Multi-layer laminated cell battery

Abstract

A multi-layer laminated cell battery, comprising: a laminated cell assembly, a positive electrode cover plate, and a negative electrode cover plate, wherein the laminated cell assembly comprises a plurality of layers of laminated cells, tabs are connected to both ends of each laminated cell, and the tabs at different layers are misaligned with each other; the positive electrode cover plate and the negative electrode cover plate are respectively mounted at both ends of the laminated cells; a busbar connecting piece in contact with tabs is mounted on the surface of each of the positive electrode cover plate and the negative electrode cover plate. By mounting tabs and busbar connecting pieces at both ends of a plurality of layers of laminated cells and connecting a plurality of tabs to the busbar connecting piece on the same side, the discharge requirements of the plurality of layers of laminated cells are satisfied. The tabs comprise current guide pieces of different lengths, so as to adapt to the conductivity requirements of laminated cells at different heights; and when the lengths of tab connecting pieces of the laminated cells are insufficient to satisfy the assembly requirements, the current guide pieces are added onto the tab connecting pieces so as to satisfy the assembly requirements.

Description

A multi-layer core-stacked battery TECHNICAL FIELD

[0001] The utility model belongs to new energy battery technical field, especially relate to a multi-layer core-stacked battery. BACKGROUND

[0002] The high energy density, no memory effect, long single cycle period, high efficiency, clean and pollution-free characteristics of lithium battery make it widely used. The energy storage industry and the power battery industry have a surge in demand for high capacity, high rate charge and discharge of batteries. However, there are many challenges in the process of thickening the battery, such as how to assemble very thick pole pieces together, and the increase of process scrap rate caused by long tab.

[0003] UTILITY MODEL CONTENT

[0004] In order to solve at least one problem in the background art, the utility model provides a multi-layer core-stacked battery.

[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme:

[0006] A multi-layer core-stacked battery, comprising: a core-stacked assembly, a positive cover plate and a negative cover plate;

[0007] The core-stacked assembly comprises a plurality of layers of stacked core, and each of the core is connected with a tab at both ends, and the tabs of different layers are offset from each other;

[0008] The positive cover plate and the negative cover plate are respectively installed at both ends of the core;

[0009] The positive cover plate and the negative cover plate are respectively installed at both ends of the core;

[0010] Preferably, the core-stacked assembly comprises a first core, a second core and a third core;

[0011] The second core is stacked on the surface of the third core;

[0012] The first core is stacked on the surface of the second core.

[0013] Preferably, the first core is connected with a first tab at both ends;

[0014] The second core is connected with a second tab at both ends;

[0015] The third core is connected with a third tab at both ends.

[0016] Preferably, the first tab, the second tab and the third tab are arranged offset from each other, and are connected to the busbar.

[0017] Preferably, the second tab is located in the middle of the busbar;

[0018] The first tab is located on one side of the second tab;

[0019] The third tab is located on the other side of the second tab.

[0020] Preferably, the first tab, the second tab and the third tab each comprise a flow guide fin arranged in a vertical direction and a tab connecting piece arranged in a horizontal direction;

[0021] The flow guide fin and the tab connecting piece are fixedly connected.

[0022] Preferably, the length of the flow guide fin is proportional to the horizontal height of the first tab, the second tab and the third tab.

[0023] Preferably, the tab and the bus connecting piece are welded.

[0024] Preferably, the positive cover plate and the negative cover plate are connected with the bus connecting piece by welding or riveting.

[0025] Preferably, the shape of the bus connecting piece comprises a rectangle, an "L" shape, a trapezoid and an "X" shape.

[0026] The beneficial effects of the present application are as follows:

[0027] 1. The present application connects multiple tabs with a bus connecting piece on one side by installing tabs and bus connecting pieces at both ends of the multi-layer core, thereby achieving the discharge requirement of the multi-layer core.

[0028] 2. The tabs of the present application comprise flow guide fins of different lengths to meet the conductive requirements of cores of different heights. When the length of the tab connecting piece of the core is insufficient to meet the assembly requirement, a flow guide fin is added to the tab connecting piece, thereby meeting the assembly requirement.

[0029] Other features and advantages of the present application will be described in the following description, and some will become apparent from the description, or will be understood from the practice of the present application. The purpose and other advantages of the present application can be achieved and obtained by the structure indicated in the description and the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0031] Figure 1 shows a structure diagram of a multi-layer core battery of the utility model;

[0032] Figure 2 shows a structure diagram of the first tab of the utility model;

[0033] Figure 3 shows a structure diagram of the heat conduction channel of the utility model.

[0034] In the drawing: 1, first core; 101, first tab; 2, second core; 201, second tab; 3, third core; 301, third tab; 4, positive cover plate; 5, negative cover plate; 6, busbar; 7, heat conduction channel. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely explained below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.

[0036] A multi-layer core battery comprises a core assembly, a positive cover plate 4 and a negative cover plate 5. The core assembly comprises a plurality of layers of stacked cores, and each core is connected with a tab at both ends, and the tabs of different layers are offset from each other. The positive cover plate 4 and the negative cover plate 5 are respectively installed at both ends of the core; and the positive cover plate 4 and the negative cover plate 5 are both installed with a busbar 6 in contact with the tab.

[0037] It should be noted that in the present embodiment, in order to meet the condition that the thickness of the core is very thick and the length of the tab of the core is insufficient to meet the assembly requirement, a flow guide piece is added to the tab to indirectly realize the assembly requirement, which will be specifically explained below in combination with Figures 1 and 2.

[0038] As shown in Figure 1, the core assembly comprises a first core 1, a second core 2 and a third core 3. The second core 2 is stacked on the surface of the third core 3, and the first core 1 is stacked on the surface of the second core 2. Moreover, the first core 1 is connected with a first tab 101 at both ends, the second core 2 is connected with a second tab 201 at both ends, and the third core 3 is connected with a third tab 301 at both ends. Meanwhile, the first tab 101, the second tab 201 and the third tab 301 are arranged offset from each other and are all connected to the busbar 6.

[0039] It should be noted that when the number of stacked cores is large, if it is greater than 3 layers, the tabs on the stacked cores can be arranged at different positions, such as tabs in the middle of the stacked cores, tabs left offset of the stacked cores, and tabs right offset of the stacked cores. In FIG. 1, the second tab 201 is located in the middle of the bus connecting sheet 6, the first tab 101 is located on one side of the second tab 201, and the third tab 301 is located on the other side of the second tab 201. The advantage of this is to make full use of the limited space and avoid the problem of large bending space required after the tab connecting sheet is bent on the same vertical line.

[0040] Further, as shown in FIGS. 1 and 2, the first tab 101, the second tab 201, and the third tab 301 each include a flow guide sheet (A in FIG. 2) arranged in the vertical direction and a tab connecting sheet (B in FIG. 2) arranged in the horizontal direction, and the flow guide sheet and the tab connecting sheet are fixedly connected. In addition, the length of the flow guide sheet is directly proportional to the horizontal height of the first tab 101, the second tab 201, and the third tab 301.

[0041] It should be noted that the length of the flow guide sheet is related to the thickness of the multiple stacked cores. In FIG. 1, the first stacked core 1 is located at the highest layer, and the length of the flow guide sheet thereof is the longest. The third stacked core 3 is located at the bottom layer, and the length of the flow guide sheet thereof is the shortest.

[0042] Further, the tabs are welded with the bus connecting sheet 6, and the welding can be laser welding or ultrasonic welding, etc. In addition, the positive cover plate 4 and the negative cover plate 5 are connected with the bus connecting sheet 6 by welding or riveting, and are fixed on the cover plate by laser welding or riveting, etc.

[0043] Further, the shape of the bus connecting sheet 6 includes a strip shape, an "L" shape, a trapezoidal shape, and an "X" shape.

[0044] It should be noted that the shape of the flow guide sheet can be rectangular. When the width of the battery core is wide and the number of offset stacked cores is large, an "L" shaped flow guide sheet design can be used to extend to the specified cover plate welding area range in the middle. The trapezoidal shape, the "X" shape, and other design shapes are provided with a weak connecting sheet flow area, which can suddenly pass a large current and ensure that the weak area can be preferentially fused, thereby protecting the battery core. One of the functions of the horizontally arranged heat dissipation flow connecting sheet (bus connecting sheet 6 in FIG. 1) is to connect the flow guide sheets of each stacked core to form a main flow channel, and the large surface area also has a certain heat dissipation effect.

[0045] As shown in FIG. 3, a structure for improving heat dissipation is provided, in which the positive cover plate 4 and the negative cover plate 5 are provided with a heat conduction channel 7 at the bottom surface, and the heat conduction channel 7 is located directly below the bus connecting sheet 6. When the airflow passes through, it can carry away the heat accumulated in the heat conduction channel 7, thereby achieving a certain heat dissipation effect on the bus connecting sheet 6.

[0046] The multi-layer core battery of FIG. 1 can be installed in various ways, which are described below.

[0047] Installation method one

[0048] At the tab tabbing stage, the tab tabs at different positions are cut according to the designed positions, including right-biased, left-biased and centered tab tabs, which are respectively stacked by heat compounding or Z-stacking, etc. The heat compounding adopts a double-separator stacking method, and the Z-stacking adopts a single-separator stacking method. The stacked tab tabs are folded in the thickness direction with a downward bias. The distance between the folding position and the center of the single core is between 1 / 3h and 1 / 2h of the thickness h of the single core, and then ultrasonic pre-welding is performed. The pre-welding function is to fix the tab tab morphology, and the area is relatively small, which can be half of 2*tab tab width.

[0049] The excess tab tabs are cut, and then the ultrasonic welded tab tabs are ultrasonic welded with the corresponding flow guide tabs. The welding area is calculated according to the capacity and current-carrying rate of the battery, and can be selected as 5*(tab tab width-5). The cores in these states are stacked in order from the centered tab tab to the biased tab tab, as shown in FIG. 1. The stacking order is the core with the centered tab tab at the bottom, the core with the right-biased tab tab at the second layer, and the core with the left-biased tab tab at the third layer. Then the welded flow guide tabs are folded together according to the appropriate angle and method. The folding position is generally biased downward in the thickness direction of the core, which prepares for the subsequent welding of the cover plate. Then the flow guide tabs are also combined together by welding, generally by toothless ultrasonic welding, which prepares for the subsequent laser welding of the cover plate on the welding surface.

[0050] The other pole is welded in the same way, and then the core is put into the shell. The key position is positioned by a tool, and then the positive cover plate 4 and the negative cover plate 5 are welded with the flow guide tabs. Generally, laser welding is used because of its high welding efficiency and high welding strength. After the welding of the cover plate and the flow guide tabs is completed, the flow guide tabs, tab tabs, etc. are bent to the position of the shell assembly state. Finally, the shell and the cover plate are welded.

[0051] Installation method two

[0052] Prepare the same tab tab biased or centered core, and then fold the tab tabs on the core and pre-weld. The folding position is generally biased by a distance in the thickness direction of the core, or even completely biased to one side. After pre-welding, the excess part is cut according to the different lengths of the tab tabs, etc. Then the two cores are placed head to head on the positive cover plate 4 or the negative cover plate 5.

[0053] The laser welding is performed, the other pole is also first folded to gather the tab connecting piece, the tab connecting piece ultrasonic pre-welding is performed, the tab connecting piece of the excess part is cut, the corresponding length of the flow guide piece ultrasonic welding is performed again on the pre-welding mark, and the flow guide piece and the folded tab connecting piece can be directly pre-welded once, so that the process is reduced, but the operation is slightly more difficult.

[0054] Subsequently, the core is folded and glued, then the flow guide piece is ultrasonically welded at the appropriate position, then the core is inserted into the shell, the positive or negative cover plate and the flow guide piece are welded, the welding position is above the flow guide piece ultrasonic welding mark, then the cover plate, the flow guide piece and the tab connecting piece are bent to the appropriate position until they are assembled on the shell, and finally the shell and the cover plate are welded.

[0055] Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced equivalently, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. A multi-layered core battery, characterized by, include: Stacked core assembly, positive electrode cover plate (4) and negative electrode cover plate (5); The stacked core assembly includes several stacked cores, and each stacked core has tabs connected to both ends, with the tabs of different layers being offset from each other. The positive electrode cover plate (4) and the negative electrode cover plate (5) are respectively installed at both ends of the stacked core; Both the positive electrode cover plate (4) and the negative electrode cover plate (5) are equipped with a busbar connector (6) that contacts the electrode tab.

2. The multi-layered core battery of claim 1, wherein, The stacked core assembly includes a first stacked core (1), a second stacked core (2), and a third stacked core (3); The second core (2) is stacked on the surface of the third core (3); The first core stack (1) is stacked on the surface of the second core stack (2).

3. The multi-layered core battery of claim 2, wherein, The first stacked core (1) has first pole tabs (101) connected to both ends; The second stacked core (2) has second pole tabs (201) connected to both ends; The third stack core (3) is connected to a third pole piece (301) at both ends.

4. The multi-layered core battery of claim 3, wherein, The first electrode (101), the second electrode (201) and the third electrode (301) are offset from each other and are all connected to the bus connector (6).

5. The multi-stack core battery of claim 3, wherein, The second electrode (201) is located in the middle of the bus connector (6); The first electrode tab (101) is located on one side of the second electrode tab (201); The third electrode (301) is located on the other side of the second electrode (201).

6. The multi-stack core battery of claim 3, wherein, The first electrode (101), the second electrode (201) and the third electrode (301) each include a guide plate arranged in the vertical direction and an electrode connecting plate arranged in the horizontal direction; The guide plate and the electrode connecting plate are fixedly connected.

7. A multi-stack core battery as claimed in claim 6, wherein, The length of the guide plate is proportional to the horizontal height of the first tab (101), the second tab (201), and the third tab (301).

8. The multi-stack core battery of claim 1, wherein, The electrode tab is welded to the busbar connector (6).

9. The multi-stack core battery of claim 1, wherein, Both the positive electrode cover plate (4) and the negative electrode cover plate (5) are connected to the busbar connector (6) by welding or riveting.

10. A multi-stacked core battery as claimed in any one of claims 1 to 9, wherein, The shape of the bus connector (6) includes rectangular, "L" shaped, trapezoidal and "X" shaped.

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