Pole column type battery cell and battery pack

Abstract

The utility model discloses a kind of pole column type electric core and battery, pole column type electric core includes shell, cover plate, electric core winding body and electrolyte, electric core winding body and electrolyte are set in shell, positive pole and negative pole are set on cover plate, positive pole and negative pole are insulatedly connected with cover plate, the positive pole of electric core winding body is connected with positive pole, the negative pole of electric core winding body is connected with negative pole, by setting electric core winding body around flow guide groove, flow guide groove is set as the cylindrical cavity structure of two ends opening, significantly increase the heat exchange area of electric core and outside, so that heat can be more quickly conducted from electric core interior to outside, to effectively reduce the temperature when electric core works, reduce heat accumulation.

Description

Technical Field

[0001] This utility model relates to the technical field of post-type battery cells, and in particular to a post-type battery cell with better heat distribution. Background Technology

[0002] Terminal-type battery cells have been widely used in power battery systems and electrochemical energy storage devices due to their superior performance, such as high energy density, long cycle life, and low self-discharge rate. However, during operation, the cells continuously generate heat. If heat dissipation is not timely, heat accumulation can easily occur, causing the cell temperature to rise rapidly and even inducing thermal runaway. Simultaneously, battery packs composed of numerous individual cells often suffer from uneven temperature distribution during operation. This not only accelerates the degradation of battery performance but also significantly increases the safety risks of system operation. Therefore, efficient and reasonable thermal management of battery packs is a crucial step in ensuring their safe and reliable operation.

[0003] To improve the heat dissipation performance of battery packs, cooling channel designs that allow for full contact with the cell casing and effective heat exchange are commonly employed. Flat cooling pipes or heat pipes have become the mainstream choice, as this structure increases the contact area with the cell, thereby improving heat exchange efficiency. However, due to limitations in the geometry and thermal conductivity of terminal block cells, their heat conduction capacity per unit area remains relatively limited. This hinders the improvement of the overall heat dissipation efficiency of the battery pack and results in significant uneven temperature distribution, which adversely affects battery stability and lifespan. Utility Model Content

[0004] This utility model provides a terminal-type battery cell, including a housing, a cover plate, a battery cell winding body, and an electrolyte. The battery cell winding body and the electrolyte are disposed inside the housing. A positive terminal and a negative terminal are disposed on the cover plate, and the positive and negative terminals are insulated from the cover plate. The positive terminal of the battery cell winding body is connected to the positive terminal, and the negative terminal of the battery cell winding body is connected to the negative terminal. The terminal-type battery cell also includes an axially extending guide groove. The battery cell winding body is arranged around and closely attached to the guide groove. The guide groove is a cylindrical cavity. One end of the guide groove is directly connected to the cover plate, and the other end is directly connected to the bottom surface of the housing.

[0005] By placing a flow channel in the center of the cell winding, a central heat dissipation channel can be formed, which facilitates the flow of the cooling medium (gas or liquid) along the cell axis, enabling rapid heat conduction and resulting in a more uniform temperature rise inside the cell. This prevents heat from accumulating in the center of the cell, thereby reducing the risk of localized overheating. Compared with the external heat dissipation of traditional terminal-type cell structures, this cooling method is an internal cooling design, with a shorter heat conduction path and higher efficiency.

[0006] Furthermore, the existing pole-type battery cells have a hollow central space in the cell winding body, which is extremely unfavorable for heat dissipation. This design makes full use of the central space while effectively increasing the heat dissipation area of ​​the battery cell, improving the heat conduction path, and reducing the temperature gradient.

[0007] In existing designs, to ensure overall cell insulation, the cell winding body and the cover plate are connected by an insulating structure. This weakens the heat transfer between the cell and the cover plate, thus affecting the overall heat dissipation capacity of the terminal-type cell. The cell winding body in this invention has two heat transfer paths: one to the cover plate and the other to the heat dissipation channel. Furthermore, the cell winding body is positioned around and tightly against the heat dissipation channel, thus improving both insulation and overall cell heat dissipation capacity.

[0008] Preferably, the shell is a rectangular prism shell, the radius of the guide channel is r, the side length of the shell is a, and the height is H, all in mm, and satisfying 0.25≥2(2a+Πr) / (a 2 -Πr 2 )+2 / H≥0.05. When the terminal cell is a power cell, the ratio of the cell winding thickness to the guide groove diameter is selected from 2:1 to 0.6:1, 2(2a+Πr) / (a 2 -Πr 2 With a value of )+2 / H≥0.1, it is easier to meet the heat dissipation requirements of power-type terminal cells.

[0009] The ratio of the cell winding width to the guide groove diameter is selected from 2:1 to 0.6:1. This optimized ratio further improves heat dissipation efficiency. The ratio of the cell winding width to the guide groove diameter is precisely calculated to meet specific geometric conditions and ensure optimal heat dissipation performance. For example, if the ratio is too small, the guide groove diameter is large, and the area inside the cell near the guide groove dissipates heat faster, while the area away from the guide groove dissipates heat slower, resulting in a larger temperature difference. If the ratio is too large, the guide groove width is small, the heat dissipation capacity is insufficient, and the heat inside the cell is difficult to distribute evenly, which also leads to a larger temperature difference.

[0010] When the shell is a rectangular prism, the flow channel and the shell satisfy 2(2a+Πr) / (a 2 -Πr 2 When α+2 / H≥0.05, it can be ensured that the guide channel and shell are not simply increased in height or length, but that a good heat transfer geometry is maintained while keeping the volume; by reasonably controlling a 2 -Πr 2 This refers to the effective cooling boundary per unit heat-generating area, which improves heat dissipation capacity.

[0011] Preferably, the shell is a cylindrical shell, the radius of the guide channel is r, the height of the shell is H and the radius is R, and the radius of the guide channel is r, all in mm, and satisfying 2(R+r) / (R 2 -r 2 )+2 / H≥0.05.

[0012] When the shell is cylindrical, the flow channel and the shell satisfy 2(R+r) / (R 2 -r 2 When the condition is )+2 / H≥0.05, the guide groove has a good heat dissipation capacity per unit area, which is particularly beneficial for the uniform distribution of heat in the battery cell itself.

[0013] Preferably, the positive electrode post includes an outer connecting block and an inner connecting block, the outer connecting block and the inner connecting block are electrically connected, a first insulating elastic layer is provided between the outer connecting block and the cover plate, a second insulating elastic layer and an insulating plate are provided between the inner connecting block and the cover plate, and the insulating plate extends along the cover plate to the negative electrode post and makes the negative electrode post insulated from the cover plate.

[0014] The first and second insulating elastic layers are respectively disposed between the outer connecting block and the cover plate, and between the inner connecting block and the cover plate, further enhancing the insulation performance between the positive electrode post and the cover plate, preventing electrical connection between the positive electrode post and the cover plate, thereby avoiding short circuits. By setting an insulating elastic layer between the positive electrode post and the cover plate, the potential difference between the positive electrode post and the cover plate can be effectively reduced, reducing electrochemical corrosion and helping to improve the reliability and service life of the battery cell.

[0015] Preferably, the first insulating elastic layer extends to the four peripheral surfaces of the outer connecting block, and the height of the first insulating layer surrounding the four peripheral surfaces of the outer connecting block is 50% to 90% of the height of the outer connecting block. Setting the height of the first insulating layer to 50% to 90% of the height of the outer connecting block is a precisely calculated ratio that provides sufficient insulation protection without affecting the overall structural compactness and assembly efficiency of the battery cell due to excessive insulation layer height.

[0016] Preferably, the insulating plate has a hole through which the flow channel passes, and the insulating plate extends to the side of the inner connecting block, with the height of the insulating plate on the side equal to the height of the inner connecting block. The extension of the insulating plate to the side of the inner connecting block and its matching height ensure complete electrical isolation between the positive and negative terminals. By providing the hole through which the flow channel passes, the insulating plate effectively isolates the flow channel from other components of the battery cell, preventing arc discharge around the flow channel and thus improving the safety and reliability of the battery.

[0017] This utility model also discloses a battery pack, including the above-mentioned terminal cell, wherein a liquid cooling pipe is provided in the guide groove of the terminal cell, and the liquid cooling pipes of adjacent terminal cells are interconnected.

[0018] This utility model also discloses a battery pack, including the above-mentioned terminal cells, wherein the terminal cells are stacked axially, the guide grooves of adjacent terminal cells are connected end to end, and an air-cooling module is provided in the battery pack, wherein the air-cooling module generates cooling airflow and passes through the guide grooves of the terminal cells. Attached Figure Description

[0019] Figure 1 This is a perspective view of a terminal-type battery cell disclosed in this utility model;

[0020] Figure 2 This is a top view of a terminal-type battery cell disclosed in this utility model;

[0021] Figure 3 This is a bottom view of a pole-type battery cell disclosed in this utility model;

[0022] Figure 4 This is a cross-sectional view of the terminal portion of a terminal-type battery cell disclosed in this utility model;

[0023] Figure 5 This is a perspective view of another type of terminal cell disclosed in this utility model;

[0024] Among them, 1. shell, 11. bottom surface, 2. cover plate, 21. positive electrode post, 211. outer connecting block, 212. inner connecting block, 213. first insulating elastic layer, 214. second insulating elastic layer, 215. insulating plate, 22. negative electrode post, 3. guide groove, 31. opening. Implementation

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Example 1

[0027] like Figures 1-4As shown, this embodiment discloses a terminal-type battery cell, the structure of which includes a housing 1, a cover plate 2, a battery cell winding body, and an electrolyte. The battery cell winding body and the electrolyte are encapsulated together inside the housing 1. The cover plate 2 has a positive terminal 21 and a negative terminal 22, which are installed insulated from the cover plate 2. The positive terminal of the battery cell winding body is connected to the positive terminal 21 through a conductive connection, and the negative terminal is connected to the negative terminal 22. The battery cell also has a guide groove 3 extending along the axial direction, and the battery cell winding body is wound around the guide groove 3. The guide groove 3 has a cylindrical cavity structure, with one end opening 31 directly communicating with the cover plate 2, and the other end opening 31 connecting to the bottom surface 11 of the housing 1. The housing 1 adopts a square column design, and the radius of the guide groove 3 is set as r, the side length of the housing 1 is a, and the height is H, all in millimeters. To optimize heat dissipation performance while maintaining overall volume, its geometric parameters must meet the following conditions: the ratio of the width of the cell winding (located inside the housing 1 and closely configured with the housing 1, not shown in the attached figure) to the diameter of the guide groove 3 is 7.5, 2(2a+Πr) / (a 2 -Πr 2 )+2 / H=0.05.

[0028] The positive terminal 21 is composed of an outer connecting block 211 and an inner connecting block 212, which are electrically connected. A first insulating elastic layer 213 is provided between the outer connecting block 211 and the cover plate 2, while a second insulating elastic layer 214 and an insulating plate 215 are disposed between the inner connecting block 212 and the cover plate 2. The insulating plate 215 extends to the position of the negative terminal 22 and ensures electrical isolation between it and the cover plate 2.

[0029] To improve insulation and prevent electrical contact between the terminal block and the cover plate 2, a first insulating elastic layer 213 and a second insulating elastic layer 214 are respectively disposed between the outer connecting block 211 and the cover plate 2, and between the inner connecting block 212 and the cover plate 2. The first insulating elastic layer 213 extends further to the sides of the outer connecting block 211, with a surrounding height of 80% of the height of the outer connecting block 211, thus enhancing insulation while maintaining the compactness of the component.

[0030] In addition, the insulating plate 215 has a through hole that communicates with the guide groove 3 and extends to the side of the inner connecting block 212, with its height being the same as that of the inner connecting block 212. This structure provides sufficient insulation protection while avoiding the impact on assembly efficiency and overall structural compactness caused by excessive stacking of insulating materials.

[0031] Example 2

[0032] like Figure 5 As shown, the difference from Embodiment 1 is that the shell 1 is a cylindrical shell 1, the radius of the guide channel 3 is r, the height of the shell 1 is H and the radius is R, and the radius of the guide channel 3 is r, all in mm, and satisfying 2(R+r) / (R2 -r 2 )+2 / H=0.06.

[0033] Example 3

[0034] like Figure 5 As shown, the difference from Embodiment 1 is that the shell 1 is a cylindrical shell 1, the radius of the guide channel 3 is r, the height of the shell 1 is H and the radius is R, and the radius of the guide channel 3 is r, all in mm, and satisfying 2(R+r) / (R 2 -r 2 )+2 / H=0.1, the ratio of the thickness of the battery cell winding body to the diameter of the guide groove 3 is 2:1.

[0035] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the initial concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A terminal-type battery cell, comprising a housing, a cover plate, a battery cell winding body, and an electrolyte, wherein the battery cell winding body and the electrolyte are disposed within the housing, a positive terminal and a negative terminal are disposed on the cover plate, the positive terminal and the negative terminal are insulated from the cover plate, and the positive and negative terminals of the battery cell winding body are respectively connected to the positive terminal and the negative terminal, characterized in that: It also includes an axially extending guide groove, the battery cell winding body is arranged around and closely attached to the guide groove, the guide groove is a cylindrical cavity with openings at both ends, one end of the guide groove is directly connected to the cover plate, and the other end is directly connected to the bottom surface of the housing.

2. The electrode-type battery cell according to claim 1, characterized in that, The shell is a rectangular prism, the radius of the guide channel is r, the side length of the shell is a, and the height is H, all in mm, and satisfying 0.25≥2(2a+Πr) / (a 2 -Πr 2 )+2 / H≥0.

05.

3. The terminal-type battery cell according to claim 1, characterized in that, The shell is cylindrical, with a flow channel radius of r, a shell height of H and radius of R, and a flow channel radius of r, all in mm, and satisfying 0.15 ≥ 2(R + r) / (R 2 -r 2 )+2 / H≥0.

05.

4. The terminal-type battery cell according to claim 2, characterized in that, The ratio of the cell winding thickness to the guide groove diameter is selected from 2:1 to 0.6:1, and the guide groove and the shell satisfy 2(2a+Πr) / (a 2 -Πr 2 )+2 / H≥0.

1.

5. The terminal-type battery cell according to claim 1, characterized in that, The positive electrode post includes an outer connecting block and an inner connecting block, the outer connecting block and the inner connecting block are electrically connected, a first insulating elastic layer is provided between the outer connecting block and the cover plate, a second insulating elastic layer and an insulating plate are provided between the inner connecting block and the cover plate, and the insulating plate extends along the cover plate to the negative electrode post and makes the negative electrode post insulated from the cover plate.

6. The electrode-type battery cell according to claim 1, characterized in that, The first insulating elastic layer extends to the four peripheral surfaces of the outer connecting block, and the height of the first insulating layer surrounding the four peripheral surfaces of the outer connecting block is 50% to 90% of the height of the outer connecting block.

7. The terminal-type battery cell according to claim 1, characterized in that, The insulating plate is provided with a hole through which the flow guide groove passes, and the insulating plate extends to the side of the inner connecting block. The height of the insulating plate on the side is equal to the height of the inner connecting block.

8. A battery pack, characterized in that, Includes the terminal type battery cell as described in any one of claims 1-7, wherein the terminal type battery cells are stacked axially, and liquid cooling pipes are provided in the flow guide grooves of the terminal type battery cells, and the liquid cooling pipes of adjacent terminal type battery cells are interconnected.

9. A battery pack, characterized in that, The battery pack includes a terminal cell as described in any one of claims 1-7, wherein the terminal cells are arranged side by side, the guide grooves of adjacent terminal cells are connected end to end, and a cooling module is provided in the battery pack, wherein the cooling module generates cooling airflow that passes through the guide grooves of the terminal cells.

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