Lithium battery cover plate welding clamping device

Abstract

The utility model discloses a welding and clamping device for a lithium battery cover plate. The welding and clamping device comprises a rack, a loading jig, a tab bending mechanism, a tab keeping mechanism and a pressing and fixing mechanism. According to the utility model, double-lamination tabs of a double-lamination laminated battery can be bent, paired, clamped and fixed before laser welding, so that the tabs are wrapped on the outer sides of cover plate pins, laser welding can be directly carried out on the tabs conveniently, the double-lamination battery can be effectively treated, the bent tabs are prevented from being tilted and folded during laser welding of the cover plate, and the working efficiency of the battery is improved. And the welding accuracy, yield and qualification rate are guaranteed, it is guaranteed that upper and lower tabs on the single side can be effectively welded, and the welding qualification rate of an assembly line is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of square double-laminated lithium battery production, in particular to a lithium battery cover welding clamping device. Background Art

[0002] Lithium-ion battery is a secondary battery (rechargeable battery), which mainly relies on the movement of lithium ions between the positive and negative electrodes to work. Lithium-ion batteries are widely used in biochemistry as energy sources for equipment due to their high energy, long cycle times, and high efficiency. Lithium iron manganese phosphate batteries are an emerging lithium-ion battery on the market. Lithium iron phosphate batteries are limited by their one-dimensional lithium ion diffusion channels and insulating PO4 polyanion framework, resulting in low ion conductivity, especially lower electronic conductivity than lithium iron phosphate. Lithium iron manganese phosphate not only has all the advantages of lithium iron phosphate, but also has better electronic conductivity and better rate and cycle performance.

[0003] Since the structure of lithium iron phosphate battery is the same as that of lithium iron phosphate battery, and the composition of the positive electrode material is also similar, it has higher stability. The biggest difference is that the lithium iron phosphate battery has additional manganese material added, but it does not affect its safety. The thermal stability and safety of the battery are as good as those of lithium iron phosphate battery.

[0004] Lithium manganese iron phosphate batteries have the same cycle life as lithium iron phosphate batteries, both of which are more than 2,000 charge and discharge cycles. If there is a good battery management strategy, then its life can theoretically reach up to 3,000 times, which is higher than that of ternary lithium batteries. For the development process of lithium manganese iron phosphate battery cell equipment, lithium battery stacking technology is used, with positive and negative tabs on the left and right, making full use of battery space and having a higher capacity density. At present, the lithium manganese iron phosphate battery stacking process battery has tabs on both sides, and the cover plate connecting pieces on both sides are welded and then the sealing perimeter is fully welded twice. The number of welding times is large, the laser cost is high, and it also affects the overall production line production efficiency and pass rate.

[0005] In the prior art, pins are often added to the positive and negative poles of one side of the cover plate, and then the pins and the pole ears are laser welded. This method is mainly for welding single laminations, and it is necessary to protect the connection piece overlap for welding. However, it is difficult to achieve welding for double laminations, and the process steps are cumbersome, and the stability and safety after welding are difficult to guarantee.

[0006] In reality, a device is needed that can bend, pair, clamp and fix the tabs of double-laminated batteries before laser welding of the cover tabs, so that the tabs are wrapped around the outside of the pins, and the battery cell and the cover are fixed before laser welding is performed directly on the tabs. This device can be effectively compatible with double-laminated batteries, and can ensure that the bent tabs will not warp up or fold during laser welding of the cover, thereby ensuring the accuracy, yield and pass rate of welding, and is more effectively compatible with the pressure head of the cover welding, ensuring that the upper and lower tabs on one side can be effectively welded, thereby improving the welding pass rate of the assembly line. Utility Model Content

[0007] The utility model aims to provide a lithium battery cover welding clamping device, which can be used to bend, pair, clamp and fix the double-laminated tabs of a double-laminated square battery, so that the upper and lower tabs on one side can be effectively welded, thereby improving the welding qualification rate.

[0008] The purpose of the utility model can be achieved through the following technical solutions: A lithium battery cover welding clamping device, comprising a stand, on which is provided:

[0009] Loading jig for placing A stack, B stack and cover plate;

[0010] The tab bending mechanism is used to bend the positive and negative tabs of the placed A stack and B stack towards each other;

[0011] The tab holding mechanism fixes the A stack, B stack and cover plate after the tab is bent.

[0012] Optionally: a pressing and fixing mechanism is also included to press and fix the A stack, B stack and cover plate after placement.

[0013] Optionally: the tab bending mechanism includes:

[0014] A negative electrode upper folding ear assembly and a negative electrode lower folding ear assembly, wherein the negative electrode upper folding ear assembly and the negative electrode lower folding ear assembly are controlled by a negative electrode folding ear solenoid valve group;

[0015] The positive electrode upper folding ear assembly and the positive electrode lower folding ear assembly are controlled by a positive electrode folding ear solenoid valve group.

[0016] Optionally: the tab holding mechanism includes:

[0017] The pressure rod, when it pops up, presses and fixes the A stack, B stack and cover plate after the tab is bent, and releases the fixation when it falls.

[0018] The spring locking assembly is used to control the rise or fall of the pressure rod.

[0019] Optionally, when the positive and negative tabs of the A stack and the B stack are bent toward each other, the positive and negative tabs of the A stack and the B stack are respectively covered at the pins of the cover plate.

[0020] Optionally, the A stack, B stack and cover plate are placed in the loading fixture in the order of first placing the A stack, then placing the cover plate, and finally placing the B stack.

[0021] Beneficial effects of the utility model:

[0022] 1. The utility model can bend, pair, clamp and fix the double-laminated tabs of double-laminated laminated batteries before laser welding, so that the tabs are wrapped around the outside of the cover pins, which is convenient for direct laser welding on the tabs. The double-laminated batteries can be effectively processed to ensure that the bent tabs will not warp up or fold during cover laser welding, thereby ensuring the accuracy, yield and qualified rate of welding, ensuring that the upper and lower tabs on one side can be effectively welded, and improving the welding qualified rate of the assembly line.

[0023] 2. The utility model adopts an integrated device of folding pole ears and double-stack matching fixtures, which saves the complicated transportation process, reduces the failure rate, and has strong compatibility and is easy to match with the cover plate laser welding machine device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a structural schematic diagram of a lithium battery cover welding clamping device of the utility model;

[0025] Figure 2 For this utility model Figure 1 Side view of

[0026] Figure 3 For this utility model Figure 1 A top view of

[0027] Figure 4 For this utility model Figure 1 Rear view of

[0028] Figure 5 This is a schematic diagram of the structure of the battery cell tab before bending of the utility model;

[0029] Figure 6 This is a schematic diagram of the structure of the battery cell after the pole ear is bent;

[0030] Figure 7 It is a structural schematic diagram of the pressing and fixing mechanism and the tab holding mechanism of the utility model;

[0031] Figure 8 It is a structural schematic diagram of the pressing and fixing mechanism and the tab retaining mechanism of the utility model.

[0032] 100. Stand;

[0033] 200. Loading fixture;

[0034] 300, pressing and fixing mechanism; 310, clamping sheet; 320, pushing plate;

[0035] 400, pole ear bending mechanism; 410, negative pole upper folding ear assembly; 420, negative pole lower folding ear assembly; 430, negative pole folding ear solenoid valve group; 440, positive pole upper folding ear assembly; 450, positive pole lower folding ear assembly; 460, positive pole folding ear solenoid valve group; 470, folding corner piece;

[0036] 500, tab holding mechanism; 510, pressure rod; 520, spring locking assembly;

[0037] 600, battery cell; 610, A stack; 611, positive ear; 612, negative ear; 613, long side; 614, short side; 620, B stack; 630, cover; 631, pin. DETAILED DESCRIPTION

[0038] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar symbols throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0039] Traditional laminated batteries are mostly single-laminated. When the left and right side covers of the positive and negative electrode structures are laser welded, the clamping device is not compatible with the double-laminated structure, and the ear bending and jig stack pairing are separated. They are bent first and then transferred to the jig for pairing. The process is cumbersome, the failure rate is high, and the compatibility is limited. To address the above problems, in the face of double-laminated battery production, an integrated device for folding the ear and pairing the double laminate is needed, which can save the complicated transportation process, reduce the failure rate, and has strong compatibility and is easy to match with the laser welding machine device.

[0040] Therefore, in view of the above problems, a lithium battery cover welding clamping device is proposed. Figure 1 , 2 As shown in , 3 and 4 , the device includes a stand 100 , and a loading fixture 200 is connected to the stand 100 .

[0041] The working surface of the loading jig 200 is set horizontally. The loading jig 200 is used to place the A stack 610, the B stack 620 and the cover plate 630. When in use, the double stacks are placed on the loading jig 200 in the order of first placing the A stack 610, then placing the cover plate 630, and finally placing the B stack 620. Figure 1 , 56, at this time, the A stack 610 and the B stack 620 are located between the two pins 631 of the cover plate 630, the negative pole ear 612 of the A stack 610 and the negative pole ear 612 of the B stack 620 are located on the same side, and the positive pole ear 611 of the A stack 610 and the positive pole ear 611 of the B stack 620 are located on the same side.

[0042] like Figure 7 , 8 The pressing and fixing mechanism 300 is located on the side of the long side 613 of the A stack 610 and the B stack 620 away from the cover plate 630. The pressing and fixing mechanism 300 fixes the A stack 610 and the B stack 620 along the long side 613 through the clamping plate 310. The pressing and fixing mechanism 300 presses and fixes the A stack 610 and the B stack 620 and the cover plate 630 along the short side 614 through the pushing plate 320.

[0043] For the fixedly placed A stack 610 and B stack 620, the tab bending mechanism 400 is used to bend the positive and negative tabs of the A stack 610 and the B stack 620 toward each other, such as Figure 1 , 4 As shown, the tab bending mechanism 400 includes:

[0044] The negative electrode upper folding ear assembly 410 and the negative electrode lower folding ear assembly 420, the negative electrode upper folding ear assembly 410 is located on the upper side of the negative electrode ear 612 of the B stack 620, and the negative electrode lower folding ear assembly 420 is located on the lower side of the negative electrode ear 612 of the A stack 610, the negative electrode upper folding ear assembly 410 and the negative electrode lower folding ear assembly 420 are controlled by a negative electrode folding ear solenoid valve group 430, when the A stack 610, the B stack 620 and the cover plate 630 are placed, the negative electrode upper folding ear assembly 410 and the negative electrode lower folding ear assembly 420 are controlled by the negative electrode folding ear solenoid valve group 430, the negative electrode upper folding ear assembly 410 and the negative electrode lower folding ear assembly 420 approach the negative electrode ears 612 of the A stack 610 and the B stack 620 respectively, and the negative electrode ears 612 are squeezed by the folding piece 470 to achieve the bending of the negative electrode ears 612.

[0045] The positive electrode upper folding ear assembly 440 and the positive electrode lower folding ear assembly 450, the positive electrode upper folding ear assembly 440 is located on the upper side of the positive electrode ear 611 of the B stack 620, and the positive electrode lower folding ear assembly 450 is located on the lower side of the positive electrode ear 611 of the A stack 610, the positive electrode upper folding ear assembly 440 and the positive electrode lower folding ear assembly 450 are controlled by a positive electrode folding ear solenoid valve group 460, when the A stack 610, the B stack 620 and the cover plate 630 are placed, the positive electrode upper folding ear assembly 440 and the positive electrode lower folding ear assembly 450 are controlled by the positive electrode folding ear solenoid valve group 460, the positive electrode upper folding ear assembly 440 and the positive electrode lower folding ear assembly 450 approach the positive electrode ears 611 of the A stack 610 and the B stack 620 respectively, and the positive electrode ears 611 are squeezed by the folding piece 470 to achieve the bending of the positive electrode ears 611.

[0046] The tab holding mechanism 500, such as Figure 7 , 8 As shown, the tab retaining mechanism 500 includes a pressing rod 510 and a spring locking assembly 520 .

[0047] like Figure 8 As shown, when the pole ears on both sides of the A stack 610 and the B stack 620 are bent, the pressure rod 510 is controlled to spring up by the spring locking assembly 520, and the bent pole ears are pressed and fixed, so that the pole ears and the pins 631 of the cover plate 630 are abutted together, which is convenient for subsequent laser welding to weld the pole ears and the pins 631 together and ensure welding stability.

[0048] like Figure 7 As shown, when welding is completed, the A stack 610 and the B stack 620 are welded together with the cover plate 630 to form an integral battery cell 600, and the pressure rod 510 is controlled to fall down by the spring locking assembly 520, and the pressing and fixing mechanism 300 is withdrawn, so that the battery cell 600 can be taken out as a whole for subsequent processes.

[0049] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes according to the technical scheme and concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0050] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0051] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0052] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

Claims

1. A lithium battery cover welding clamping device, characterized in that: The invention comprises a stand (100), on which is arranged: A loading jig (200) is used to place the A stack (610), the B stack (620) and the cover plate (630); A tab bending mechanism (400) is used to bend the positive and negative tabs of the placed A stack (610) and B stack (620) towards each other; The tab holding mechanism (500) fixes the A stack (610) and the B stack (620) and the cover plate (630) after the tab is bent.

2. A lithium battery cover welding clamping device according to claim 1, characterized in that: It also includes a pressing and fixing mechanism (300) for pressing and fixing the A stack (610), the B stack (620) and the cover plate (630) after placement.

3. A lithium battery cover welding clamping device according to claim 1, characterized in that: The tab bending mechanism (400) comprises: A negative electrode upper folding ear assembly (410) and a negative electrode lower folding ear assembly (420), wherein the negative electrode upper folding ear assembly (410) and the negative electrode lower folding ear assembly (420) are controlled by a negative electrode folding ear solenoid valve assembly (430); A positive electrode upper folding ear assembly (440) and a positive electrode lower folding ear assembly (450), wherein the positive electrode upper folding ear assembly (440) and the positive electrode lower folding ear assembly (450) are controlled by a positive electrode folding ear solenoid valve assembly (460).

4. A lithium battery cover welding clamping device according to claim 1, characterized in that: The tab holding mechanism (500) comprises: The pressure rod (510) presses and fixes the A stack (610) and the B stack (620) and the cover plate (630) after the tabs are bent when it is popped up, and releases the fixation when it falls down; The spring locking assembly (520) is used to control the rising or falling of the pressing rod (510).

5. A lithium battery cover welding clamping device according to claim 1, characterized in that: When the positive and negative electrode ears of the A stack (610) and the B stack (620) are bent toward each other, the positive and negative electrode ears of the A stack (610) and the B stack (620) are respectively covered at the pins (631) of the cover plate (630).

6. A lithium battery cover welding clamping device according to claim 1, characterized in that: The A stack (610), the B stack (620) and the cover plate (630) are placed in the loading jig (200) in the following order: the A stack (610) is placed first, the cover plate (630) is placed second, and the B stack (620) is placed last.

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