Prefabricated battery, connecting structure, planar battery pack and preparation method of planar battery pack

Abstract

The invention discloses a prefabricated battery which comprises a battery pole of a single battery and an electric conductor, an overlapping area is arranged between the battery pole and the electric conductor, and a first fastening belt area and a first conductive adhesive spot area are arranged in the overlapping area. The structure connection characteristic of hot welding connection and the electric flux characteristic of cold welding connection are brought into full play, mutual interference of the hot welding connection and the cold welding connection is avoided, the electric flux of the product is advanced in the industry, meanwhile, the connection stability is high under strong vibration, and the production efficiency is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of new energy technology, and in particular relates to a prefabricated battery, a connection structure, a planar battery pack and its preparation method. Background Technology

[0002] As the capacity of individual battery cells increases, especially for power batteries, the maximum current flow requirement at the electrical connection between the corresponding surfaces of the two conductors between the battery terminals and the busbar also increases, while high reliability of electrical and structural connections is also required.

[0003] Existing connection technologies mainly include deep penetration hot welding (including spot welding and laser welding), submerged hot welding, and cold welding to achieve reliable connections between battery terminals and busbars. While deep penetration hot welding offers high connection strength, the weld spots formed by localized metal fusion are typically small with limited cross-sectional area. Therefore, the current throughput of the original 2 or 4 weld spots in small-capacity batteries is insufficient to meet the high current throughput requirements of high-rate charging and discharging of large-capacity cells, necessitating the synthesis and splicing of numerous weld spots into a larger weld spot. However, spot welding, a current-penetrating fusion process, is greatly affected by various factors, which can easily lead to abnormalities in connection strength and contact resistance, such as false welds or spurious welds. While laser welding, a point-to-point energy-concentrating fusion process, ensures connection reliability, the consistency of fusion quality can only be guaranteed at the same distance when connecting groups of batteries. Due to the height tolerance of multiple cells, the yield of single-sided laser welding of battery packs is significantly higher than that of laser welding at both ends. On the other hand, metal welding usually requires a single welding machine to perform point-by-point welding, resulting in low production efficiency and long time consumption for multi-point welding. Therefore, the top single-pole post electrical connection process usually becomes the bottleneck point in the entire production process.

[0004] For submerged hot welding and cold welding technologies, although the conductive adhesive patch of cold welding filler is larger and the electrical flux is greater under a certain pressing pressure, which can meet the high electrical flux requirements, the peel force of adhesive bonding and shallow melt bonding is weak, and the connection stability of a single connection point is insufficient. To maintain the reliability of electrical connection points, the shallow melt hot welding process usually adopts the method of strengthening the structure between batteries (such as full glue injection between batteries) to reduce the stress on the electrical connection points under strong vibration, thereby enhancing the reliability of the electrical connection points. However, the cost of external structural reinforcement is high, the weight is heavy (affecting the weight energy density index of the assembly), and the production convenience is not enough, which urgently needs to be improved. The cold welding process usually adopts the battery pack cluster extrusion structure. By increasing the friction and maintaining the stability of the tight connection, it reduces the stress on the weak electrical connection points under strong vibration, thereby enhancing the reliability of the electrical connection points. However, under extremely strong vibration, there will still be a slight impact. Therefore, how to further enhance the reliability of electrical connection points with low weight increase and convenient operation while maintaining low-voltage connections is one of the key technical challenges in the transition from ordinary electrical connections to precision electrical connections in group technology.

[0005] In summary, there is currently no battery terminal and conductor connection structure that simultaneously satisfies both electrical connection flux and structural connection strength. Summary of the Invention

[0006] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a prefabricated battery, connection structure, planar battery pack and its preparation method that can simultaneously satisfy the electrical connection flux and structural connection strength.

[0007] The objective of this invention is achieved through the following technical solution: a prefabricated battery, comprising a single cell, the single cell including a battery body and battery terminals, the battery terminals located within the top view contour of the battery body protruding and connected to the top of the battery body, and having a first surface away from the battery body; a conductor for longitudinally stacking and connecting with the battery terminals, the conductor having a second surface near the battery terminals, the second surface having at least a partially overlapping area with the first surface of the battery terminals, wherein at least one end of the conductor located outside the overlapping area extends outward toward the side of the top view contour of the battery body for electrical connection with other single cells or prefabricated batteries; a first fastening band area, including at least three and no more than ten spaced... The hot-welded weld spots are arranged in a triangular or polygonal pattern by connecting lines in the overlapping area. These hot-welded weld spots together form a secondary first electrical connection channel between the first and second surfaces. The closed-loop connecting lines between the centers of the multiple hot-welded weld spots form an enclosed area, which is used to keep the periphery and / or the area inside the enclosed area between the first and second surfaces abutting and / or connected. A first conductive adhesive spot area is filled in the enclosed area and includes a first conductive adhesive. At least a portion of the first conductive adhesive spot area is connected to the first and second surfaces by the first conductive adhesive filled in the gaps between the non-direct contact points between the first and second surfaces and then abutted after curing. The other portion is abutted by the direct contact points between the first and second surfaces, together forming a main first electrical connection channel.

[0008] The prefabricated battery of the present invention utilizes a combination of hot welding and cold welding processes to apply at least three and no more than ten hot welding spots in the overlapping area. At least three hot welding spots form a stable planar connection, and the number of hot welding spots is limited to no more than ten to avoid excessive interaction between hot welding spots, which could lead to a loss of connection strength. Each hot welding spot forms a strong connection point between the battery terminal and the conductor. When all hot welding spots form multiple strong connection points, they form a tight band area with a coverage area. Points without hot welding spots in the tight band area are also tightened by the surrounding hot welding spots, thereby forming an enclosure in the tight band area. The space within the fastening zone is filled with conductive adhesive. This creates a balanced connection system with strong peripheral connections and auxiliary central connections. Furthermore, the strong peripheral connection of the fastening zone ensures a negative tolerance between the battery terminals and conductors within the space due to the reaction force of the conductive adhesive. This results in a more stable contact between the conductive adhesive and the battery terminals and conductors, guaranteeing the electrical flux and stability at the conductive adhesive location. Ultimately, this forms a balanced connection system where the conductive adhesive provides the primary electrical connection and provides auxiliary structural stability, while the fastening zone formed by the deep-melt hot-weld weld provides the primary structural stability and auxiliary electrical connection. Simultaneously, using this connection structure in prefabricated batteries allows for simultaneous control of the pressing height of multiple conductors during the battery assembly process, ensuring consistent pressing distances between each conductor and battery terminal. This guarantees consistent and stable electrical flux across all battery terminals, significantly improving production efficiency and effectiveness.

[0009] Furthermore, in the prefabricated battery of the present invention, the first surface and the second surface within the overlapping area are substantially matched and bonded together.

[0010] Furthermore, in the prefabricated battery of the present invention, the battery terminals and the conductor are metal conductors with similar thickness and similar melting points, so as to be suitable for achieving a reliable structural connection between the two by using a deep-penetration hot welding connection process.

[0011] Furthermore, in the prefabricated battery of the present invention, the battery terminals and the conductor are metal conductors of the same thickness and material.

[0012] Furthermore, in the prefabricated battery of the present invention, the hot weld spot is obtained by a deep penetration hot welding connection process.

[0013] Furthermore, the prefabricated battery of the present invention also includes at least one second fastening band area disposed around the outer periphery of the first fastening band area. Each second fastening band area includes at least three and no more than ten hot-welding spots formed by connecting lines spaced apart therein, which are used to press and / or connect the first and second surfaces in the second conductive adhesive spot area formed between each second fastening band area and the first fastening band area, or between two second fastening band areas, and to form a secondary second electrical connection channel. At least a portion of the second conductive adhesive spot area is filled with second conductive adhesive to form a primary second electrical connection channel.

[0014] Furthermore, in the prefabricated battery of the present invention, each of the hot-welded weld spots is located within the corresponding fastening zone, and there is a gap between the outer periphery and the two side boundaries of the corresponding fastening zone.

[0015] Furthermore, in the prefabricated battery of the present invention, there is an angular difference between the triangle or polygon formed by the connecting lines of the hot weld spots in each layer of the fastening zone and the triangle or polygon formed by the connecting lines of the hot weld spots in adjacent fastening zones.

[0016] Furthermore, in the prefabricated battery of the present invention, the hot-welded weld spots in the fastening zone of each layer are arranged in a plurality of straight lines.

[0017] Furthermore, in the prefabricated battery of the present invention, there is a gap between the hot-welded weld spot and the conductive adhesive.

[0018] Furthermore, in the prefabricated battery of the present invention, the conductive adhesive is a cold solder adhesive that can be cured at room temperature.

[0019] Furthermore, the prefabricated battery of the present invention also includes at least one sealed zone area, which surrounds the outer periphery of the outermost fastening zone area. The sealed zone area is fully provided with adhesive and is closed at both ends. The adhesive is bonded to the first surface and the second surface respectively, so that the adhesive forms a sealed cavity after curing.

[0020] Furthermore, in the prefabricated battery of the present invention, the sealed zone is spaced apart from each of the hot-welding spots.

[0021] Furthermore, in the prefabricated battery of the present invention, the adhesive is a structural adhesive.

[0022] Furthermore, in the prefabricated battery of the present invention, the structural adhesive is a pressure-cured structural adhesive.

[0023] Furthermore, in the prefabricated battery of the present invention, the structural adhesive is a fast-drying structural adhesive.

[0024] Furthermore, in the prefabricated battery of the present invention, the structural adhesive is a structural adhesive that is not easily swollen or melted.

[0025] Furthermore, in the prefabricated battery of the present invention, the adhesive is a conductive adhesive, suitable for forming a primary third electrical connection channel.

[0026] Furthermore, in the prefabricated battery of the present invention, a pad is provided in the conductive adhesive patch area between the first surface and the second surface. The pad includes a conductive post with longitudinal electrical connection. The pad has an upper surface and a lower surface. The conductive post includes a conductor connection end located on the upper surface and the lower surface. At least the conductor connection end is respectively pressed against the first surface and the second surface to form a first pressing point and a second pressing point.

[0027] Furthermore, in the prefabricated battery of the present invention, at least the conductor connection end and the first surface are electrically connected by the conductive adhesive.

[0028] Furthermore, in the prefabricated battery of the present invention, the pad and the conductor are an integrated structure.

[0029] Furthermore, in the prefabricated battery of the present invention, the conductive post and the conductive body are an integrated structure.

[0030] Furthermore, in the prefabricated battery of the present invention, the conductive pillar is an elastic conductive mass.

[0031] Furthermore, in the prefabricated battery of the present invention, the conductive mass is a clump-shaped conductor formed from a metal cutting strip, a conductor filament, or a filament braid.

[0032] Furthermore, in the prefabricated battery of the present invention, the conductive group is a short filament of a bulk metal or non-metal conductor, which is filled with conductive adhesive and cured to form a conductive column.

[0033] Furthermore, in the prefabricated battery of the present invention, the conductive post is a folded metal sheet.

[0034] Furthermore, in the prefabricated battery of the present invention, the conductive column is a conductive package containing conductive powder. After the package is broken by the first and second surfaces, the conductive powder forms an abutment electrical connection with the first and second surfaces respectively.

[0035] Furthermore, in the prefabricated battery of the present invention, the conductive adhesive is coated around the outer periphery of the conductive post and sealed around the outer periphery of the conductive post after compression.

[0036] Furthermore, in the prefabricated battery of the present invention, the hot-welded weld spots located in the same fastening zone are on the same circumference.

[0037] Furthermore, in the prefabricated battery of the present invention, the hot-welded weld spots within the same fastening zone are evenly and symmetrically distributed.

[0038] Furthermore, in the prefabricated battery of the present invention, the hot-welded weld spots within the same fastening zone are distributed in an equilateral triangle pattern.

[0039] Furthermore, in the prefabricated battery of the present invention, the same second conductive spot area is annular, forming an inner circumference and an outer circumference.

[0040] Furthermore, in the prefabricated battery of the present invention, the inner circumference and the outer circumference are concentric circles.

[0041] Furthermore, in the prefabricated battery of the present invention, all the circumferences are concentric circles.

[0042] Furthermore, in the prefabricated battery of the present invention, the same second conductive spot area is annular, forming an inner circumference and an outer circumference, and all of the circumferences, inner circumferences, and outer circumferences are concentric circles.

[0043] Furthermore, in the prefabricated battery of the present invention, the sealed zone is annular, forming an inner circle Thursday and an outer circle Friday.

[0044] Furthermore, in the prefabricated battery of the present invention, all the circumferences are concentric circles, and the same second conductive spot area is annular, forming an inner circumference and an outer circumference. All the circumferences, including the circumferences, inner circumferences, outer circumferences, inner circumferences, and outer circumferences, are concentric circles.

[0045] The objective of this invention is achieved through the following technical solution: a connection structure comprising: a first busbar having a first surface; a second busbar for longitudinally stacking with the first busbar, the second busbar having a second surface adjacent to the first busbar, the second surface and the first surface of the first busbar having at least a partially overlapping area; and a first fastening band area comprising at least three and no more than ten hot-welding spots arranged at intervals within the overlapping area, the hot-welding spots collectively forming a secondary first electrical connection between the first surface and the second surface. The channel, a closed loop connecting the centers of multiple hot-welded weld spots forms an enclosed area, used to keep at least the periphery and / or connection of the enclosed area between the first surface and the second surface; a first conductive adhesive spot area, filled in the enclosed area, includes a first conductive adhesive, at least a portion of the first conductive adhesive spot area is connected to the first surface and the second surface respectively by the first conductive adhesive filled in the non-direct contact gap between the first surface and the second surface and then abutted after curing, the other portion is abutted by the direct contact point between the first surface and the second surface, together forming a main first electrical connection channel.

[0046] The objective of this invention is achieved through the following technical solution: a planar battery pack comprising a plurality of prefabricated batteries arranged in a planar manner, each prefabricated battery comprising: a single cell, the single cell comprising a battery body and a battery terminal, the battery terminal located within the top view contour of the battery body protruding and connected to the top of the battery body, and having a first surface away from the battery body; a conductor for longitudinally stacking and connecting with the battery terminal, the conductor having a second surface near the battery terminal, the second surface having at least a partially overlapping area with the first surface of the battery terminal, wherein at least one end of the conductor located outside the overlapping area extends outward toward the outside of the top view contour of the battery body, for electrical connection with other single cells or prefabricated batteries; and a first fastening band area comprising at least three and no more than ten Intermittently distributed lines within the overlapping area form triangular or polygonal hot-welding spots, which together form a secondary first electrical connection channel between the first and second surfaces. A closed-loop connection between the centers of multiple hot-welding spots forms an enclosed area, used to keep the periphery and / or connection of at least the enclosed area between the first and second surfaces abutting and / or connected. A first conductive adhesive spot area, filling the enclosed area, includes first conductive adhesive. At least a portion of the first conductive adhesive spot area is connected to the first and second surfaces by the first conductive adhesive filling the gaps between the first and second surfaces at non-direct contact points, and after curing, abuts against them. The remaining portion is abutted against by direct contact points between the first and second surfaces, together forming a main first electrical connection channel. The battery terminals of the multiple prefabricated batteries are located on the same plane.

[0047] The objective of this invention is achieved through the following technical solution: a method for fabricating a planar battery pack, comprising the following steps: S1, arranging multiple individual battery cells in a planar array, and leveling the first surface of the top of the battery terminals; S2, applying pressure to both sides of the array of multiple individual battery cells, maintaining levelness through friction between the individual cells; S3, spraying conductive adhesive into the middle region of the first surface of the top of all individual battery terminals to form conductive adhesive circular spots; S4, spraying structural adhesive into the outer periphery of the first surface of the top of all individual battery terminals to form structural adhesive ring spots; S5, simultaneously pressing multiple conductors onto corresponding battery terminals, and applying equal pressure to the upper surfaces of the multiple conductors; S6, continuously performing three-point thermal welding on the annular band between the structural adhesive ring spots and conductive adhesive circular spots on the multiple battery terminals using laser welding equipment; S7, releasing the pressure to complete the fabrication of multiple pre-fabricated cells; S8, assembling the multiple pre-fabricated cells into a planar battery pack.

[0048] The present invention achieves the following technical effects:

[0049] By organically combining hot welding and conductive adhesive cold welding, the structural connection characteristics of hot welding and the electrical flux characteristics of cold welding are maximized, while avoiding mutual interference and performance impact. This ensures that the product's electrical flux is industry-leading, while also providing strong connection stability under strong vibration and significantly improving production efficiency. Attached Figure Description

[0050] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0051] Figure 1 This is a schematic diagram of the prefabricated battery of the present invention;

[0052] Figure 2 This is a top view schematic diagram of the prefabricated battery according to the first embodiment of the present invention;

[0053] Figure 3 This is a cross-sectional schematic diagram of the first embodiment of the present invention;

[0054] Figure 4 This is a schematic diagram of the first surface of the battery terminal according to the first embodiment of the present invention;

[0055] Figure 5 This is a schematic diagram of the first side of the second embodiment of the present invention;

[0056] Figure 6 This is a schematic diagram of the first side of the third embodiment of the present invention.

[0057] The reference numerals in the accompanying drawings of this invention are as follows:

[0058] 11-Battery body, 12-Battery terminal, 2-Conductor, 3-Thermal weld spot, 41-First conductive adhesive spot area, 42-Second conductive adhesive spot area, 421-Inner circle Tuesday, 422-Outer circle Wednesday, 5-Sealed zone area, 51-Inner circle Thursday, 52-Outer circle Friday, 61-First fastening zone area, 62-Second fastening zone area. Detailed Implementation

[0059] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0060] The components of the embodiments of the invention described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0061] In this invention, a "single battery cell" can be a cylindrical battery cell, a square battery cell, or a battery cell of other shapes, as long as it has battery terminals 12 that need to be connected to the conductor 2. In this invention, "connection" includes not only physical connection but also electrical connection.

[0062] like Figure 1 As shown, this invention protects a prefabricated battery. A "prefabricated battery" refers to a prefabricated single-cell battery and a conductor 2 connected together and sold and used as a whole. The single-cell battery includes a battery body 11 and battery terminals 12. The battery body 11 can be cylindrical or prismatic. The battery terminals 12, located within the top view of the battery body 11, protrude and connect to the top of the battery body 11, and have a first surface away from the battery body 11. The conductor 2 is used for stacking and electrically connecting with the battery terminals 12. The conductor 2 has a second surface close to the battery terminals 12, and the second surface and the first surface of the battery terminals 12 have an overlapping area. The overlapping area refers to the area where the first and second surfaces overlap in the height direction of the single-cell battery. The first and second surfaces attempt to contact each other in the overlapping area. One or both ends of the conductor 2 extend outwards from the top view of the battery body 11 for electrical connection with other single-cell batteries or prefabricated batteries. The conductor 2 may also extend outwards from the battery body 11 at both ends or all four sides.

[0063] The present invention provides a first fastening band area 61, such as Figures 2 to 4 As shown, the system includes three spaced-apart weld spots 3 arranged in a triangular pattern within the overlapping area. These weld spots 3 collectively form a secondary first electrical connection channel between the first and second surfaces. A closed-loop connection between the centers of the weld spots 3 forms an enclosed area, used to keep at least the periphery and / or connection of the enclosed area between the first and second surfaces abutting and / or connected. The number of weld spots 3 can be four or more, but not exceeding ten. Limiting the number of weld spots 3 avoids excessive interference between them, leading to a loss of connection strength. When there are four or more weld spots 3, the connecting lines between them form a polygon. The first and second surfaces are connected at the weld spots 3, and the connection points of the three weld spots 3 bring the first and second surfaces within the enclosed area closer together until they abut.

[0064] This invention provides a first conductive adhesive patch area 41, filling the enclosed area. This patch includes a first conductive adhesive. Within the first conductive adhesive patch area 41, the first conductive adhesive, which fills the gaps between the first and second surfaces at non-direct contact points, connects to and cures the first and second surfaces, forming abutment connections. In the gaps where non-direct contact points exist, the first conductive adhesive bonds the first and second surfaces. Other parts are connected by direct contact points between the first and second surfaces. The direct contact between the first and second surfaces in other parts prevents the filling of gaps with conductive adhesive. However, this direct contact achieves electrical communication between the first and second surfaces, forming a primary first electrical connection channel. In this invention, the electrical flux of the primary electrical connection channel is greater than that of the secondary electrical connection channels.

[0065] Furthermore, in the prefabricated battery of the present invention, the first and second surfaces within the overlapping area are substantially matched and bonded together. For example... Figure 3 As shown, both the first and second surfaces are planar; or the first surface is a concave surface with an arc and the second surface is a convex surface with an arc, or the first surface has a wave-like microstructure and the second surface also has a wave-like microstructure, so that the first and second surfaces can fit together almost completely, thereby improving the connection stability.

[0066] Furthermore, in the prefabricated battery of the present invention, the battery terminal 12 and the conductor 2 are metal conductors with similar thickness and similar melting points, which is suitable for achieving a reliable structural connection between them using a deep-penetration hot-welding process. The deep-penetration hot-welding process includes spot welding and laser welding. Unlike the submerged hot-melt welding process, the deep-penetration hot-weld weld spot 3 penetrates a larger dimension in the thickness direction of the battery terminal 12 and the conductor 2, thereby improving sufficient connection strength.

[0067] Furthermore, in the prefabricated battery of the present invention, the battery terminal 12 and the conductor 2 are metal conductors of the same thickness and material, thereby facilitating the deep-melt hot-welding connection process.

[0068] Furthermore, the prefabricated battery of the present invention also includes at least one second fastening band region 62 disposed around the outer periphery of the first fastening band region 61, such as... Figure 5 The diagram shows a second fastening zone 62, as shown. Figure 6 The diagram shows two second fastening band areas 62 on both sides. Each layer of the second fastening band area 62 includes at least three spaced lines forming a triangular hot-welding spot 3, used to press and / or connect the first and second surfaces of the second conductive adhesive spot area 42 formed between each layer of the second fastening band area 62 and the first fastening band area 61, or between two layers of the second fastening band area 62, and to form a secondary second electrical connection channel. At least a portion of the second conductive adhesive spot area 42 is filled with second conductive adhesive, forming a primary second electrical connection channel.

[0069] Furthermore, in the prefabricated battery of the present invention, each of the hot-welded weld spots 3 is located within the corresponding fastening zone, and there is a gap between the outer periphery and the two side boundaries of the corresponding fastening zone. Here, it means that the first surface and the second surface are directly connected at the hot-welded weld spot 3, and a fastening effect similar to a connection can be formed around the hot-welded weld spot 3. The area with this fastening effect is set as the fastening zone.

[0070] Furthermore, the prefabricated battery of the present invention, such as Figure 5 As shown, the triangle formed by the lines connecting the hot weld spots 3 in each layer of the fastening zone has an angle difference with the triangle formed by the lines connecting the hot weld spots 3 in adjacent fastening zones, thereby providing a more balanced structural connection in the circumferential direction.

[0071] Furthermore, the prefabricated battery of the present invention, such as Figure 6 As shown, the hot-welded weld spots 3 in the fastening zone of each layer are arranged in several straight lines. Although this method provides slightly less connection strength in the circumferential direction than the angle difference case, the connection continuity on the straight lines is better.

[0072] Furthermore, in the prefabricated battery of the present invention, there is a gap between the hot-welding spot 3 and the conductive adhesive, which ensures that during the deep-melt hot-welding process, the conductive adhesive will not cause the weld to be weak or the risk of welding explosion due to the inclusion of conductive adhesive in the hot-welding area.

[0073] Furthermore, the prefabricated battery of the present invention also includes a sealed zone 5, which surrounds the outermost fastening zone. The sealed zone 5 is fully filled with adhesive and is closed at both ends. The adhesive is bonded to the first surface and the second surface respectively, so that the adhesive forms a sealed cavity after curing. The function of the adhesive is to seal the conductive adhesive and the hot-welded weld spot 3 within the overlapping area, so that the conductive adhesive can cure in a sealed environment, thereby improving the curing effect of the conductive adhesive.

[0074] Furthermore, in the prefabricated battery of the present invention, there is a gap between the sealed zone 5 and each of the hot-welding spots 3, which ensures that during the deep-melt hot-welding process, there is no risk of weak welding or welding explosion due to the addition of adhesive in the hot-welding area.

[0075] Furthermore, in the prefabricated battery of the present invention, the adhesive is a structural adhesive, which further improves the structural connection stability between the battery terminal 12 and the conductor 2.

[0076] Furthermore, in the prefabricated battery of the present invention, the structural adhesive is a pressure-curing structural adhesive, such as an anaerobic adhesive, which provides a certain degree of structural locking effect in the initial stage of pressing the conductor 2 onto the battery terminal 12, ensuring the pressing accuracy.

[0077] Furthermore, in the prefabricated battery of the present invention, the structural adhesive is a fast-drying structural adhesive, such as polyurea, which allows the structural adhesive to cure rapidly after spraying, ensuring the curing quality of the conductive adhesive.

[0078] Furthermore, in the prefabricated battery of the present invention, the structural adhesive is a structural adhesive that does not easily swell or melt, thereby ensuring that the conductor 2 and the battery terminal 12 remain connected and do not separate during the recycling process of the prefabricated battery, and that the conductive adhesive and the deep-melt hot solder joint maintain their connection performance, thereby ensuring the overall secondary use of the prefabricated battery.

[0079] Furthermore, in the prefabricated battery of the present invention, the adhesive is a conductive adhesive, which is suitable for forming a main third electrical connection channel, further increasing the electrical flux and current stability between the battery terminal 12 and the conductor 2.

[0080] Furthermore, in the prefabricated battery of the present invention, a pad is further provided in the conductive adhesive patch area between the first surface and the second surface. The pad includes a conductive post with longitudinal electrical connection. The pad has an upper surface and a lower surface. The conductive post includes a conductor connection end located on the upper surface and the lower surface. At least the conductor connection end is respectively pressed against the first surface and the second surface, forming a first pressing point and a second pressing point. By providing the pad, the clamping force between the first surface and the second surface is increased, and the clamping force of the first pressing point and the second pressing point tends to be consistent, ensuring current flow and current stability.

[0081] Furthermore, in the prefabricated battery of the present invention, the conductor connection end is electrically connected to the first surface by the conductive adhesive provided thereon, and can be integrally connected to the second surface, for example, the conductive post and the conductor 2 can form an integral structure.

[0082] Furthermore, in the prefabricated battery of the present invention, the conductive pillar is an elastic conductive mass, which can be a clump-shaped conductive body 2 formed by cutting long metal sheets, conductor filaments, or filament braids. Alternatively, the conductive mass can be a clump-shaped metal or non-metal conductor filament, which is filled with conductive adhesive and cured to form a conductive pillar. In another embodiment, the conductive pillar can be a folded metal sheet or a conductive package containing conductive powder, wherein after the first and second sides are squeezed and ruptured, the conductive powder overflows and forms an abutment electrical connection with the first and second sides. In another embodiment, conductive adhesive is coated on the outer periphery of the conductive pillar and, after compression, seals the outer periphery of the conductive pillar.

[0083] Furthermore, in the prefabricated battery of the present invention, the hot-welded weld spots 3 located in the same fastening zone are on the same circumference, thereby ensuring that the fastening zone has a consistent circumferential width and can provide the most balanced circumferential connection strength.

[0084] Furthermore, in the prefabricated battery of the present invention, the hot-welded weld spots 3 within the same fastening zone are evenly and symmetrically distributed. When there are three hot-welded weld spots 3, they form an equilateral triangle, and multiple hot-welded weld spots 3 form a regular polygon.

[0085] Furthermore, in the prefabricated battery of the present invention, the same second conductive spot area is annular, forming an inner circle circumference 421 and an outer circle circumference 422, and the sealed zone area 5 is annular, forming an inner circle circumference 51 and an outer circle circumference 52. The circle circumference 1, the inner circle circumference 421, the outer circle circumference 422, the inner circle circumference 51, and the outer circle circumference 52 are set as concentric circles to ensure that the connection force provided by each annular connection layer is balanced.

[0086] With the prefabricated battery of the present invention, three current paths are formed between the battery terminal 12 and the conductor 2. The conductive adhesive forms the first current path, the deep melt hot weld spot 3 forms the second current path, and the conductive adhesive in the sealed zone 5 forms the third current path. The first current path has the largest current flow and is the main current path of this structure.

[0087] For the overlapping connection between two busbars, the present invention also provides a connection structure, including: a first busbar having a first surface; a second busbar for longitudinally stacking with the first busbar, the second busbar having a second surface close to the first busbar, the second surface and the first surface of the first busbar having at least a partially overlapping area; a first fastening band area 61 including at least three and no more than ten hot-welding spots 3 arranged at intervals in the overlapping area, the hot-welding spots 3 collectively forming a secondary first electrical connection between the first surface and the second surface. The channel, the closed loop connecting the centers of the multiple hot weld spots 3 forms a closed area, which is used to keep the periphery and / or connection of at least the area within the closed area between the first surface and the second surface abutting and / or connected; the first conductive adhesive spot area 41, filled in the closed area, includes the first conductive adhesive, at least a portion of the first conductive adhesive spot area 41 is connected to the first surface and the second surface respectively by the first conductive adhesive filled in the non-direct contact point gap between the first surface and the second surface and then abutting after curing, the other part is abutting and connected by the direct contact point between the first surface and the second surface, together forming the main first electrical connection.

[0088] The present invention also provides a planar battery pack comprising a plurality of prefabricated batteries arranged in a planar manner. Each prefabricated battery comprises: a single cell, the single cell including a battery body 11 and a battery terminal 12, the battery terminal 12 being located within the top view profile of the battery body 11 and protruding from the top of the battery body 11, and having a first surface away from the battery body 11; a conductor 2 for longitudinally stacking with the battery terminal 12, the conductor 2 having a second surface near the battery terminal 12, the second surface having at least a partially overlapping area with the first surface of the battery terminal 12, wherein at least one end of the conductor 2 located outside the overlapping area extends outward toward the outside of the top view profile of the battery body 11 for electrical connection with other single cells or prefabricated batteries; and a first fastening band area 61, comprising at least three and no more than ten Intermittently distributed lines within the overlapping area form triangular or polygonal hot-welding spots 3. These hot-welding spots 3 collectively form a secondary first electrical connection channel between the first and second surfaces. A closed-loop connection between the centers of multiple hot-welding spots 3 forms an enclosed area, used to keep at least the periphery and / or connection of the enclosed area between the first and second surfaces. A first conductive adhesive spot area 41, filled within the enclosed area, includes first conductive adhesive. At least a portion of the first conductive adhesive spot area 41 is connected to the first and second surfaces by the first conductive adhesive filling the gaps between the first and second surfaces at non-direct contact points, and after curing, forms an abutment connection. The remaining portion is connected by direct contact points between the first and second surfaces, collectively forming a main first electrical connection channel. The battery terminals 12 of the multiple prefabricated batteries are located on the same plane. Based on this, by controlling the consistent downward pressure height of the conductor 2 on the first surface of the leveled battery terminal 12, the current flow between all battery terminals 12 and the conductor 2 can be made consistent, greatly improving process efficiency.

[0089] In response to the aforementioned planar battery pack, the present invention also provides a method for preparing the planar battery pack, comprising the following steps: S1, arranging multiple individual battery cells in a planar array, and leveling the top first surface of the battery terminal 12; S2, applying pressure to both sides of the multiple individual battery cells array, maintaining leveling through friction between the individual cells; S3, spraying conductive adhesive into the middle region of the top first surface of the battery terminal 12 of all individual cells to form conductive adhesive circular spots; S4, spraying structural adhesive into the outer periphery of the top first surface of the battery terminal 12 of all individual cells to form structural adhesive ring spots; S5, simultaneously pressing multiple conductors 2 onto the corresponding battery terminal 12, and applying equal pressure to the upper surfaces of the multiple conductors 2; S6, continuously performing three-point thermal welding on the annular band between the structural adhesive ring spots and the conductive adhesive circular spots on the multiple battery terminal 12 using laser welding equipment; S7, releasing the pressure to complete the preparation of multiple prefabricated cells; S8, assembling the multiple prefabricated cells into a planar battery pack. The process steps for assembling multiple prefabricated battery packs into a planar battery pack are not limited here. Since all battery terminals 12 are leveled, it is ensured that the current flow between the battery terminals 12 and the conductor 2 can be consistent using laser continuous welding process, which greatly improves the process efficiency.

[0090] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A prefabricated battery, characterized in that, include: A single battery cell includes a battery body and battery terminals, wherein the battery terminals, located within the top view outline of the battery body, protrude and connect to the top of the battery body, and have a first side away from the battery body; A conductor for longitudinally stacking with the battery terminal, the conductor having a second surface near the battery terminal, the second surface having at least a partially overlapping area with the first surface of the battery terminal, wherein at least one end of the conductor located outside the overlapping area extends outward toward the outside of the top view profile of the battery body for electrical connection with other single cells or prefabricated cells. The first fastening zone includes at least three and no more than ten hot-welded weld spots arranged at intervals in the overlapping area, forming triangular or polygonal lines. The hot-welded weld spots together form a secondary first electrical connection channel between the first surface and the second surface. The closed-loop lines between the centers of the multiple hot-welded weld spots form an enclosed area for keeping the periphery and / or the area inside the enclosed area between the first surface and the second surface abutted and / or connected. The first conductive adhesive patch area, which fills the enclosed area, includes the first conductive adhesive. At least a portion of the first conductive adhesive patch area is connected to the first and second surfaces by the first conductive adhesive filling the gaps between the first and second surfaces through non-direct contact points, and then bonded after curing. The other portion is bonded by direct contact points between the first and second surfaces, together forming the main first electrical connection channel.

2. The prefabricated battery as described in claim 1, characterized in that, The first and second surfaces within the overlapping area are approximately matched and fitted together.

3. The prefabricated battery as described in claim 1, characterized in that, The battery terminals and the conductor are metal conductors with similar thickness and melting point, which is suitable for achieving a reliable structural connection between them using a deep-penetration hot-welding process.

4. The prefabricated battery as described in claim 1, characterized in that, The battery terminals and the conductor are metal conductors of the same thickness and material.

5. The prefabricated battery as described in claim 1, characterized in that, The hot weld spot is obtained by a deep penetration hot welding connection process.

6. The prefabricated battery as described in claim 1, characterized in that, It also includes at least one second fastening band area disposed around the periphery of the first fastening band area. Each second fastening band area includes at least three and no more than ten hot-welding spots formed by connecting lines spaced apart therein, which are used to press and / or connect the first and second surfaces in the second conductive adhesive spot area formed between each second fastening band area and the first fastening band area, or between two second fastening band areas, and to form a secondary second electrical connection channel. At least a portion of the second conductive adhesive spot area is filled with second conductive adhesive to form a primary second electrical connection channel.

7. The prefabricated battery as described in any one of claims 1-6, characterized in that, Each of the hot-welded weld spots is located within the corresponding fastening zone, and there is a gap between the outer periphery and the two side boundaries of the corresponding fastening zone.

8. The prefabricated battery as described in claim 6, characterized in that, There is an angular difference between the triangle or polygon formed by the connecting lines of the hot weld spots in each of the fastening zones and the triangle or polygon formed by the connecting lines of the hot weld spots in adjacent fastening zones.

9. The prefabricated battery as described in claim 6, characterized in that, The hot-welded weld spots in the fastening zone of each layer are arranged in several straight lines.

10. The prefabricated battery as described in any one of claims 1-6, characterized in that, There is a gap between the hot-welded weld spot and the conductive adhesive.

11. The prefabricated battery as described in any one of claims 1-6, characterized in that, The conductive adhesive is a cold soldering adhesive that can be cured at room temperature.

12. The prefabricated battery as described in any one of claims 1-6, characterized in that, It also includes at least one sealed zone, which surrounds the outer periphery of the outermost fastening zone. The sealed zone is filled with adhesive and is closed at both ends. The adhesive is bonded to the first surface and the second surface respectively, so that the adhesive forms a sealed cavity after curing.

13. The prefabricated battery as described in claim 12, characterized in that, The sealed zone is spaced apart from each of the hot-welding spots.

14. The prefabricated battery as described in claim 12, characterized in that, The adhesive is a structural adhesive.

15. The prefabricated battery as described in claim 14, characterized in that, The structural adhesive is a pressure-curing structural adhesive.

16. The prefabricated battery as described in claim 14, characterized in that, The structural adhesive is a fast-drying structural adhesive.

17. The prefabricated battery as described in claim 14, characterized in that, The structural adhesive is a structural adhesive that does not easily swell or melt.

18. The prefabricated battery as claimed in claim 12, characterized in that, The adhesive is a conductive adhesive, suitable for forming a primary third electrical connection channel.

19. The prefabricated battery as described in any one of claims 1-6, characterized in that, The conductive adhesive patch area between the first surface and the second surface is further provided with a pad. The pad includes a conductive post with longitudinal electrical connection. The pad has an upper surface and a lower surface. The conductive post includes a conductor connection end located on the upper surface and the lower surface. At least the conductor connection end is respectively pressed against the first surface and the second surface to form a first pressing point and a second pressing point.

20. The prefabricated battery as claimed in claim 19, characterized in that, At least the conductor connection end and the first surface are electrically connected by the conductive adhesive.

21. The prefabricated battery as described in claim 19, characterized in that, The pad and the conductor are an integrated structure.

22. The prefabricated battery as described in claim 19, characterized in that, The conductive pillar and the conductive body are an integrated structure.

23. The prefabricated battery as described in claim 19, characterized in that, The conductive pillar is an elastic conductive mass.

24. The prefabricated battery as described in claim 23, characterized in that, The conductive cluster is a cluster of conductive material formed from metal cutting strips, conductor filaments, or filament braids.

25. The prefabricated battery as described in claim 23, characterized in that, The conductive group is a short filament of metallic or non-metallic conductor, which is filled with conductive adhesive and cured to form a conductive column.

26. The prefabricated battery as described in claim 19, characterized in that, The conductive post is a folded metal sheet.

27. The prefabricated battery as claimed in claim 19, characterized in that, The conductive post is a conductive package containing conductive powder. After the package is broken by the first and second sides, the conductive powder forms an abutment electrical connection with the first and second sides respectively.

28. The prefabricated battery as described in claim 19, characterized in that, The conductive adhesive is coated on the outer periphery of the conductive post and then sealed after compression.

29. The prefabricated battery as described in any one of claims 1-6, characterized in that, The hot weld spots located within the same fastening zone are situated on the same circumference.

30. The prefabricated battery as described in any one of claims 1-6, characterized in that, The hot-welded weld spots within the same fastening zone are evenly and symmetrically distributed.

31. The prefabricated battery as described in any one of claims 1-6, characterized in that, The hot-welded weld spots within the same fastening zone are distributed in an equilateral triangle pattern.

32. The prefabricated battery as described in claim 6, characterized in that, The same second conductive spot area is annular, forming an inner circumference and an outer circumference.

33. The prefabricated battery as described in claim 32, characterized in that, The inner circle (circle 2) and the outer circle (circle 3) are concentric circles.

34. The prefabricated battery as described in claim 29, characterized in that, All the circles mentioned are concentric circles.

35. The prefabricated battery as described in claim 34, characterized in that, The same second conductive spot area is annular, forming an inner circumference and an outer circumference, and all of the circumferences, inner circumferences, and outer circumferences are concentric circles.

36. The prefabricated battery as described in claim 12, characterized in that, The enclosed zone is circular, forming an inner circle around Thursday and an outer circle around Friday.

37. The prefabricated battery as described in claim 36, characterized in that, All of the aforementioned circles are concentric circles, and the same second conductive spot area is an annular ring, forming an inner circle Tuesday and an outer circle Wednesday. All of the aforementioned circles Monday, inner circle Tuesday, outer circle Wednesday, inner circle Thursday, and outer circle Friday are concentric circles.

38. A connection structure, characterized in that, include: The first busbar has the first face; A second busbar is used for longitudinal stacking connection with the first busbar. The second busbar has a second side close to the first busbar, and the second side has at least a partially opposite overlapping area with the first side of the first busbar. The first fastening zone includes at least three and no more than ten hot-welded weld spots arranged at intervals in the overlapping area, forming triangular or polygonal lines. The hot-welded weld spots together form a secondary first electrical connection channel between the first surface and the second surface. The closed-loop lines between the centers of the multiple hot-welded weld spots form an enclosed area for keeping the periphery and / or the area inside the enclosed area between the first surface and the second surface abutted and / or connected. The first conductive adhesive patch area, which fills the enclosed area, includes the first conductive adhesive. At least a portion of the first conductive adhesive patch area is connected to the first and second surfaces by the first conductive adhesive filling the gaps between the first and second surfaces through non-direct contact points, and then bonded after curing. The other portion is bonded by direct contact points between the first and second surfaces, together forming the main first electrical connection channel.

39. A planar battery pack comprising a plurality of prefabricated cells arranged in a planar manner, characterized in that, Each of the prefabricated cells includes: A single battery cell includes a battery body and battery terminals, wherein the battery terminals, located within the top view outline of the battery body, protrude and connect to the top of the battery body, and have a first side away from the battery body; A conductor for longitudinally stacking with the battery terminal, the conductor having a second surface near the battery terminal, the second surface having at least a partially overlapping area with the first surface of the battery terminal, wherein at least one end of the conductor located outside the overlapping area extends outward toward the outside of the top view profile of the battery body for electrical connection with other single cells or prefabricated cells. The first fastening zone includes at least three and no more than ten hot-welded weld spots arranged at intervals in the overlapping area, forming triangular or polygonal lines. The hot-welded weld spots together form a secondary first electrical connection channel between the first surface and the second surface. The closed-loop lines between the centers of the multiple hot-welded weld spots form an enclosed area for keeping the periphery and / or the area inside the enclosed area between the first surface and the second surface abutted and / or connected. The first conductive adhesive patch area, which fills the enclosed area, includes the first conductive adhesive. At least a portion of the first conductive adhesive patch area is connected to the first and second surfaces by the first conductive adhesive filling the gaps between the first and second surfaces, and then abutted after curing. The other portion is abutted by the direct abutting points between the first and second surfaces, together forming the main first electrical connection channel. The battery terminals of the plurality of prefabricated batteries are located on the same plane.

40. A method for preparing a planar battery pack, characterized in that the steps include... include: S1, a planar array of multiple individual battery cells, with the top first surface of the battery terminals leveled; S2, pressure is applied to both sides of the multiple individual battery arrays, and the friction between each individual battery keeps them level; S3, spray conductive adhesive onto the middle area of ​​the first surface of the top of all individual battery terminals to form conductive adhesive spots; S4, structural adhesive is sprayed onto the outer periphery of the first surface of the top of the battery terminal of all individual cells to form structural adhesive ring spots; S5, multiple conductors are simultaneously pressed onto the corresponding battery terminals, and equal pressure is applied to the upper surfaces of the multiple conductors; S6, using laser welding equipment, three-point hot welding is continuously performed on the annular band between the structural adhesive ring spots and conductive adhesive round spots on the multiple battery terminals; S7, depressurization completes the fabrication of multiple pre-fabricated cells; S8, assemble the plurality of prefabricated cells into a planar battery pack.

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