A waterproof structure for a lithium battery box of an electric low-speed vehicle

Abstract

The utility model discloses a waterproof structure for electric low -speed car lithium cell box belongs to lithium cell box technical field, and this structure includes the battery box of placing electric core, and there is sealed box cover on the battery box, and the opening of battery box is provided with the plug -in part, and the inner wall all around of plug -in part is provided with extruded steel strip, and the sealed layer is arranged between extruded steel strip and plug -in part, and the outside of sealed box cover is provided with a plurality of fastening bolts, and a plurality of through -going holes opposite fastening bolt are provided on plug -in part, and fastening bolt passes plug -in part and is screwed down with extruded steel strip, and through the combination structure of plug -in part, high density bubble cotton and extruded steel strip, drive extruded steel strip to move to sealed box cover inner wall with the screwing of fastening bolt, form steady clamping force to high density bubble cotton, and the accurate compression rate of 40% of bubble cotton is matched, can realize the close sealing not only to avoid the aging of bubble cotton caused by excessive compression, but also to block the moisture infiltration path from the structure level.

Description

Technical Field

[0001] This utility model belongs to the field of lithium battery box technology, specifically, it relates to a waterproof structure for lithium battery boxes used in electric low-speed vehicles. Background Technology

[0002] Lithium batteries are batteries that use lithium metal or lithium alloy as the positive or negative electrode material and a non-aqueous electrolyte solution. In electric vehicle applications, lithium batteries specifically refer to lithium-ion battery packs, which serve as a power source to store electrical energy and drive electric motors. They are commonly found in electric bicycles, electric motorcycles, and electric tricycles.

[0003] Current mainstream lithium batteries use materials such as sealing rings, waterproof silicone, and waterproof tape to achieve an IPX4 or higher waterproof rating, which can withstand short periods of light rain.

[0004] However, the performance of waterproof materials gradually declines with prolonged use, leading to aging and failure. In damp environments such as long-term rain or immersion in water, equipment is highly susceptible to water ingress, which not only negatively impacts normal operation but also poses serious safety hazards. The specific impacts are as follows:

[0005] Core functions are impaired: The device's battery life will be significantly reduced, making it unable to meet normal usage needs; at the same time, the charging system is susceptible to moisture interference, resulting in problems such as charging difficulties and charging interruptions, which directly affect the device's usability.

[0006] Internal component corrosion: Even if the surface appears dry, residual moisture that seeps into the equipment will continue to react with the metal components, causing corrosion, performance degradation, and shortening the overall service life of the equipment.

[0007] Safety risks increase dramatically: When water comes into contact with the internal circuitry, it may cause short circuits or even spontaneous combustion. In particular, for batteries, thermal runaway is easily triggered during charging after water gets in. According to data, the failure rate will soar at this time, and in severe cases, it may cause the battery to explode, posing a major threat to personal and property safety. Utility Model Content

[0008] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0009] To address the issue that the performance of waterproof materials mentioned in the background technology gradually declines with increasing usage time, leading to aging and failure, and that equipment is prone to water ingress in humid environments such as prolonged rain or immersion, which not only has multiple negative impacts on the normal operation of the equipment but also poses serious safety hazards, this utility model adopts the following technical solution.

[0010] A waterproof structure for a lithium battery box in an electric low-speed vehicle includes a battery box for holding battery cells, an opening at the top of the battery box, a sealing cover at the opening, a connector at the opening of the battery box, extruded steel strips around the inner wall of the connector, a sealing layer between the extruded steel strips and the connector, the sealing cover covering the outside of the connector, multiple fastening bolts on the outside of the sealing cover, multiple through holes on the connector corresponding to the fastening bolts, the fastening bolts passing through the connector and threadedly connected to the extruded steel strips, and rotation of the fastening bolts pulling the extruded steel strips toward the inner wall of the sealing cover to compress the sealing layer.

[0011] Preferably, each extruded steel bar is provided with multiple insertion posts, each insertion post is provided with a threaded hole, the threaded hole and the through hole are positioned correspondingly, and the fastening bolt is threadedly connected to the threaded hole.

[0012] Preferably, it also includes a sealing layer provided on the outer wall of the plug-in portion, which is pressed against the outer wall of the plug-in portion when the sealing cover is plugged into the plug-in portion.

[0013] Preferably, the sealing layer on both sides of the outer wall of the plug is integrally formed, and the cross-section of the sealing layer is U-shaped. The opening of the sealing layer is inserted into the outside of the plug. After the sealing box cover is installed, the three sides of the sealing layer are squeezed and sealed.

[0014] Preferably, a bending portion is provided between the battery box and the plug-in portion, and the bending portion and the plug-in portion form a 90° angle, with the bottom of the sealing cover fitting against the upper end of the bending portion.

[0015] Preferably, the sealing layer is high-density foam with a thickness of 2-5 mm.

[0016] Preferably, the sealing layer is adhered to the outside of the connector using a high-viscosity adhesive.

[0017] Preferably, the surfaces of the battery box, the sealed lid, and the extruded steel strip are coated with epoxy resin waterproof coating or galvanized after cleaning.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] 1. Through the combined structure of the plug-in part, high-density foam, and extruded steel strip, the extruded steel strip is driven to move towards the inner wall of the sealing box by the tightening of the fastening bolts, forming a stable clamping force on the high-density foam. Combined with the precise compression rate of 35% to 40% of the foam, it not only avoids foam aging caused by over-compression, but also achieves a tight seal, blocking the path of water infiltration from the structural level. At the same time, the corresponding design of the through hole and the plug-in post, as well as the sealing treatment of the weld, further eliminate the risk of water seepage at the bolt connection, build a basic waterproof barrier, and make the waterproof effect better.

[0020] 2. High-density foam is added to the outer wall of the connector to allow the foam on both sides of the connector to be squeezed simultaneously when the sealed cover is plugged into the battery box, forming a double seal and doubling the waterproof reliability.

[0021] 3. The foam on both sides is optimized into a U-shaped one-piece molding structure, which allows the three outer walls of the foam to fully contact and be compressed with the sealing box cover, greatly increasing the sealing area and further reducing the probability of moisture breaking through the sealing layer.

[0022] 4. By folding the inward-facing part at a 90° angle to the insertion part, the contact area between the sealing cover and the battery box is increased, enhancing the sealing effect in terms of structural fit. Each embodiment forms a progressive waterproof system of basic sealing, double sealing, multi-faceted sealing, and enhanced surface sealing, resulting in better waterproof performance. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a waterproof structure for a lithium battery box in an electric low-speed vehicle according to the present invention.

[0024] Figure 2 This is a schematic diagram of the assembly structure of the middle box cover of this utility model;

[0025] Figure 3 This is a schematic diagram of the exploded structure of the battery box in this utility model;

[0026] Figure 4 In this utility model Figure 3 Enlarged structural diagram at point A in the middle;

[0027] Figure 5 In this utility model Figure 3 Enlarged structural diagram at point B;

[0028] Figure 6 This is a top-down view of the exploded battery box structure in this utility model.

[0029] The correspondence between the labels and component names in the attached figures is as follows:

[0030] 100. Battery box; 101. Connector; 102. Through hole; 103. Bending part;

[0031] 200. Sealing box cover; 201. Fastening bolts;

[0032] 300. High-density foam; 301. Extruded steel strip; 302. Insert post; 303. Threaded hole. Detailed Implementation

[0033] 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.

[0034] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0035] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments. The present invention provides the following embodiments.

[0036] Example 1

[0037] like Figure 1-3The diagram shows a preferred embodiment of the waterproof structure for a lithium battery box in an electric low-speed vehicle. This embodiment includes a battery box 100 with an opening, a sealing cover 200 at the top, and a fastening bolt 201 to fix the sealing cover 200 to the battery box 100. A connector 101 with a height of 5-8 mm is provided at the opening of the battery box 100. The inner wall of the sealing cover 200 contacts the outer wall of the connector 101 during insertion. High-density foam 300 is adhered to the inner wall of the connector 101 using high-viscosity adhesive. An extruded steel strip 301 is attached to the outside of the high-density foam 300, and multiple insertion posts 302 are provided on the extruded steel strip 301. Each insertion post 302... 2. A threaded hole 303 is provided on the part, and the plug-in post 302 is welded to the extruded steel strip 301 by welding. The weld is sealed. The plug-in part 101 is provided with multiple through holes 102 opposite to the plug-in post 302. After the sealing box cover 200 is plugged into the battery box 100, each fastening bolt 201 corresponds to the position of each threaded hole 303. The fastening bolt 201 passes through the plug-in part 101 and is connected to the internal thread of the plug-in post 302. When the sealing box cover 200 rotates, on the one hand, the sealing box cover 200 can be fixed to the battery box 100 through the plug-in part 101. On the other hand, the extruded steel strip 301 can be moved towards the inner wall of the sealing box cover 200, thereby clamping the high-density foam 300 with a compression rate of 35-50%, forming an effective seal and increasing the waterproof effect.

[0038] Among them, the plug post 302 can be a waterproof nut post.

[0039] The battery box 100, the sealing cover 200, and the extruded steel strip 301 are all made of cold-rolled steel plate. The internal dimensions of the battery box 100 are designed according to the battery size and the installation space of the electric vehicle. The inner dimensions of the sealing cover 200 match the dimensions of the plug-in part 101 to ensure that the sealing cover 200 can cover the outside of the plug-in part 101.

[0040] The length of the extruded steel strip 301 corresponds to the length of the inner wall of the insertion part 101. The high-density foam 300 is made of closed-cell foaming materials such as EVA cotton, with a thickness of 2-5mm. Before pasting, the pasting surface needs to be cleaned to remove oil and impurities to ensure a firm bond. In this embodiment, the preferred size of the high-density foam 300 is 3mm. After assembly, the compression rate is 40%, which ensures a good sealing effect without causing premature aging and failure of the foam due to excessive compression.

[0041] The battery box 100, the sealing cover 200, and the extruded steel strip 301 are all waterproofed. The specific treatment method is as follows: first, phosphating is performed to remove the surface oxide layer, and then an epoxy resin waterproof coating with a thickness of 60-80μm is sprayed evenly, or galvanizing is performed with a zinc layer thickness of not less than 8μm, in order to improve the corrosion resistance and waterproof performance of the overall structure.

[0042] Example 2

[0043] like Figure 3 As shown, this is another preferred embodiment of the present invention. The difference between this embodiment and embodiment 1 is that the outer wall of the plug-in part 101 is also covered with high-density foam 300 by high-viscosity adhesive. When the sealing cover 200 is plugged into the battery box 100, the high-density foam 300 on both sides of the plug-in part 101 can be squeezed and sealed at the same time, achieving the effect of double sealing, which makes the battery cells inside the battery box 100 have a longer service life.

[0044] Example 3

[0045] like Figure 6 As shown, this is another preferred embodiment of the present invention. The difference between this embodiment and embodiment 2 is that the high-density foam 300 on both sides of the insertion part 101 is integrally formed, and the cross-section of the high-density foam 300 is U-shaped. The opening of the high-density foam 300 is stuck on the outer wall of the insertion part 101. Through the U-shaped setting, when the sealing cover 200 is inserted into the battery box 100, all three outer wall surfaces of the high-density foam 300 can be squeezed by the sealing cover 200, further increasing the sealing effect.

[0046] Example 4

[0047] like Figure 4 As shown, this is another preferred embodiment of the present invention. The difference between this embodiment and embodiments 1-3 is that a bending portion 103 is provided between the battery box 100 and the plug-in portion 101. The bending portion 103 is folded inward from the top of the battery box 100, and the plug-in portion 101 and the bending portion 103 form a 90° angle. The bending portion 103 increases the contact surface when the sealing cover 200 is plugged into the battery box 100, resulting in a better sealing effect.

[0048] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present utility model. It should not be construed that the specific implementation of the present utility model is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present utility model, and all such deductions or substitutions should be considered to fall within the scope of protection defined by the claims submitted by the present utility model.

Claims

1. A waterproof structure for a lithium battery box in an electric low-speed vehicle, comprising a battery box (100) for holding battery cells, an opening at the top of the battery box (100), and a sealing cover (200) at the opening, characterized in that, The battery box (100) has an opening with a plug-in part (101). The inner wall of the plug-in part (101) is surrounded by extruded steel strips (301). A sealing layer is provided between the extruded steel strips (301) and the plug-in part (101). A sealing box cover (200) covers the outside of the plug-in part (101). Multiple fastening bolts (201) are provided on the outside of the sealing box cover (200). Multiple through holes (102) are provided on the plug-in part (101) opposite to the fastening bolts (201). The fastening bolts (201) pass through the plug-in part (101) and are threadedly connected to the extruded steel strips (301). The rotation of the fastening bolts (201) pulls the extruded steel strips (301) toward the inner wall of the sealing box cover (200) to press the sealing layer.

2. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to claim 1, characterized in that, Each extruded steel bar (301) is provided with multiple plug-in pins (302), and each plug-in pin (302) is provided with a threaded hole (303). The threaded hole (303) corresponds to the position of the through hole (102), and the fastening bolt (201) is threadedly connected to the threaded hole (303).

3. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to claim 1, characterized in that, It also includes a sealing layer provided on the outer wall of the plug-in part (101), which is pressed against the sealing layer on the outer wall of the plug-in part (101) when the sealing cover (200) is plugged into the plug-in part (101).

4. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to claim 3, characterized in that, The sealing layer on both sides of the plug-in part (101) is integrally formed, and the cross-section of the sealing layer is U-shaped. The opening of the sealing layer is inserted into the outside of the plug-in part (101). After the sealing box cover (200) is installed, it squeezes and seals the three sides of the sealing layer.

5. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to claim 1, characterized in that, A bending part (103) is provided between the battery box (100) and the plug-in part (101), and the bending part (103) and the plug-in part (101) are at a 90° angle. The bottom of the sealing cover (200) is attached to the top of the bending part (103).

6. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to claim 1, characterized in that, The sealing layer is made of high-density foam (300), and the thickness of the high-density foam (300) is 2-5mm.

7. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to any one of claims 1-6, characterized in that, The sealing layer is attached to the outside of the plug part (101) using high-viscosity adhesive.

8. The waterproof structure for a lithium battery box in an electric low-speed vehicle according to claim 1, characterized in that, The surfaces of the battery box (100), the sealed box cover (200), and the extruded steel strip (301) are sprayed with epoxy resin waterproof coating or galvanized after cleaning.

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