Soft package battery and battery assembly

Abstract

The invention discloses a soft package battery and a battery assembly, and the soft package battery comprises a shell, a battery cell, a first outer tab and a second outer tab. The shell comprises a packaging main body, a top sealing edge and two side sealing edges, the packaging main body is provided with an inner cavity, and the packaging main body, the side sealing edges and the top sealing edge define a mounting cavity; the shell further comprises a first protruding part and a second protruding part which protrude towards the installation cavity, the first protruding part is provided with a first containing cavity communicated with the inner cavity, and the second protruding part is provided with a second containing cavity communicated with the inner cavity. The battery cell is positioned in the inner cavity and comprises a plurality of first inner tabs and second inner tabs; the first outer tab and the plurality of first inner tabs are welded together to form a first welding part, and at least part of the first welding part is located in the first accommodating cavity; the second outer tab and the plurality of second inner tabs are jointly welded to form a second welding part, and at least part of the second welding part is located in the second accommodating cavity, so that the space of the first welding part and the second welding part in the inner cavity is reduced, and the energy density of the soft package battery is improved.

Description

Technical Field

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

[0002] In a multi-pole battery cell, the internal tab and the external tab need to be welded together to form a welded portion, and then connected to the external device through the external tab. In order to ensure that there is sufficient welding area between the external tab and the inner tab, there is sufficient overlapping between the external tab and the inner tab. In order to increase the battery length caused by the welded portion, some technologies fold the inner tab in half so that the thickness of the welded portion corresponds to the length of the battery. However, even so, the thickness of the multi-layer inner tab and the outer tab will still increase the length of the soft-pack battery and affect the energy density of the battery. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a soft-pack battery having a higher energy density.

[0004] The present invention also provides a battery assembly having the above-mentioned soft-pack battery.

[0005] A soft-pack battery according to an embodiment of the first aspect of the present invention includes: a housing, a battery cell, a first external tab, and a second external tab.

[0006] The shell includes a packaging body, a top seal and two side seals, the packaging body has an inner cavity, the packaging body includes two side walls in the width direction of the soft-pack battery, and a top wall on one side of the length direction of the soft-pack battery, the two side seals are respectively connected to the two side walls, and are both folded toward the side walls, and the side seals protrude from the side seal portion of the top wall along the length direction of the soft-pack battery, the top seal is connected to the top wall, and the top wall, side seal portion and top seal jointly define a mounting cavity; the shell also includes a first protrusion and a second protrusion protruding toward the mounting cavity, the first protrusion A first accommodating cavity communicating with the inner cavity is formed inside the part, and a second accommodating cavity communicating with the inner cavity is formed inside the second protruding part; the battery cell includes a battery cell body, and a plurality of first inner pole ears and a plurality of second inner pole ears connected to the battery cell body, and the battery cell body is located in the inner cavity; the first outer pole ear is welded together with the plurality of first inner pole ears, and a first welding portion is formed at the welding position, and at least a portion of the first welding portion is located in the first accommodating cavity; the second outer pole ear is welded together with the plurality of second inner pole ears, and a second welding portion is formed at the welding position, and at least a portion of the second welding portion is located in the second accommodating cavity.

[0007] The soft-pack battery according to the embodiment of the present invention has at least the following beneficial effects:

[0008] In this embodiment, at least a portion of the first welding portion is located in the first accommodating cavity, and at least a portion of the second welding portion is located in the second accommodating cavity. Since both the first protrusion and the second protrusion protrude toward the mounting cavity, that is, both the first protrusion and the second protrusion are located in the mounting cavity, there is no need to occupy additional external space of the soft-pack battery, thereby reducing the overall size of the soft-pack battery and thereby improving the energy density of the soft-pack battery of this embodiment.

[0009] According to some embodiments of the present invention, the first protrusion is located on the top wall, and the connection between the top seal and the top wall is defined as the first connection. The first inner tab is bent along its own thickness direction to form a first connection portion extending along the thickness direction of the battery cell. The first outer tab includes a second connection portion, and the second connection portion is welded together with a plurality of the first connection portions to form a first welding portion.

[0010] The first accommodating cavity extends to the first connection, the first welding portion is located in the first accommodating cavity and extends to the first connection along the thickness direction of the battery core; or,

[0011] In the thickness direction of the soft-pack battery, the first accommodating cavity is spaced apart from the first connection point, the second connection portion is located on the side of each first connection portion facing the battery cell body, and each first connection portion is located in the accommodating cavity.

[0012] According to some embodiments of the present invention, the second protrusion is located on the top wall, and the connection between the top seal and the top wall is defined as the first connection. The second inner tab is bent along its own thickness direction to form a third connection portion extending along the thickness direction of the battery cell. The second outer tab includes a fourth connection portion, and the fourth connection portion is welded together with a plurality of the third connection portions to form a second welding portion.

[0013] The second accommodating cavity extends to the first connection, the second welding portion is located in the second accommodating cavity and extends to the first connection along the thickness direction of the battery core; or,

[0014] In the thickness direction of the soft-pack battery, the second accommodating cavity is spaced apart from the first connection point, the fourth connecting portion is located on the side of each of the third connecting portions facing the battery cell body, and each of the third connecting portions is located in the accommodating cavity.

[0015] According to some embodiments of the present invention, the first protrusion and the second protrusion are both located on the side sealing portion, and a first channel connecting the first accommodating cavity and the inner cavity, and a second channel connecting the second accommodating cavity and the inner cavity are formed inside the shell, the first inner pole ear extends to the first accommodating cavity through the first channel, and the second inner pole ear extends to the second accommodating cavity through the second channel.

[0016] According to some embodiments of the present invention, the battery cell is a laminated battery cell, the battery cell body includes a plurality of stacked first and second pole pieces, and a separator provided between the first and second pole pieces, the first inner pole piece is connected to the first pole piece, and extends from one side of two adjacent layers of the separator in the width direction of the soft-pack battery, and the second inner pole piece is connected to the second pole piece, and extends from the other side of the two adjacent layers of the separator in the width direction of the soft-pack battery;

[0017] The isolation film has a first edge and a second edge opposite to each other in the length direction of the soft-pack battery, and the first welding portion and the second welding portion are both located between the first edge and the second edge.

[0018] According to some embodiments of the present invention, the top sealing edge has a third protruding portion protruding toward the installation cavity, and the first channel is formed inside the third protruding portion; and / or,

[0019] The top sealing edge has a fourth protruding portion protruding toward the installation cavity, and the second channel is formed inside the fourth protruding portion.

[0020] According to some embodiments of the present invention, the first protrusion and the second protrusion are both located at the top sealing edge.

[0021] According to some embodiments of the present invention, the first welding portion includes a plurality of first bending portions formed by bending, and the first bending portions are arched along the thickness direction of the first welding portion itself; and / or,

[0022] The second welding portion includes a plurality of second bending portions formed by bending, and the second bending portions are arched along the thickness direction of the second welding portion itself.

[0023] According to the second embodiment of the present invention, the battery assembly includes a PCB board and the soft-pack battery described in the first embodiment, and the PCB board is arranged in the installation cavity.

[0024] The battery assembly according to the embodiment of the present invention has at least the following beneficial effects:

[0025] In the soft-pack battery of the first embodiment, at least part of the first welding portion in the soft-pack battery is located in the first accommodating cavity, and at least part of the second welding portion is located in the second accommodating cavity. Moreover, since both the first protrusion and the second protrusion protrude toward the mounting cavity, that is, both the first protrusion and the second protrusion are located in the mounting cavity, there is no need to occupy additional external space of the soft-pack battery, thereby reducing the overall size of the soft-pack battery and thereby improving the energy density of the soft-pack battery of this embodiment.

[0026] According to some embodiments of the present invention, the first protrusion and the second protrusion are both located on the top wall, and in the width direction of the soft-pack battery, the first protrusion and the second protrusion are spaced apart to form a third accommodating cavity;

[0027] The PCB board includes a board body and several components. The components are provided on the side of the board body facing the top wall. The components include a first component having the largest dimension in the length direction of the soft-pack battery. At least a portion of the first component is located in the third accommodating cavity.

[0028] According to some embodiments of the present invention, the first protrusion and the second protrusion are both located on the top edge, the edge of the PCB board has a first avoidance groove and a second avoidance groove, at least a portion of the first protrusion is located in the first avoidance groove, and at least a portion of the second protrusion is located in the second avoidance groove.

[0029] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0031] Figure 1 This is a schematic structural diagram of a first soft-pack battery according to an embodiment of the first aspect of the present invention;

[0032] Figure 2 for Figure 1 sectional view of

[0033] Figure 3 for Figure 2 Magnified view of area A in the middle;

[0034] Figure 4 This is a schematic structural diagram of a second soft-pack battery according to an embodiment of the first aspect of the invention;

[0035] Figure 5 for Figure 4 sectional view of

[0036] Figure 6 for Figure 5 Magnified view of area B in the middle;

[0037] Figure 7 A partial cross-sectional view of a third soft-pack battery according to an embodiment of the first aspect of the invention;

[0038] Figure 8 for Figure 7 Magnified view of area C in the middle;

[0039] Figure 9 This is a schematic structural diagram of a fourth soft-pack battery according to an embodiment of the first aspect of the present invention;

[0040] Figure 10 for Figure 9 Enlarged schematic diagram of region D in the middle;

[0041] Figure 11 for Figure 10 Schematic diagram of the structure of the battery cell in the medium soft pack battery;

[0042] Figure 12 This is a schematic structural diagram of a fifth soft-pack battery according to an embodiment of the first aspect of the present invention;

[0043] Figure 13 for Figure 12 Magnified view of area E in the middle;

[0044] Figure 14 This is a schematic structural diagram of a sixth soft-pack battery according to an embodiment of the first aspect of the present invention;

[0045] Figure 15 This is a partial cross-sectional view of the seventh soft-pack battery according to the first embodiment of the present invention.

[0046] Reference numerals:

[0047] Housing 100, package body 110, inner cavity 111, top wall 112, side wall 113, top sealing edge 120, third protruding portion 121, side sealing edge 130, side sealing portion 131, first protruding portion 140, first accommodating cavity 141, second protruding portion 150, mounting cavity 160, first connection point 170;

[0048] Battery cell 200, battery cell body 210, first pole piece 211, second pole piece 212, isolation film 213, first edge 2131, second edge 2132, first inner tab 220, first connecting portion 221, second inner tab 230;

[0049] A first external tab 300, a second connecting portion 310, and a fifth connecting portion 320;

[0050] a second outer tab 400;

[0051] First welding portion 500 and bending portion 510 . DETAILED DESCRIPTION

[0052] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0053] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0054] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0055] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0056] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0057] In a multi-pole battery cell, the internal tab and the external tab need to be welded together to form a welded portion, and then connected to the external device through the external tab. In order to ensure that there is sufficient welding area between the external tab and the inner tab, there is sufficient overlapping between the external tab and the inner tab. In order to increase the battery length caused by the welded portion, some technologies fold the inner tab in half so that the thickness of the welded portion corresponds to the length of the battery. However, even so, the thickness of the multi-layer inner tab and the outer tab will still increase the length of the soft-pack battery and affect the energy density of the battery.

[0058] In view of the above background, Figures 1 to 15 The present invention proposes a soft pack battery with a higher energy density. It should be noted that in order to avoid the appearance of dense lines in the figure and the unclearness of the figure, some of the cross-section lines in the figure are not shown. Figure 3 、 Figure 6 、 Figure 7 and Figure 15 The outlines between the first connecting parts 221 are not shown. The specific details of the first connecting parts 221 are as follows. Figure 8 shown.

[0059] Reference Figures 1 to 3 、 Figure 9 and Figure 14 As shown, the soft-pack battery according to the first embodiment of the present invention includes: a shell 100, a battery cell 200, a first external tab 300 and a second external tab 400.

[0060] The housing 100 may be a soft film such as an aluminum plastic film or a steel plastic film, and the housing 100 includes a housing body 110, a top sealing edge 120, and two side sealing edges 130 (such as Figure 1 As shown). The soft-pack battery has a set width and length, and the package body 110 has an inner cavity 111. The package body 110 includes two side walls 113 in the width direction of the soft-pack battery, and a top wall 112 on one side in the length direction of the soft-pack battery. The two side seals 130 are respectively connected to the two side walls 113 and are both folded toward the side walls 113. The side seals 130 protrude from the top wall 112 along the length direction of the soft-pack battery. The portion of the side seal 130 protruding from the top wall 112 along the length direction of the soft-pack battery is the side seal portion 131. The top seal 120 is connected to the top wall 112, and the top seal 120 extends along the width direction of the soft-pack battery and is connected to the side seal portion 131. The top wall 112, the side seal portion 131 and the top seal 120 together define a mounting cavity 160, which is used to accommodate a PCB board, for example.

[0061] The housing 100 further includes a first protruding portion 140 and a second protruding portion 150 protruding toward the mounting cavity 160. A first accommodating cavity 141 (eg, a first accommodating cavity 141 communicating with the inner cavity 111) is formed inside the first protruding portion 140. Figure 3As shown), a second accommodating cavity communicating with the inner cavity 111 is formed inside the second protrusion 150, and the first protrusion 140 and the second protrusion 150 are, for example, located on the top wall 112 (as shown Figure 1 As shown), top sealing edge 120 (as shown Figure 14 As shown) or side seal portion 131 (as shown Figure 9 and 10 As shown). Exemplarily, the housing 100 is formed by processing an aluminum-plastic film, which includes a nylon layer, an aluminum layer, and a PP layer (polypropylene layer). The first protrusion 140 is located on the top wall 112. During the processing of the housing 100, the PP layer is punched toward the nylon layer at the position of the top wall 112 to form the first protrusion 140 and the first accommodating cavity 141. Taking the first protrusion 140 located on the side seal portion 131 as an example, a first channel is formed inside the housing 100 to connect the first accommodating cavity 141 and the inner cavity 111, and the first inner tab 220 extends to the first accommodating cavity 141 through the first channel. It can be seen that the top seal 120 is formed by bonding two layers of aluminum-plastic film. During the processing, the PP layer is punched toward the nylon layer in at least one of the two layers of aluminum-plastic film forming the top seal 120 to form the first protrusion 140 and the first accommodating cavity 141. Similarly, the second protrusion 150 is disposed on the top wall 112 or the top sealing edge 120. The second protrusion 150 is located on the side sealing portion 131. A second passage is formed within the housing 100, connecting the second accommodating cavity and the inner cavity 111. The second inner tab 230 extends into the second accommodating cavity through the second passage. The second protrusion 150 is similarly configured and will not be further described here.

[0062] The battery cell 200 is, for example, a wound battery cell or a laminated battery cell. The battery cell 200 includes a battery cell body 210, and a plurality of first inner tabs 220 and a plurality of second inner tabs 230 connected to the battery cell body 210. The battery cell body 210 is located in the inner cavity 111. The first outer tab 300 is welded to the plurality of first inner tabs 220, and a first welding portion 500 (such as Figure 3 As shown), the first welding portion 500 is at least partially located in the first accommodating cavity 141. The second outer pole ear 400 is welded together with the plurality of second inner pole ears 230 to form a second welding portion at the welding position, and at least a portion of the second welding portion is located in the second accommodating cavity. Exemplarily, the battery cell body 210 includes an anode sheet, a cathode sheet, and an isolation membrane 213 located between the anode sheet and the cathode sheet. The first inner pole ear 220 is connected to the anode sheet, and correspondingly, the second inner pole ear 230 is connected to the cathode sheet. The first inner pole ear is connected to the current collector of the anode sheet, for example, by welding, or is an integral structure with the current collector of the anode sheet. Similarly, the second inner pole ear 230 is connected to the current collector of the cathode sheet, for example, by welding, or is an integral structure with the current collector of the cathode sheet.

[0063] Specifically, in this embodiment, at least a portion of the first welding portion 500 is located in the first accommodating cavity 141, and at least a portion of the second welding portion is located in the second accommodating cavity. Moreover, since the first protrusion 140 and the second protrusion 150 both protrude toward the mounting cavity 160, that is, the first protrusion 140 and the second protrusion 150 are both located in the mounting cavity 160, there is no need to occupy additional external space of the soft-pack battery, thereby reducing the overall size of the soft-pack battery and thereby improving the energy density of the soft-pack battery of this embodiment.

[0064] Furthermore, because the first protrusion 140 and the second protrusion 150 are located outside the inner cavity 111, when the battery of this embodiment is connected to the PCB to form a battery pack, the PCB mounting position, the PCB shape, and the position of the components can be adaptively adjusted to match the position and size of the first protrusion 140 and the second protrusion 150. This allows the PCB to partially overlap with the space occupied by the first protrusion 140 and the second protrusion 150 in the length, width, or thickness direction of the soft-pack battery, thereby improving the overall energy density of the battery assembly. For example, in some embodiments, the first protrusion 140 and the second protrusion 150 are both located on the top wall 112. The first protrusion 140 and the second protrusion 150 are spaced apart in the width direction of the soft-pack battery to form a third accommodating cavity. The PCB includes a body and several components. The side of the body facing the top wall 112 has components, including a first component that has the largest dimension in the length direction of the soft-pack battery. At least a portion of the first component is located in the third accommodating cavity. That is, the space occupied by the first component and the first protrusion 140 and the second protrusion 150 in the length direction of the soft-pack battery at least partially overlaps, thereby reducing the size of the battery assembly in the length direction of the soft-pack battery and improving the energy density of the battery assembly. Alternatively, in some embodiments, the first protrusion 140 and the second protrusion 150 are both located on the top seal 120, and the edge of the PCB board has a first avoidance groove and a second avoidance groove, with at least a portion of the first protrusion 140 located in the first avoidance groove and at least a portion of the second protrusion 150 located in the second avoidance groove, thereby reducing the size of the battery assembly in the thickness direction of the soft-pack battery and thereby improving the energy density of the battery assembly.

[0065] It should be noted that, in this embodiment, the shell includes a first protrusion 140 and a second protrusion 150, which cannot be interpreted as the shell 100 in this application having only the first protrusion 140 and the second protrusion 150. For example, in some embodiments, the shell 100 also includes a third protrusion and a fourth protrusion, and the third protrusion has a third accommodating cavity connected to the inner cavity 111, and the fourth protrusion has a fourth accommodating cavity connected to the inner cavity 111. Correspondingly, the battery cell 200 also includes a third inner pole ear and a fourth inner pole ear, and the soft-pack battery also includes a third outer pole ear and a fourth outer pole ear. The third inner pole ear and the third outer pole ear are welded to form a third welding portion, and the fourth inner pole ear and the fourth outer pole ear are welded to form a fourth welding portion. The third welding portion is at least partially located in the third accommodating cavity, and the fourth welding portion is at least partially located in the fourth accommodating cavity. That is, as long as the number of protrusions (collectively referred to as the first protrusion to the Nth protrusion) is the same as the number of external pole ears (collectively referred to as the first external pole ear, the second external pole ear to the Nth external pole ear), the formed welding parts (collectively referred to as the first welding part to the Nth welding part) all have accommodating cavities (collectively referred to as the first accommodating cavities to the Nth accommodating cavities) to adapt to them.

[0066] Reference Figures 1 to 3 Based on the above embodiment, the first protrusion 140 is located on the top wall 112, and the connection between the top sealing edge 120 and the top wall 112 is defined as the first connection 170. The first inner tab 220 is bent along its own thickness direction to form a first connection portion 221 extending along the thickness direction of the battery cell 200. The first outer tab 300 includes a second connection portion 310. The second connection portion 310 and the multiple first connection portions 221 are welded together to form a first welding portion 500. The first accommodating cavity 141 extends to the first connection 170. The first welding portion 500 is located in the first accommodating cavity 141 and extends to the first connection 170 along the thickness direction of the battery cell 200, thereby avoiding the welding portion from occupying additional space, further improving the compactness of the internal structure of the battery, and thereby improving the energy density of the battery.

[0067] Reference Figures 4 to 6 In some embodiments, the first protrusion 140 is located on the top wall 112, and the connection between the top seal 120 and the top wall 112 is defined as the first connection 170. The first inner tab 220 is bent along its own thickness direction to form a first connection portion 221 extending along the thickness direction of the battery cell 200. The first outer tab 300 includes a second connection portion 310, which is welded together with the plurality of first connection portions 221 to form a first welded portion 500. In the thickness direction of the soft-pack battery, the first accommodating cavity 141 is spaced apart from the first connection 170, that is, the first accommodating cavity 141 does not extend to the first connection 170, thereby not reducing the sealing width of the top seal 120 at this location. As a result, this embodiment improves the energy density of the soft-pack battery without affecting the sealing performance of the soft-pack battery.

[0068] Reference Figure 7 and Figure 8 In some embodiments, the first protrusion 140 is located on the top wall 112, and the connection between the top sealing edge 120 and the top wall 112 is defined as the first connection 170. The first inner tab 220 is bent along its own thickness direction to form a first connection portion 221 extending along the thickness direction of the battery cell 200. The first outer tab 300 includes a second connection portion 310. The second connection portion 310 and the multiple first connection portions 221 are welded together to form a first welding portion 500. The second connection portion 310 is located on the side of each first connection portion 221 facing away from the battery cell body 210. The first outer tab 300 is bent toward the battery cell body 210 and extends out of the first accommodating cavity 141, that is, the first outer tab 300 has a fifth connection portion 320 extending along the length direction of the soft-pack battery. One end of the fifth connection portion 320 is located in the first accommodating cavity 141 and connected to the second connection portion 310, and the other end extends out of the first accommodating cavity 141. Furthermore, the end faces of each first connection portion 221 facing the first connection point 170 are welded to the fifth connection portion 320, which not only increases the connection area between the first outer pole ear 300 and the first inner pole ear 220, but also enables each first inner pole ear 220 to directly contact the fifth connection portion 320 of the first outer pole ear 300, thereby effectively dispersing the current density, reducing the temperature of the first inner pole ear 220 directly connected to the first outer pole ear 300, reducing heat loss, improving the overall thermal stability of the battery, and extending the battery life.

[0069] Similarly, in some embodiments, the second protrusion 150 is located on the top wall 112, and the connection between the top sealing edge 120 and the top wall 112 is defined as the first connection 170. The second inner pole ear 230 is bent along its own thickness direction to form a third connection portion extending along the thickness direction of the battery cell 200. The second outer pole ear 400 includes a fourth connection portion, and the fourth connection portion and multiple third connection portions are welded together to form a second welding portion. The second accommodating cavity extends to the first connection 170, and the second welding portion is located in the second accommodating cavity and extends to the first connection 170 along the thickness direction of the battery cell 200; or, in the thickness direction of the soft-pack battery, the second accommodating cavity and the first connection 170 are spaced apart, and the fourth connection portion is located on the side of each third connection portion facing the battery cell body 210, and each third connection portion is located in the accommodating cavity. The principle is the same as the setting method of the first accommodating cavity 141 and the first welding portion 500 in the above embodiment, and will not be repeated here.

[0070] Reference Figure 11In some embodiments, the battery cell 200 is a laminated battery cell 200, and the battery cell body 210 includes a plurality of stacked first and second electrode sheets 211, 212, and a separator 213 disposed between the first and second electrode sheets 211, 212. For example, the first electrode sheet 211 is the cathode sheet of the battery cell 200, and the second electrode sheet 212 is the anode sheet of the battery cell 200. A first inner tab 220 is connected to the first electrode sheet 211 and extends from one side of the two adjacent layers of separator 213 in the width direction of the soft-pack battery. A second inner tab 230 is connected to the second electrode sheet 212 and extends from the other side of the two adjacent layers of separator 213 in the width direction of the soft-pack battery. Along the length direction of the soft-pack battery, the separator 213 has opposing first and second edges 2131, 2132. The first weld 500 and the second weld are both located between the first and second edges 2131, 2132.

[0071] Specifically, it can be known that during the processing of the soft-pack battery, the tab welding position needs to be set outside the coverage of the isolation film 213 to ensure welding accuracy and strength and avoid damage to the isolation film 213 during the welding process. As in the conventional technology, in order to reduce the damage to the isolation film 213 caused by high temperature, the tab welding position needs to be set outside the isolation film 213. If the welding position is set on the top of the battery cell 200, an additional space for accommodating the welding position is required, resulting in an increase in the volume of the soft-pack battery and a reduction in the energy density of the soft-pack battery. The present embodiment can effectively improve this problem. In the present embodiment, the battery cell is a laminated battery cell 200, and the first inner tab 220 and the second inner tab 230 both extend from the adjacent isolation film 213 in the width direction of the soft-pack battery, and the first welding portion 500 and the second welding portion are both located between the first edge 2131 and the second edge 2132 of the isolation film 213. As a result, the length of the soft-pack battery is reduced because the space occupied by the first and second welds 500 and 213 in the lengthwise direction of the soft-pack battery overlaps with the separator 213. Regarding the width of the soft-pack battery, the first and second welds 500 and 212 are folded toward the package body 110 along with the side seal 130 and protrude into the mounting cavity 160, eliminating the need for additional space in the widthwise direction of the soft-pack battery. Consequently, within the same volume, larger first and second electrode sheets 211 and 212 can be accommodated, resulting in a higher energy density.

[0072] Reference Figure 12 and Figure 13In some embodiments, the top seal 120 includes a third protrusion 121 that protrudes toward the mounting cavity 160, and a first channel is formed within the third protrusion 121. Specifically, in this embodiment, the first protrusion 140 is located on the side seal 131. Therefore, a channel needs to be formed in the side seal 130 or the top seal 120 to communicate with the first accommodating cavity 141 within the first protrusion 140. In other words, a portion of the first inner tab 220 is enclosed within the top seal 120 or the side seal 130. It can be seen that since the first inner tab 220 itself has a certain thickness, the location of the first inner tab 220 in the side seal 130 or the top seal 120 will increase the thickness of the side seal 130 or the top seal 120. Based on this, this embodiment forms the second channel within the third protrusion 121 of the top seal 120. The third protrusion 121 protrudes toward the mounting cavity 160, thereby eliminating the need to occupy additional space outside the soft-pack battery and improving the energy density of the soft-pack battery. Similarly, in some embodiments, the top seal 120 also includes a fourth protrusion, within which the second channel is formed, which will not be further described here.

[0073] Reference Figure 15 In some embodiments, the first welding portion 500 includes a plurality of first bends 510 formed by bending, and the first bends 510 are arched along the thickness direction of the first welding portion 500 itself. It is understood that in order to ensure the resistance to current transmission between the first inner tab 220 and the first outer tab 300, as well as the connection reliability between the first inner tab 220 and the first outer tab 300, it is necessary to ensure a sufficient welding area between the first inner tab 220 and the first outer tab 300. In other words, the first welding portion 500 has a certain length, and the corresponding first accommodating cavity 141 has a larger size. For example, the first accommodating cavity 141 is located on the top wall 112, that is, the first accommodating cavity 141 needs to be larger in the thickness direction of the soft-pack battery to accommodate the first welding portion 500. However, for some ultra-thin soft-pack batteries, the thickness direction is limited. The use of a bending design can effectively reduce the space occupied by the first welding portion 500 in the thickness direction, thereby optimizing the overall structure of the soft-pack battery while ensuring the welding area, further improving the energy density. By optimizing the bending design of the welding part, the space utilization rate of the soft-pack battery in the thickness direction is significantly improved. For example, when the first accommodating cavity 141 is located at the side sealing part 131 or the top sealing edge 120, the bending design can effectively reduce the space occupied by the first welding part 500 in the length direction of the soft-pack battery, thereby optimizing the overall structure of the soft-pack battery while ensuring the welding area, and further improving the energy density. Similarly, in some embodiments, the second welding part includes a second bending part 510 formed by a plurality of bends, and the second bending part 510 is arched along the thickness direction of the second welding part itself. No further details will be given here.

[0074] According to the second aspect of the present invention, the battery assembly includes a PCB board and the soft-pack battery of the first aspect, and the PCB board is disposed in the mounting cavity 160. Specifically, the soft-pack assembly of this embodiment adopts the soft-pack battery of the first aspect, at least a portion of the first welding portion 500 in the soft-pack battery is located in the first accommodating cavity 141, and at least a portion of the second welding portion is located in the second accommodating cavity. Moreover, since the first protrusion 140 and the second protrusion 150 both protrude toward the mounting cavity 160, that is, the first protrusion 140 and the second protrusion 150 are both located in the mounting cavity 160, without occupying additional space outside the soft-pack battery, the overall size of the soft-pack battery is reduced, and the energy density of the soft-pack battery is increased, thereby increasing the energy density of the battery assembly of this embodiment.

[0075] It should be noted that, since this embodiment adopts all the technical features of the soft-pack battery of the first embodiment, the battery assembly of this embodiment has all the beneficial effects brought by the first embodiment.

[0076] Based on the above embodiment, the first protrusion 140 and the tab 150 are both located on the top wall 112. In the width direction of the soft-pack battery, the first protrusion 140 and the second protrusion 150 are spaced apart to form a third accommodating cavity. The PCB includes a board body and a plurality of components. The board body has components on the side facing the top wall 112, including a first component having the largest dimension in the length direction of the soft-pack battery. At least a portion of the first component is located in the third accommodating cavity. That is, the space occupied by the first component and the first protrusion 140 and the second protrusion 150 in the length direction of the soft-pack battery at least partially overlaps. This reduces the size of the battery assembly in the length direction of the soft-pack battery and improves the energy density of the battery assembly. Or in some embodiments, the first protrusion 140 and the second protrusion 150 are both located on the top sealing edge 120, and the edge of the PCB board has a first air avoidance groove and a second air avoidance groove, at least a portion of the first protrusion 140 is located in the first air avoidance groove, and at least a portion of the second protrusion 150 is located in the second air avoidance groove, so as to reduce the size of the battery assembly in the thickness direction of the soft-pack battery, thereby improving the energy density of the battery assembly.

[0077] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A soft pack battery, characterized in that: include: The outer shell includes a packaging body, a top seal, and two side seals, the packaging body having an inner cavity, the packaging body including two side walls in the width direction of the soft-pack battery, and a top wall on one side in the length direction of the soft-pack battery, the two side seals are respectively connected to the two side walls and are both folded toward the side walls, and the side seals protrude from the side seal portion of the top wall along the length direction of the soft-pack battery, the top seal is connected to the top wall, and the top wall, side seal portion, and top seal jointly define a mounting cavity; and, The housing further includes a first protruding portion and a second protruding portion protruding toward the installation cavity, wherein a first accommodating cavity communicating with the inner cavity is formed inside the first protruding portion, and a second accommodating cavity communicating with the inner cavity is formed inside the second protruding portion; A battery cell, comprising a battery cell body, and a plurality of first inner tabs and a plurality of second inner tabs connected to the battery cell body, wherein the battery cell body is located in the inner cavity; A first outer tab is welded together with the first inner tabs to form a first welding portion at the welding position, wherein the first welding portion is at least partially located in the first accommodating cavity; The second outer tab is welded together with the plurality of second inner tabs to form a second welding portion at the welding position, and at least a portion of the second welding portion is located in the second accommodating cavity.

2. The soft pack battery according to claim 1, characterized in that: The first protrusion is located on the top wall, and the connection between the top sealing edge and the top wall is defined as the first connection. The first inner tab is bent along its own thickness direction to form a first connection portion extending along the thickness direction of the battery cell. The first outer tab includes a second connection portion, and the second connection portion is welded together with multiple first connection portions to form a first welding portion. The first accommodating cavity extends to the first connection, the first welding portion is located in the first accommodating cavity and extends to the first connection along the thickness direction of the battery core; or, In the thickness direction of the soft-pack battery, the first accommodating cavity is spaced apart from the first connection point, the second connection portion is located on the side of each first connection portion facing the battery cell body, and each first connection portion is located in the accommodating cavity.

3. The soft pack battery according to claim 1, characterized in that The second protrusion is located on the top wall, and the connection between the top sealing edge and the top wall is defined as the first connection. The second inner tab is bent along its own thickness direction to form a third connection portion extending along the thickness direction of the battery cell. The second outer tab includes a fourth connection portion, and the fourth connection portion is welded together with the plurality of third connection portions to form a second welding portion. The second accommodating cavity extends to the first connection, the second welding portion is located in the second accommodating cavity and extends to the first connection along the thickness direction of the battery core; or, In the thickness direction of the soft-pack battery, the second accommodating cavity is spaced apart from the first connection point, the fourth connecting portion is located on the side of each of the third connecting portions facing the battery cell body, and each of the third connecting portions is located in the accommodating cavity.

4. The soft pack battery according to claim 1, characterized in that The first protrusion and the second protrusion are both located on the side sealing portion, and a first channel connecting the first accommodating cavity and the inner cavity, and a second channel connecting the second accommodating cavity and the inner cavity are formed inside the shell. The first inner pole ear extends to the first accommodating cavity through the first channel, and the second inner pole ear extends to the second accommodating cavity through the second channel.

5. The soft pack battery according to claim 4, characterized in that: The battery cell is a laminated battery cell, wherein the battery cell body includes a plurality of stacked first and second electrode sheets, and a separator disposed between the first and second electrode sheets, the first inner electrode tab being connected to the first electrode sheet and extending from one side of two adjacent layers of the separator in the width direction of the soft-pack battery, and the second inner electrode tab being connected to the second electrode sheet and extending from the other side of two adjacent layers of the separator in the width direction of the soft-pack battery; The isolation film has a first edge and a second edge opposite to each other in the length direction of the soft-pack battery, and the first welding portion and the second welding portion are both located between the first edge and the second edge.

6. The soft pack battery according to claim 5, characterized in that: The top sealing edge has a third protruding portion protruding toward the installation cavity, and the first channel is formed inside the third protruding portion; and / or, The top sealing edge has a fourth protruding portion protruding toward the installation cavity, and the second channel is formed inside the fourth protruding portion.

7. The soft pack battery according to claim 1, characterized in that: The first protrusion and the second protrusion are both located on the top sealing edge.

8. The soft pack battery according to any one of claims 1 to 7, characterized in that: The first welding portion includes a plurality of first bending portions formed by bending, and the first bending portions are arched along the thickness direction of the first welding portion itself; and / or, The second welding portion includes a plurality of second bending portions formed by bending, and the second bending portions are arched along the thickness direction of the second welding portion itself.

9. A battery assembly, characterized in that include: The soft pack battery according to any one of claims 1 to 8; The PCB board is arranged in the installation cavity.

10. The battery assembly according to claim 9, characterized in that The first protrusion and the second protrusion are both located on the top wall. In the width direction of the soft-pack battery, the first protrusion and the second protrusion are spaced apart to form a third accommodating cavity; The PCB board includes a board body and several components. The components are provided on the side of the board body facing the top wall. The components include a first component having the largest dimension in the length direction of the soft-pack battery. At least a portion of the first component is located in the third accommodating cavity.

11. The battery assembly according to claim 9, characterized in that The first protrusion and the second protrusion are both located on the top sealing edge, and the edge of the PCB board has a first avoidance groove and a second avoidance groove, at least part of the first protrusion is located in the first avoidance groove, and at least part of the second protrusion is located in the second avoidance groove.

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