Multi-layer laminated core battery

Abstract

The utility model belongs to the technical field of new energy batteries, and provides a multi-layer laminated core battery which comprises a laminated core assembly, a positive electrode cover plate and a negative electrode cover plate, the laminated core assembly comprises a plurality of layers of laminated cores, the two ends of each laminated core are connected with tabs, and the tabs of different layers are mutually biased; the positive electrode cover plate and the negative electrode cover plate are respectively arranged at two ends of the laminated core; and the surfaces of the positive electrode cover plate and the negative electrode cover plate are respectively provided with a confluence connecting sheet which is in contact with the tabs. According to the utility model, the tabs and the confluence connecting sheets are arranged at the two ends of the multi-layer laminated core, and the plurality of tabs are connected with the confluence connecting sheet at one side, so that the discharge requirement of the multi-layer laminated core is realized; the pole lug comprises the flow deflectors with different lengths so as to meet the conductive requirements of the laminated cores with different heights, and when the length of the pole lug connecting piece of the laminated core is not enough to meet the assembly requirements, the assembly requirements are further met by adding a section of flow deflector on the pole lug connecting piece.

Description

Technical Field

[0001] The utility model belongs to the technical field of new energy batteries, and particularly relates to a multi-layer stacked core battery. Background Art

[0002] Lithium batteries are widely used due to their high energy density, no memory effect, long single-cell cycle, high efficiency, cleanliness and pollution-free. The energy storage industry and the power battery industry have a surge in demand for high-capacity batteries and high-rate charge and discharge. However, there are many challenges in the process of making batteries thicker, such as how to put very thick pole pieces together, and the increase in process scrap rate caused by the lengthening of the pole ears. Utility Model Content

[0003] In order to solve at least one problem in the background technology, the utility model provides a multi-layer stacked battery.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A multi-layer stacked core battery, comprising: a stacked core assembly, a positive electrode cover plate and a negative electrode cover plate;

[0006] The stacked core assembly comprises a plurality of stacked cores, both ends of each of the stacked cores are connected with tabs, and the tabs of different layers are offset from each other;

[0007] The positive electrode cover plate and the negative electrode cover plate are respectively installed at two ends of the stacked core;

[0008] The surfaces of the positive electrode cover plate and the negative electrode cover plate are both provided with busbars in contact with the pole tabs.

[0009] Preferably, the stacked core assembly comprises a first stacked core, a second stacked core and a third stacked core;

[0010] The second core stack is stacked on the surface of the third core stack;

[0011] The first core stack is stacked on the surface of the second core stack.

[0012] Preferably, two ends of the first stacked core are connected with first pole ears;

[0013] The second stacked core has second tabs connected to both ends;

[0014] The third pole tabs are connected at both ends of the third stacked core.

[0015] Preferably, the first pole lug, the second pole lug and the third pole lug are arranged offset from each other and are all connected to the busbar.

[0016] Preferably, the second pole lug is located in the middle of the busbar;

[0017] The first pole lug is located on one side of the second pole lug;

[0018] The third pole tab is located on the other side of the second pole tab.

[0019] Preferably, the first pole lug, the second pole lug and the third pole lug each include a guide plate arranged in a vertical direction and a pole lug connecting plate arranged in a horizontal direction;

[0020] The guide plate and the pole lug connecting plate are fixedly connected.

[0021] Preferably, the length of the guide plate is proportional to the horizontal heights of the first pole lug, the second pole lug and the third pole lug.

[0022] Preferably, the pole tabs are welded to the busbars.

[0023] Preferably, the positive electrode cover plate and the negative electrode cover plate are connected to the busbar by welding or riveting.

[0024] Preferably, the shapes of the busbars include rectangular, “L”-shaped, trapezoidal and “X”-shaped.

[0025] Beneficial effects of the utility model:

[0026] 1. The utility model realizes the discharge requirement of the multi-layer stacked core by installing pole ears and bus connection pieces at both ends of the multi-layer stacked core and connecting multiple pole ears with the bus connection piece on one side.

[0027] 2. The pole tabs of the utility model include guide plates of different lengths to meet the conductivity requirements of stacked cores of different heights. When the length of the pole tab connecting plate of the stacked core is not enough to meet the assembly requirements, the assembly requirements can be met by adding a guide plate to the pole tab connecting plate.

[0028] Other features and advantages of the utility model will be described in the following description, and partly become apparent from the description, or understood by implementing the utility model. The purpose and other advantages of the utility model can be realized and obtained by the structures indicated in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A schematic structural diagram of a multi-layer stacked core battery of the utility model is shown;

[0031] Figure 2 The schematic diagram of the structure of the first pole ear of the utility model is shown;

[0032] Figure 3 The schematic diagram of the structure of the heat conduction channel of the utility model is shown.

[0033] In the figure: 1, first stacked core; 101, first pole ear; 2, second stacked core; 201, second pole ear; 3, third stacked core; 301, third pole ear; 4, positive electrode cover plate; 5, negative electrode cover plate; 6, busbar connecting piece; 7, heat conduction channel. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0035] A multi-layer stacked core battery comprises a stacked core assembly, a positive electrode cover plate 4 and a negative electrode cover plate 5. The stacked core assembly comprises a plurality of stacked cores, both ends of each stacked core are connected with pole tabs, and pole tabs of different layers are 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; the surfaces of the positive electrode cover plate 4 and the negative electrode cover plate 5 are both installed with busbars 6 in contact with the pole tabs.

[0036] It should be noted that in this embodiment, in order to meet the requirements of the thickness of the stacked core battery, when the length of the stacked core tab is not enough to meet the assembly requirements, a guide plate is added to the tab to meet the assembly requirements in disguise. Figure 1 and 2 Provide a specific description of it.

[0037] like Figure 1 As shown, the stacked core assembly includes a first stacked core 1, a second stacked core 2 and a third stacked core 3. The second stacked core 2 is stacked on the surface of the third stacked core 3, and the first stacked core 1 is stacked on the surface of the second stacked core 2. In addition, the first stacked core 1 is connected to the first pole lug 101 at both ends, the second stacked core 2 is connected to the second pole lug 201 at both ends, and the third stacked core 3 is connected to the third pole lug 301 at both ends. At the same time, the first pole lug 101, the second pole lug 201 and the third pole lug 301 are offset from each other and are all connected to the busbar 6.

[0038] 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 set at different positions, such as stacked cores with tabs centered, stacked cores with tabs offset to the left, and stacked cores with tabs offset to the right. Figure 1 In the embodiment, the second pole tab 201 is located in the middle of the busbar 6, the first pole tab 101 is located on one side of the second pole tab 201, and the third pole tab 301 is located on the other side of the second pole tab 201. The advantage of this is that the limited space is fully utilized to avoid the problem that the bending space required for the pole tabs to be bent on the same vertical line is too large.

[0039] Furthermore, combined with Figure 1 and Figure 2 It can be seen that the first pole tab 101, the second pole tab 201 and the third pole tab 301 all include guide plates ( Figure 2 A) and the tab connection piece arranged in the horizontal direction ( Figure 2 In B), the guide plate is fixedly connected to the pole tab connecting plate. In addition, the length of the guide plate is proportional to the horizontal height of the first pole tab 101, the second pole tab 201 and the third pole tab 301.

[0040] It should be noted that the length of the guide plate is related to the thickness of the multi-layer core. Figure 1 The first stacked core 1 is located at the highest layer, and its guide plate is the longest, while the third stacked core 3 is located at the lowest layer, and its guide plate is the shortest.

[0041] Furthermore, the pole ear is welded to the busbar 6, and specifically, laser welding or ultrasonic welding can be used to fix the pole ear. In addition, the positive electrode cover plate 4 and the negative electrode cover plate 5 are connected to the busbar 6 by welding or riveting, and specifically, they are fixed to the cover plate by laser welding or riveting.

[0042] Furthermore, the shapes of the busbars 6 include strip, “L”, trapezoid and “X” shapes.

[0043] It should be noted that the guide plate can be rectangular in shape. When the width of the battery cell is very wide and the number of offset core stacking layers is large, an "L"-shaped guide plate design can be used so that it can extend to the middle to the specified cover plate welding area. Trapezoidal, "X"-shaped and other design shapes all have a weak connection plate overcurrent area, which can prevent sudden large current overcurrent and ensure that the weak area can be blown first, thereby protecting the battery cell. The horizontally arranged heat dissipation overcurrent connection plate ( Figure 1 One of the functions of the busbar connecting piece 6) is to connect the various stacked core guide plates to form a main flow channel. At the same time, the large surface area has a heat dissipation effect to a certain extent.

[0044] like Figure 3As shown, a structure for improving heat dissipation is provided, wherein a heat conduction channel 7 is provided on the bottom surfaces of the positive electrode cover plate 4 and the negative electrode cover plate 5, and the heat conduction channel 7 is located directly below the bus connecting piece 6. When air flows through, the heat accumulated in the heat conduction channel 7 can be taken out, thereby achieving a certain heat dissipation effect on the bus connecting piece 6.

[0045] Figure 1 The multi-layer stacked core battery can be installed in a variety of ways, which are described below.

[0046] Installation method 1

[0047] In the stage of cutting the tabs, the tabs at different positions are cut according to the designed positions, including right offset, left offset and centered tabs, and are stacked by thermal compounding or Z stacking. The thermal compounding adopts the double diaphragm stacking method, and the Z stacking adopts the single diaphragm stacking method. The stacked tabs are closed by the downward offset method in the thickness direction. The distance between the offset closing position and the center of the single stack core is between 1 / 3h and 1 / 2h of the thickness h of the single stack core, and then ultrasonic pre-welding is performed. The pre-welding function is to close and fix the morphology of the tabs. The area is relatively small, which can be 2*half of the width of the tabs.

[0048] Cut off the excess tabs, and then ultrasonically weld the tabs with the corresponding guide plates. The weld area is calculated according to the cell capacity and the overcurrent ratio, and can be selected as 5*(tab width - 5). The stacked cores in these states are stacked in the order of tab centering to offset, such as Figure 1 As shown, the stacking order is the core stacking in the form of a center-centered tab connecting piece on the bottom layer, the core stacking in the form of a right-biased tab connecting piece on the second layer, and the core stacking in the form of a left-biased tab connecting piece on the third layer. The welded guide plates are then closed together at a suitable angle and in a manner, and the closing position is generally biased downward in the thickness direction of the core stack, in preparation for subsequent welding of the cover plate. Afterwards, the guide plates are also welded together, generally using toothless ultrasonic welding, in preparation for subsequent laser welding with the cover plate on the weld print surface.

[0049] The other pole is welded in the same way, and then the core is stacked into the shell, and the key position is positioned using tooling. Then the positive cover plate 4 and the negative cover plate 5 are welded to the guide plate. Laser welding is generally used because of its high welding efficiency and high welding strength. After the cover plate and the guide plate are welded, the guide plate, the pole ear connecting plate, etc. are bent until they are in the position of being assembled with the shell, and finally the shell and the cover plate are welded.

[0050] Installation method 2

[0051] Prepare the same stacked core with the tabs offset or centered, and then close and pre-weld the tabs on the stacked core. The closing position is generally offset by a distance in the thickness direction of the stacked core, or even completely offset to one side. After the pre-welding is completed, the excess part is cut according to the different lengths of the tabs; then the two stacked cores are placed head to head on the positive cover plate 4 or the negative cover plate 5.

[0052] Laser welding is performed, and the other pole is also biased and retracted, and ultrasonic pre-welded. The excess part of the pole lug is cut off, and the guide plate of the corresponding length is ultrasonically welded again on the pre-weld mark. The guide plate and the closed pole lug connecting plate can also be directly ultrasonically pre-welded together. This will reduce the number of steps, but the operation is slightly more difficult.

[0053] Subsequently, the core stack is closed and fixed with rubber, and then the guide plate is ultrasonically welded at the appropriate position. The core is then stacked into the shell, and the positive or negative cover and the guide plate are welded. The welding position is on the ultrasonic weld mark of the guide plate. After that, the cover, guide plate, and pole ear connecting piece are bent to the appropriate position until they are assembled on the shell, and finally the shell and the cover are welded.

[0054] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; 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 present invention.

Claims

1. A multi-layer stacked battery, characterized in that: include: A core stack assembly, a positive electrode cover plate (4) and a negative electrode cover plate (5); The stacked core assembly comprises a plurality of stacked cores, both ends of each of the stacked cores are connected with tabs, and the tabs of different layers are offset from each other; The positive electrode cover plate (4) and the negative electrode cover plate (5) are respectively installed at two ends of the stacked core; The surfaces of the positive electrode cover plate (4) and the negative electrode cover plate (5) are both provided with busbar connecting pieces (6) in contact with the pole tabs.

2. A multi-layer stacked battery according to claim 1, characterized in that: The stacked core assembly comprises a first stacked core (1), a second stacked core (2) and a third stacked core (3); The second core stack (2) is stacked on the surface of the third core stack (3); The first core stack (1) is stacked on the surface of the second core stack (2).

3. A multi-layer stacked battery according to claim 2, characterized in that: The first stacked core (1) has first pole tabs (101) connected to both ends thereof; The second stacked core (2) has second pole tabs (201) connected to both ends thereof; The third stacked core (3) has third pole tabs (301) connected to both ends.

4. A multi-layer stacked battery according to claim 3, characterized in that: The first pole lug (101), the second pole lug (201) and the third pole lug (301) are arranged offset from each other and are all connected to the busbar (6).

5. A multi-layer stacked battery according to claim 3, characterized in that: The second pole lug (201) is located in the middle of the busbar (6); The first pole lug (101) is located on one side of the second pole lug (201); The third electrode tab (301) is located on the other side of the second electrode tab (201).

6. A multi-layer stacked battery according to claim 3, characterized in that: The first pole lug (101), the second pole lug (201) and the third pole lug (301) all include a guide plate arranged in a vertical direction and a pole lug connecting plate arranged in a horizontal direction; The guide plate and the pole lug connecting plate are fixedly connected.

7. A multi-layer stacked battery according to claim 6, characterized in that: The length of the guide plate is proportional to the horizontal heights of the first pole lug (101), the second pole lug (201) and the third pole lug (301).

8. The multi-layer stacked battery according to claim 1, characterized in that: The pole lug is welded to the busbar (6).

9. The multi-layer stacked battery according to claim 1, characterized in that: The positive electrode cover plate (4) and the negative electrode cover plate (5) are both connected to the busbar connecting piece (6) by welding or riveting.

10. A multi-layer stacked battery according to any one of claims 1 to 9, characterized in that: The shapes of the busbar (6) include rectangular, "L"-shaped, trapezoidal and "X"-shaped.

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