Battery cell pressurizing structure

Abstract

The utility model discloses a battery cell pressurizing structure which comprises a charging and discharging cabinet and a pressure-bearing sealing box, the charging and discharging cabinet is connected with a charging and discharging interface wire, the charging and discharging interface wire is connected into the pressure-bearing sealing box, a battery cell placing plate is arranged in the pressure-bearing sealing box, and the battery cell placing plate is connected with the charging and discharging interface wire. And the air pressure pressurizing device is connected with the pressure-bearing sealing box. The utility model aims to solve the technical problems in the prior art, and provides a battery cell pressurizing structure, which adopts air pressure to replace physical contact type pre-tightening of a hard clamp, ensures uniform stress at each part, and does not cause unbalanced stress and influence the performance and the service life due to unbalanced expansion at the later period of the life cycle of a battery cell.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium battery detection, in particular to a battery core pressurizing structure. Background Art

[0002] Lithium-ion batteries have a series of advantages such as high energy density, good safety, high energy efficiency, low self-discharge rate, and good cycle stability. Therefore, they are widely used in production and life. Because lithium-ion batteries produce gas under working conditions such as high temperature, high voltage or long-term low power storage, the contact of the electrode pieces becomes loose. Therefore, during the application process, a pre-tightening force is generally applied to the battery cell to ensure stable interface contact during the cycle and cycle performance. Therefore, during the test process, it is necessary to simulate the actual working conditions and pressurize the battery cell products for cycling. At present, pre-tightening is mainly applied by clamping with a hard clamp. However, due to the slight difference in thickness between the head and tail of the battery cell, the pre-tightening of the entire body is unbalanced during the pressurization process using this method, resulting in an unbalanced stress effect on the battery cell, which causes the battery cell performance to degrade or even fail.

[0003] Therefore, it is of great significance to develop a simple and convenient pressurization method that can balance the preload when applied to battery cells. Utility Model Content

[0004] 1. Technical problems to be solved by the utility model

[0005] The purpose of the utility model is to solve the technical problems existing in the prior art and to provide a battery cell pressurization structure, which replaces the physical contact pre-tightening of a hard clamp with air pressure to ensure uniform force everywhere and avoid unbalanced force caused by unbalanced expansion in the later stage of the battery cell's life cycle, thereby affecting performance and life.

[0006] 2. Technical solution

[0007] In order to solve the above problems, the technical solution provided by the present invention is as follows:

[0008] A battery cell pressurizing structure includes a charging and discharging cabinet and a pressure-bearing sealed box. The charging and discharging cabinet is connected to a charging and discharging interface wire, and the charging and discharging interface wire is connected to the pressure-bearing sealed box. The pressure-bearing sealed box is provided with a battery cell storage plate, and also includes an air pressure pressurizing device connected to the pressure-bearing sealed box.

[0009] Optionally, the battery cell storage plate is provided with multiple layers spaced apart in the upper and lower parts in the pressure-bearing sealed box.

[0010] Optionally, the battery cell storage plate is a porous plate.

[0011] Optionally, a battery clip is provided on the battery storage plate, and the battery clip is connected to the charge and discharge interface wire.

[0012] Optionally, the air pressure pressurizing device includes an air storage tank connected to the pressure-bearing sealed box, and a pressure valve is connected between the air storage tank and the pressure-bearing sealed box.

[0013] Optionally, the air pressure pressurizing device further includes a pressure gauge connected to the pressure-bearing sealing box.

[0014] Optionally, the pressure valve includes a coarse-adjustment pressure valve and a fine-adjustment pressure valve.

[0015] Optionally, the pressure-bearing sealed box includes a pressure-bearing sealed box main box body and a pressure-bearing sealed box sealing door, and a hollow door sealing strip is provided between the pressure-bearing sealed box main box body and the pressure-bearing sealed box sealing door.

[0016] Optionally, a module cable connection sealing plate that cooperates with the charging and discharging interface wires is provided on the main box body of the pressure-bearing sealed box.

[0017] 3. Beneficial effects

[0018] Compared with the prior art, the technical solution provided by this utility model has the following beneficial effects:

[0019] This cell pressurization structure replaces the physical contact pre-tightening of rigid fixtures with air pressure, ensuring uniform force distribution throughout the cell. This prevents uneven force distribution caused by unbalanced expansion later in the cell's lifecycle, which could impact performance and lifespan. Furthermore, this cell pressurization structure is not restricted by packaging method and can be used with square cells, such as those with soft packs and aluminum cases, as well as cylindrical cells. Its force limitation is solely related to the maximum load capacity of the cell structure in different directions. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a battery core pressurization structure proposed in an embodiment of the present utility model;

[0021] Figure 2 This is a cross-sectional schematic diagram of a pressure-bearing sealing box in a battery core pressurization structure proposed in an embodiment of the present utility model;

[0022] 1. Charging and discharging cabinet; 2. Pressure-bearing sealed box; 21. Pressure-bearing sealed box main body; 22. Pressure-bearing sealed box sealing door; 23. Hollow door sealing strip; 24. Module cable connection sealing plate; 3. Charging and discharging interface wires; 4. Battery cell clamp; 5. Gas storage tank; 6. Pressure gauge; 7. Coarse-adjustment pressure valve; 8. Fine-adjustment pressure valve; 9. Battery cell storage plate. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0024] It should be noted that when an element is referred to as being "fixed on", "set on", "fixed on" or "installed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a central element at the same time. Furthermore, when an element is considered to be "fixedly connected" to another element, the two may be fixed in a detachable manner or in a non-detachable manner, such as socketing, snap-fitting, integrally molded fixing, welding, etc., which can be achieved in the prior art and will not be described in detail here. When an element is perpendicular or approximately perpendicular to another element, it means that the ideal state of the two is vertical, but due to the influence of manufacturing and assembly, there may be a certain vertical error. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of this invention are intended solely for the purpose of describing specific embodiments and are not intended to limit this invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] The “first” and “second” involved in the present invention do not represent specific quantities and orders, but are only used to distinguish names.

[0027] Combined with attachment Figure 1 and 2 A battery cell pressurizing structure of this embodiment includes a charging and discharging cabinet 1 and a pressure-bearing sealed box 2. The charging and discharging cabinet 1 is connected to a charging and discharging interface wire 3. The charging and discharging interface wire 3 is connected to the pressure-bearing sealed box 2 as a power and electrical signal transmission device. The charging and discharging interface wire 3 is sealedly connected to the pressure-bearing sealed box 2. A battery cell storage plate 9 is provided in the pressure-bearing sealed box 2 to meet the placement needs of the battery cells. It also includes an air pressure pressurizing device connected to the pressure-bearing sealed box 2.

[0028] This cell pressurization structure replaces the physical contact pre-tightening of rigid fixtures with air pressure, ensuring uniform force distribution throughout the cell. This prevents uneven force distribution caused by unbalanced expansion later in the cell's lifecycle, which could impact performance and lifespan. Furthermore, this cell pressurization structure is not restricted by packaging method and can be used with square cells, such as those with soft packs and aluminum cases, as well as cylindrical cells. Its force limitation is solely related to the maximum load capacity of the cell structure in different directions.

[0029] As a preferred solution of the present invention, the battery cell storage plate 9 is arranged with multiple layers in the upper and lower parts of the pressure-bearing sealed box 2. The battery cell storage plate 9 is a porous plate, which separates the upper and lower layers of the battery cell storage plate 9 in the pressure-bearing sealed cabinet to meet the placement needs of multiple battery cells.

[0030] As a preferred solution of the present invention, a battery cell clip 4 is provided on the battery cell storage plate 9, and the battery cell clip 4 is connected to the charge and discharge interface wire 3. The battery cell clip 4 serves as a clamp for connecting the positive and negative pole ears of the battery cell to meet the electrical connection between the battery cell and the charge and discharge cabinet, and the connection operation is more convenient.

[0031] As a preferred embodiment of the present invention, the air pressure boosting device includes an air storage tank 5 connected to the pressure-bearing sealed box 2, and a pressure valve is connected between the air storage tank 5 and the pressure-bearing sealed box 2. The pressure valve is arranged on the connecting pipeline between the air storage tank 5 and the pressure-bearing sealed box 2. The pressure valve is a valve that roughly adjusts the pressure of the pipeline medium by changing the cross-sectional area between the valve core and the valve seat. In this embodiment, the pressure valve includes a coarse-adjustment pressure valve 7 and a fine-adjustment pressure valve 8. The method for adjusting the internal pressure of the pressure-bearing sealed box is to connect a high-pressure air source, adjust the coarse-adjustment pressure valve 7 so that the internal pressure of the pressure-bearing sealed box reaches a certain high pressure, and adjust the fine-adjustment pressure valve 8 so that the air pressure in the pressure-bearing sealed box 2 reaches the required value; when the air pressure in the pressure-bearing sealed box 2 is less than the set value, air intake begins, and when the air pressure is greater than the set value, the effect of stabilizing the air pressure in the pressure-bearing sealed box is achieved.

[0032] As a preferred solution of the present invention, the high-pressure gas source is an inert gas, such as Ar or N2, which helps to enhance the safety attributes during the test process.

[0033] As a preferred solution of the present invention, in order to display the pressure inside the pressure-bearing sealed box 2 in real time, the air pressure pressurizing device further includes a pressure gauge 6 connected to the pressure-bearing sealed box 2, and the pressure gauge 6 is preferably a digital pressure gauge.

[0034] As a preferred solution of the present invention, the pressure-bearing sealed box 2 includes a pressure-bearing sealed box main box body 21 and a pressure-bearing sealed box sealing door 22. The pressure-bearing sealed box main box body 21 and the pressure-bearing sealed box sealing door 22 are tightly connected by a door buckle. A hollow door sealing strip 23 is provided between the pressure-bearing sealed box main box body 21 and the pressure-bearing sealed box sealing door 22, which is mainly used to ensure a sealed environment and achieve a certain sealing level under the vertical pressure provided by the cabinet door lock.

[0035] As a preferred solution of the present invention, a module cable connection sealing plate 24 that cooperates with the charging and discharging interface wire 3 is provided on the main box body 21 of the pressure-bearing sealed cabinet. The module cable connection sealing plate 24 serves as a device to ensure the sealing of the cabinet when entering the pressure-bearing sealed cabinet. The module cable connection sealing plate 24 is provided with a through hole that allows the charging and discharging interface wire 3 to pass through, and the charging and discharging interface wire 3 and the module cable connection sealing plate 24 are sealed by silicone sealant.

[0036] The battery cell pressurization structure includes the following steps: S1, obtaining the air pressure value inside the battery cell packaging shell; S2, placing the battery cell in a pressure-bearing sealed box 2, which can withstand at least two atmospheres of pressure for a long time without structural damage to meet the battery cell pressurization requirements and meet the sealing requirements of no pressure leakage under long-term positive pressure conditions; S3, connecting the battery cell to the charge and discharge interface wire 3, and sealing the electrical connection point between the charge and discharge interface wire 3 and the battery cell. The charge and discharge interface wire 3 is led out from the external charge and discharge cabinet 1, and the access point of the charge and discharge interface wire 3 and the pressure-bearing sealed box 2 is sealed with silicone. The sealing is performed, and each sealing box is connected to at least 4 charging and discharging channels (channels that cooperate with the charging and discharging interface wires 3) to ensure the use needs of multiple samples; S4, connect the high-pressure gas source, and adjust the internal pressure of the pressure sealing box 2 to the same as the air pressure inside the battery cell packaging shell; S5, continue to increase the internal pressure of the pressure sealing box 2 until the pre-tightening pressure required by the battery cell is reached. For square battery cells, before the pressure on the side or top reaches the maximum pressure limited by the structure of the battery cell at that part, the pressurization can be continuously carried out to reach the pre-tightening pressure required for the large surface. At this time, the force condition of the large surface of the battery cell in the sealing box is F=P*S large surface.

[0037] The above is a schematic description of the present invention and its embodiments, which is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by this and, without departing from the inventive purpose of the present invention, designs a structure and embodiment similar to the technical solution without inventiveness, they shall fall within the scope of protection of the present invention.

Claims

1. A battery cell pressurization structure, characterized in that: It includes a charging and discharging cabinet and a pressure-bearing sealed box. The charging and discharging cabinet is connected to a charging and discharging interface wire, and the charging and discharging interface wire is connected to the pressure-bearing sealed box. The pressure-bearing sealed box is provided with a battery storage plate and also includes an air pressure pressurizing device connected to the pressure-bearing sealed box.

2. The battery core pressurizing structure according to claim 1, characterized in that: The battery cell storage plate is provided with multiple layers in the pressure-bearing sealed box at intervals up and down.

3. The battery core pressurizing structure according to claim 1, characterized in that: The battery cell storage plate is a porous plate.

4. The battery core pressurizing structure according to claim 1, characterized in that: The battery storage plate is provided with a battery clip, and the battery clip is connected to the charge and discharge interface wire.

5. A battery core pressurizing structure according to any one of claims 1 to 4, characterized in that: The air pressure pressurizing device includes an air storage tank connected to the pressure-bearing sealed box, and a pressure valve is connected between the air storage tank and the pressure-bearing sealed box.

6. The battery core pressurizing structure according to claim 5, characterized in that: The air pressure pressurizing device also includes a pressure gauge connected to the pressure-bearing sealing box.

7. The battery core pressurizing structure according to claim 5, characterized in that: The pressure valve includes a coarse adjustment pressure valve and a fine adjustment pressure valve.

8. A battery core pressurizing structure according to any one of claims 1 to 4, characterized in that: The pressure-bearing sealed box comprises a pressure-bearing sealed box main box body and a pressure-bearing sealed box sealing door. A hollow door sealing strip is provided between the pressure-bearing sealed box main box body and the pressure-bearing sealed box sealing door.

9. The battery core pressurizing structure according to claim 8, characterized in that: The main box body of the pressure-bearing sealed box is provided with a module cable connection sealing plate that cooperates with the charging and discharging interface wires.

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