A battery device

Abstract

The application relates to the battery technical field and discloses a battery device, which comprises at least two single batteries, the single battery has a current output end comprising a pole, an insulating piece is arranged between the pole and the shell of the single battery, the height of the pole protruding from the insulating piece is e mm, a busbar comprises a main body area and a first connecting area, at least part of the first connecting area is in contact with the current output end and is fixed with the current output end through a first welding mark area arranged in the range of the first connecting area, the thickness of the main body area is d1 mm, the thickness of the first connecting area is d2 mm, d2 < d1, and the range of e / (d2 / d1) is 1.1-6. The thicknesses of the areas of the busbar are differentially arranged, the main body area is thickened to maintain the structural strength, the first connecting area is thinned, the current output end is more fully melted and connected when being welded with the thinner first welding mark area, the risk of false welding is reduced, and the overcurrent effect of the welding area is improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a battery device. Background Technology

[0002] In the battery pack structure, multiple individual cells need to be connected through a busbar. The busbar is usually formed on the positive or negative electrode of the individual cell by laser welding. However, the busbar needs to be connected to multiple current output terminals, which makes welding difficult and results in poor current carrying capacity in some welded areas. This causes the individual cells to have insufficient operating efficiency and increased heat generation during operation, which can easily lead to thermal runaway. Utility Model Content

[0003] In view of this, the purpose of this application is to provide a battery device that maintains the connection strength requirements of the busbar and reduces the risk of poor soldering between the busbar and the individual battery cells.

[0004] To achieve the above objectives, this application provides the following technical solution:

[0005] A battery device, comprising:

[0006] At least two individual cells, each cell having a current output terminal; the current output terminal includes a terminal post, and an insulating element is disposed between the terminal post and the casing of the individual cell, the terminal post protruding from the insulating element by a height of emm;

[0007] The bus includes a main body area and a first connection area. At least a portion of the first connection area is in contact with the current output terminal and is fixed to the current output terminal by a first solder area disposed within the range of the first connection area. The thickness of the main body area is d1mm, the thickness of the first connection area is d2mm, d2<d1, and e / (d2 / d1) ranges from 1.1 to 6.

[0008] As can be seen from the above technical solution, one aspect of this disclosure provides a battery device, which includes at least two individual batteries, and the at least two individual batteries are connected in a conductive manner through a busbar. Specifically, each individual battery has a current output terminal, which includes a terminal post, and an insulating member is disposed between the terminal post and the housing of the individual battery. The terminal post protrudes from the insulating member to connect with the busbar, and the height of the terminal post protruding from the insulating member is emm. The busbar achieves the function of current connection by connecting the current output terminals of different individual batteries. The busbar specifically includes a main body area and a first connection area, and the first solder area, which is welded and fixed to the current output terminal, is disposed within the range of the first connection area. It should be noted that the thickness d2mm of the first connection area is less than the thickness d1mm of the main body area, and the main body area has sufficient thickness to meet the requirements of the current output terminal. The design ensures sufficient connection strength for the busbar, preventing bending or breakage during battery use due to insufficient overall busbar rigidity. The thinned design of the first connection area facilitates melting of the first solder area when the current output terminal is welded to it, reducing welding difficulty and the risk of incomplete soldering. Correspondingly, the stable welding of the first solder area and the current output terminal provides good overcurrent capability, reducing resistance in the welding area during battery operation and minimizing heat generation, thus reducing the risk of thermal runaway. Simultaneously, the range of e / (d2 / d1) is 1.1-6 to avoid the risk of thermal deformation of insulation components and slag falling into the casing due to excessive size, while also preventing insufficient busbar strength due to excessive size, thereby improving the operational stability of the battery device. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the battery device structure provided in an embodiment of the present invention;

[0011] Figure 2 A schematic diagram of the assembly structure of the pole and the insulating component provided in an embodiment of this utility model;

[0012] Figure 3 This is a side view of the pole and insulating component provided in an embodiment of the present invention;

[0013] Figure 4 A schematic diagram of the assembly structure of a single busbar and a single battery cell provided in an embodiment of the present invention;

[0014] Figure 5 An exploded view of a busbar and a single battery cell provided in an embodiment of this utility model;

[0015] Figure 6 A schematic diagram of the connection structure between a single cell battery and the first connection area of ​​the busbar provided in an embodiment of the present invention;

[0016] Figure 7 A side view of the first connection area of ​​the busbar provided in an embodiment of the present invention;

[0017] Figure 8 An exploded view of the assembly of the first connection area and the pole post structure provided in an embodiment of this utility model;

[0018] Figure 9 This is a top view of the first connection area provided in an embodiment of the present invention;

[0019] Figure 10 This is a schematic diagram of the structure of the first connection area and the second connection area provided in an embodiment of the present utility model;

[0020] Figure 11 A schematic diagram of the assembly structure of the first connection area and the second connection area with two individual batteries, provided for an embodiment of the present invention;

[0021] Figure 12 A schematic diagram of the thickness of the first connection area and the second connection area provided in an embodiment of this utility model;

[0022] Figure 13 A schematic diagram of a busbar structure having multiple first connection areas and second connection areas is provided for an embodiment of the present invention.

[0023] in:

[0024] 10 - Single cell; 20 - Current output terminal; 210 - First output terminal; 220 - Second output terminal; 30 - Busbar; 310 - Main body area; 320 - First connection area; 3210 - First soldering area; 330 - Second connection area; 3310 - Second soldering area; 410 - Terminal post; 420 - Insulating component. Detailed Implementation

[0025] The core of this application is to disclose a battery device that maintains the connection strength requirements of the busbar and reduces the risk of poor soldering between the busbar and the individual battery cells.

[0026] To enable those skilled in the art to better understand the present application, embodiments of the present application will be described below with reference to the accompanying drawings. Furthermore, the embodiments shown below do not limit the scope of the utility model described in the claims. Additionally, the complete content of the structures represented in the following embodiments is not limited to those necessary for the solution of the utility model described in the claims.

[0027] like Figure 1 and Figure 4 As shown, one aspect of this disclosure provides a battery device including at least two individual cells 10 having current output terminals 20, and a bus 30 that is conductively connected to the current output terminals 20 of the at least two individual cells 10.

[0028] It should be noted that the single-cell battery 10 can store chemical energy and controllably convert it into electrical energy. In a recyclable battery, the active materials can be reactivated by charging after discharge for continued use. Typically, the single-cell battery 10 includes a casing and a cell disposed within the casing. Specifically, the casing is a component that provides a space to house the electrode assembly and other parts, isolating them from the external environment. The casing generally includes a body with an opening at at least one end and a receiving cavity. The opening of the casing can be closed by a cover plate to seal and isolate the internal environment of the single-cell battery from the external environment. The casing material includes, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and aluminum-plastic film.

[0029] Furthermore, in some embodiments, such as Figure 2 and Figure 3 As shown, the current output terminal 20 includes a terminal post 410, and an insulating element 420 is provided between the terminal post 410 and the casing of the single cell 10 to insulate the terminal post 410 and the casing. Specifically, the insulating element 420 is provided between the terminal post 410 and the upper surface of the battery casing (away from the cell), so that the terminal post 410 is insulated from the top surface of the battery casing. The insulating element 420 can be plastic, rubber or other insulating materials. The plastic can be one or a combination of polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC) and polyvinyl chloride (PVC), and the rubber can be one or a combination of fluororubber, nitrile rubber and isobutyl rubber.

[0030] It should be noted that the terminals are used to electrically connect the electrode assembly located inside the casing to external devices (adjacent batteries or other electrical equipment) located outside the casing. The battery can discharge to external devices through the cell output terminal (tab) and the external device output terminal (terminal assembly), and an external power source can charge the battery through the terminal assembly and the tab. The terminal assembly can be directly electrically connected to the cell tab or electrically connected to the tab through a metal adapter. The terminal assembly is made of metals including, but not limited to, copper, aluminum, aluminum alloy, and copper-aluminum alloy.

[0031] It should be noted that the current output terminals, namely the positive and negative terminals of the battery, are responsible for converting the chemical energy inside the battery into electrical energy and providing current to the external circuit. In cylindrical batteries, the positive terminal is usually a small cap structure with a raised top. Its base material can be aluminum or stainless steel. The positive electrode aluminum foil of the winding body is welded to the internal aluminum strip. During discharge, the current flows out from here, and during charging, the current flows in from here. The negative terminal is the cylindrical surface and bottom plane of the entire steel shell of the cylindrical battery. It can be made of nickel-plated deep-drawn steel shell. The negative electrode copper foil of the winding body is welded to the internal nickel strip. During discharge, the current flows back from here, and during charging, the current flows out from here.

[0032] Based on the above structure, the pole post 410 protrudes from the insulating member 420 so that while maintaining insulation with the housing, the pole post 410 can be connected to the busbar 30 through the protruding structure based on the insulating member 420. The height of the pole post 410 protruding from the insulating member 420 is emm.

[0033] Busbar 30 is used to connect the current output terminals 20 on different individual cells 10. In order to meet the requirements of connection stability and production efficiency, laser welding is currently used to melt and weld the overlapping area of ​​busbar 30 and current output terminal 20 to realize the assembly of busbar 30 and individual cell 10.

[0034] It should be noted that the bus 30 is electrically connected to the current output terminals 20 of at least two individual cells 10 to realize the series or parallel connection of multiple individual cells 10, and the bus 30 is made of metals such as copper, aluminum, tungsten, and manganese, or alloys such as copper-aluminum composite materials, which have good conductivity.

[0035] Correspondingly, such as Figure 4 and Figure 5As shown, the busbar 30 includes a main body region 310 and a first connection region 320. The first connection region 320 is disposed on one side of the main body region 310 and extends therefrom. The main body region 310 is used to form the main structure of the busbar 30 and is disposed in the gap area between adjacent single cells 10. The first connection region 320 is at least partially in contact with the current output terminal 20 to provide a position basis for welding. At the same time, the first connection region 320 is also provided with a first solder mark region 3210 in the overlapping area with the current output terminal 20. The first solder mark region 3210 is the welding setting area for laser welding. The laser welding process melts the first solder mark region 3210 to fix the first connection region 320 with the current output terminal 20, thereby completing the fixation and conductive connection between the busbar 30 and a current output terminal 20.

[0036] It should be noted that in the above structure, such as Figure 6 and Figure 7 As shown, the thickness of the main body area 310 is d1mm, and the thickness of the first connecting area 320 is d2mm, where d2 < d1. The main body area 310 is suspended between adjacent single cells 10 and needs to bear the functions of support and connection. If its thickness is too thin, the busbar 30 will not have sufficient rigidity. During the use of the battery device, there will be a greater risk of busbar 30 breaking due to shaking and impact, which will affect the operational stability of the battery device. As for the first connection area 320, it first maintains a close fit with the current output terminal 20 on the single cell 10 to obtain a certain support. Therefore, its structural strength requirement is lower than that of the main body area 310. At the same time, a first solder area 3210 is provided on the first connection area 320 to be welded and fixed to the current output terminal 20. Therefore, in this embodiment, the thickness d1mm of the main body area 310 is set to be less than the thickness d2mm of the first connection area 320. This is to meet the rigidity requirement of the busbar 30 through the thicker main body area 310. Meanwhile, for the first connection area 320 with lower rigidity requirement, its thickness is reduced to reduce the total weight of the battery device and reduce the difficulty of laser welding. During the welding process between the current output terminal 20 and the first solder area 3210, the first solder area 3210 can melt better to ensure the welding quality between the first connection area 320 and the current output terminal 20 and reduce the risk of poor welding.

[0037] It should also be noted that the current output terminal 20 and the first connection area 320, which maintain a stable connection, can ensure a good overcurrent effect between the single cell 10 and the bus 30. The single cell 10 can output sufficient operating efficiency and will not cause problems such as excessive resistance or high heat generation during operation due to unstable connection, thus reducing the risk of thermal runaway of the single cell 10.

[0038] Based on the above embodiments, the range of e / (d2 / d1) is 1.1-6, specifically 1.1, 2.1, 3.1, 4.1, 5.1, or 6. It should be noted that if e / (d2 / d1) is less than 1.1, during the welding process between the pole 410 and the busbar, there is a risk that the large welding heat may penetrate into the insulating component 420, causing the insulating component 420 to deform due to heat. During the welding process, welding slag may fall into the housing, resulting in insulation failure between the housing and the pole 410. If e / (d2 / d1) is greater than 6, the strength of the main body area of ​​the busbar is insufficient, which may lead to failure of the busbar due to insufficient strength during welding and use. Therefore, the range of e / (d2 / d1) is limited to 1.1-6 to meet the strength requirements of the busbar and reduce the risk of failure due to heat deformation of the insulating component 420.

[0039] Furthermore, in some embodiments of this disclosure, the ratio d2 / d1 of the thickness of the first connection area 320 to the thickness of the main body area 310 ranges from 0.5 to 0.9, specifically 0.5, 0.6, 0.7, 0.8, or 0.9. It should be noted that if d2 / d1 is less than 0.5, the overall strength of the busbar 30 will be insufficient. When the first connection area 320 meets the penetration welding requirements, the overall connection effect of the busbar 30 will be relatively weak, and there will be a greater risk of collision and breakage. If d2 / d1 is greater than 0.9, the thickness of the first connection area 320 and the main body area 310 will be similar, and the thinning effect of the first connection area 320 relative to the main body area 310 will be poor. There will still be a greater risk of insufficient welding, resulting in poor welding quality of the current output terminal 20 and affecting the overcurrent effect of the busbar 30 and the current output terminal 20. Therefore, in this embodiment, the range of d2 / d1 is limited to 0.5-0.9, so as to meet the overall strength requirements of the busbar 30 while ensuring that the thinning effect of the first connection area 320 can meet the requirements for the smooth melting connection of the current output terminal 20 at the position of the first solder area 3210.

[0040] In some embodiments of this disclosure, along the thickness direction of the busbar 30, the first connection area 320 is protruding from one side of the main body area 310. It should be noted that the protruding structure creates a clear layered structure between the first connection area 320 and the main body area 310. That is, one or both of the upper and lower surfaces of the first connection area 320 in the thickness direction are misaligned with the surface of the main body area 310 in the thickness direction. This allows for clear identification of the boundary position of the first connection area 320 during the stamping process of the busbar 30 to form the first connection area 320, facilitating the identification of the stamping area. At the same time, during the battery assembly process, the protruding structure of the first connection area 320 allows the assembler to clearly identify the position of the first connection area 320 and accurately align the first connection area 320 with the current output terminal 20, thereby reducing the assembly difficulty of the battery device.

[0041] Based on the above embodiments, in some embodiments, such as Figure 6 and Figure 7 As shown, along the thickness direction of the busbar 30, i.e., along the axial direction of the cylindrical single cell 10, the height difference L1mm between the surfaces of the first connecting area 320 and the main body area 310 on the side away from the single cell 10 ranges from 0.8mm to 2.5mm, specifically 0.8mm, 1.2mm, 1.4mm, 1.9mm, or 2.5mm. It should be noted that the surface height difference L1mm between the first connecting area 320 and the main body area 310 represents the protrusion height of the first connecting area 320. If L1mm is less than 0.8mm, the height difference between the first connecting area 320 and the main body area 310 is too small, which will affect the thickness of the first connecting area 320 during the stamping and thinning process. The lack of a distinct layered structure presents significant processing challenges. Furthermore, if L1mm is greater than 2.5mm, the misalignment between the first connection area 320 and the main body area 310 becomes more pronounced. For the thinner first connection area 320, a significant deflection between it and the main body area 310 would result in a weak connection structure, leading to a reduction in the overall strength of the busbar 30. Therefore, in this embodiment, the surface height difference L1mm between the first connection area 320 and the main body area 310 on the side away from the single cell 10 is limited to 0.8mm-2.5mm to balance the ease of processing the first connection area 320 with the overall structural strength of the busbar 30, thus ensuring effective conduction connection of the busbar 30 to the current output terminal 20.

[0042] In other embodiments of this disclosure, along the thickness direction of the busbar 30, the height difference L2mm between the first connection area 320 and the surface of the main body area 310 facing the single cell 10 ranges from 1mm to 3.5mm, specifically 1mm, 1.7mm, 2.4mm, 3.1mm, or 3.5mm. It should also be noted that if L2mm is less than 1mm, the first connection area 320 will also have the problem of difficult processing during the thinning operation. If L2mm is greater than 3.5mm, the first connection area 320 will be thinner and have a large deflection, which will lead to a weak structure in the connection area and reduce the overall strength of the busbar 30. Therefore, the range of the height difference L2mm between the surface of the first connection area 320 and the surface of the main body area 310 facing the single cell 10 is limited to 1mm-3.5mm to balance the processing difficulty of the first connection area 320 and the structural strength requirements of the busbar 30.

[0043] Based on the above structure, when the first connection area 320 is connected to the current output terminal 20 with a raised terminal structure on one end face of the single cell 10, preferably the first connection area 320 protrudes from the main body area 310 in a direction away from the single cell 10, so that the first connection area 320 can be raised, allowing the main body area 310 on the busbar 30 to be set lower than the terminal, and the height change is only achieved in the first connection area 320, thereby reducing the overall center of gravity height of the busbar 30 and improving its structural stability. Specifically, the center line of the first connection area 320 in its thickness direction is set further away from the single cell 10 than the center line of the main body area 310 in its thickness direction, so that the first connection area 320 forms a staggered protrusion structure based on the main body area 310, which is adapted to the current output terminal 20 with the raised terminal structure.

[0044] It should be further explained that the first connection area 320, which protrudes from the main body region 310 towards the side away from the single cell 10, can form a misalignment to adapt to the current output terminal 20 of the protruding electrode structure, and as... Figure 8As shown, in some embodiments, the height of the electrode post is d3mm, and L2 < d3. Specifically, L2mm is the height difference between the surface of the first connection area 320 and the main body area 310 facing the single cell 10. If L2 > d3, there will be a problem that the height difference between the first connection area 320 and the main body area 310 is too large. After the first connection area 320 is attached to the top of the electrode post, the main body area 310 may interfere with the end face of the single cell 10 on the side where the electrode post is located due to the excessive height difference, resulting in a short circuit risk, or the first connection area 320 may not be able to attach to the top plane of the current output terminal 20, resulting in a risk of poor soldering during the welding process. However, L2 < d3 can make the height difference between the surface of the first connection area 320 and the main body area 310 less than the height of the electrode post. When the first connection area 320 is attached to the top of the current output terminal 20 of the protruding electrode post structure, the main body area 310 can still maintain a certain gap with the end face of the single cell 10 on the side where the electrode post is located, thus satisfying the smooth assembly of the busbar 30 and the current output terminal 20.

[0045] It should be noted that in some embodiments, d3mm ranges from 1.2mm to 4.5mm, and can specifically be 1.2mm, 2mm, 2.8mm, 3.6mm, 4mm or 4.5mm.

[0046] In some other embodiments of this disclosure, the current output terminal 20 is the housing structure of the single battery 10. Based on this, the side of the first connection area 320 facing the single battery 10 and the side of the main body area 310 facing the single battery 10 can be flush to avoid the side of the first connection area 320 facing the single battery 10 being farther away from the single battery 10 than the side of the main body area 310 facing the single battery 10. When the main body area 310 is attached to the housing of the single battery 10, it interferes with the single battery 10. At the same time, the first connection area 320 has a thickness difference with the main body area 310 by the side away from the single battery 10, thus ensuring that the thickness reduction requirement of the first connection area 320 relative to the main body area 310 is met.

[0047] It should also be noted that the side of the first connection area 320 facing the single battery 10 can also be set as a protruding structure facing the single battery 10 based on the side of the main body area 310 facing the single battery 10. The protruding structure can indicate the assembly position for the assembler, and when the first connection area 320 is attached to the shell of the single battery 10, the main body area 310 and the shell of the single battery 10 maintain a certain distance, thereby ensuring the precise docking of the busbar 30 and the single battery 10 and reducing the assembly difficulty.

[0048] Furthermore, in some embodiments of this disclosure, the thickness of the main body region 310, d1mm, ranges from 0.5mm to 4mm, specifically 0.5mm, 0.8mm, 1.2mm, 1.8mm, 2.8mm, 3.5mm, or 4mm. The thickness limitation of the main body region 310 is to meet its overcurrent requirements while avoiding the problem of insufficient rigidity caused by excessive thickness, and also to avoid the increase in weight and material cost of the battery device caused by excessive thickness of the main body region 310. The thickness d2mm of the first connecting area 320 ranges from 0.3mm to 2.2mm, specifically 0.3mm, 0.8mm, 1.4mm, 1.8mm, or 2.2mm. It should be noted that the thickness of the first connecting area 320 needs to be thinner than the thickness of the main body area 310. Based on this, the range of the thickness d2mm of the first connecting area 320 is limited to 0.3mm-2.2mm, so that the first connecting area 320 will not be too thick, which would make welding difficult and prevent the first solder area 3210 from completely melting, nor will it be too thin, which would easily cause breakage failure.

[0049] Furthermore, in the battery device provided in the embodiments of this disclosure, such as Figure 7 As shown, along the thickness direction of the busbar 30, the projected area of ​​the first connection region 320 is S1mm. 2 The projected area of ​​the first solder area 3210 is S2mm. 2 Furthermore, the range of S2 / S1 is 0.06-0.4, specifically 0.06, 0.15, 0.22, 0.35, or 0.4. It should be noted that the first solder area 3210 is a welding area located within the first connection area 320. If S2 / S1 is less than 0.06, the proportion of the first solder area 3210 on the first connection area 320 is too small, resulting in poor welding quality between the busbar 30 and the current output terminal 20, which is prone to welding failure. If S2 / S1 is greater than 0.4, there will be a large welding area after the first connection area 320 and the current output terminal 20 are connected. This not only increases the welding time and extends the production cycle, but the excessively large welding area will also reduce the remaining connection structure between the first connection area 320 and the main body area 310, resulting in a decrease in the overall structural strength of the busbar 30 and a risk of conductive connection failure. Therefore, in this embodiment, the range of S2 / S1 is limited to 0.06-0.4, so as to meet the welding strength requirements of bus 30 and current output terminal 20, while avoiding the welding area being too large and affecting the strength of the main body area 310 and the first connection area 320 of bus 30 itself.

[0050] Based on the above embodiment, the projected area of ​​the first connection area 320 is S1mm. 2 The range is 30mm 2 -100mm 2Specifically, it can be 30mm 2 50mm 2 70mm 2 90mm 2 Or 100mm 2 This is to avoid the problem that the busbar 30 and the current output terminal 20 have insufficient contact area and the overcurrent area cannot meet the requirements due to the small area of ​​the first connection area 320; at the same time, it ensures that the area of ​​the first connection area 320 is not too large and will occupy the structural space in the battery device, or interfere with other densely arranged single cells 10, while reducing material costs.

[0051] The projected area of ​​the first solder area 3210 is S2mm. 2 Its range is 5mm 2 -20mm 2 Specifically, it can be 5mm. 2 10mm 2 15mm 2 Or 20mm 2 So that the area of ​​the first solder area 3210 is greater than 5mm². 2 Sufficient welding area is provided to ensure that the connection between busbar 30 and current output terminal 20 meets the strength and overcurrent requirements; at the same time, the area of ​​the first solder area 3210 will not exceed 20mm². 2 This is to avoid increasing production time due to an excessively large welding area, and to maintain the structural strength requirements of the first connection area 320 without causing excessive damage to the structure of the first connection area 320.

[0052] Furthermore, in the battery device provided in the embodiments of this disclosure, such as Figure 9 and Figure 10 As shown, the first connection area 320 and the first solder area 3210 have the same configuration. Here, "same configuration" means that the first connection area 320 and the first solder area 3210 have similar structures. For example, in some embodiments, the first connection area 320 has a circular ring structure, and correspondingly, the first solder area 3210 has a scaled-down circular ring structure. Preferably, the first connection area 320 and the first solder area 3210 are concentrically arranged. In other embodiments, the first connection area 320 has a partial circular ring, i.e., an arc-shaped structure, and correspondingly, the first solder area 3210 also has an arc-shaped structure. Also preferably, the first connection area 320 and the first solder area 3210 are concentrically arranged.

[0053] It should be noted that the first connection area 320 and the first solder area 3210 with the same configuration can ensure that the weld after welding is evenly applied to each position of the first connection area 320, thus ensuring the connection effect between each area of ​​the first connection area 320 and the current output terminal 20, and maintaining a stable conductive connection.

[0054] In order to further optimize the above technical solution, in some embodiments of this disclosure, such as Figure 9 As shown, along the radial direction of the single cell 10, the distance L3mm between the first solder area 3210 and the first connection area 320 ranges from 1.5mm to 6mm, specifically 1.5mm, 2.5mm, 3.5mm, 4mm, 5.5mm, or 6mm. It should be noted that having identical configurations for the first connection area 320 and the first solder area 3210 ensures consistent spacing between them at all locations. This results in a more uniform structural impact of the first solder area 3210 on the first connection area 320, and a more uniform fixing effect of the weld seam on the first connection area 320. By reducing the distance L3mm between the first solder area 3210 and the first connection area 320 to a range of 1.5mm-6mm, it is possible to avoid the risk of the welding area being too close to the edge of the first connection area 320 due to the small distance between them, which could lead to the risk of the edge of the first connection area 320 being damaged by soldering during the welding process. At the same time, it is also possible to avoid the problem of the welding area being too close to the center of the first connection area 320 due to the large distance between them, which could lead to the edge of the first connection area 320 not being able to stably and effectively fit the current output terminal 20. This ensures the stable connection function of the first solder area 3210 for the first connection area 320 and the current output terminal 20.

[0055] Furthermore, in some embodiments of this disclosure, such as Figure 11 As shown, the busbar 30 has connection areas with different structures for connection to current output terminals 20 with different structures on the individual battery cells 10. Specifically, the busbar 30 also includes a second connection area 330, and similarly, a second solder area 3310 is provided within the range of the second connection area 330. Correspondingly, the current output terminal 20 includes a first output terminal 210 and a second output terminal 220.

[0056] In some embodiments, the first output terminal 210 is the positive output terminal of the single cell 10, which adopts a raised terminal structure, while the second output terminal 220 is the negative output terminal of the single cell 10, which is the battery casing structure. In order to realize the convergence of different single cells 10, the first output terminal 210 is welded and fixed to the first solder area 3210, and the second output terminal 220 is welded and fixed to the second solder area 3310 to meet the connection requirements.

[0057] Based on the above embodiments, such as Figure 12As shown, the thickness of the second connection region 330 is d4mm, and the range of d2 / d4 is 0.8-1.2, specifically 0.8, 0.9, 1.0, 1.1 or 1.2. It should be noted that d2mm is the thickness of the first connection region 320, and d2 / d4 needs to be greater than 0.8 and less than 1.2 so that the thickness difference between the second connection region 330 and the first connection region 320 is not too large. This avoids a large difference in current carrying capacity between the two connection regions due to a large thickness difference, resulting in a large difference in heat generation at different positions on the busbar 30. This would lead to a large risk of thermal runaway due to heat concentration. Preferably, d2 / d4 is close to or equal to 1 so that the thickness of the second connection region 330 and the first connection region 320 are similar, and they have similar current carrying capacity, reducing the risk of heat concentration in some areas of the battery device.

[0058] Furthermore, in the single cell 10, the melting point of the first output terminal 210 is k1℃, and the melting point of the second output terminal 220 is k2℃, where k1 < k2. It should be noted that the first output terminal 210 is the positive electrode of the single cell 10, and the material of the current output terminal 20 of the positive electrode is usually aluminum or aluminum alloy, which has a low melting point of 500℃-700℃. The second output terminal 220 is the negative electrode of the single cell 10, and the material of the current output terminal 20 of the negative electrode is usually copper or copper alloy, which has a high melting point of 900℃-1100℃. Correspondingly, the thickness d2mm of the first connection area 320 is greater than the thickness d4mm of the second connection area 330, so that the thickness of the second connection area 330 corresponding to the negative electrode second output terminal 220 is thinner. When the laser welding temperature is constant, the thinner second connection area 330 is easier to melt and can be welded and fixed to the current output terminal 20 of the negative electrode to maintain the welding quality.

[0059] Furthermore, based on the above embodiments, the difference between the thickness d2mm of the first connection area 320 and the thickness d4mm of the second connection area 330, d2-d4, ranges from 0.1mm to 0.3mm, specifically 0.1mm, 0.2mm, or 0.3mm. It should be noted that, as in the aforementioned embodiments, the differentiated thickness setting of the first connection area 320 and the second connection area 330 is based on achieving stable connection for current output terminals 20 made of different materials. If d2-d4 is less than 0.1mm, then the thickness difference between the first connection area 320 and the second connection area 330 is excessive. The small diameter makes it difficult to maintain welding quality for different materials, especially the negative electrode; while if d2-d4 is greater than 0.3mm, the first connection area 320 and the second connection area 330 will have different current carrying capacities due to the thickness difference. The large difference in current carrying capacity in each area of ​​the busbar 30 may lead to localized overheating and excessive temperature, which will affect the temperature uniformity of each area in the battery device. Therefore, the range of d2-d4 is limited to 0.1mm-0.3mm to balance the welding quality requirements of the first connection area 320 and the second connection area 330 as well as the uniformity of current carrying capacity.

[0060] It should be noted that in some embodiments, d4mm ranges from 0.2mm to 2mm, specifically 0.2mm, 0.8mm, 1.2mm, 1.6mm or 2mm.

[0061] Furthermore, such as Figure 13 As shown, for a battery device with multiple individual cells 10 arranged in an internal array, in some embodiments, the first connection area 320 and the second connection area 330 are respectively arranged on both sides of the busbar 30 along its length direction, the main body area 310 of the busbar 30 is arranged between two individual cells 10, and the first connection area 320 and the second connection area 330 located on both sides are welded and fixed to the current output terminal 20 on the two individual cells 10, so that the components inside the battery device are arranged more evenly and the structural integration is improved.

[0062] Furthermore, for a battery device having multiple individual cells 10, multiple busbars 30 can be provided to connect multiple individual cells 10. Preferably, each busbar 30 includes at least one first connection area 320 to weld multiple connection positions as needed. At the same time, the number of first connection areas 320 and second connection areas 330 in a single busbar 30 is equal, so that the busbar 30 forms a symmetrical structure. The number of connection points driven by the first connection area 320 and the second connection area 330 is the same, so that the overcurrent load and heat generation on both sides of the single busbar 30 are similar, thereby improving the operational stability of each area on the busbar 30.

[0063] Furthermore, in some embodiments, the range of emm is 1mm-3mm, specifically 1mm, 1.5mm, 2mm, 2.5mm or 3mm. It should be noted that if emm is less than 1mm, it will affect the insulation performance of the insulating component 420 to the terminal post 410 and the casing, while if emm is greater than 1mm, it will cause the terminal post to occupy more of the height space of the single cell, thus affecting the energy density of the single cell.

[0064] The terms "first," "second," "left side," and "right side," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units may not be defined in the listed steps or units, but may include steps or units not listed.

[0065] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery device, characterized in that, include: At least two individual cells (10), each individual cell (10) having a current output terminal (20); the current output terminal (20) includes a terminal (410), an insulating element (420) is provided between the terminal (410) and the housing of the individual cell (10), and the terminal (410) protrudes from the insulating element (420) by a height of emm; Bus (30) includes a main body area (310) and a first connection area (320). At least a portion of the first connection area (320) contacts the current output terminal (20) and is fixed to the current output terminal (20) by a first solder area (3210) disposed within the range of the first connection area (320). The thickness of the main body area (310) is d1mm, the thickness of the first connection area (320) is d2mm, and d2 < d1, and the range of e / (d2 / d1) is 1.1-6.

2. The battery device as claimed in claim 1, characterized in that, The ratio of the thickness of the first connecting region (320) to the thickness of the main body region (310), d2 / d1, ranges from 0.5 to 0.

9.

3. The battery device as claimed in claim 1, characterized in that, Along the thickness direction of the busbar (30), the first connection area (320) is provided to protrude from one side of the main body area (310).

4. The battery device as claimed in claim 3, characterized in that, Along the thickness direction of the busbar (30), the height difference L1mm between the first connection area (320) and the main body area (310) on the side of the single cell (10) away from the main body area (310) ranges from 0.8mm to 2.5mm.

5. The battery device as claimed in claim 3, characterized in that, Along the thickness direction of the busbar (30), the height difference L2mm between the first connection area (320) and the main body area (310) on the side of the single cell (10) ranges from 1mm to 3.5mm.

6. The battery device as claimed in claim 5, characterized in that, The current output terminal (20) is a pole post, and the center line of the first connection area (320) in its thickness direction is set away from the single cell (10) compared to the center line of the main body area (310) in its thickness direction.

7. The battery device as claimed in claim 6, characterized in that, The height of the pole is d3mm, and L2 < d3.

8. The battery device as claimed in claim 5, characterized in that, The current output terminal (20) is a housing; the first connection area (320) is flush with or protrudes from the main body area (310) facing the single battery (10).

9. The battery device as claimed in claim 1, characterized in that, The range of d1mm is 0.5mm-4mm, and the range of d2mm is 0.3mm-2.2mm.

10. The battery device as claimed in claim 1, characterized in that, Along the thickness direction of the busbar (30), the projected area of ​​the first connection area (320) is S1mm. 2 The projected area of ​​the first solder area (3210) is S2mm. 2 Therefore, the range of S2 / S1 is 0.06-0.

4.

11. The battery device as claimed in claim 10, characterized in that, The S1mm 2 The range is 30mm 2 -100mm 2 The S2mm 2 The range is 5mm 2 -20mm 2 .

12. The battery device as claimed in claim 1, characterized in that, The first connection area (320) has the same configuration as the first solder area (3210).

13. The battery device as claimed in claim 12, characterized in that, Along the radial direction of the single cell (10), the distance L3mm between the edge of the first solder area (3210) and the edge of the first connection area (320) ranges from 1.5mm to 6mm.

14. The battery device as claimed in claim 12, characterized in that, The first solder area (3210) is a ring or arc-shaped structure.

15. The battery device as claimed in claim 1, characterized in that, The bus (30) further includes a second connection area (330) and a second solder area (3310) disposed within the range of the second connection area (330); the current output terminal (20) includes a first output terminal (210) and a second output terminal (220), the first output terminal (210) and the second output terminal (220) being fixed to the first solder area (3210) and the second solder area (3310) respectively.

16. The battery device as claimed in claim 15, characterized in that, The thickness of the second connection area (330) is d4mm, and the range of d2 / d4 is 0.8-1.

2.

17. The battery device as claimed in claim 15, characterized in that, The melting point of the first output terminal (210) is k1℃, the melting point of the second output terminal (220) is k2℃, k1 < k2; the thickness of the second connection area (330) is d4mm, d2 > d4.

18. The battery device as claimed in claim 17, characterized in that, The range of d2-d4 is 0.1mm-0.3mm.

19. The battery device as claimed in claim 15, characterized in that, The first connection area (320) and the second connection area (330) are respectively disposed on both sides of the busbar (30) along its length direction.

20. The battery device as claimed in claim 15, characterized in that, Each busbar (30) includes at least one first connection area (320), and the number of first connection areas (320) and second connection areas (330) in a single busbar (30) is equal.

21. The battery device as claimed in claim 1, characterized in that, The range of emm is 1mm-3mm.

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