Battery module

Abstract

The application discloses a battery module, which comprises two or more battery cells connected by a gasket, wherein the battery cell comprises a cover plate and an electrode, the electrode comprises a main body and a connecting part; the main body is at least partially arranged in a through hole of the cover plate, one end of the main body is connected with a tab of a pole group in the battery cell, and the other end of the main body is connected with the connecting part; the connecting part is clamped and limited with the outer side of the cover plate; the gasket is arranged on the top surface of the connecting part and is fixedly connected with the top surface through a fastener. Thus, the gasket and the connecting part of the electrode are not welded, and the high temperature in the welding process can be avoided to have adverse effects on the battery cell including the first insulating part.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery module. Background Technology

[0002] In the battery manufacturing process, multiple cells (also known as single cells) are often connected in series or parallel to meet specific voltage and capacity requirements. Reliable connections between cells are one of the key factors in ensuring the efficient and stable operation of the entire battery pack.

[0003] In some products, battery cells are connected by welding tabs. Each cell's terminal or connecting block at its outer end is welded to a tab, thus establishing the connection between cells. It's important to note that a tab is a large-section conductive strip or plate used for connection, typically made of highly conductive materials such as copper or aluminum. Their function is to establish a reliable current transmission path between different cells, ensuring efficient current flow without excessive energy loss or heat generation.

[0004] However, in practice, the welding process typically involves localized heating to melt the two metal components (i.e., the electrode plate and the outer end of the terminal, or the electrode plate and the connecting block located at the outer end of the terminal) to bond them together. Temperatures near the welding point can reach hundreds of degrees Celsius or even higher. Most battery cells use an upper plastic layer close to the electrode plate, and this upper plastic layer is generally made of polypropylene (PP), polyethylene (PE), or other types of thermoplastics. While these materials have good mechanical strength and chemical stability, their heat resistance is limited. They soften when approaching or exceeding their glass transition temperature, potentially leading to deformation or damage, affecting appearance quality and installation accuracy. Furthermore, uneven cooling after welding can cause micro-cracks on the surface of the upper plastic layer, weakening its overall strength. In more severe cases, the high temperatures of the welding process can burn the outer protective material of the battery cell (especially the upper plastic layer between the connecting block and the cover plate), affecting the resistance at that location and even causing insulation failure, increasing the risk of short circuits. Utility Model Content

[0005] In view of this, the purpose of this application is to provide a battery module that avoids the adverse effects of high temperatures during the welding process on the battery cell (especially the insulating parts near the electrodes).

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] A battery module includes two or more battery cells, wherein the different battery cells are connected by a tab, wherein:

[0008] The battery cell includes a cover plate and electrodes, and the electrodes include a main body and a connecting part;

[0009] The main body is at least partially inserted through the through hole of the cover plate, with one end connected to the electrode tab of the electrode group located in the battery cell, and the other end connected to the connecting part;

[0010] The connecting part is engaged and limited by the outer side of the cover plate;

[0011] The plate is located on the top surface of the connecting part and is fixedly connected to the top surface by fasteners.

[0012] Optionally, in the above-mentioned battery module, the main body and the connecting part are riveted together; or, the main body and the connecting part are an integral structural component.

[0013] And / or, the end of the main body portion away from the connecting portion is engaged and limited with the inner side of the cover plate.

[0014] Optionally, the battery module further includes a first insulating member, which is at least partially located between the bottom surface of the connecting portion and the outer surface of the cover plate.

[0015] Optionally, in the above-mentioned battery module, the battery pad is provided with a first mounting hole;

[0016] The top surface of the connecting part is provided with a second mounting hole, which is a blind hole or a through hole and is provided with an internal thread;

[0017] The fastener includes a limiting end, an intermediate rod, and a connecting end connected sequentially along the axial direction. The limiting end is located outside the first mounting hole and is engaged with the plate for limiting. The intermediate rod passes through the first mounting hole, and the connecting end is located inside the second mounting hole and is threadedly connected to it.

[0018] Optionally, in the above battery module, the thickness of the connecting part is E, and the depth of the second mounting hole is H, where H and E satisfy 1mm≤H≤0.85E;

[0019] And / or, the thread outer diameter D of the connection end satisfies 5mm≤D≤10mm;

[0020] And / or, the axial thickness T of the limiting end satisfies 3mm≤T≤10mm.

[0021] Optionally, in the above-mentioned battery module, a conductive coating is provided between the top surface of the connecting portion and the plate.

[0022] Optionally, in the above-mentioned battery module, the conductive coating includes conductive adhesive.

[0023] Optionally, in the above-mentioned battery module, the conductive adhesive includes any one or more combinations of copper powder conductive adhesive and conductive silver adhesive.

[0024] Optionally, in the above-mentioned battery module, the temperature resistance of the conductive coating is greater than 100°C.

[0025] Optionally, in the above-mentioned battery module, the connecting part is provided with a third mounting hole that penetrates the top and bottom surfaces;

[0026] The top of the main body is located at the third mounting hole and is riveted thereto;

[0027] The tab and the conductive coating cover the top surface of the connector and the third mounting hole.

[0028] Optionally, in the above-mentioned battery module, in each of the battery cells, each of the connecting portions is connected to two or more of the fasteners;

[0029] Two or more of the fasteners are symmetrically arranged on both sides of the main body, that is, the projections of the two or more fasteners on the cover plate are symmetrically arranged with the projection of the main body on the cover plate as the center.

[0030] Optionally, in the above-mentioned battery module, the battery plate is an integral structural component.

[0031] As can be seen from the above technical solution, in the battery module provided by this application, the outer end of the electrode of each cell is fixedly connected to the electrode plate by fasteners, eliminating the need for welding. This avoids the adverse effects of the high temperature during the welding process on the cell, including the insulating components near the electrodes. For example, it effectively prevents the insulating components from softening, deforming, cracking, burning, or being damaged by the high temperature during the welding process, thereby ensuring the appearance quality and installation accuracy of the insulating components and their surrounding parts, and avoiding the risks of insulation failure and short circuits at this location. Attached Figure Description

[0032] 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 only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 An exploded view of a battery cell and a battery pad at the connection point, provided as an embodiment of this application.

[0034] Figure 2 This is a schematic diagram of the combined structure of multiple battery cells and wafers provided in an embodiment of this application.

[0035] Figure 3 A top view of a combined structure of a battery cell and a battery pack provided in an embodiment of this application.

[0036] Figure 4 for Figure 3 A sectional view of section AA in the middle.

[0037] Figure 5 for Figure 4 A magnified view of region B in the middle.

[0038] Figure 6 for Figure 5 A magnified view of region C in the middle.

[0039] Figure 7 for Figure 6 An enlarged structural diagram of the fasteners in the diagram.

[0040] in:

[0041] 1-Electrode, 2-Cover plate, 3-Conductive coating, 4-Bar plate, 5-Fastener

[0042] 6-First insulating component, 7-Second insulating component, 10-Battery cell,

[0043] 101 - Main body, 102 - Connecting part

[0044] 121 - Top surface, 122 - Bottom surface, 123 - Third mounting hole, 124 - Second mounting hole

[0045] 201-Cover body, 202-Positioning part, 211-First settling tank, 221-Second settling tank

[0046] 401-First mounting hole, 501-Limiting end, 502-Intermediate rod, 503-Connecting end. Detailed Implementation

[0047] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] Please see Figures 1 to 6This application provides a battery module comprising two or more battery cells 10, which are connected together by tabs 4. Specifically, each battery cell 10 includes a cover plate 2 and an electrode 1. The electrode 1 includes a main body 101 and a connecting part 102. The main body 101 is at least partially inserted into a through hole in the cover plate 2, with one end connected to an electrode tab located within the battery cell 10 and the other end connected to the connecting part 102. The connecting part 102 is engaged and positioned against the outer surface of the cover plate 2. The tabs 4 are located on the top surface 121 of the connecting part 102 and are fixedly connected to the top surface 121 by fasteners 5. In a specific implementation, a first insulating member 6 is also included, which is at least partially located between the bottom surface 122 of the connecting part 102 and the outer surface of the cover plate 2.

[0049] In some embodiments, the main body 101 and the connecting portion 102 are riveted together; alternatively, in other embodiments, the main body 101 and the connecting portion 102 may be an integral structural component. Furthermore, the end of the main body 101 furthest from the connecting portion 102 is engaged and limited with the inner surface of the cover plate 2. For an example of riveting the main body 101 and the connecting portion 102, please refer to [link to relevant documentation]. Figure 4 and Figure 5 The battery cell 10 includes a cover plate 2, an electrode 1, and a first insulating member 6. The electrode 1 includes a main body 101 and a connecting part 102. The main body 101 passes through a through hole in the cover plate 2. One end of the main body 101 is engaged and limited with the inner side of the cover plate 2, and the other end of the main body 101 is connected to the connecting part 102 and engaged and limited with the outer side of the cover plate 2 through the connecting part 102. The bottom surface 122 of the connecting part 102 is the side surface of the connecting part 102 closest to the cover plate 2. The first insulating member 6... At least partially located between the bottom surface 122 of the connecting portion 102 and the cover plate 2, the bottom surface 122 and the cover plate 2 are insulated from each other by the first insulating member 6; the top surface 121 of the connecting portion 102 is the side surface of the connecting portion 102 away from the cover plate 2, the tab 4 is located outside the top surface 121 of the connecting portion 102 and connected to it, and the tab 4 is fixedly connected to the top surface 121 of the connecting portion 102 by fasteners 5, so that the tab 4 is fixedly installed on the connecting portion 102 by fasteners 5. It should be noted that the connecting portion 102 located at the outer end of the electrode 1 in each cell 10 is fixedly connected to the tab 4 by fasteners 5, without welding. This avoids the high temperature of the welding process from adversely affecting the cell 10, including the first insulating member 6. For example, it can effectively prevent the first insulating member 6 from softening, deforming, cracking, burning or being damaged by the high temperature of the welding process, thereby ensuring the appearance quality and installation accuracy of the first insulating member 6 and its nearby components, and avoiding the risk of insulation failure and short circuit at this location.

[0050] Please see Figures 3 to 6In some embodiments, the tab 4 is provided with a first mounting hole 401; the top surface 121 of the connecting part 102 is provided with a second mounting hole 124, which is a blind hole or a through hole and is provided with an internal thread; one end of the fastener 5 is located outside the first mounting hole 401 of the tab 4 and is engaged and limited therewith, and the other end passes through the first mounting hole 401 and extends into the second mounting hole 124 of the connecting part 102 and is threadedly connected to the second mounting hole 124. Specifically, see Figure 6 and Figure 7 The fastener 5 includes a limiting end 501, an intermediate rod 502, and a connecting end 503 connected sequentially along the axial direction. The limiting end 501 is located outside the first mounting hole 401 of the bar plate 4 and is engaged with the outer surface of the bar plate 4 for limiting. The intermediate rod 502 passes through the first mounting hole 401 of the bar plate 4. The connecting end 503 is located inside the second mounting hole 124 of the connecting part 102 and is threadedly connected to it. In specific implementation, to ensure processing feasibility and meet connection strength requirements, the depth H of the second mounting hole 124 of the connecting part 102 can be any value within the range of 1mm to 0.85E, that is, H satisfies 1mm≤H≤0.85E, where E is the thickness of the connecting part 102 (if H is too small, the locking strength is not met; if H is too thick, the strength of the connecting part 102 itself will be affected); and / or, the thread outer diameter D of the connecting end 503 of the fastener 5 can be any value within the range of 5mm to 10mm, that is, D satisfies 5mm≤D≤10mm, and the internal thread of the second mounting hole 124 is adapted to it (if D is too small, the connection strength is insufficient; if D is too large, it will encroach on the width space of the connecting part 102, resulting in insufficient strength of the connecting part 102); and / or, the axial thickness T of the limiting end 501 of the fastener 5 can be any value within the range of 3mm to 10mm, that is, T satisfies 3mm≤T≤10mm (if T is too small, the connection strength is insufficient; if T is too large, it will encroach on the height space of the battery cell and the cost will be high).

[0051] In practice, the bar plate 4 can be assembled onto the connecting part 102 first, and then the fastener 5 with a screw structure (i.e., the connecting end 503 with a threaded structure) can be directly screwed into the threaded hole (i.e., the second mounting hole 124 mentioned above) of the connecting part 102 to fix the bar plate 4 onto the connecting part 102.

[0052] However, it is not limited to this. In other embodiments, fasteners with other structural forms can also be used to fix the plate 4 and the connecting part 102. For example, the top surface 121 of the connecting part 102 has a groove with only an L-shaped or T-shaped cross section. One end of the fastener 5 passes through the first mounting hole 401 of the plate 4, extends into the groove and engages with it, and the other end is located outside the plate 4 and is fixedly connected to the plate 4 by screws, adhesives, snap-fitting or other arbitrary means.

[0053] Furthermore, in some embodiments, to reduce the resistance between the pad 4 and the connecting portion 102, a conductive coating 3 is provided between the pad 4 and the top surface 121. Specifically, the conductive coating 3 can be made of conductive adhesive, such as copper powder conductive adhesive, conductive silver adhesive, or any combination thereof. Specifically, the conductivity of the conductive coating 3 is essentially the same as that of pure copper, which can increase the conductivity between the pad 4 and the connecting portion 102. Moreover, the conductive coating 3 has a certain temperature resistance, requiring that it will not experience performance degradation even when the battery cell reaches its maximum operating temperature. Generally, its temperature resistance is required to be greater than 100°C, meaning that the conductive coating 3 will not experience performance degradation when the temperature reaches 100°C.

[0054] Please see Figure 1 , Figure 4 and Figure 5 In some embodiments, the connecting portion 102 is provided with a third mounting hole 123 penetrating the top surface 121 and the bottom surface 122, and the top end of the main body portion 101 is located in the third mounting hole 123 and riveted to the limiting stepped surface in the third mounting hole 123; and as Figures 2 to 5 As shown, the electrode pad 4 and the conductive coating 3 both cover the top surface 121 of the connecting portion 102 and the third mounting hole 123, thereby encapsulating and protecting the top of the main body 101 and the connecting portion 102 in the connecting area. For example, it can prevent external moisture or impurities from entering the cell through the mounting gap at the top of the electrode 1, and it can also prevent the main body 101 and the connecting portion 102 of the electrode 1 and the nearby cover plate 2 from being damaged by bumps during the handling or use of the battery module.

[0055] Please see Figure 5 and Figure 6 In some embodiments, in the Z direction from the top surface 121 to the bottom surface 122 of the connecting portion 102, the third mounting hole 123 is a first stepped hole with a gradually decreasing diameter, and the circumferential side surface of the top end of the main body 101 is a first stepped side surface adapted to the first stepped hole, thereby achieving riveting between the top end of the main body 101 and the connecting portion 102; and / or, the first insulating member 6 includes an upward-opening box-shaped structure, the inner wall surface of which is a second stepped hole with a gradually decreasing diameter, the connecting portion 102 is located inside the box-shaped structure, and the circumferential side surface of the connecting portion 102 is adapted to the first stepped hole. The second stepped side of the second stepped hole is adapted to facilitate the installation of the connecting part 102 into the first insulating member 6; and / or, the outer side of the cover plate 2 is provided with a first recess 211 adapted to the bottom of the first insulating member 6, thereby facilitating the installation and positioning of the first insulating member 6 on the cover plate 2. Moreover, the inner side of the cover plate 2 is provided with a second recess 221 adapted to the end of the main body 101 located in the cell 10, thereby helping to reduce the utilization rate of the internal space of the cell and facilitating the installation and positioning of the main body 101 and the second insulating member 7 sleeved on its outer side in the cover plate 2.

[0056] Please see Figure 4 and Figure 5 In some embodiments, each connection portion 102 in each cell 10 is provided with a main body portion 101 and two or more fasteners 5. Furthermore, the two or more fasteners 5 are symmetrically arranged on both sides of the main body portion 101, that is, the projections of the two or more fasteners 5 on the cover plate 2 are symmetrically arranged with the projection of the main body portion 101 on the cover plate 2 as the center. Specifically, each connection portion 102 is provided with a third mounting hole 123 for mounting the main body portion 101 and two or more second mounting holes 124 for mounting the fasteners 5. The two or more second mounting holes 124 are symmetrically arranged on both sides of the third mounting hole 123. Therefore, by symmetrically arranging two or more fasteners 5, the connection between the main body portion 101 and the connection portion 102 is not affected, and the connection portion 102 is better suited for balanced force distribution.

[0057] Please see Figure 2 In the battery module provided in this application, the plate 4 used to connect multiple battery cells 10 is an integral structural component. However, it is not limited to this. In other embodiments, the plate 4 can also be an assembly composed of multiple connecting units combined by riveting, snap-fitting or other arbitrary methods to adapt to the actual needs of various products.

[0058] In some embodiments, the cover plate 2 may include a cover body 201 and a positioning part 202 located inside the cover body 201. In this case, the outer side of the cover body 201 is provided with a first recessed groove 211 adapted to the bottom of the first insulating member 6, and the inner side of the positioning part 202 is provided with a second recessed groove 221 adapted to the end of the main body 101 located inside the cell 10. In specific implementations, the cover body 201 and the positioning part 202 can be a separate structure. In this case, the cover body 201 serves as a top cover located outside the cell, and the positioning part 202 is an end cover structure located between the cover body 201 and the electrode group, which can provide insulation and positioning for the electrode group. Alternatively, in other embodiments, the cover body 201 and the positioning part 202 can be an integral structure. In this case, the cover body 201 is a metal plate (e.g., a plain aluminum plate), and the positioning part 202 is a plastic layer. The positioning part 202 is located on the inner side of the metal plate and is fixedly connected to it, which can provide insulation and positioning for the electrode group.

[0059] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed.

[0060] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0061] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery module comprising two or more battery cells, wherein the different battery cells are connected by a contact plate, characterized in that: The battery cell includes a cover plate and electrodes, and the electrodes include a main body and a connecting part; The main body is at least partially inserted through the through hole of the cover plate, with one end connected to the electrode tab of the electrode group located in the battery cell, and the other end connected to the connecting part; The connecting part is engaged and limited by the outer side of the cover plate; The plate is located on the top surface of the connecting part and is fixedly connected to the top surface by fasteners.

2. The battery module according to claim 1, characterized in that, The main body and the connecting part are riveted together; or, the main body and the connecting part are an integral structural component. And / or, the end of the main body portion away from the connecting portion is engaged and limited with the inner side of the cover plate.

3. The battery module according to claim 1, characterized in that, It also includes a first insulating element, which is at least partially located between the bottom surface of the connection and the outer surface of the cover plate.

4. The battery module according to claim 1, characterized in that, The bar is provided with a first mounting hole; The top surface of the connecting part is provided with a second mounting hole, which is a blind hole or a through hole and is provided with an internal thread; The fastener includes a limiting end, an intermediate rod, and a connecting end connected sequentially along the axial direction. The limiting end is located outside the first mounting hole and is engaged with the plate for limiting. The intermediate rod passes through the first mounting hole, and the connecting end is located inside the second mounting hole and is threadedly connected to it.

5. The battery module according to claim 4, characterized in that, The thickness of the connecting part is E, and the depth of the second mounting hole is H, where H and E satisfy 1mm≤H≤0.85E; And / or, the thread outer diameter D of the connection end satisfies 5mm≤D≤10mm; And / or, the axial thickness T of the limiting end satisfies 3mm≤T≤10mm.

6. The battery module according to claim 1, characterized in that, A conductive coating is provided between the top surface of the connecting part and the plate.

7. The battery module according to claim 6, characterized in that, The conductive coating includes a conductive adhesive; And / or, the temperature resistance of the conductive coating is greater than 100°C.

8. The battery module according to claim 6, characterized in that, The connecting part is provided with a third mounting hole that penetrates the top and bottom surfaces; The top of the main body is located inside the third mounting hole; The tab and the conductive coating cover the top surface of the connector and the third mounting hole.

9. The battery module according to claim 1, characterized in that, In each of the battery cells, each of the connecting portions is connected to two or more of the fasteners; The projections of two or more of the fasteners on the cover plate are arranged symmetrically with respect to the projection of the main body on the cover plate.

10. The battery module according to claim 1, characterized in that, The plate is a one-piece structural component.

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