temperature monitor (142) is installed between the cooling layer (14) and the cooling control unit (141), and the first temperature monitor (132) and the second temperature monitor (142) are thermocouples; The inner contact flat plate (11), the high-temperature resistant foam cotton (12), the heating layer (13), the cooling layer (14) and the outer contact flat plate (15) are bonded and combined to form a shape; Among them, when high temperature is required, the inner contact flat plate (11) is used as the relative clamping surface, and when low temperature is required, the outer contact flat plate (15) is quickly adjusted as the relative clamping surface.

2. The temperature-controlled high-expansion lithium-ion battery test fixture according to claim 1, characterized in that, The outer sides of the inner contact flat plate (11) and the outer contact flat plate (15) are smooth and flat, and the materials of the inner contact flat plate (11) and the outer contact flat plate (15) are stainless steel plates or aluminum alloy plates with a thickness of 5 mm - 10 mm.

3. The temperature-controlled high-expansion lithium-ion battery test fixture according to claim 1, characterized in that, The high-temperature resistant foam (12) is an organosilicon-type foam, and the density of the high-temperature resistant foam (12) is 250 kg / m³. 3 -300kg / m 3 Thickness is 2mm-4mm.

4. The temperature-controlled high-expansion lithium-ion battery test fixture according to claim 1, characterized in that: The specifications and shapes of the two clamping plates (10) are the same, and the outer peripheral dimensions of the two clamping plates (10) are larger than the outer peripheral dimensions of the contact surface of the clamped lithium-ion battery (A); the shapes and sizes of the outer peripheries of the inner contact flat plate (11), the high-temperature resistant foam cotton (12), the heating layer (13), the cooling layer (14) and the outer contact flat plate (15) are the same.

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