Power battery and plastic structure thereof

Abstract

The utility model discloses a kind of power battery and its lower plastic structure, lower plastic structure includes lower plastic body, lower plastic body has first surface and second surface of back direction, lower plastic body is equipped with the pole post through hole of first surface and second surface, first surface is equipped with the positioning boss of coaxial arrangement with pole post through hole, second surface is arranged with elastic column around pole post through hole at intervals.The above-mentioned power battery and its lower plastic structure, positioning boss can realize the positioning of lower plastic structure, it is convenient to fix when assembling.Lower plastic body is clamped by elastic column and pole post terminal, avoid lower plastic structure by hot melting process and top cover piece connection, lower plastic due to thermal expansion and contraction dimensional deviation can cause with cover plate misassembly problem.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a power battery and its underlying plastic structure. Background Technology

[0002] Due to their advantages such as high energy density, high power density, high cycle life, and long storage time, power batteries (such as lithium-ion batteries) have been widely used in portable electronic devices such as mobile phones, digital cameras, and laptops. They also have broad application prospects in electric vehicles, electric bicycles, and other electric transportation vehicles, as well as large and medium-sized electric equipment such as energy storage facilities, becoming a key to solving global problems such as the energy crisis and environmental pollution.

[0003] A power battery generally consists of a cell, a casing that houses the cell, and a top cover that is sealed onto the casing. The top cover, as an important component of the power battery, typically includes a top cover plate, a positive terminal, a negative terminal, an upper plastic layer, and a lower plastic layer. The lower plastic layer plays a primary insulating role between the top cover plate and the cell.

[0004] Currently, the traditional lower plastic structure is connected to the top cover plate via a hot-melt process. This hot-melt process requires precise dimensional accuracy of the lower plastic hot-melt column and careful control of ambient temperature. Because the lower plastic is made of plastic, it exhibits thermal expansion and contraction; dimensional deviations can cause misalignment during assembly with the cover plate. Utility Model Content

[0005] Therefore, it is necessary to address the problem that the traditional method of connecting the lower plastic structure to the top cover plate via a hot-melt process can cause misalignment during assembly due to thermal expansion and contraction of the lower plastic. A new power battery and its lower plastic structure should be provided.

[0006] A lower plastic structure includes: a lower plastic body having a first surface and a second surface facing away from each other; the lower plastic body having a through hole for poles penetrating the first surface and the second surface; the first surface having a positioning boss arranged coaxially with the through hole for poles; and the second surface having elastic posts arranged at intervals around the through hole for poles.

[0007] In one embodiment, the lower plastic body is provided with a liquid injection hole penetrating the first surface and the second surface.

[0008] In one embodiment, a support is installed inside the injection hole.

[0009] In one embodiment, the injection holes are provided in two sets, and the two sets of injection holes are spaced apart on a straight line formed by the two sets of electrode through holes.

[0010] In one embodiment, the second surface of the lower plastic body is provided with a central protrusion and two end protrusions, the two end protrusions being located at both ends of the lower plastic body, and the central protrusion being located between the two end protrusions.

[0011] In one embodiment, the central protrusion is provided with a vent hole that penetrates the lower plastic body.

[0012] In one embodiment, a venting groove is formed on the first surface of the lower plastic body in the area directly opposite the central protrusion, the vent hole penetrates the sidewall of the venting groove, and a reinforcing structure is provided inside the venting groove.

[0013] In one embodiment, the end protrusion includes a frame structure mounted on the second surface, wherein support plates are spaced apart within the frame structure.

[0014] In one embodiment, the elastic post includes a connecting portion perpendicular to the second surface and an extension portion connected to the connecting portion and extending away from the post through hole.

[0015] A power battery, comprising:

[0016] The lower plastic structure as described in any of the above.

[0017] The aforementioned power battery and its underlying plastic structure have at least the following advantages:

[0018] During battery cover assembly, the terminal blocks are inserted into the through holes of the lower plastic body. Elastic post clamps engage with the terminal blocks, and positioning bosses are inserted into the terminal block holes of the top cover, securing the terminal blocks to the top cover. The positioning bosses position the lower plastic structure, facilitating assembly. The lower plastic body engages with the terminal blocks via elastic posts, while the terminal blocks are fixedly connected to the top cover, thus achieving assembly of the lower plastic body and the top cover. This avoids the misalignment issues that can occur with the lower plastic structure when connected to the top cover via a hot-melt process, where thermal expansion and contraction could cause dimensional deviations in the lower plastic assembly. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of this utility model, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0020] Figure 1 This is a schematic diagram of the lower plastic structure in one embodiment;

[0021] Figure 2 for Figure 1 The top view of the plastic structure shown below;

[0022] Figure 3 for Figure 2 Sectional view of line AA in the middle;

[0023] Figure 4 for Figure 3 A magnified view of a section at point A in the middle;

[0024] Figure 5 for Figure 1 The diagram below shows a structural schematic of the plastic structure from another perspective.

[0025] Figure label:

[0026] 10-Lower plastic body, 101-First surface, 102-Second surface, 11-Pole post through hole, 12-Positioning boss, 13-Elastic main body, 131-Connecting part, 132-Extension part, 14-Injection hole, 141-Support, 15-End protrusion, 151-Frame structure, 152-Support plate, 16-Middle protrusion, 161-Vent hole, 162-Ventilation groove, 17-Reinforcing structure, 171-First reinforcing rib, 172-Second reinforcing rib. Detailed Implementation

[0027] To make the above-mentioned objectives, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right guide," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0030] Please see Figure 1One embodiment of the lower plastic structure includes a lower plastic body 10, which is a single sheet with a sheet-like structure. Its specific structure is not fixed and is adjusted for suitability based on the specific design of different batteries. For example, the lower plastic body 10 can be a narrow / long strip structure, or it can be made into a square or round shape, etc. The material of the lower plastic body 10 can be polypropylene (PP) or polyphenylene sulfide (PPS), etc.

[0031] For ease of understanding of the technical solution of this application, Figure 1 For example, in this application, the length direction of the lower plastic body 10 is set as the X direction, the width direction of the lower plastic body 10 is set as the Y direction, and the thickness direction of the lower plastic body 10 is set as the Z direction.

[0032] Please refer to the following: Figure 2 and Figure 3 The lower plastic body 10 has a first surface 101 and a second surface 102 facing away from each other along the thickness direction. During battery assembly, the surface of the lower plastic body 10 that mates with the top cover is the first surface 101, and the surface of the lower plastic body 10 that mates with the battery cell is the second surface 102. The lower plastic body 10 is provided with terminal through holes 11 penetrating the first surface 101 and the second surface 102, for mounting terminal terminals. Two sets of terminal through holes 11 are provided, spaced apart along the length of the lower plastic body 10, for respectively mounting positive and negative terminal terminals.

[0033] Please refer to the following: Figure 4 The first surface 101 is provided with a positioning boss 12, which is coaxially arranged with the pole post through hole 11. The second surface 102 is provided with elastic posts 13 spaced apart around the pole post through hole 11. That is, the positioning boss 12 and the elastic posts 13 are located at the two end faces of the pole post through hole 11, respectively. In one embodiment, the sidewall of the elastic post 13 is flush with the sidewall of the pole post through hole 11, and a plurality of elastic posts 13 are evenly spaced along the circumferential direction of the pole post through hole 11.

[0034] During battery assembly, the positioning boss 12 is inserted into the terminal hole of the top cover to position the lower plastic body 10. The elastic post 13 deforms elastically under the action of the terminal, clamping onto the outside of the terminal to achieve a snap-fit ​​fixation. The terminal is fixedly connected to the top cover, thus assembling the lower plastic body 10 with the top cover. This avoids the problem of misalignment during assembly caused by thermal expansion and contraction of the lower plastic structure when connected to the top cover via a hot-melt process. Simultaneously, the snap-fit ​​between the elastic post 13 and the terminal avoids gap issues between the terminal and the elastic post 13 caused by tolerance zones.

[0035] In one embodiment, the elastic post 13 includes a connecting portion 131 perpendicular to the second surface 102, and an extension portion 132 connected to the connecting portion 131 and extending away from the electrode through hole 11. The extension portion 132 of the elastic post 13 extends away from the electrode through hole 11, facilitating insertion of the electrode terminal into the electrode through hole 11 and allowing the elastic post 13 to clamp and fix the electrode terminal outside the electrode. An arc-shaped transition portion is provided between the connecting portion 131 and the extension portion 132, which guides the electrode terminal into the electrode through hole 11.

[0036] Please see Figure 1 and Figure 5 In one embodiment, the lower plastic body 10 is provided with an injection hole 14 penetrating the first surface 101 and the second surface 102. Electrolyte can be injected into the battery casing through the injection hole 14, allowing the electrolyte to wet the battery cell assembly. A support 141 is installed inside the injection hole 14. The support 141 can prevent components such as the sealing cap of the injection hole 14 from falling into the battery cell assembly and affecting the subsequent operation of the battery cell assembly.

[0037] In one embodiment, two sets of injection holes 14 are provided, and the two sets of injection holes 14 are arranged on a straight line formed by the two sets of electrode through holes 11. The design of two sets of injection holes 14 serves to prevent mistaken assembly. Specifically, in this embodiment, the two sets of electrode through holes 11 are located on the center line of the length direction of the lower plastic body 10, therefore the two sets of injection holes 14 are also located on the center line of the length direction of the lower plastic body 10. Further, the injection holes 14 are arranged between the electrode through holes 11 and the center line of the width direction of the lower plastic body 10.

[0038] In one embodiment, the second surface 102 of the lower plastic body 10 is provided with a central protrusion 16 and two end protrusions 15. The two end protrusions 15 are located at both ends of the lower plastic body 10, and the central protrusion 16 is located between the two end protrusions 15. The end protrusions 15 press against and support the battery cell assembly, while the height of the central protrusion 16 is less than the height of the end protrusions 15, so as to be spaced apart from the battery cell assembly.

[0039] In one embodiment, the central protrusion 16 is provided with a vent hole 161 penetrating the lower plastic body 10 to facilitate internal pressure relief and air release. Furthermore, a vent groove 162 is formed in the area of ​​the first surface 101 of the lower plastic body 10 directly opposite the central protrusion 16, so that the thickness of the portion of the lower plastic body 10 where the central protrusion 16 is located is the same as the thickness of other areas, and the vent hole 161 penetrates the sidewall of the vent groove 162.

[0040] In one embodiment, the central protrusion 16 is centrally located and extends along the centerline of the lower plastic body 10 in the width direction. The vent 161 is a strip-shaped hole that extends along the width direction of the lower plastic body 10.

[0041] Furthermore, two sets of vent holes 161 are provided, and the two sets of vent holes 161 are symmetrically arranged about the center line of the width direction of the lower plastic body 10. Each set of vent holes 161 has two vent holes 161, and the two vent holes 161 are arranged at intervals along the center line of the width direction of the lower plastic body 10.

[0042] In one embodiment, a reinforcing structure 17 is provided within the venting groove 162. The reinforcing structure 17 provides support to the inner wall of the venting groove 162, increasing the structural strength of the lower plastic and preventing dimensional changes due to thermal expansion and contraction. Specifically, the reinforcing structure 17 includes a first reinforcing rib 171 and a second reinforcing rib 172. The first reinforcing rib 171 extends along the length direction of the lower plastic body 10, and the second reinforcing rib 172 extends along the width direction of the lower plastic body 10. The reinforcing structure 17 provides support in both the length and width directions, ensuring the strength of the lower plastic.

[0043] In one embodiment, the end protrusion 15 includes a frame structure 151 mounted on the second surface 102. Support plates 152 are spaced within the frame structure 151, providing support for the frame structure 151 and preventing deformation of the end protrusion 15 under stress. The end protrusion 15 is an open frame structure 151, with no holes penetrating the lower plastic body 10. Therefore, the surface of the lower plastic body 10 in contact with the top cover is solid, preventing the contents of the battery cell from being trapped.

[0044] On the other hand, the present invention also provides a power battery, including the lower plastic structure of any of the above embodiments.

[0045] The aforementioned power battery and its lower plastic structure are assembled onto the top cover via positioning bosses 12 and elastic pillars 13. This facilitates positioning and fixation during assembly, avoiding the misalignment issues that can occur when the lower plastic structure is connected to the top cover via a hot-melt process due to thermal expansion and contraction. It also avoids gaps caused by tolerance zones. The lower plastic body 10 has two injection holes 14, which serve as a foolproof feature during assembly. A reinforcing structure 17 is incorporated within the vent groove 162 to increase structural strength and prevent dimensional deformation due to thermal expansion and contraction. Symmetrical vent holes 161 are designed on the central protrusion 16 for internal pressure relief and venting. The end protrusions 15 form an open frame, and the contact surface between the lower plastic body 10 and the top cover is solid, preventing the contents of the battery cell from becoming trapped.

[0046] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model, and they should all be covered within the scope of the claims and specification of this utility model.

Claims

1. A lower plastic structure, characterized in that, include: The device includes a lower plastic body, which has a first surface and a second surface facing away from each other. The lower plastic body is provided with an electrode through hole that penetrates the first surface and the second surface. The first surface is provided with a positioning boss arranged coaxially with the electrode through hole. The second surface is provided with elastic posts arranged at intervals around the electrode through hole.

2. The lower plastic structure according to claim 1, characterized in that, The lower plastic body is provided with a liquid injection hole that penetrates the first surface and the second surface.

3. The lower plastic structure according to claim 2, characterized in that, A support is installed inside the injection hole.

4. The lower plastic structure according to claim 2, characterized in that, The injection holes are provided in two sets, and the two sets of injection holes are spaced apart on a straight line formed by the two sets of electrode through holes.

5. The lower plastic structure according to claim 1, characterized in that, The second surface of the lower plastic body is provided with a central protrusion and two end protrusions. The two end protrusions are located at both ends of the lower plastic body, and the central protrusion is located between the two end protrusions.

6. The lower plastic structure according to claim 5, characterized in that, The central protrusion is provided with a vent hole that penetrates the lower plastic body.

7. The lower plastic structure according to claim 6, characterized in that, A venting groove is formed on the first surface of the lower plastic body and in the area directly opposite the central protrusion. The vent hole penetrates the side wall of the venting groove, and a reinforcing structure is provided inside the venting groove.

8. The lower plastic structure according to claim 5, characterized in that, The end protrusion includes a frame structure mounted on the second surface, and the frame structure is provided with support plates spaced apart within it.

9. The lower plastic structure according to claim 1, characterized in that, The elastic post includes a connecting portion perpendicular to the second surface, and an extension portion connected to the connecting portion and extending away from the pole post through hole.

10. A power battery, characterized in that, include: The lower plastic structure as described in any one of claims 1-9.

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