battery

Abstract

The utility model belongs to power battery technical field discloses battery, including shell, at least two electric cores and apron, shell is provided with opening, two electric cores all set up in the shell, is provided with the tab on the electric core, apron covers in the opening, is provided with the pole on the apron, the projection of at least two electric cores same polarity tab on the same polarity pole does not coincide, at least two electric cores same polarity tab and same polarity pole are connected through a connecting solder mark, and the connecting solder mark covers at least two same polarity tabs simultaneously. Through make at least two electric cores same polarity tab and same polarity pole be connected through a connecting solder mark, can simplify the connecting structure, and simplify the connecting procedure, and still can shorten the current path, promote the overcurrent capacity.

Description

Technical Field

[0001] This utility model relates to the field of power battery technology, and in particular to a battery. Background Technology

[0002] A single battery cell generally includes a casing, two cells, and a cover plate. The two cells are located inside the casing, and the cover plate seals the top opening of the casing. Each cell has a positive electrode tab and a negative electrode tab, and the cover plate has a positive terminal and a negative terminal. The positive electrode tabs of both cells are connected to the positive terminal, and the negative electrode tabs of both cells are connected to the negative terminal.

[0003] In related technologies, the connection method between the tabs and the terminals is as follows: the tabs are first pre-connected using ultrasonic welding, and then the two positive tabs are welded to the positive terminals using laser welding to form two positive connection stamps. Similarly, the two negative tabs are welded to the negative terminals using laser welding to form two negative connection stamps. This connection method requires two connection stamps to connect two tabs and terminals of the same polarity, resulting in a complex structure and complex process; furthermore, the current path is long, and the current carrying capacity is insufficient. Utility Model Content

[0004] The purpose of this invention is to provide a battery that simplifies the connection structure and process by connecting the tabs and terminals of the same polarity of two cells through a connecting solder joint; it also shortens the current path and improves the overcurrent capacity.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] The battery includes:

[0007] The outer casing has an opening;

[0008] At least two battery cells are disposed inside the housing, and each battery cell is provided with a tab.

[0009] A cover plate is provided to cover the opening, and an pole post is provided on the cover plate;

[0010] At least two of the battery cells' tabs of the same polarity do not overlap on the same polarity terminal post, and at least two of the battery cells' tabs of the same polarity are connected to the same polarity terminal post by a connection solder mark, and the connection solder mark simultaneously covers at least two of the same polarity tabs.

[0011] The beneficial effects of this utility model are:

[0012] This utility model provides a battery, including a casing, at least two battery cells, and a cover plate. The casing has an opening. At least two battery cells are disposed inside the casing, and each cell has a tab. The cover plate closes to the opening and has terminals. The projections of the tabs of the same polarity of the at least two battery cells onto the terminals of the same polarity do not overlap. The tabs of the at least two battery cells and the terminals of the same polarity are connected by a connecting solder joint, and the connecting solder joint simultaneously covers the at least two tabs of the same polarity. By connecting the tabs of the at least two battery cells and the terminals of the same polarity through a connecting solder joint, the connection structure and connection process are simplified; furthermore, the current path is shortened, and the overcurrent capacity is improved. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the battery structure provided in an embodiment of the present invention;

[0014] Figure 2 This is a cross-sectional view of the battery provided in an embodiment of this utility model;

[0015] Figure 3 This is a schematic diagram of the structure when welding the battery cell tab to the cover plate pole, as provided in this embodiment of the utility model.

[0016] In the picture:

[0017] 10. Outer casing; 20. Cell body; 21. Tab; 30. Cover plate; 31. Terminal post; 311. Substrate; 312. Outer sheath; 32. Explosion-proof valve; 41. First insulating component; 42. Second insulating component; 50. Pre-welded stamp; 60. Connecting stamp. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0019] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0020] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0021] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0022] like Figures 1 to 3 As shown, this utility model provides a battery, which can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this embodiment is not limited to this. A battery typically includes a battery casing, a cell, and an electrolyte. The battery casing is used to house the cell and electrolyte, and generally includes an outer shell and a cover plate. At least one positive electrode post and at least one negative electrode post are disposed on the outer shell and / or the cover plate. The cell includes one or more electrode assemblies, which are formed by stacking or winding positive electrode plates, negative electrode plates, and a separator. The separator is located between adjacent positive and negative electrode plates to insulate them, and at least one end of the electrode assembly has a tab, which is electrically connected to the electrode post.

[0023] In this embodiment, the battery includes a casing 10, at least two battery cells, and a cover plate 30. The casing 10 is located on the outermost side of the battery, and one end of the casing 10 has an opening to facilitate the installation of the battery cells into the casing 10. The casing 10 protects the battery cells from external impurities, thereby improving the lifespan of the battery cells. The casing 10 can be made of, but is not limited to, aluminum alloy or steel, specifically aluminum-manganese alloy, aluminum-magnesium alloy, stainless steel, nickel-plated steel, etc. The cover plate 30 covers the opening, and the cover plate 30 and the casing 10 together form a receiving cavity, in which the battery cells are placed. The cover plate 30 can be made of, but is not limited to, aluminum alloy or steel.

[0024] It should be noted that the battery cell can be constructed as a laminated cell or a wound cell; no specific limitation is made here. A laminated cell is formed by stacking positive electrode plates, negative electrode plates, and a separator. Adjacent positive electrode plates and adjacent negative electrode plates are discontinuously arranged. The separator can be continuously arranged, such as in a Z-shaped laminated cell, or it can be discontinuously arranged. A wound cell is formed by winding positive electrode plates, negative electrode plates, and a separator.

[0025] The battery cell includes a cell body 20 and a tab 21. The tab 21 extends from the cell body 20 and serves as the current output terminal inside the cell. A terminal post 31 is provided on the cover plate 30. The tab 21 is used to make electrical connections with the terminal post 31 on the cover plate 30. The terminal post 31 serves as the battery current output terminal and is used to connect to external busbars, etc., to realize series and parallel connection between batteries.

[0026] Each battery cell has a positive electrode tab and a negative electrode tab. It can be understood that the positive electrode tab is electrically connected to the positive electrode plate, and the negative electrode tab is electrically connected to the negative electrode plate. The cover plate 30 is provided with a positive electrode post and a negative electrode post. The positive electrode tabs of both battery cells are connected to the positive electrode post, and the negative electrode tabs of both battery cells are connected to the negative electrode post.

[0027] It should be noted that the material of the electrode post 31 must be the same as the material of the corresponding electrode tab 21. In a specific embodiment, the positive electrode tab is made of aluminum, and the negative electrode tab is made of copper. Correspondingly, the material of the positive electrode post must be aluminum, and the material of the negative electrode post must be copper. Alternatively, the positive and negative electrode posts can also be composed of a substrate 311 and an outer cladding layer 312. The outer cladding layer 312 covers the side of the substrate 311 facing the electrode tab 21. The material of the substrate 311 of both the positive and negative electrode posts can be aluminum, the material of the outer cladding layer 312 of the positive electrode post is aluminum, and the material of the outer cladding layer 312 of the negative electrode post is copper.

[0028] In this embodiment, the number of battery cells is two. In other embodiments, the number of battery cells may be more than two, and is not limited to this embodiment.

[0029] In this embodiment, the two electrodes 21 of the same polarity of the two battery cells are connected to the terminals 31 of the same polarity through a connection solder mark 60, and the connection solder mark 60 covers both electrodes 21 of the same polarity. Specifically, the two positive electrodes are connected to the positive terminals through a positive connection solder mark 60, and the positive connection solder mark 60 covers both positive electrodes; the two negative electrodes are connected to the negative terminals through a negative connection solder mark 60, and the negative connection solder mark 60 covers both negative electrodes. By connecting the electrodes 21 of the same polarity of the two battery cells to the terminals 31 of the same polarity through a connection solder mark 60, the connection structure and connection process can be simplified; it can also shorten the current path and improve the overcurrent capacity.

[0030] In some embodiments, the area of ​​the connecting solder mark 60 is 60 mm². 2 -200mm 2 For example, the area of ​​the connecting solder mark 60 can be 60mm². 2 70mm 2 80mm 2 90mm 2 100mm 2 110mm 2 120mm 2 130mm 2 140mm 2 150mm 2 160mm 2 170mm 2 180mm 2 190mm 2 Or 200mm 2 The larger the area of ​​the solder joint 60, the greater the current carrying capacity, but the higher the tab 21 needs to extend. A larger tab 21 height also increases the internal resistance, and damage to the tab 21 is more likely during manufacturing. Therefore, by setting the area of ​​the solder joint 60 to 60mm²... 2 -200mm 2 This ensures both the current carrying capacity of the connection solder 60 and prevents the tab 21 from protruding too high.

[0031] In some embodiments, the areas of the solder marks 60 on the two electrodes 21 of the same polarity are equal. In some embodiments, the areas of the solder marks 60 on the two electrodes 21 of the same polarity are not equal, wherein the area of ​​the solder mark 60 on the electrode 21 with the smaller area accounts for 0.3-0.5 of the total area of ​​the solder mark 60, for example, it can be 0.3, 0.4, or 0.5. Specifically, if the positive electrode solder mark 60 covers an area A of one positive electrode electrode of a battery cell and an area B of another positive electrode electrode of a battery cell, then the ratio of A to A+B is 0.3-0.5; if the negative electrode solder mark 60 covers an area C of one negative electrode electrode of a battery cell and an area D of another negative electrode electrode of a battery cell, then the ratio of C to C+D is 0.3-0.5. Through the above settings, the connection strength between the two electrodes 21 of the same polarity and the terminal post 31 of the same polarity can be guaranteed.

[0032] Optionally, a gap of 0-3mm is provided between the two tabs 21 of the same polarity to prevent the gap from being too large and affecting the current flow area. The thickness of the connecting solder 60 to the gap between the two tabs 21 of the same polarity is 0.1mm-1mm to ensure the strength of the connecting solder 60 in the gap between the two tabs 21 of the same polarity. For example, the thickness of the connecting solder 60 to the gap between the two tabs 21 of the same polarity can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 1mm, etc. It should be noted that the thickness direction of the connecting solder 60 is the thickness direction of the cover plate 30, or the height direction of the battery.

[0033] When assembling the battery, first place the cover plate 30 with its inner wall facing upwards, and fix the cover plate 30 with the support and limiting mechanism; then place the two battery cells horizontally or at an angle, and fix the battery cells with the support and limiting mechanism; then connect the same polarity tabs 21 of the two battery cells to the same polarity terminals 31, referring to... Figure 3 Then, bend the tab 21 to close the two cells, and install the closed cells into the housing 10. Finally, connect the housing 10 to the cover plate 30, as shown in the reference. Figure 1 and Figure 2 .

[0034] Specifically, the methods for connecting the cell tabs to the cover plate terminals include:

[0035] First, the tabs 21 of the two battery cells are pre-soldered. Specifically, the positive tab of each battery cell is pre-soldered, so that the multiple positive tabs of each battery cell are formed into a whole positive tab, and a pre-soldering mark 50 is formed; the negative tab of each battery cell is pre-soldered, so that the multiple negative tabs of each battery cell are formed into a whole negative tab, and a pre-soldering mark 50 is formed.

[0036] Understandably, the multi-layer tabs 21 produced from the winding or stacking of battery cells are loose and uneven. Pre-welding integrates these dispersed multi-layer tabs 21 into a robust, low-resistance, and neat whole. When subsequently welding them to the terminals 31, the object of operation changes from a "dispersed component" to a "whole unit," resulting in a wider welding process window and extremely high consistency. Furthermore, pre-welding ensures that all tabs 21 are connected in parallel along the current path with consistent connection resistance. This allows current to flow evenly through each layer of tabs 21, preventing concentrated current flow through a few layers and thus avoiding localized overheating, thereby improving the battery's rate performance and safety.

[0037] In some embodiments, the number of layers of the tab 21 is 30 to 180. For example, the number of layers of the tab 21 can be 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170 or 180 layers, etc. In some embodiments, the thickness of the positive electrode monolithic tab is 8μm-15μm, for example, the thickness of the positive electrode monolithic tab can be 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm or 15μm, etc.; the thickness of the negative electrode monolithic tab is 2μm-8μm, for example, the thickness of the negative electrode monolithic tab can be 2μm, 2.5μm, 3μm, 3.5μm, 4μm, 4.5μm, 5μm, 5.5μm, 6μm, 6.5μm, 7μm, 7.5μm or 8μm, etc.

[0038] In some embodiments, ultrasonic welding can be used to pre-weld the multilayer tabs 21. This involves using the vibrational energy of high-frequency ultrasound, transmitted through a welding head to the layers of tabs 21 to be welded. Under the combined action of pressure and vibration, plastic flow and atomic diffusion occur at the interface between the tabs 21, forming a strong weld joint. Alternatively, laser welding can be used to pre-weld the multilayer tabs 21. This involves using a high-energy-density laser beam as a heat source to irradiate the connection point of the tabs 21, causing localized melting or even vaporization of the material. After the molten material cools and solidifies, a permanent connection is formed.

[0039] In some embodiments, along the extension direction of the tab 21, the pre-soldering mark 50 at least partially covers the end of the tab 21. In this embodiment, the width of the pre-soldering mark 50 along the extension direction of the tab 21 is 3mm-20mm. For example, the width of the pre-soldering mark 50 can be 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, or 20mm, etc. It should be noted that the extension direction of the tab 21 refers to the line connecting the intersection of the tab 21 and the post 31 to the pre-soldering mark 50 of the tab 21. The extension directions of the two tabs 21 are at a 180-degree angle to each other.

[0040] In some embodiments, the area of ​​the pre-welded solder mark 50 is 80 mm². 2 -300mm 2 For example, the area of ​​the pre-soldering stamp 50 can be 80mm². 2 90mm 2 100mm 2 110mm 2 120mm 2 130mm 2 140mm2 150mm 2 160mm 2 170mm 2 180mm 2 190mm 2 200mm 2 210mm 2 220mm 2 230mm 2 240mm 2 250mm 2 260mm 2 270mm 2 280mm 2 290mm 2 Or 300mm 2 wait.

[0041] After pre-soldering the tabs 21 of the two battery cells, the tabs 21 of the same polarity of the two battery cells are placed on the terminals 31 of the same polarity, with a gap between the tabs 21 of the same polarity of the two battery cells. Specifically, the positive tabs of the two battery cells are placed on the positive terminal, and the negative tabs of the two battery cells are placed on the negative terminal, with a gap between the two positive tabs and a gap between the two negative tabs.

[0042] After placing the two identical polarity tabs 21 onto the identical polarity terminal 31, the two identical polarity tabs 21 are simultaneously welded to the identical polarity terminal 31 in a single welding operation, forming a connection solder mark 60 that covers both identical polarity tabs 21. Specifically, the two positive electrode tabs are simultaneously welded to the positive electrode terminal in a single welding operation, forming a positive connection solder mark 60 that covers both positive electrode tabs; similarly, the two negative electrode tabs are simultaneously welded to the negative electrode terminal in a single welding operation, forming a negative connection solder mark 60 that covers both negative electrode tabs.

[0043] In some embodiments, the connecting solder stamp 60 is completely located within the pre-soldering solder stamp 50. Alternatively, a portion of the connecting solder stamp 60 extends beyond the pre-soldering solder stamp 50. The area of ​​the connecting solder stamp 60 extending beyond the pre-soldering solder stamp 50 is less than 2 / 3 of the total area of ​​the connecting solder stamp 60. This configuration ensures that the entire tab 21 is welded to the electrode post 31, resulting in a wider welding process window and higher consistency compared to connecting discrete tabs 21 to the electrode post 31.

[0044] In some embodiments, the ratio of the area of ​​the solder mark 60 connected to a tab 21 to the area of ​​the pre-soldered solder mark 50 is 0.2-0.8, for example, the ratio can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 or 0.8, etc.

[0045] Optionally, the two electrodes 21 of the same polarity and the electrode post 31 of the same polarity are welded together by ultrasonic torsion welding. The principle of ultrasonic torsion welding is to use ultrasonic vibration and torsion to weld two or more metal parts together. Ultrasonic vibration can generate high-frequency mechanical vibration. This high-frequency vibration is transmitted to the upper metal part through the welding head, causing it to reciprocate at high speed relative to the lower metal part with a very small amplitude (micrometer level). The friction will destroy and remove oxides and contaminants on the metal surface. The interface friction will generate local heat, raising the metal temperature. Under the combined action of pressure and vibration, metal atoms undergo plastic flow and interdiffusion at the interface, ultimately forming a strong solid metallurgical bond at the contact surface of the two metal parts.

[0046] By employing ultrasonic torsion welding, the height of the tab 21 extending beyond the battery cell can be reduced, thereby lowering the internal resistance of the tab 21 and preventing damage to the tab 21 during manufacturing, thus improving manufacturing yield. In this embodiment, the height of the tab 21 extending beyond the battery cell is less than or equal to 40mm.

[0047] The connecting weld 60 formed by ultrasonic torsion welding is recessed into the surface of the tab 21, and the connecting weld 60 includes a plurality of recesses of one shape or a combination of shapes. Optionally, the depth of the connecting weld 60 recessed into the surface of the tab 21 is 0.2mm-1mm, for example, it can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm, etc.

[0048] Alternatively, laser welding can be used when welding two tabs 21 of the same polarity to poles 31 of the same polarity. The principle of laser welding is to use a high-energy-density laser beam as a heat source to irradiate the connection point of the tabs 21, causing the material to locally melt or even vaporize. After the molten material cools and solidifies, a permanent connection is formed. The weld mark formed by laser welding protrudes from the surface of the tabs 21.

[0049] Furthermore, the battery in this embodiment also includes a flux sheet, which is disposed on the same polarity tabs 21 of the two cells, and the connection solder mark 60 is located on the flux sheet. That is, a positive flux sheet is disposed on the positive tab of the two cells, and the positive connection solder mark 60 is located on the positive flux sheet; a negative flux sheet is disposed on the negative tab of the two cells, and the negative connection solder mark 60 is located on the negative flux sheet. Specifically, before welding the two same polarity tabs 21 to the same polarity terminals 31, the method further includes: placing the flux sheet on the two same polarity tabs 21, so that the flux sheet covers the two same polarity tabs 21 simultaneously. Welding the two same polarity tabs 21 to the same polarity terminals 31 specifically involves welding on the flux sheet. That is, a positive electrode flux is placed on each of the two positive electrode tabs, covering both positive electrode tabs simultaneously, and welding between the two positive electrode tabs is performed on the positive electrode flux. Similarly, a negative electrode flux is placed on each of the two negative electrode tabs, covering both negative electrode tabs simultaneously, and welding between the two negative electrode tabs and the negative electrode post is performed on the negative electrode flux. By adding flux, the connection strength can be improved, and the welding yield can be increased. Furthermore, when welding the tabs 21 and the post 31 using ultrasonic torsion welding, since this welding method requires applying torque to the tabs 21, there is a possibility that the pre-welded tabs 21 may tear. By adding flux and performing welding on the flux, the torque can be applied to the flux, thereby avoiding the torque being applied directly to the tabs 21, effectively reducing the probability of the tabs 21 tearing.

[0050] The material of the flux tabs must be the same as that of the tabs 21. In a specific embodiment, the positive tab is made of aluminum, and the negative tab is made of copper. Correspondingly, the flux tabs placed on the two positive tabs are made of aluminum, and the flux tabs placed on the two negative tabs are made of copper.

[0051] Optionally, the area of ​​the flux pad is greater than or equal to the area of ​​the connecting solder mark 60, so that it falls completely on the flux pad when the soldering head applies torque, further reducing the probability of the tab 21 tearing. In some embodiments, the ratio of the area of ​​the connecting solder mark 60 to the area of ​​the flux pad is 0.7-0.9, for example, the ratio of the area of ​​the connecting solder mark 60 to the area of ​​the flux pad can be 0.7, 0.75, 0.8, 0.85 or 0.9, etc.

[0052] Optionally, the thickness of the flux sheet is 0.05mm-0.4mm. For example, the thickness of the flux sheet can be 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, or 0.4mm, etc. If the flux sheet is too thin, it is easily damaged and cannot effectively protect the tab 21; if the flux sheet is too thick, it will affect the welding effect. By setting the thickness of the flux sheet to 0.05mm-0.45mm, damage to the flux sheet can be avoided, effectively protecting the tab 21, while ensuring the welding effect.

[0053] In some embodiments, when the number of tab layers is less than 100, flux can be used or not. When the number of tab layers exceeds 100, flux is required. Specifically, when the number of tab layers is 100-130, the flux thickness is 0.05mm-0.15mm; when the number of tab layers is 130-160, the flux thickness is 0.15mm-0.25mm; when the number of tab layers is 160-170, the flux thickness is 0.25mm-0.35mm; and when the number of flux layers is 170-180, the flux thickness is 0.35mm-0.45mm.

[0054] Optionally, the shape of the flux pad can be, but is not limited to, circular, polygonal, etc.

[0055] In addition, a first insulating element 41 is provided between the inner wall of the cover plate 30 and the top of the battery cell to prevent direct contact between the battery cell and the cover plate 30 and avoid short circuits. The first insulating element 41 needs to have a certain mechanical strength and toughness because the battery cell will expand and contract slightly during charging and discharging, and the battery will vibrate during transportation and use. The first insulating element 41 can prevent damage due to squeezing, friction or vibration. Even if the battery cell expands, it can maintain an effective isolation distance to prevent the first insulating element 41 from being punctured or worn. The first insulating element 41 is generally designed in the form of a bracket, which can accurately fix the position of the battery cell and the tab 21, ensure the alignment of the tab 21 and the terminal 31, and prevent the tab 21 from being excessively bent and contacting parts that should not be in contact. In addition, a second insulating element 42 is provided between the terminal 31 and the hole wall of the terminal hole of the cover plate 30 to prevent direct contact between the terminal 31 and the cover plate 30 and avoid short circuits.

[0056] An explosion-proof valve 32 is installed on the cover plate 30. Under abusive conditions (such as overcharging, overheating, or short circuit), a violent chemical reaction occurs inside the battery, generating a large amount of heat and gases (such as carbon dioxide, carbon monoxide, and hydrocarbon gases). This causes a sharp rise in internal pressure and temperature. If these gases and pressures cannot be released, the outer casing 10 will eventually be unable to withstand the pressure and a violent physical explosion will occur. The explosion-proof valve 32 is designed as the weakest point of the outer casing 10. Its burst pressure is precisely calculated. When the internal pressure reaches a critical value, the explosion-proof valve 32 will preferentially rupture or open at a preset position, forming a controllable venting channel to allow high-pressure gases to be discharged in an orderly manner, quickly releasing internal pressure and gases, thereby preventing the battery from undergoing a more dangerous explosion or violent combustion.

[0057] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery, characterized in that, include: The outer casing (10) has an opening; At least two battery cells are disposed inside the housing (10), and each battery cell is provided with a tab (21); A cover plate (30) is provided to cover the opening, and a pole post (31) is provided on the cover plate (30); At least two of the same polarity tabs (21) of the battery cells do not overlap on the same polarity terminal post (31). At least two of the same polarity tabs (21) of the battery cells are connected to the same polarity terminal post (31) through a connection solder mark (60), and the connection solder mark (60) simultaneously covers at least two of the same polarity tabs (21).

2. The battery according to claim 1, characterized in that, The area of ​​the connecting solder mark (60) is 60 mm². 2 -200mm 2 .

3. The battery according to claim 1, characterized in that, The areas of the solder marks (60) on at least two tabs (21) of the same polarity are equal.

4. The battery according to claim 1, characterized in that, The areas of the connecting solder marks (60) on at least two tabs (21) of the same polarity are not equal, and the area of ​​the connecting solder mark (60) on the tab (21) with the smaller area accounts for 0.3-0.5 of the total area of ​​the connecting solder mark (60).

5. The battery according to claim 1, characterized in that, The tabs (21) of at least two of the cells extend in different directions.

6. The battery according to claim 1, characterized in that, The gap between the two electrodes (21) of the same polarity of the two cells is 0-3 mm.

7. The battery according to claim 1, characterized in that, The thickness of the gap between the connecting solder mark (60) and the tabs (21) of the same polarity of the two battery cells is 0.1mm-1mm.

8. The battery according to claim 1, characterized in that, The height of the tab (21) extending out of the battery cell is less than or equal to 40 mm.

9. The battery according to claim 1, characterized in that, The connecting solder mark (60) is recessed into the surface of the tab (21), and the recess depth is 0.2mm-1mm.

10. The battery according to claim 1, characterized in that, It also includes a soldering pad, which is disposed on the tabs (21) of the same polarity of the two cells, and the connection solder mark (60) is located on the soldering pad.

11. The battery according to claim 10, characterized in that, The area of ​​the flux sheet is greater than or equal to the area of ​​the connection solder mark (60).

12. The battery according to claim 11, characterized in that, The ratio of the area of ​​the connecting solder mark (60) to the area of ​​the flux sheet is 0.7-0.

9.

13. The battery according to claim 10, characterized in that, The thickness of the flux sheet is 0.05mm-0.45mm.

14. The battery according to claim 1, characterized in that, Each of the tabs (21) has a pre-soldering stamp (50) that at least partially covers the end of the tab (21), and a connecting stamp (60) is either completely within the pre-soldering stamp (50) or extends beyond the pre-soldering stamp (50).

15. The battery according to claim 14, characterized in that, When the portion of the connecting solder stamp (60) extends beyond the pre-welded solder stamp (50), the area of ​​the connecting solder stamp (60) extending beyond the pre-welded solder stamp (50) is less than 2 / 3 of the total area of ​​the connecting solder stamp (60).

16. The battery according to claim 14, characterized in that, The ratio of the area of ​​the solder mark (60) connected to the area of ​​the pre-soldered solder mark (50) on a tab (21) is 0.2-0.

8.

17. The battery according to claim 14, characterized in that, Along the extension direction of the tab (21), the width of the pre-welded stamp (50) is 3mm-20mm.

18. The battery according to claim 14, characterized in that, The area of ​​the pre-welded solder mark (50) on each tab (21) is 80 mm². 2 -300mm 2 .

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