Soft package battery and battery pack

Abstract

The utility model provides a soft package battery and a battery pack. The soft package battery comprises a shell, an electrode assembly and a plurality of tightening belts, the shell is provided with an accommodating cavity; the electrode assembly is contained in the containing cavity, the electrode assembly is provided with a first side face and a second side face which are opposite in the first direction, and the electrode assembly is provided with a third side face and a fourth side face which are opposite in the second direction; the plurality of lacing belts are arranged in the third direction of the electrode assembly, one end of each lacing belt is attached to the first side face or the second side face, and the other end of each lacing belt bypasses the third side face and / or the fourth side face and is attached to the corresponding second side face or the first side face; the first direction, the second direction and the third direction are perpendicular to each other, a gluing layer is arranged between the lacing belt and the first side face and / or the second side face, and the technical problem that the electrode assembly is prone to making contact with the inner wall of the shell can be solved by arranging the gluing layer at the specific position on the lacing belt.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a soft-pack battery and a battery pack. Background Art

[0002] In recent years, the new energy industry has developed rapidly. Lithium-ion batteries have gradually become the mainstream products in the new energy industry due to their high energy density, safety and environmental protection. According to different packaging methods, lithium-ion batteries can be divided into three categories: soft-pack, square-shell and cylindrical batteries. Soft-pack batteries have attracted much attention because of their relatively simple structure and relatively simple manufacturing process.

[0003] In practical applications, in order to increase the structural stability and energy density of soft-pack batteries and facilitate battery manufacturing and assembly, the electrode assembly usually needs to be bundled with tape in the circumference. However, the use of such tape bundling method increases the side dimensions of the electrode assembly, which will cause the side of the electrode assembly to easily contact the inner wall of the shell when the electrode assembly is packaged into the shell, thereby affecting the packaging process. On the other hand, the glue on the tape will melt due to the heat sealing of the shell and affect the heat sealing effect, thereby reducing the product production yield. Utility Model Content

[0004] In view of the above shortcomings of the prior art, the utility model provides a soft-pack battery and a battery pack, which improves the technical problem that the electrode assembly is easily in contact with the inner wall of the shell by arranging a rubber coating layer at a specific position on the tightening belt.

[0005] To achieve the above-mentioned purpose and other related purposes, the utility model provides a soft-pack battery, which includes a shell, an electrode assembly and a plurality of tightening bands; the shell is provided with a accommodating cavity; the electrode assembly is accommodated in the accommodating cavity, the electrode assembly has a first side surface and a second side surface relative to each other in a first direction, and the electrode assembly has a third side surface and a fourth side surface relative to each other in a second direction; a plurality of tightening bands are arranged along the third direction of the electrode assembly, one end of the tightening band is attached to the first side surface or the second side surface, and the other end of the tightening band bypasses the third side surface and / or the fourth side surface and is attached to the corresponding second side surface or the first side surface; the first direction, the second direction and the third direction are perpendicular to each other, and a coating layer is provided between the tightening band and the first side surface and / or the second side surface.

[0006] In an example of a soft-pack battery of the present invention, the tightening band includes a starting area, a middle area and a terminal area arranged in sequence, the starting area is located on one of the first side surface and the second side surface, the terminal area and the starting area are located on the same side, the middle area includes a first area corresponding to the third side surface, a third area corresponding to the fourth side surface, and a second area located between the first area and the third area, the second area corresponds to the other of the first side surface and the second side surface, and a coating layer is arranged between the starting area and the terminal area and the electrode assembly.

[0007] In an example of the soft-pack battery of the present invention, a glue coating layer is provided between the second region and the electrode assembly.

[0008] In an example of a soft-pack battery of the present invention, the tightening band includes a starting area, a middle area and a terminal area which are arranged in sequence, and a plurality of tightening bands arranged along the third direction are arranged on both sides of the second direction of the electrode assembly, the starting area is located on one of the first side surface and the second side surface, the terminal area is located on the other of the first side surface and the second side surface, the middle area is arranged corresponding to the third side surface or the fourth side surface, and a coating layer is arranged between the starting area and the terminal area and the electrode assembly.

[0009] In an example of the soft-pack battery of the present invention, the number of the multiple tightening bands located on the side where the third side is located is the same as the number of the multiple tightening bands located on the side where the fourth side is located, and the positions are corresponding.

[0010] In an example of the soft-pack battery of the present invention, a plurality of tightening bands located on the side where the third side is located are arranged alternately with a plurality of tightening bands located on the side where the fourth side is located.

[0011] In an example of the soft-pack battery of the present invention, the electrode assembly includes a wound diaphragm, the end of the wound diaphragm is located on the first side or the second side, and the tightening band covers at least a portion of the end.

[0012] In an example of the soft-pack battery of the present invention, the starting area covers at least a portion of the end.

[0013] In an example of a soft-pack battery of the present invention, the electrode assembly includes a diaphragm, which is a stacked structure formed by repeated bending. The diaphragm includes a first end and a second end, the first end is located on one of the first side surface and the second side surface, and the second end is located on the other of the first side surface and the second side surface, and the tightening band covers at least a portion of the first end and at least a portion of the second end.

[0014] In an example of the soft-pack battery of the utility model, along the second direction, the accommodating cavity includes a first groove and a second groove arranged opposite to each other, along the first direction and the third direction, the edge of the first groove extends outward with a first flange, and the edge of the second groove extends outward with a second flange, and the first flange is arranged opposite to the second flange and is fixedly connected.

[0015] The utility model also provides a battery pack, which comprises any one of the above-mentioned secondary batteries.

[0016] In the soft-pack battery of the utility model, multiple tightening bands are arranged along the third direction of the electrode assembly, one end of the tightening band is attached to the first side surface or the second side surface, and the other end of the tightening band bypasses the third side surface and / or the fourth side surface and is attached to the corresponding second side surface or the first side surface. This arrangement can not only increase the structural stability and energy density of the soft-pack battery, but also facilitate the manufacturing and assembly of the battery. At the same time, since a rubber coating layer is provided between the tightening band and the first side surface and / or the second side surface, and no rubber coating layer is provided between the tightening band and the third side surface and the fourth side surface, the width of the electrode assembly in the second direction can be reduced, the technical problem that the electrode assembly is easily in contact with the inner wall of the shell can be improved, and the product production yield is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a schematic diagram of the overall structure of an embodiment of a soft-pack battery of the utility model;

[0019] Figure 2 This is an exploded schematic diagram of the overall structure of an embodiment of the soft-pack battery of the utility model;

[0020] Figure 3 This is a schematic structural diagram of a wound structure electrode assembly of an embodiment of a soft-pack battery of the utility model;

[0021] Figure 4 This is a front view of a wound structure electrode assembly of an embodiment of a soft-pack battery of the utility model;

[0022] Figure 5 A schematic structural diagram of a wound structure electrode assembly from another perspective of an embodiment of a soft-pack battery of the utility model;

[0023] Figure 6 The utility model is a soft pack battery of one embodiment Figure 4 AA section view;

[0024] Figure 7 Another embodiment of the soft pack battery of the utility model Figure 4 AA section view;

[0025] Figure 8 A schematic structural diagram of a wound structure electrode assembly from another perspective of another embodiment of a soft-pack battery of the utility model;

[0026] Fig. 9Another embodiment of the soft pack battery of the utility model Figure 8 sectional view of

[0027] Fig.10 This is a schematic structural diagram of a stacked structure electrode assembly of an embodiment of a soft-pack battery of the utility model;

[0028] Fig.11 This is a front view of a stacked structure electrode assembly of an embodiment of a soft-pack battery of the utility model;

[0029] Fig.12 A schematic structural diagram of a stacked structure electrode assembly from another perspective of an embodiment of a soft-pack battery of the utility model;

[0030] Fig.13 The utility model is a soft pack battery of one embodiment Fig.11 BB cross-sectional view;

[0031] Fig.14 Another embodiment of the soft pack battery of the utility model Fig.11 BB cross-sectional view;

[0032] Fig.15 A schematic structural diagram of a stacked structure electrode assembly from another perspective of another embodiment of a soft-pack battery of the utility model;

[0033] Fig.16 Another embodiment of the soft pack battery of the utility model Fig.15 sectional view of

[0034] Fig.17 This is a front view of an electrode assembly of another embodiment of the soft-pack battery of the utility model;

[0035] Fig.18 A schematic diagram of an embodiment of a battery pack of the utility model;

[0036] Fig.19 It is a schematic diagram of an embodiment of the electronic device of the present utility model.

[0037] Component number description

[0038] 1. Electronic device; 10. Battery pack; 100. Soft-pack battery; 110. Shell; 111. First shell; 112. Second shell; 113. First groove; 114. Second groove; 115. First flange; 116. Second flange; 120. Electrode assembly; 121. Pole piece; 122. Diaphragm; 1221. End; 1222. First end; 1223. Second end; 123. First side; 124. Second side; 125. Third side; 126. Fourth side; 127. Positive pole ear; 128. Negative pole ear; 130. Glue coating; 140. Tightening belt; 141. Starting area; 142. Middle area; 1421. First area; 1422. Second area; 1423. Third area; 143. Terminal area. DETAILED DESCRIPTION

[0039] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and the features in the embodiments can be combined with each other without conflict. It should also be understood that the terms used in the embodiments of the present invention are intended to describe specific implementation schemes, rather than to limit the scope of protection of the present invention. The test methods for which specific conditions are not specified in the following examples are usually carried out under conventional conditions or under the conditions recommended by the manufacturers.

[0040] When numerical ranges are given in the embodiments, it should be understood that unless otherwise specified in the present invention, both endpoints of each numerical range and any value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention are in accordance with the prior art mastery of those skilled in the art and the description of the present invention, and any prior art methods, equipment and materials similar or equivalent to the methods, equipment and materials in the embodiments of the present invention can also be used to implement the present invention.

[0041] It should be noted that the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of description and are not used to limit the scope of implementation of the present utility model. Changes or adjustments to their relative relationships should be regarded as the scope of implementation of the present utility model without substantially changing the technical content.

[0042] In the present application, the soft pack battery includes a shell and an electrode assembly, wherein the electrode assembly is contained in the shell, and the electrode assembly is a component in the cylindrical battery where electrochemical reactions occur. The shell may contain one or more electrode assemblies.

[0043] The electrode assembly is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet includes a positive electrode collector and a positive electrode active material, and the positive electrode active material is coated on the surface of the positive electrode collector. The negative electrode sheet includes a negative electrode collector and a negative electrode active material, and the negative electrode active material is coated on the surface of the negative electrode collector. In order to increase the structural stability and energy density of the soft-pack battery and facilitate the manufacture and assembly of the battery, the circumference of the electrode assembly usually needs to be bundled with tape.

[0044] The shell is usually obtained by punching holes, and a single or double punching method can be used to form a cavity for accommodating the electrode assembly. In this embodiment, a double punching method is used, and the electrode assembly is first placed, and then the two parts of the shell are folded in half for packaging. The shell is usually made of aluminum-plastic film, which includes a heat-sealing layer, an aluminum layer, and an outer layer from the inside to the outside. When the heat-sealing layer is used to package the battery in the shell, it is first heated and melted, and the two parts of the shell are bonded together by its own viscosity, and then cured at room temperature to complete the packaging of the electrode assembly.

[0045] However, the inventors found that conventional bundling tape would increase the side thickness of the electrode assembly. During the side sealing and final sealing processes, the side of the electrode assembly would easily come into contact with the inner wall of the shell due to the increased thickness of the tape, thus affecting the packaging process. On the other hand, the glue on the tape would melt due to the heat sealing of the shell, thus affecting the heat sealing effect and reducing the product production yield.

[0046] In view of this, the utility model provides a technical solution, in which no rubber coating layer is arranged between the tightening band and the two side surfaces of the electrode assembly in the second direction, which can reduce the width of the electrode assembly in the second direction, improve the technical problem that the electrode assembly is easily in contact with the inner wall of the shell, and improve the product production yield.

[0047] See also Figures 1 to 19 The utility model provides a soft-pack battery 100 , including a shell 110 , an electrode assembly 120 and a plurality of tightening bands 140 .

[0048] See also Figure 1 to Figure 2The shell 110 is provided with a accommodating cavity. The material of the shell 110 is not limited and may be an aluminum-plastic film or other materials used to encapsulate the electrode assembly 120. The shell 110 in this embodiment adopts an aluminum-plastic film, and the aluminum-plastic film includes an outer layer, an aluminum layer and a heat-sealing layer laminated in sequence; the outer layer may be made of nylon or PET (Polyethyleneterephthalate) material, but is not limited thereto; the aluminum layer includes a metallic aluminum material, and the aluminum layer may prevent external water vapor from penetrating into the interior of the soft-pack battery and reacting with the electrolyte; the heat-sealing layer may be made of a polypropylene material, for example, it may be PP (Polypropylene), CPP (castpolypropylene) or a modified composite of PP, but is not limited thereto; the heat-sealing layer is used to be heat-sealed and connected with another aluminum-plastic film or other positions of the heat-sealing layer of the same aluminum-plastic film.

[0049] See also Figure 2 The housing 110 includes a first housing 111 and a second housing 112 that are arranged opposite to each other, and the accommodating cavity includes a first groove 113 and a second groove 114 that are arranged opposite to each other. The first groove 113 is located in the first housing 111, and the second groove 114 is located in the second housing 112. A first flange 115 extends outward from the edge of the first groove 113, and a second flange 116 extends outward from the edge of the second groove 114. The first flange 115 and the second flange 116 are arranged opposite to each other and fixedly connected. In one embodiment, the first housing 111 and the second housing 112 are arranged opposite to each other. The first shell 111 and the second shell 112 are separately arranged, and the heat sealing layer of the first flange 115 is sealed and connected with the heat sealing layer of the second flange 116 to form a shell 110 that wraps the electrode assembly 120; in another embodiment, the first shell 111 and the second shell 112 are an integral structure, that is, the first shell 111 and the second shell 112 are folded or folded in half to form a symmetrical shell 110, and then the heat sealing layer of the first flange 115 is sealed and connected with the heat sealing layer of the second flange 116 to form a shell 110 that wraps the electrode assembly 120.

[0050] The electrode assembly 120 is accommodated in the accommodation cavity. The electrode assembly 120 has a first side surface 123 and a second side surface 124 opposite to each other in the first direction. The electrode assembly 120 has a third side surface 125 and a fourth side surface 126 opposite to each other in the second direction. Figure 3 The X direction shown in the figure, and the second direction as Figure 3 The Y direction shown in the figure, the first direction, the second direction and the third direction are perpendicular to each other; the electrode assembly 120 is mainly formed by winding or stacking the electrode sheet 121 and the diaphragm 122, as shown in the figure. Figure 6 to Figure 7 and Fig. 9 The electrode assembly 120 is wound, such as Figure 13 to Figure 14 and Fig.16The electrode assembly 120 is formed by stacking. Specifically, the electrode sheet 121 includes a positive electrode sheet 121 and a negative electrode sheet 121. The positive electrode sheet 121 may include a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector. The positive current collector includes a positive current collector and a positive electrode tab 127 connected to the positive current collector. The positive current collector is coated with the positive active material layer, and the positive electrode tab 127 is not coated with the positive active material layer. Taking a lithium-ion battery as an example, the material of the positive current collector may be aluminum, and the positive active material layer includes a positive active material. The positive active material may be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganate. The above-mentioned negative electrode sheet 121 may include a negative current collector and a negative active material layer, the negative active material layer is coated on the surface of the negative current collector; the negative current collector includes a negative current collector and a negative electrode tab 128 connected to the negative current collector, the negative current collector is coated with the negative active material layer, and the negative electrode tab 128 is not coated with the negative active material layer. The material of the negative current collector may be copper, the negative active material layer includes a negative active material, and the negative active material may be carbon or silicon, etc. The material of the separator may be PP (polypropylene) or PE (polyethylene, polyethylene), etc.

[0051] In order to increase the structural stability and energy density of the soft-pack battery and facilitate battery manufacturing and assembly, the electrode assembly 120 is usually bundled with tape in the circumferential direction. Considering that the conventional bundling tape will increase the side thickness of the electrode assembly 120, the problem of increased tape thickness during side sealing and final sealing, which will affect the packaging performance of the electrode assembly 120 and reduce the product production yield, in this embodiment, a plurality of tightening belts 140 are arranged in the circumferential direction of the electrode assembly 120, and the plurality of tightening belts 140 are arranged along the third direction of the electrode assembly 120. The third direction is as shown in FIG. Figure 3 In the Z direction shown in , the number and spacing of the tightening bands 140 are not limited, and are adaptively designed according to the length of the electrode assembly 120 in the third direction and the width of the tightening bands 140, so that the tightening bands 140 can achieve a tightening effect without affecting heat dissipation.

[0052] The material of the tightening band 140 is not limited, and fiber tape, polyester film (PET), polyimide film (PI) or other materials with good adhesion, alkali resistance, tensile strength and deformation resistance can be used, depending on the requirements of the battery and the working environment and other conditions. In this embodiment, the tightening band 140 is made of polyester film (PET). In actual processing, the glue is evenly sprayed on the specified position of the PET substrate by a glue spraying device, and then a tape with a specified glue width is scraped out by a scraper. The tightening band 140 is axially wound around the electrode assembly 120 for tightening. One end of the tightening band 140 is attached to the first side 123 or the second side 124, and the other end of the tightening band 140 bypasses the third side 125 and / or the fourth side 126 and is attached to the corresponding second side 124 or first side 123; for example, one end of the tightening band 140 is attached to the first side 123, and the other end bypasses the third side 125 and the fourth side 126 and is attached to the first side 123. Figure 6 to Figure 7 and Figure 13 to Figure 14 As shown, one end of the tightening belt 140 is attached to the second side surface 124, and the other end is attached to the second side surface 124 after passing through the third side surface 125 and the fourth side surface 126; the tightening belt 140 can also be attached to the first side surface 123 at one end, and the other end is attached to the second side surface 124 after passing through the third side surface 125; or one end is attached to the first side surface 123, and the other end is attached to the second side surface 124 after passing through the fourth side surface 126, as shown. Fig. 9 and Fig.16 As shown, a rubber coating layer 130 is disposed between the tightening belt 140 and the first side surface 123 and / or the second side surface 124 .

[0053] In an example of the soft pack battery 100 of the present invention, please refer to Figures 3 to 7 and Figures 10 to 14 The tightening belt 140 includes a starting area 141, a middle area 142 and a terminal area 143 which are arranged in sequence. The starting area 141 is the area where the tightening belt 140 is attached to the first side surface from which the winding is started. The terminal area 143 is the area where the tightening belt 140 is attached to the last side surface from which the winding is started. The middle area 142 is the portion between the starting area 141 and the terminal area 143. In this embodiment, the starting area 141 is located on one of the first side surface 123 and the second side surface 124, that is, the tightening belt 140 can be wound from the first side surface 123 or the second side surface 124. The terminal area 143 is located on the same side as the starting area 141. The middle area 142 includes a first area 1421 corresponding to the third side surface 125, a third area 1423 corresponding to the fourth side surface 126, and a second area 1422 located between the first area 1421 and the third area 1423. The second area 1422 corresponds to the other of the first side surface 123 and the second side surface 124.

[0054] Specifically, in one embodiment, the tightening belt 140 is wound from the first side surface 123, and the starting area 141 is located on the first side surface 123. The tightening belt 140 continues to go around the third side surface 125, the second side surface 124 and the fourth side surface 126 and then returns to the first side surface 123, and the terminal area 143 is also located on the first side surface 123. The middle area 142 includes a first area 1421 corresponding to the third side surface 125, a second area 1422 corresponding to the second side surface 124, and a third area 1423 corresponding to the fourth side surface 126. Figures 3 to 7 and Figures 10 to 14 In another example, the tightening band 140 starts from the second side 124, and the starting area 141 is located on the second side 124. The tightening band 140 continues to go around the fourth side 126, the second side 124 and the third side 125 and then returns to the second side 124, then the terminal area 143 is also located on the second side 124, and the middle area 142 includes a first area 1421 corresponding to the third side 125 and a third area 1423 corresponding to the fourth side 126. In order to ensure that the tightening belt 140 has a tightening effect on the electrode assembly 120, a rubber coating layer 130 is arranged between the starting area 141 and the terminal area 143 and the electrode assembly 120, that is, a rubber coating layer 130 is arranged between the starting area 141 and the electrode assembly 120, and between the terminal area 143 and the electrode assembly 120. This arrangement does not increase the length of the electrode assembly 120 in the first direction, improves the problem caused by the increase in tape thickness during side sealing and final sealing, reduces the probability of the side of the electrode assembly 120 contacting the inner wall of the shell 110, and improves the packaging performance of the electrode assembly 120 and the product production yield.

[0055] In order to improve the viscosity and tightening effect of the tightening band 140, in an example of the soft-pack battery 100 of the present invention, a glue layer 130 is arranged between the second area 1422 and the electrode assembly 120, that is, glue is applied between the second area 1422 and the second side 124 or between the second area 1422 and the first side 123 to fix the second area 1422 of the tightening band 140 to the electrode assembly 120.

[0056] In another example of the soft pack battery 100 of the present invention, please refer to Figures 8 to 9 and Figures 15 to 17The tightening belt 140 includes a starting area 141, a middle area 142 and a terminal area 143 which are arranged in sequence. Similarly, the starting area 141 is the area where the tightening belt 140 is attached to the first side surface from which the winding is started, the terminal area 143 is the area where the tightening belt 140 is attached to the last side surface from which the winding is started, and the middle area 142 is the portion between the starting area 141 and the terminal area 143. The starting area 141 is located on one of the first side surface 123 and the second side surface 124, that is, the tightening belt 140 can be wound from the first side surface 123 or the second side surface 124, the terminal area 143 is located on the other of the first side surface 123 and the second side surface 124, and the middle area 142 is arranged corresponding to the third side surface 125 or the fourth side surface 126.

[0057] Specifically, a plurality of tightening bands 140 arranged along the third direction are provided on both sides of the second direction of the electrode assembly 120. In this embodiment, on the first side of the second direction of the electrode assembly 120, the tightening band 140 is wound from the first side surface 123, and the starting end area 141 is located on the first side surface 123. The tightening band 140 continues to go around the third side surface 125 and is attached to the second side surface 124. The terminal area 143 is located on the second side surface 124, and the middle area 142 corresponds to the third side surface 125. On the other side of the second direction of the electrode assembly 120, the tightening band 140 is wound from the first side surface 123, and continues to go around the fourth side surface 126 and is attached to the second side surface 124. The middle area 142 corresponds to the fourth side surface 126. Please refer to Figures 8 to 9 and Figures 15 to 17 In another embodiment, on the first side of the second direction of the electrode assembly 120, the tightening band 140 starts from the second side 124, and the starting area 141 is located on the second side 124. The tightening band 140 continues to go around the fourth side 126 and is attached to the first side 123. The middle area 142 corresponds to the fourth side 126. On the other side of the second direction of the electrode assembly 120, the tightening band 140 starts from the second side 124, continues to go around the third side 125 and is attached to the first side 123. The middle area 142 corresponds to the third side 125. In order to ensure that the tightening belt 140 has a tightening effect on the electrode assembly 120, a rubber coating layer 130 is arranged between the starting area 141 and the terminal area 143 and the electrode assembly 120, that is, a rubber coating layer 130 is arranged between the starting area 141 and the electrode assembly 120, and between the terminal area 143 and the electrode assembly 120. This arrangement does not increase the length of the electrode assembly 120 in the first direction, improves the problem of increased tape thickness during side sealing and final sealing, reduces the probability of contact between the side of the electrode assembly 120 and the inner wall of the shell 110, improves the packaging performance and product production yield of the electrode assembly 120, and at the same time reduces the amount of the tightening belt 140 used, reduces production costs, and is beneficial to the heat dissipation of the electrode assembly 120.

[0058] Further, in an example of the soft pack battery 100 of the present invention, please refer to Figures 8 to 9 and Figure 15 to Figure 16 The number of the multiple tightening bands 140 located on the side where the third side 125 is located is the same as the number of the multiple tightening bands 140 located on the side where the fourth side 126 is located, and their positions correspond, that is, the tightening bands 140 arranged on both sides of the second direction of the electrode assembly 120 are aligned. The tightening bands 140 arranged in this way have a simple processing technology and high production efficiency.

[0059] In another example of the soft pack battery 100 of the present invention, please refer to Fig.17 The multiple tightening bands 140 located on the side where the third side 125 is located are arranged alternately with the multiple tightening bands 140 located on the side where the fourth side 126 is located. The tightening bands 140 arranged alternately on both sides of the second direction of the electrode assembly 120 have a more balanced bundling force, thereby improving the tightening effect.

[0060] In an example of the soft pack battery 100 of the present invention, please refer to Figure 3 to Figure 4 , Figure 6 to Figure 7 and Fig. 9 The electrode assembly 120 includes a wound diaphragm 122. The end 1221 of the diaphragm 122 of the wound electrode assembly 120 is located at the first side 123 or the second side 124. The first side 123 and the second side 124 have a larger area than the third side 125 and the fourth side 126, which is convenient for processing. The tightening belt 140 covers at least part of the end 1221 to assist in compressing the diaphragm 122, thereby improving the tightening effect of the electrode assembly 120, reducing the occurrence of lithium plating, and increasing the number of cycles of the soft-pack battery.

[0061] Further, in an example of the soft-pack battery 100 of the present invention, the starting end region 141 covers at least part of the end 1221 of the diaphragm 122. When the tightening belt 140 is wound, the starting end covers the end 1221 of the diaphragm 122 and then is wound, so that a tensioning force can be applied to the diaphragm 122. Preferably, the tightening belt 140 and the diaphragm 122 are wound in the same direction, such as Figure 6 , Figure 7 and Fig. 9 As shown in the middle direction W, this arrangement is beneficial to further improve the tightening effect of the electrode assembly 120, which can reduce the occurrence of lithium plating and increase the number of cycles of the soft-pack battery.

[0062] In an example of the soft pack battery 100 of the present invention, please refer to Figures 10 to 16The electrode assembly 120 includes a diaphragm 122, which is a stacked structure formed by repeated bending. The pole pieces 121 are inserted between adjacent stacked diaphragms 122. The pole pieces 121 include a positive pole piece 121 and a negative pole piece 121 arranged in a certain order. The specific structure can refer to the common structure in the existing soft-pack battery field, which will not be repeated here. The diaphragm 122 in this embodiment includes a first end 1222 and a second end 1223. The first end 1222 is located on one of the first side surface 123 and the second side surface 124, and the second end 1223 is located on the first side surface 123 and the second side surface 124. On the other of the first side surface 123 and the second side surface 124, that is, if the first end 1222 is located on the first side surface 123, the second end 1223 is located on the second side surface 124, and if the second end 1223 is located on the first side surface 123, the first end 1222 is located on the second side surface 124, and the tightening belt 140 covers at least a portion of the first end 1222 and at least a portion of the second end 1223. Specifically, in one embodiment, the starting end area 141 covers at least a portion of the first end 1222, and the middle area 142 covers at least a portion of the second end 1223, as shown in FIG. Figures 10 to 12 As shown, in another embodiment, the starting area 141 of the tightening band 140 located on the first side surface in the first direction of the electrode assembly 120 covers at least a portion of the first end 1222, and the starting area 141 of the tightening band 140 located on the other side surface in the first direction of the electrode assembly 120 covers at least a portion of the second end 1223, so as to achieve auxiliary compression of the diaphragm 122, thereby improving the tightening effect of the electrode assembly 120, reducing the occurrence of lithium plating, and increasing the number of cycles of the soft-pack battery.

[0063] See also Fig.18 The utility model also provides a battery pack 10, the battery pack 10 includes any of the above-mentioned secondary batteries 100. In one embodiment of the battery pack 10 of the utility model, the battery pack 10 includes a box body 101, a box cover 102 and a plurality of secondary batteries 100. The plurality of secondary batteries 100 are placed in the box body 101, connected in series or in parallel, or in a mixture of series and parallel. The box cover 102 is sealed on the box body 101 to protect the plurality of secondary batteries 100. It should be noted that, in addition to the secondary battery 100 of the utility model, the battery pack 10 may also include a battery pack 10 thermal management system, a circuit board and other parts. The battery pack 10 may be a battery module, a battery pack, an energy storage cabinet, etc.; they will not be described one by one here.

[0064] See also Fig.19The utility model also provides an electronic device 1, which includes the above-mentioned battery pack 10. The working part 11 is electrically connected to the battery pack 10 to obtain power support. As an example, the electronic device 1 is a vehicle, and the vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc., but is not limited to this. The working part 11 is a vehicle body, and the battery pack 10 is arranged at the bottom of the vehicle body, and provides power support for the driving of the vehicle or the operation of electrical components in the vehicle. However, in some other embodiments, the electronic device 1 can also be a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy and an electric tool, etc. Spacecraft include airplanes, rockets, space shuttles and spacecrafts, etc.; the working part 11 can be a unit component that can obtain the power of the battery pack 10 and perform corresponding work, such as a fan blade rotation unit, a vacuum cleaner dust removal unit, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The present application embodiment does not impose any special restrictions on the above-mentioned electronic device 1.

[0065] In the soft-pack battery of the utility model, a plurality of tightening bands are arranged along the third direction of the electrode assembly, one end of the tightening band is attached to the first side or the second side, and the other end of the tightening band bypasses the third side and / or the fourth side and is attached to the corresponding second side or the first side. This arrangement can not only increase the structural stability and energy density of the soft-pack battery, but also facilitate the battery manufacturing and assembly effect; at the same time, since a glue coating layer is provided between the tightening band and the first side and / or the second side, and no glue coating layer is provided between the tightening band and the third side and the fourth side, the width of the electrode assembly in the second direction can be reduced, and the technical problem that the electrode assembly is easy to contact the inner wall of the shell can be improved, and the product production yield is improved. Therefore, the utility model effectively overcomes some practical problems in the prior art and has a high utilization value and use significance. The above embodiments only illustrate the principle and efficacy of the utility model, and are not used to limit the utility model. Anyone familiar with this technology can modify or change the above embodiments without violating the spirit and scope of the utility model. Therefore, all equivalent modifications or changes made by those having ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A soft pack battery, characterized in that: include: A housing having a receiving cavity; an electrode assembly, accommodated in the accommodation cavity, the electrode assembly having a first side surface and a second side surface opposite to each other in a first direction, and the electrode assembly having a third side surface and a fourth side surface opposite to each other in a second direction; A plurality of tightening bands are arranged along the third direction of the electrode assembly, one end of the tightening band is attached to the first side surface or the second side surface, and the other end of the tightening band goes around the third side surface and / or the fourth side surface and is attached to the corresponding second side surface or the first side surface; The first direction, the second direction and the third direction are perpendicular to each other, and a rubber coating layer is provided between the tightening belt and the first side surface and / or the second side surface.

2. The soft pack battery according to claim 1, characterized in that: The tightening band includes a starting area, a middle area and a terminal area which are arranged in sequence, the starting area is located on one of the first side surface and the second side surface, the terminal area and the starting area are located on the same side, the middle area includes a first area corresponding to the third side surface, a third area corresponding to the fourth side surface, and a second area located between the first area and the third area, the second area corresponds to the other of the first side surface and the second side surface, and the rubber coating layer is arranged between the starting area and the terminal area and the electrode assembly.

3. The soft pack battery according to claim 2, characterized in that: The glue layer is arranged between the second region and the electrode assembly.

4. The soft pack battery according to claim 1, characterized in that: The tightening band includes a starting area, a middle area and a terminal area which are arranged in sequence, and a plurality of the tightening bands arranged along the third direction are arranged on both sides of the second direction of the electrode assembly, the starting area is located on one of the first side surface and the second side surface, the terminal area is located on the other of the first side surface and the second side surface, the middle area is arranged corresponding to the third side surface or the fourth side surface, and the rubber coating layer is arranged between the starting area and the terminal area and the electrode assembly.

5. The soft pack battery according to claim 4, characterized in that: The number of the plurality of tightening belts located on the side where the third side is located is the same as the number of the plurality of tightening belts located on the side where the fourth side is located, and the positions thereof are corresponding.

6. The soft pack battery according to claim 4, characterized in that: The plurality of tightening bands located on the side where the third side is located are arranged alternately with the plurality of tightening bands located on the side where the fourth side is located.

7. The soft pack battery according to any one of claims 2 or 4, characterized in that: The electrode assembly includes a wound separator, an end of the wound separator is located at the first side or the second side, and the tightening band covers at least a portion of the end.

8. The soft pack battery according to claim 7, characterized in that: The starting region covers at least a portion of the ending portion.

9. The soft pack battery according to any one of claims 2 or 4, characterized in that: The electrode assembly includes a diaphragm, which is a stacked structure formed by repeated bending. The diaphragm includes a first end and a second end, the first end is located on one of the first side surface and the second side surface, and the second end is located on the other of the first side surface and the second side surface, and the tightening band covers at least a portion of the first end and at least a portion of the second end.

10. The soft pack battery according to claim 1, characterized in that: Along the second direction, the accommodating cavity includes a first groove and a second groove arranged opposite to each other. Along the first direction and the third direction, the edge of the first groove has a first flange extending outward, and the edge of the second groove has a second flange extending outward. The first flange and the second flange are arranged opposite to each other and fixedly connected.

11. A battery pack, characterized in that: A soft-pack battery comprising the soft-pack battery according to any one of claims 1 to 10.

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