Waterproof structure of lithium ion battery pack

Abstract

The utility model belongs to the field of lithium ion batteries, and particularly relates to a waterproof structure of a lithium ion battery pack, which comprises a bottom shell, the bottom shell is provided with an assembling opening for packaging the lithium ion battery into the bottom shell mounting cavity; an upper cover for sealing the mounting cavity of the bottom shell is connected to the assembly opening of the bottom shell; a glue injection area is formed between the joint of the glue groove in the upper surface of the upper cover and the assembly opening of the bottom shell, and waterproof sealant is injected into the glue injection area. According to the waterproof structure of the lithium ion battery pack disclosed by the utility model, after the upper cover and the bottom shell are tightly assembled, glue is injected into a linking gap between the upper cover and the bottom shell, so that wet gas and liquid can be effectively and economically blocked, the overall air tightness performance is improved, a PVC (Polyvinyl Chloride) thermal shrinkage film in the original process is reduced, and the production cost is reduced. According to the battery pack, the available space in the mounting cavity of the bottom shell is increased, the overall size is reduced, the overall pouring sealant process in the battery pack is optimized, and direct control over the overall weight of a national standard vehicle and reduction of cost increase are facilitated.

Description

Technical Field

[0001] This utility model belongs to the field of lithium-ion batteries, specifically, it relates to a waterproof structure for a lithium-ion battery pack. Background Technology

[0002] The sealing structure of power batteries has a significant impact on their safety performance. Electric bicycles represent one of the main development trends of lithium-ion batteries, and their safety performance has attracted much attention from society.

[0003] Looking at all electric bicycle fires in recent years, water immersion accounts for as much as 10% of them. As the power source of an electric bicycle, the safety of the battery pack directly affects the overall safety of the vehicle. In particular, battery packs assembled under the pedals must meet at least the IP67 rating for dust and water resistance to ensure their waterproof sealing performance.

[0004] In the prior art, the battery pack shell and the top cover used to install lithium-ion battery packs are waterproofed by setting a sealing ring. However, since the sealing ring is not a completely fixed structure between the sealing ring and the battery pack shell and the top cover, gaps are prone to appear at the connection between the sealing ring and the battery pack shell and the top cover during actual use, resulting in leakage. The waterproof performance is unstable, which makes the battery pack easy to get wet and cause dangerous accidents.

[0005] In view of this, a waterproof structure for lithium-ion battery packs is proposed to address the problems mentioned above. Utility Model Content

[0006] The purpose of this invention is to solve the problems in the prior art and to propose a waterproof structure for lithium-ion battery packs.

[0007] The objective of this utility model is achieved through the following technical solution:

[0008] A waterproof structure for a lithium-ion battery pack includes: a bottom shell; an assembly port on the bottom shell for inserting the lithium-ion battery pack into the mounting cavity of the bottom shell; a top cover for sealing the mounting cavity of the bottom shell connected to the assembly port; and an injection area formed between the glue groove on the upper surface of the top cover and the assembly port of the bottom shell, wherein waterproof sealant is injected into the injection area.

[0009] Preferably, the top cover and the bottom shell assembly opening are connected by multiple fastening screws.

[0010] Preferably, the top cover is fitted into the retaining groove at the bottom shell assembly opening; multiple waterproof rivet nuts are pressed onto the side wall of the top cover, and multiple fastening screws pass laterally through the perforations and glue injection area of ​​the bottom shell side wall and are threaded into the internal threaded holes of the multiple waterproof rivet nuts.

[0011] Preferably, the connection between the first mounting hole and the charging port, and the connection between the second mounting hole and the discharging port are both coated with a waterproof adhesive layer.

[0012] Preferably, the waterproof adhesive layer is located on the side of the top cover near the mounting cavity of the bottom shell.

[0013] Preferably, both the bottom shell and the top cover are sheet metal shells.

[0014] Preferably, the upper surface of the cover is provided with a stainless steel spring handle.

[0015] Preferably, the waterproof sealant injected into the injection area is K-704NB silicone sealant.

[0016] Preferably, the BMS protection board, which is electrically connected to the lithium-ion battery pack, is located between the lithium-ion battery pack and the top cover.

[0017] Preferably, the inner wall of the bottom shell is provided with an anti-collision pad structure for interference fit with the lithium-ion battery pack.

[0018] This utility model has the following beneficial effects:

[0019] This utility model discloses a waterproof structure for a lithium-ion battery pack. After the top cover and bottom shell are tightly assembled, glue is injected into the joint between the top cover and the bottom shell. This effectively and economically blocks humid gases and liquids, ensuring improved overall airtightness. It reduces the amount of PVC heat-shrink film used in the original process, increases the usable space inside the bottom shell mounting cavity, and helps to reduce the overall size. It also optimizes the overall potting process inside the battery pack, which is more conducive to the direct control of the overall weight of national standard vehicles and reduces the increase in costs.

[0020] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the present invention. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0022] Figure 1 A perspective view of a waterproof structure for a lithium-ion battery pack provided in an embodiment of this utility model;

[0023] Figure 2 A top view of a waterproof structure for a lithium-ion battery pack provided in an embodiment of this utility model;

[0024] Figure 3 A cross-sectional view of a waterproof structure for a lithium-ion battery pack provided in an embodiment of this utility model. Figure 1 ;

[0025] Figure 4 A cross-sectional view of a waterproof structure for a lithium-ion battery pack provided in an embodiment of this utility model. Figure 2 ;

[0026] Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0027] Icons: 1. Charging port; 2. Discharging port; 3. Stainless steel spring handle; 4. Top cover; 5. Bottom shell; 6. Fastening screw; 7. Lithium-ion battery pack; 8. BMS protection board; 9. Waterproof press-fit nut post; 10. Waterproof sealant; 11. Glue injection area. Detailed Implementation

[0028] The following description and accompanying drawings fully illustrate specific embodiments described herein to enable those skilled in the art to practice them. Some embodiments may include or substitute parts and features of other embodiments. The scope of the embodiments herein includes the entire scope of the claims and all available equivalents thereof. Throughout this document, the terms “first,” “second,” etc., are used only to distinguish one element from another without requiring or implying any actual relationship or order between the elements. Indeed, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a structure, apparatus, or device. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the structure, apparatus, or device that includes said element. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments; similar or identical parts between embodiments can be referred to interchangeably.

[0029] The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used in this document to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings. They are used solely for the convenience of describing this document and for 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 this utility model. In the description herein, unless otherwise specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two elements; they can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0030] In this document, unless otherwise stated, the term "multiple" means two or more.

[0031] In this article, the character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0032] In this article, the term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0033] Where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0034] The following is in conjunction with the appendix Figure 1-5 The present invention will be described in further detail below.

[0035] like Figure 1-5 As shown, the present invention provides a waterproof structure for a lithium-ion battery pack, comprising: a bottom shell 5; an assembly port on the bottom shell 5 for inserting a lithium-ion battery pack 7 into the mounting cavity of the bottom shell 5; a top cover 4 for sealing the mounting cavity of the bottom shell 5 connected to the assembly port of the bottom shell 5; an injection area 11 is formed between the glue groove on the upper surface of the top cover 4 and the connection between the top cover 4 and the assembly port of the bottom shell 5, and waterproof sealant 10 is injected into the injection area 11.

[0036] This utility model discloses a waterproof structure for a lithium-ion battery pack. The bottom shell 5 has an assembly port for inserting the lithium-ion battery pack 7 into the mounting cavity of the bottom shell 5. After the lithium-ion battery pack 7 is inserted into the mounting cavity of the bottom shell 5, the top cover 4 is connected and installed at the assembly port of the bottom shell 5 by screws. After the top cover 4 and the bottom shell 5 are tightly assembled, an injection area 11 is formed between the glue groove on the upper surface of the top cover 4 and the connection between the top cover 4 and the assembly port of the bottom shell 5. Then, waterproof sealant 10 is injected into the injection area 11. After the waterproof sealant 10 is allowed to dry and harden, the entire battery pack can be packaged and shipped.

[0037] Applying adhesive to the joint between the top cover and the bottom shell can effectively and economically block humid gases and liquids, ensuring improved overall airtightness. This reduces the amount of PVC heat-shrink film used in the original process, increases the usable space inside the bottom shell mounting cavity, and reduces the overall size of the battery pack. It also optimizes the overall potting process inside the battery pack, which is more conducive to the direct control of the overall weight of national standard vehicles and reduces cost increases.

[0038] The upper cover 4 and the bottom shell 5 are connected by multiple fastening screws 6. The upper cover 4 is snapped into the retaining groove at the assembly opening of the bottom shell 5; multiple waterproof press-fit nut posts 9 are pressed onto the side wall of the upper cover 4, and the multiple fastening screws 6 pass laterally through the through holes and the glue injection area 11 on the side wall of the bottom shell 5, and are threaded into the internal thread holes of the multiple waterproof press-fit nut posts 9; the waterproof press-fit nut posts 9 are pressed onto the upper cover 4, and the bottom is sealed and integrally formed, with good stability; the structure of the waterproof press-fit nut posts 9 is detailed in [reference needed]. Figure 5 , Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0039] After the top cover 4 is secured in the retaining groove at the assembly opening of the bottom shell 5, multiple fastening screws 6 are passed laterally through the side wall perforations and the glue injection area 11 of the bottom shell 5, and threaded into the internal threaded holes of multiple waterproof press-fit nut pillars 9. This achieves a tight assembly and fixation between the top cover 4 and the bottom shell 5. The waterproof press-fit nut pillars 9 are made of 304 or 401 stainless steel, have M4 internal threaded holes and a sealed bottom, and are high in hardness, rust-proof, and waterproof. The tight assembly between the top cover 4 and the bottom shell 5 effectively blocks the path for humid gases and liquids to enter the battery pack. In addition, multiple The fastening screw 6 passes laterally through the perforation in the side wall of the bottom shell 5 and the glue injection area 11, and is threaded into the internal threaded holes of multiple waterproof press-fit nut pillars 9. The lateral arrangement can prevent the top cover 4 from sliding up and down at the assembly opening of the bottom shell 5 when the connection between the fastening screw 6 and the waterproof press-fit nut pillars 9 becomes loose, thus playing a limiting role and ensuring the stability of the assembly between the top cover 4 and the bottom shell 5. After the waterproof sealant 10 is injected into the glue injection area 11, the sealant solidifies on the multiple fastening screws 6 and the multiple waterproof press-fit nut pillars 9, further achieving locking and fixing and preventing loosening.

[0040] The top cover 4 is provided with a first mounting hole for installing the charging port 1 of the lithium-ion battery pack 7 and a second mounting hole for installing the discharging port 2 of the lithium-ion battery pack 7. The connection between the first mounting hole and the charging port 1, and the connection between the second mounting hole and the discharging port 2, are coated with a waterproof adhesive layer to seal the two connections and reduce the probability of leakage.

[0041] The waterproof adhesive layer is located on the side of the top cover 4 near the mounting cavity of the bottom shell 5 to prevent external impact or damage to the waterproof adhesive layer on the upper surface of the top cover 4, and further improve the sealing effect.

[0042] Both the bottom shell 5 and the top cover 4 are sheet metal shells with high structural strength and good stability, which can provide effective physical protection for the internal lithium-ion battery pack 7, such as anti-collision and waterproofing. Since sheet metal manufacturing allows for errors, there are gaps after the top cover 4 and the bottom shell 5 are fastened together, which facilitates the injection of adhesive.

[0043] The upper surface of the cover 4 is provided with a stainless steel spring handle 3, which makes it easy to lift the whole of this utility model. The material is 304 stainless steel, which has the advantage of rust prevention.

[0044] The waterproof sealant 10 injected into the injection area 11 is K-704NB silicone sealant. K-704NB silicone sealant 10 is used to inject sealant into the glue groove designed on the top cover 4, that is, to seal the gap that exists after the bottom shell 5 and the top cover 4 are assembled, so as to meet the waterproof and dustproof design requirements of the entire lithium-ion battery pack 7.

[0045] The lithium-ion battery pack 7 inside the bottom shell 5 meets usage requirements through single cells or multiple cells connected in series and parallel. The BMS protection board 8, electrically connected to the lithium-ion battery pack 7, is located between the lithium-ion battery pack 7 and the top cover 4. The BMS protection board 8 achieves safety protection by real-time detection and monitoring of the voltage, temperature, and current of individual lithium-ion cells or the entire battery pack module. The BMS protection board 8 is installed on the upper part of the lithium-ion battery pack 7, effectively protecting the lithium-ion battery pack 7.

[0046] This utility model provides a waterproof structure for a lithium-ion battery pack. Compared with the prior art, it uses a tight assembly of the upper cover 4 and the bottom shell 5, and then injects glue into the joint gap between the upper cover 4 and the bottom shell 5. This effectively and economically blocks humid gases and liquids, ensuring improved overall airtightness, reducing the direct control of the overall vehicle weight and reducing cost increases, which is more conducive to meeting national standards.

[0047] The specific advantages are as follows:

[0048] 1. Both the bottom shell 5 and the top cover 4 are sheet metal shells. Compared with traditional battery shells, the structure is optimized and the sheet metal bending process is simple. The top cover 4 is designed with bending grooves.

[0049] 2. The use of 4 glue grooves for sealing on the top cover reduces the amount of PVC heat shrink film used in the original process, thereby increasing the usable space in the mounting cavity of the bottom shell 5 and helping to reduce the overall size.

[0050] 3. The optimization of the overall potting process reduces the overall weight of the battery pack and production costs, which is more conducive to meeting the weight requirements of the national standard for electric bicycles.

[0051] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims.

[0052] This invention is not limited to the structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this invention is limited only by the appended claims.

Claims

1. A waterproof structure for a lithium-ion battery pack, characterized in that, include: Bottom shell (5); The bottom shell (5) is provided with an assembly port for inserting the lithium-ion battery pack (7) into the mounting cavity of the bottom shell (5); The assembly port of the bottom shell (5) is connected to an upper cover (4) for sealing the mounting cavity of the bottom shell (5); An injection area (11) is formed between the glue groove on the upper surface of the upper cover (4) and the assembly port of the bottom shell (5), and waterproof sealant (10) is injected into the injection area (11).

2. The waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, The top cover (4) and the bottom shell (5) are connected by multiple fastening screws (6).

3. The waterproof structure for a lithium-ion battery pack according to claim 2, characterized in that, The top cover (4) is fitted into the retaining groove at the assembly opening of the bottom shell (5); multiple waterproof rivet nut columns (9) are pressed onto the side wall of the top cover (4), and multiple fastening screws (6) pass laterally through the perforation and glue injection area (11) of the side wall of the bottom shell (5) and are threaded into the internal threaded holes of the multiple waterproof rivet nut columns (9).

4. The waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, The top cover (4) is provided with a first mounting hole for installing the charging port (1) of the lithium-ion battery pack (7) and a second mounting hole for installing the discharging port (2) of the lithium-ion battery pack (7).

5. A waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, Waterproof adhesive is applied to the connection between the first assembly hole and the charging port (1) and the connection between the second assembly hole and the discharging port (2).

6. A waterproof structure for a lithium-ion battery pack according to claim 5, characterized in that, The waterproof adhesive layer is located on the side of the top cover (4) near the mounting cavity of the bottom shell (5).

7. A waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, Both the bottom shell (5) and the top cover (4) are sheet metal shells.

8. A waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, The upper surface of the cover (4) is provided with a stainless steel spring handle (3).

9. A waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, The waterproof sealant (10) injected into the injection area (11) is K-704NB silicone sealant.

10. A waterproof structure for a lithium-ion battery pack according to claim 1, characterized in that, The BMS protection board (8), which is electrically connected to the lithium-ion battery pack (7), is located between the lithium-ion battery pack (7) and the top cover (4).

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