Battery system and welding tool

Abstract

The utility model relates to the technical field of power batteries, and provides a battery system and a welding tool, the battery system comprises: a battery cell stack body, which is formed by stacking a plurality of battery cells in a layered manner, and two ends of each battery cell extend to form tabs; the support is provided with a total positive terminal and a total negative terminal, the total positive terminal is welded with the positive electrode of the battery cell stacking body, the total negative terminal is welded with the negative electrode of the battery cell stacking body, the tabs on the two sides of the battery cell located in the middle are welded with the tabs of the adjacent layers of battery cells respectively, and the support is provided with an avoiding part; the avoiding parts are used for exposing tabs on the same side of the battery cell stacking body; and the insulating cover plate is connected to the bracket, and the insulating cover plate is used for providing insulation for the tabs of the battery cell stacking body. Compared with the prior art, the battery system has the advantages that the bracket with the avoiding part is arranged in the battery system, and the total positive terminal and the total negative terminal are integrated on the bracket, so that the subsequent welding operation can be simplified while the quantity of materials of the battery system is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to power battery technology field, concretely is a kind of battery system and welding tool. BACKGROUND

[0002] With the rapid development of new energy industry, the market demand for low-cost, high-safety battery systems is increasing. Under the premise of not affecting the performance of the battery, optimizing the structural design, enhancing safety and reducing cost has become an industry trend.

[0003] Currently, in the power battery system, the electrical connection between the cell stack is usually achieved by busbar or tab welding process. Among them, an authorized Chinese utility model patent (authorized announcement number: CN 220368092U) introduces a busbar structure and cell module. The busbar structure described in the patent includes at least two layers of busbar layers, each layer is provided with a containing space for accommodating the cell pole, and at least one layer is equipped with tabs. These tabs are located in the containing space and in contact with the pole, thereby achieving stable electrical connection. Through this multi-layer design, the busbar not only ensures sufficient current-carrying capacity, but also avoids the problem of excessive thickness that may occur during single welding process, which helps to improve the welding quality and reduce welding defects.

[0004] After welding the busbar to the cell, they usually need to be connected to the bracket or terminal with total positive (+) and total negative (-). This is an important part of the electrical connection of the battery pack, ensuring that the current can be effectively collected from individual cells and transmitted to the external circuit. Although the use of busbar helps to improve welding quality and reduce defects, it also increases material cost. In contrast, in the traditional tab lapping scheme, in order to ensure stable connection between the tabs, a support frame is usually needed to fix their position. However, due to the complex internal structure of the power battery, after completing the welding of the adjacent cell tabs, this support frame is often difficult to remove, resulting in non-recyclable and thus increasing the manufacturing cost. SUMMARY

[0005] The utility model solves the technical problem in view of the present situation of prior art, and provides a kind of battery system and welding tool.

[0006] The technical scheme adopted by the utility model to solve the above technical problems is: a battery system is proposed, comprising: a cell stack formed by stacking a plurality of cells, each of the two ends of the cell extends out a tab;

[0007] The support is provided with a total positive terminal and a total negative terminal, the total positive terminal is welded with the positive electrode of the battery cell stack, the total negative terminal is welded with the negative electrode of the battery cell stack, the tab on the two sides of the battery cell in the middle is welded with the tab of the adjacent layer of battery cell respectively, the support is provided with a position avoiding part, and the position avoiding part is used for exposing the tabs on the same side of the battery cell stack.

[0008] The insulating cover plate is connected to the support, and is used for providing insulation for the tabs of the battery cell stack.

[0009] In the battery system, the support comprises:

[0010] A base;

[0011] An extension part is formed by extending from the two sides of the base to the direction away from the base, and is used for connecting the insulating cover plate.

[0012] In the battery system, the extension part is provided with a second limiting part and a clamping groove, the insulating cover plate is provided with a limiting groove and an elastic buckle, the second limiting part is abutted with the limiting groove, the limiting groove is used for providing limiting for the connection of the insulating cover plate and the extension part, and the elastic buckle is movably clamped with the clamping groove.

[0013] In the battery system, a plurality of reinforcing ribs are arranged on the side of the extension part facing the battery cell stack.

[0014] In the battery system, the side of the extension part away from the battery cell stack is provided with a second connecting part.

[0015] The utility model solves the above-mentioned technical problem and further proposes a welding tool for welding the above-mentioned battery system, which comprises a support plate and a pressing plate movably matched;

[0016] The welding tool comprises a supporting stroke and a resetting stroke, wherein,

[0017] When being in the supporting stroke, the position avoiding part is used for allowing the support plate to pass through, so that the support plate is moved to below the tab to be welded, and the pressing plate is pressed on the two tabs to be welded.

[0018] When being in the resetting stroke, the position avoiding part is used for resetting after allowing the support plate to pass through, and the pressing plate is away from the tab and resets.

[0019] In the welding tool, the support plate is provided with a first limiting portion, the first limiting portion is arranged perpendicularly to the extending direction of the tab and movably abuts against the end portion of the tab, and the first limiting portion is used for limiting the tab to be welded.

[0020] In the welding tool, the support plate is in L shape.

[0021] In the welding tool, the pressing plate comprises a pressing portion and a first connecting portion, and the pressing portion and the first connecting portion are connected in a staggered manner along the thickness direction of the pressing plate.

[0022] In the welding tool, a through groove is arranged on the pressing portion and penetrates the pressing portion.

[0023] Compared with the prior art, the welding tool has the following advantages:

[0024] (1) By arranging the bracket with the avoiding portion in the battery system and integrating the total positive terminal and the total negative terminal on the bracket, the subsequent welding operation can be simplified while the material quantity of the battery system is reduced.

[0025] (2) By arranging the movably matched support plate and the pressing plate, the welding operation of the adjacent layer tab of the battery cell stack can be realized.

[0026] (3) By arranging the first limiting portion on the support plate, the position of the battery cell can be adjusted by the position relationship between the tab and the first limiting portion during the tab welding process, until the tab end portion is abutted against the first limiting portion, so that the battery cell stack is more neat.

[0027] (4) By arranging the pressing plate in a staggered manner along the thickness direction, the contact area between the pressing plate and the tab is reduced, so as to ensure the appearance integrity outside the tab welding area as much as possible.

[0028] (5) By arranging the through groove on the pressing portion, the welding range of the tab is limited, so as to ensure the welding quality of the battery system.

[0029] (6) By arranging the second limiting portion and the clamping groove on the extending portion and arranging the limiting groove and the elastic buckle on the insulating cover plate, the precise installation of the insulating cover plate on the bracket is ensured.

[0030] (7) By arranging the plurality of spaced-apart reinforcing ribs on the extending portion, the insufficient strength of the bracket caused by the size reduction of the extending portion is compensated. By arranging the reinforcing ribs on the side facing the battery cell stack, the ribs can be shielded by the insulating cover plate after the insulating cover plate is installed on the bracket, so as to ensure the appearance of the entire battery system.

[0031] (8) By setting the connecting part on the extension of the support, the connection of the support and other components in the battery system is realized. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is a perspective view of the battery system of the utility model.

[0033] Figure 2 is Figure 1 the explosion view after adding the pressing plate and the support plate.

[0034] Figure 3 is the perspective view when the welding tool works.

[0035] Figure 4 is Figure 3 the perspective view after omitting the support in the battery system.

[0036] Figure 5 is Figure 3 the view in another direction.

[0037] Figure 6 is the perspective view of the pressing plate.

[0038] In the figure, 100, the cell stack; 110, the cell; 120, the tab; 200, the support; 210, the base; 220, the extension; 221, the second limiting part; 222, the clamping groove; 223, the reinforcing rib; 224, the second connecting part; 230, the avoiding part; 300, the insulating cover plate; 310, the limiting groove; 320, the elastic buckle; 400, the support plate; 410, the first limiting part; 500, the pressing plate; 510, the pressing part; 511, the through groove; 520, the first connecting part. DETAILED DESCRIPTION

[0039] The following is a specific embodiment of the utility model and in combination with the drawings, the technical scheme of the utility model is further described, but the utility model is not limited to these embodiments.

[0040] As described in the background, in the preparation process of the power battery, if it is necessary to weld the busbar on both sides of the cell with the tab, it will increase the additional components, and thus cause the cost of the power battery to rise. In the traditional tab lapping scheme, due to the complex internal structure of the power battery, the frame for supporting the cell tab is often difficult to take out after the welding is completed, and thus cannot be reused.

[0041] Referring to Figures 1 to 6 The battery system and the welding tool provided by the utility model can solve the above-mentioned problems, and the composition and working principle of the system will be introduced in detail.

[0042] A battery system comprises: an electric core stack 100, an insulating cover plate 300, and a bracket 200.

[0043] Specifically, the electric core stack 100 is formed by stacking a plurality of electric cores 110, and each electric core 110 has a tab 120 extending from both ends thereof; the bracket 200 is provided with a total positive terminal and a total negative terminal, the total positive terminal is welded to the positive electrode of the electric core stack 100, and the total negative terminal is welded to the negative electrode of the electric core stack 100; the tabs 120 on both sides of the electric core 110 in the middle are welded to the tabs 120 of the adjacent layer electric core 110; the bracket 200 is provided with a position avoiding part 230, which is used to expose the tabs 120 on the same side of the electric core stack 100; and the insulating cover plate 300 is connected to the bracket 200, and is used to provide insulation for the tabs 120 of the electric core stack 100.

[0044] Based on the above embodiment, an exemplary structure is provided (as shown in Figures 1 to 5 ), wherein one end of each electric core 110 extends a positive tab, and the other end extends a negative tab, and the positive and negative tabs 120 of the electric core 110 on the electric core stack 100 are arranged in a cross manner.

[0045] For example, in Figure 1 , the lowermost electric core 110 has a negative tab 120 on the left side and a positive tab 120 on the right side; the second layer electric core 110 is opposite to the lowermost electric core 110, and has a positive tab 120 on the left side and a negative tab 120 on the right side; the third layer electric core 110 has a positive tab 120 on the left side and a negative tab 120 on the right side, which is the same as the lowermost electric core 110, and so on.

[0046] Of course, in Figure 1 , the lowermost electric core 110 can also have a positive tab 120 on the left side and a negative tab 120 on the right side; at this time, the second layer electric core 110 is opposite to the lowermost electric core 110, and has a negative tab 120 on the left side and a positive tab 120 on the right side; the third layer electric core 110 has a positive tab 120 on the left side and a negative tab 120 on the right side, which is the same as the lowermost electric core 110, and so on.

[0047] When a single electric core stack 100 is used, referring to Figure 2 , the tabs 120 on the right side of the electric core stack 100 are sequentially connected, i.e., the tab 120 of the lowermost layer is connected to the tab 120 of the second layer, the tab 120 of the third layer is connected to the tab 120 of the fourth layer, and so on. On the other side (e.g., the left side in Figure 2 ), the tab 120 of the lowermost electric core 110 and the tab 120 of the uppermost electric core 110 are connected to the total positive terminal and the total negative terminal on the bracket 200, respectively.

[0048] When a battery system consists of two cell stacks 100 connected in series and parallel, the corresponding positive terminals of the two cell stacks 100 should first be connected to each other (if in series) and the corresponding negative terminals to each other, or their positive and negative terminals should be connected in parallel (if in parallel). Next, the electrical connection of the entire system is completed by connecting the positive terminal of one cell stack 100 to the main positive terminal on the support 200 and connecting the negative terminal of the other cell stack 100 to the main negative terminal on the support 200.

[0049] When connecting the tab 120 on the side of the cell stack 100 with the support 200, the support 200 is provided with a clearance part 230, which provides sufficient space for welding the tab 120 inside the complex battery system, ensuring the convenience and quality of the welding operation.

[0050] This solution enables the welding of the aforementioned battery system. The proposed welding fixture includes a movable support plate 400 and a pressure plate 500.

[0051] The welding fixture includes a support stroke and a reset stroke, wherein,

[0052] When in the support stroke, the clearance part 230 is used for the support plate 400 to pass through, so that it moves to below the electrode tab 120 to be welded, to provide support for the electrode tab 120 to be welded, and the pressure plate 500 presses on the two electrode tabs 120 to be welded.

[0053] When in the reset stroke, the clearance part 230 is used to allow the support plate 400 to pass through and reset, and the pressure plate 500 moves away from the tab 120 and resets.

[0054] The movable cooperation between the support plate 400 and the pressure plate 500 can be achieved by other power devices, such as a combination of power components such as a robotic arm, special equipment, or cylinders and motors.

[0055] During the actual assembly process, refer to Figure 2 First, the bracket 200 is installed in the battery system, and then the bottom cell 110 is positioned using the pressure plate 500. Figure 2 The left-side tab 120 is pressed against the main positive or main negative terminal on the bracket 200 for soldering. Next, the second and third layers of cells 110 are stacked sequentially, and the tabs 120 of these two layers of cells 110 are soldered. After the tabs 120 of the second and third layers of cells 110 are soldered, the fourth and fifth layers of cells 110 are stacked, and the tabs 120 of these two layers of cells 110 are soldered, and so on. When it is necessary to solder the tabs 120 of two adjacent layers of cells 110, the support plate 400 will move to be below the tabs 120 of these two layers of cells 110.

[0056] Due to the design of the avoiding part 230 on the support frame 200, space is provided for the movement of the support plate 400 in the complex structure of the battery system. After the support plate 400 passes through the avoiding area, it moves to the lower side of the two layers of the cell 110 tab 120 to be welded, and the pressing plate 500 moves to the upper side of the two layers of the cell 110 tab 120, for example, by heating the tab material to rapidly melt and then cool and solidify to form a welding point, thereby completing the welding of the two layers of the cell 110 tab 120. Through the support plate 400 and the pressing plate 500, the welding operation of the two layers of the cell 110 tab 120 is completed. After welding is completed, the support plate 400 is reset by passing through the avoiding area again, and the pressing plate 500 is also reset accordingly, so as to prepare for subsequent welding operations.

[0057] When welding the battery system with different sizes of the cell 110 but the same size of the tab 120, the pressing plate 500 and the support plate 400 can be reused, thereby making the welding tool of the utility model have better compatibility.

[0058] It is worth noting that in other embodiments of the utility model, the support plate 400 is provided with a first limiting part 410, which is arranged perpendicularly to the extension direction of the tab 120 and movably abuts against the end of the tab 120, for providing limiting for the tab 120 to be welded.

[0059] When the support plate 400 moves to the lower side of the position to be welded, and the end of the tab 120 is not aligned with the first limiting part 410, the cell 110 in the stack can be manually adjusted until the tab 120 is aligned with the first limiting part 410. The first limiting part 410 is designed to ensure the welding quality of the battery system.

[0060] Referring to Figure 2 With Figure 4 , the support plate 400 is preferably designed as an L-shaped, wherein the first limiting part 410 is vertically arranged.

[0061] Referring to Figure 2 , the pressing plate 500 comprises a pressing part 510 and a first connecting part 520, which are connected in a staggered manner along the thickness direction of the pressing plate 500.

[0062] The pressing part 510 is used for pressing on the tab 120 to be welded, and the first connecting part 520 is used for connecting an external power mechanism, so as to realize the movement of the pressing plate 500. The pressing part 510 and the first connecting part 520 are connected in a staggered manner along the thickness direction of the pressing plate 500, which aims to reduce the contact area between the pressing plate 500 and the tab 120, so as to ensure the appearance integrity of the tab 120 as much as possible.

[0063] Referring to Figure 4The pressing part 510 is provided with a through slot 511 for limiting the welding range of the tab 120 to ensure the welding quality of the battery system.

[0064] With reference to Figure 2 The bracket 200 comprises a base 210 and an extension part 220 extending from both sides of the base 210 away from the base 210 for connecting the insulating cover plate 300.

[0065] In one embodiment, the base 210 and the extension part 220 are integrally formed by injection molding. The base 210 serves as the support structure of the entire bracket 200, while the extension part 220 is used to connect the insulating cover plate 300 to provide protection for the tab 120 after the welding is completed.

[0066] With reference to Figure 2 With Figure 3 The extension part 220 is provided with a second limiting part 221 and a clamping groove 222, and the insulating cover plate 300 is provided with a limiting groove 310 and an elastic buckle 320. The abutting of the second limiting part 221 and the limiting groove 310 provides limiting for the connection of the insulating cover plate 300 and the extension part 220, and the elastic buckle 320 and the clamping groove 222 are movably connected.

[0067] After the welding of the tab 120 on the battery cell stack 100 is completed and the pressing plate 500 and the support plate 400 are reset, first, the limiting groove 310 on the insulating cover plate 300 is aligned with the second limiting part 221 on the extension part 220 to determine the installation position of the insulating cover plate 300. After the insulating cover plate 300 is positioned, the elastic buckle 320 is pushed to be connected with the clamping groove 222 on the extension part 220, thereby completing the installation of the insulating cover plate 300. The design of the second limiting part 221 and the limiting groove 310 is to ensure the accurate installation between the insulating cover plate 300 and the bracket 200, and the design of the elastic buckle 320 and the clamping groove 222 is to realize the fixation of the two. Preferably, the elastic buckle 320 and the insulating cover plate 300 are integrally formed by injection molding.

[0068] With reference to Figure 5 The side of the extension part 220 facing the battery cell stack 100 is provided with a plurality of reinforcing ribs 223, and the plurality of reinforcing ribs 223 are arranged at intervals on the side of the extension part 220 facing the battery cell stack 100.

[0069] In the process that the support plate 400 moves to support the tab 120 of the battery cell 110, in order to avoid the interference between the support plate 400 and the support frame 200, the width of the avoiding part 230 on the support frame 200 needs to be large enough. Correspondingly, in order to ensure that the width of the avoiding part 230 is large enough, the width of the extension part 220 must be appropriately reduced, but this may reduce the structural strength of the support frame 200. In order to solve the above problems, in an embodiment of the utility model, a plurality of reinforcing ribs 223 arranged at intervals are arranged on the extension part 220, so as to make up for the problem of insufficient strength of the support frame 200 caused by the size reduction of the extension part 220. The reinforcing ribs 223 are arranged on the side facing the battery cell stack 100, so that after the insulating cover plate 300 is installed on the support frame 200, the ribs are shielded by the insulating cover plate 300, thereby ensuring the aesthetic appearance of the whole battery system.

[0070] Referring to Figure 3 , the side of the extension part 220 away from the battery cell stack 100 is provided with a second connecting part 224, which is used to realize the connection between the support frame 200 and other components in the battery system. Preferably, the second connecting part 224 is in a block structure and is integrally formed with the support frame 200, and a round corner is arranged on the outer side thereof. A threaded hole can be arranged at the middle position of the second connecting part 224, so as to realize the threaded connection with other components. In another embodiment, the middle position of the second connecting part 224 is designed as a through hole, so as to adapt to different connection requirements of the support frame 200.

[0071] The working principle of the scheme is as follows: referring to Figure 2 , first, the support frame 200 is installed in the battery system, then the lowermost battery cell 110 Figure 2 is pressed on the total positive terminal or total negative terminal on the support frame 200 by the pressing plate 500 for welding. Next, the support plate 400 and the pressing plate 50 are sequentially stacked with the second layer and the third layer of battery cells 110 by a mechanical hand, a special device or a combination of a cylinder and a motor power assembly, and the tabs 120 of the two layers of battery cells 110 are welded. After the welding of the tabs 120 of the second layer and the third layer of battery cells 110 is completed, the fourth layer and the fifth layer of battery cells 110 are continuously stacked, and the tabs 120 of the two layers of battery cells 110 are welded, and so on. When the tabs 120 of two adjacent battery cells 110 need to be welded, the support plate 400 will move to the lower side of the tabs 120 of the two layers of battery cells 110.

[0072] It should be noted that all the directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the utility model are only used to explain the relative positional relationship, movement condition and the like between the components in a certain specific posture, and if the specific posture changes, the directional indications will also change accordingly.

[0073] In addition, the descriptions such as "first", "second", "one", etc. in the present application are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0074] In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixing" and the like should be broadly understood, for example, "fixing" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through intermediate medium; can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0075] In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

[0076] The specific embodiments described herein are merely illustrative of the present application. Those skilled in the art of the present application can make various modifications or supplements to the described specific embodiments or replace them with similar ways, but will not deviate from the scope defined by the spirit of the present application.

Claims

1. A battery system characterized by, The application relates to a welding tool for welding the tab of a battery cell. The welding tool comprises: a battery cell stack formed by a plurality of battery cells stacked in layers, both ends of each battery cell extending out of a tab; a support frame provided with a total positive terminal and a total negative terminal, the total positive terminal being welded with the positive electrode of the battery cell stack, the total negative terminal being welded with the negative electrode of the battery cell stack, the tabs on both sides of the battery cell in the middle being welded with the tabs of the battery cell in the adjacent layer, the support frame being provided with a position-avoiding part for exposing the tabs on the same side of the battery cell stack to the outside; 2. The battery system of claim 1, wherein, an insulating cover plate connected to the support frame, the insulating cover plate being used for providing insulation for the tabs of the battery cell stack. The support frame comprises: a base; 3. A battery system as claimed in claim 2, wherein, an extension part extending from both sides of the base in a direction away from the base, used for connecting the insulating cover plate.

4. The battery system of claim 2, wherein, The extension part is provided with a second limiting part and a clamping groove, the insulating cover plate is provided with a limiting groove and an elastic buckle, the second limiting part is in abutment with the limiting groove, used for providing limiting for the connection of the insulating cover plate and the extension part, and the elastic buckle is in movable clamping connection with the clamping groove.

5. The battery system of claim 2, wherein, The extension part is provided with a plurality of reinforcing ribs on the side facing the battery cell stack, and the reinforcing ribs are arranged at intervals on the side of the extension part facing the battery cell stack.

6. A welding jig for welding the battery system as claimed in any one of claims 1 to 5, characterized by The side of the extension part away from the battery cell stack is provided with a second connecting part. The welding tool comprises a movable supporting plate and a pressing plate; The welding tool comprises a supporting stroke and a resetting stroke, wherein, when in the supporting stroke, the position-avoiding part is used for allowing the supporting plate to pass through and move to below the tabs needing to be welded, for providing support for the tabs needing to be welded, and the pressing plate is pressed on the two tabs needing to be welded; 7. A welding fixture as claimed in claim 6, wherein when in the resetting stroke, the position-avoiding part is used for allowing the supporting plate to pass through and reset, and the pressing plate is away from the tabs and resets.

8. A welding fixture as defined in claim 6, wherein, The supporting plate is provided with a first limiting part, the first limiting part is arranged perpendicularly to the extending direction of the tab and is in movable abutment with the end of the tab, and is used for providing limiting for the tab needing to be welded.

9. A welding fixture as defined in claim 6, wherein, The supporting plate is in L shape.

10. A welding fixture as claimed in claim 9, wherein, The pressing plate comprises a pressing part and a first connecting part, and the pressing part and the first connecting part are connected in a staggered manner along the thickness direction of the pressing plate. The pressing part is provided with a through groove penetrating through the pressing part.

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