CN-122025955-A - 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, wherein an overlapping area is formed between the battery pole and the electric conductor, a first fastening band area and a first conductive adhesive spot area are arranged in the overlapping area, and a thermal welding connection and a conductive adhesive cold welding connection organic combination is used for exerting the structural connection characteristic of the thermal welding connection and the electric flux characteristic of the cold welding connection to the greatest extent, avoiding the mutual interference of the two to influence the performance of each other, ensuring the electric flux of a product to be advanced in the industry, and simultaneously having strong connection stability under strong vibration and greatly improving the production efficiency.

Inventors

• WANG ZIQI
• WANG CHUN

Assignees

• 汪子琪
• 汪纯

Dates

Publication Date

20260512

Application Date

20221221

Claims (20)

1. 1. A prefabricated battery, comprising: The single battery comprises a battery body and a battery post, wherein the battery post positioned in the overlooking outline of the battery body is convexly connected to the top of the battery body and is provided with a first surface far away from the battery body; An electrical conductor for longitudinal stacking connection with the battery post, the electrical conductor having a second face adjacent the battery post, the second face having an overlapping region at least partially opposite the first face of the battery post, wherein at least one end of the electrical conductor outside the overlapping region extends outside the top-view profile side of the battery body for electrical connection with other of the unit cells or a pre-formed battery; a first fastening band region comprising at least three and not more than ten connecting lines which are arranged in the overlapped region at intervals to form triangular or polygonal hot welding spots, wherein the hot welding spots jointly form a secondary first electric connection channel between the first surface and the second surface, closed loop connecting lines among centers of the hot welding spots form a surrounding area, and the surrounding area is used for keeping at least the periphery and inner area of the surrounding area between the first surface and the second surface to be abutted and/or connected; The first conductive adhesive spot area is filled in the surrounding area and comprises first conductive adhesive, at least one part of the first conductive adhesive spot area is filled in a gap of indirect contact points between the first surface and the second surface, the first conductive adhesive spot area is respectively connected with the first surface and the second surface and is in contact connection after solidification, and other parts of the first conductive adhesive spot area are in contact connection with the direct contact points between the first surface and the second surface to jointly form a main first electric connection channel.
2. 2. The preformed battery of claim 1 wherein said first face and said second face within said overlap region are substantially matingly engaged.
3. 3. The prefabricated battery of claim 1 wherein said battery post and said electrical conductor are metal conductors having similar thicknesses and similar melting points adapted to be connected together by a deep-melt thermal welding process.
4. 4. The prefabricated battery of claim 1 wherein said battery post and said electrical conductor are of equal thickness and material.
5. 5. The preformed battery of claim 1, wherein the thermal weld spots are made by a deep-melt thermal welding process.
6. 6. The prefabricated battery of claim 1 further comprising at least one layer of second fastening strip disposed on the periphery of said first fastening strip, each layer of said second fastening strip comprising at least three and not more than ten lines of wire disposed therein in spaced apart relation forming a triangular or polygonal thermal weld for abutting and/or connecting said first and second faces within a second conductive adhesive patch region formed between each layer of said second fastening strip and said first fastening strip or between two layers of said second fastening strip and forming a secondary second electrical connection channel, at least a portion of said second conductive adhesive patch region being filled with a second conductive adhesive to form a primary second electrical connection channel.
7. 7. The prefabricated battery according to any one of claims 1 to 6, wherein each of the thermal welding spots is located in the corresponding fastening band with a gap between the outer circumference and both side boundaries of the corresponding fastening band.
8. 8. The prefabricated battery of claim 6 wherein the lines of heat welding spots in each layer of said fastening strip are of a triangular or polygonal shape with an angular difference between the lines of heat welding spots in adjacent said fastening strip.
9. 9. The preformed battery of claim 6 wherein the heat weld spots in each layer of said fastening strap are aligned in a plurality of lines.
10. 10. The preformed battery of any one of claims 1-6, wherein a gap is provided between the thermal weld spot and the conductive paste.
11. 11. The preformed battery of any one of claims 1-6, wherein the conductive paste is a cold-welded paste that is curable at ambient temperature.
12. 12. The prefabricated battery according to any one of claims 1-6, further comprising at least one sealing band around the periphery of the outermost fastening band, wherein the sealing band is filled with an adhesive and sealed from the head to the tail, and the adhesive is bonded to the first face and the second face respectively, so that a sealed cavity is formed after the adhesive is cured.
13. 13. The preformed battery of claim 12 wherein said containment band is spaced from each of said thermal welds.
14. 14. The preformed battery of claim 12 wherein the adhesive is a structural adhesive.
15. 15. The preformed battery of claim 14 wherein the structural adhesive is a crimp-cured structural adhesive.
16. 16. The preformed battery of claim 14 wherein the structural adhesive is a quick-setting structural adhesive.
17. 17. The preformed battery of claim 14 wherein the structural adhesive is a structural adhesive that does not readily swell or melt.
18. 18. The preformed battery of claim 12 wherein the adhesive is a conductive adhesive adapted to form a primary third electrical connection path.
19. 19. The preformed battery of any one of claims 1-6, wherein the conductive patch area between the first and second faces is further provided with a spacer comprising a conductive post having a longitudinal electrical connection, the spacer having an upper surface and a lower surface, the conductive post comprising conductor connecting ends at the upper and lower surfaces, at least the conductor connecting ends abutting the first and second faces, respectively, to form first and second abutting points, respectively.
20. 20. The preformed battery of claim 19 wherein at least said conductor connection end is in abutting electrical connection with said first face by said conductive adhesive.

Description

Prefabricated battery, connecting structure, planar battery pack and preparation method of planar battery pack Technical Field The invention belongs to the technical field of new energy, and particularly relates to a prefabricated battery, a connecting structure, a planar battery pack and a preparation method of the prefabricated battery. Background As the capacity of single cells increases, particularly power cells, the maximum electrical flux requirements for the electrical connection between the corresponding surfaces of the two conductors between the battery post and the busbar also increase, requiring high reliability of the electrical and structural connections. The prior art connection technology mainly comprises a deep-melting hot welding connection (including a spot welding process and a laser welding process), latent fusion hot welding connection and cold welding connection to realize reliable connection between the battery pole and the busbar. For the deep-melting hot welding connection technology, although the connection strength is higher, the welding spots of the metal local welding are usually smaller and the sectional area is limited, so that the electric flux of the 2-point or 4-point welding spots of the original small-capacity battery can not meet the high electric flux requirement when the high-capacity single body is charged and discharged at a high rate, and a plurality of welding spots are required to be combined and spliced into a larger welding spot. However, because the current penetration type welding process of spot welding is greatly affected by various factors, the abnormal connection strength and contact resistance such as cold joint/false joint are most likely to be caused, the connection reliability of the fixed-point energy-gathering type welding process of laser welding is guaranteed, but when the welding is electrically connected in groups, the consistency of welding quality can be guaranteed only at the same distance, and the single-sided integral laser welding yield of the battery pack is obviously higher than that of the laser welding at two ends due to the tolerance of the heights of multiple batteries, on the other hand, the metal welding is usually carried out by only one welding machine, the point-by-point welding is low in production efficiency, the time consumption of multiple points is long, and therefore the single-pole column electric connection procedure at the top is usually the bottleneck point in the whole production flow. For latent fusion hot welding connection and cold welding connection technologies, although the conductive adhesive spots crimped by the cold welding adhesive filler are larger, the electric flux under certain crimping pressure is larger, and the requirement of high electric flux can be met, the stripping force of the adhesive connection and the shallow melting connection is weaker, and the connection stability of a single connection point is insufficient. In order to maintain the reliability of the electric connection point, a mode of strengthening the structure between batteries (such as full glue injection between batteries) is generally adopted under the shallow fusion welding process to weaken the stress of the electric connection point under strong shock so as to strengthen the reliability of the electric connection point, but the external structure has higher cost and heavier weight (influencing the index of grouped weight energy density), and the production convenience is not enough, and the improvement is urgently needed. Therefore, how to further enhance the reliability of the electrical connection point with low weight gain and convenience under the condition of weak electrical connection of the top pole is one of the main technical matters of the group technology that the common electrical connection is towards precise electrical connection. In summary, there is no connection structure between a battery post and an electrical conductor that satisfies both the electrical connection flux and the structural connection strength in the prior art. Disclosure of Invention Therefore, the invention aims to overcome the defects in the prior art and provide a prefabricated battery, a connecting structure, a planar battery pack and a preparation method thereof, wherein the prefabricated battery can simultaneously meet the electric flux and the structural connection strength of electric connection. The invention aims at completing the technical scheme that the prefabricated battery comprises a single battery, wherein the single battery comprises a battery body and a battery pole, and the battery pole positioned in the overlooking outline of the battery body is convexly connected to the top of the battery body and is provided with a first surface far away from the battery body; the battery terminal comprises a battery body, an electric conductor, a first fastening band, a second fastening band and a second fastening band, wherein the elect