Soft package battery

Abstract

The utility model provides a soft package battery which comprises a shell and a battery cell, the shell comprises two half shells which are oppositely arranged, at least one half shell is provided with a punching pit, and the punching pit comprises two side surfaces which are oppositely arranged and a bottom surface which is connected with the two side surfaces; the battery cell is located in the punching pit and comprises a plurality of negative plates, a plurality of positive plates and diaphragms, the diaphragms are folded in a Z shape to form a plurality of insertion spaces, and the negative plates and the positive plates are sequentially and alternately inserted into the insertion spaces in the first direction; the layer, close to the bottom face, of the diaphragm in the first direction is a first surface, the first surface extends outwards to form a free section, the free section is bent in the first direction and extends to the side face, and in the first direction, the size of the free section is smaller than the depth of the punching pit, so that the free section is completely located in the punching pit and wrapped by the side face of the punching pit. And even if the free section is warped or folded, the free section cannot extend out of the punching pit, so that the free section cannot influence the hot-melting sealing process, and the sealing quality is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to a soft package battery. BACKGROUND

[0002] Soft package batteries are widely used in mobile phones, electronic wear, notebook computers and other digital products, electric tools and electric vehicles due to their advantages of good safety performance, light weight, large capacity and flexible design. The packaging shell of the soft package battery is an important part of the battery and has a great influence on the size of the battery. CONTENT OF THE UTILITY MODEL

[0003] Therefore, the present application aims to provide a soft package battery to solve or partially solve the problems in the background art.

[0004] To achieve the above purpose, the present application provides a soft package battery, comprising:

[0005] A shell comprising two half shells arranged oppositely, the two half shells are connected by heat melting, at least one of the half shells is provided with a pit, the pit comprises two side surfaces arranged oppositely and a bottom surface connected with the two side surfaces;

[0006] An electric core partially located in the pit, the electric core comprises a plurality of negative electrode plates, a plurality of positive electrode plates and a separator, the separator is folded in a "Z" shape along the length direction to form a plurality of insertion spaces, the negative electrode plates and the positive electrode plates are alternately inserted into the insertion spaces along the first direction;

[0007] Wherein, the bottom surface is perpendicular to the first direction, one layer of the separator close to the bottom surface in the first direction is a first surface, the first surface extends outward to a free section along the length direction of the separator, the free section is bent along the first direction and extends to the side surface, in the first direction, the size of the free section is smaller than the depth of the pit.

[0008] Optionally, in the first direction, the size of the free section is a, the depth of the pit is f, f>a>=1 / 2f.

[0009] Optionally, the two half shells are both provided with the pit, the electric core is located in the two pits, one layer of the separator close to the bottom surface of the two pits in the first direction is the first surface, both the first surfaces extend outward to a free section along the length direction of the separator, both the free sections are bent along the first direction and extend to the side surface of the corresponding pit, in the first direction, the size of the free section is smaller than the depth of the corresponding pit.

[0010] Optionally, in the first direction, the sizes of the two free sections are the same.

[0011] Optionally, in the first direction, the size of the free section is a, and the size of the battery cell is b, 1 / 2b>a≧1 / 3b.

[0012] Optionally, in the first direction, the surface of the first layer and the surface of the last layer of the diaphragm facing away from the insertion space are both adhesive surfaces, and the soft-pack battery further comprises a first adhesive member connected to one of the adhesive surfaces and extending to the other adhesive surface and covering the free section.

[0013] Optionally, a plurality of first adhesive members are provided, and the plurality of first adhesive members are arranged at intervals in a second direction, the distance between two adjacent first adhesive members in the second direction is c, the size of the free section in the first direction is a, 1 / 2a≦c<a, and the second direction is the width direction of the diaphragm.

[0014] Optionally, in the second direction, the distance between the edge of the first first adhesive member and the edge of the adhesive surface is d, and the distance between the edge of the last first adhesive member and the edge of the adhesive surface is also d, the length of the adhesive surface is e, and the ratio of d to e is 1:10-3:10.

[0015] Optionally, the positive electrode sheet extends outward to form a positive electrode tab, and the negative electrode sheet extends outward to form a negative electrode tab, and the soft-pack battery further comprises two lead-out portions, one end of the lead-out portion is located outside the shell, and the other end of the lead-out portion extends into the shell and is connected to the positive electrode tab or the negative electrode tab.

[0016] Optionally, a plurality of second adhesive members are further included, one end of at least one second adhesive member is adhered to the adhesive surface, and the other end covers the area where the positive electrode tab is connected to the positive electrode sheet, one end of at least one second adhesive member is adhered to the adhesive surface, and the other end covers the area where the negative electrode tab is connected to the negative electrode sheet, and the orthographic projection of the second adhesive member in the second direction does not overlap with the orthographic projection of the first adhesive member in the second direction.

[0017] As can be seen from the above, the soft package battery provided in the application comprises a shell and a cell, the shell comprises two half shells arranged oppositely, the two half shells are connected by heat melting, at least one of the half shells is provided with a pit, the pit comprises two opposite sides and a bottom surface connected with the two sides, the cell is located in the pit, the cell comprises a plurality of negative plates, a plurality of positive plates and a separator, the separator is folded in a "Z" shape along the length direction to form a plurality of insertion spaces, the negative plates and the positive plates are alternately inserted into the insertion spaces along the first direction, wherein the bottom surface is perpendicular to the first direction, a layer of the separator close to the bottom surface along the first direction is a first surface, the first surface extends outwardly to a free section along the length direction of the separator, the free section is bent along the first direction and extends to the side, along the first direction, the size of the free section is smaller than the depth of the pit, in this way, the free section is completely located in the pit and is covered by the side of the pit, so that even if the free section is warped or folded in the cell-into-shell process, the free section will not extend out of the pit, and then the free section will not extend into the heat melting sealing area of the shell, which will not affect the heat melting sealing process, and the sealing quality is ensured, and then the safety and performance stability of the battery are improved. In addition, the free section is bent along the first direction and extends to the side, so that the bending of the free section will not increase the thickness of the cell in the first direction, and the manufacturing cost of the whole battery will not be increased. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0019] Figure 1 A first bottom view of the soft package battery of the embodiment of the present application is shown;

[0020] Figure 2 A second bottom view of the soft package battery of the embodiment of the present application is shown;

[0021] Figure 3 A front view of the soft package battery of the embodiment of the present application is shown;

[0022] Figure 4 A third bottom view of the soft package battery of the embodiment of the present application is shown;

[0023] Figure 5 A bottom view of the cell of the embodiment of the present application is shown;

[0024] Figure 6 A front view of the cell of the embodiment of the present application is shown.

[0025] In the figure: 1, cell; 11, diaphragm; 111, first surface; 112, free section; 113, bonding surface; 12, positive plate; 13, negative plate; 14, positive tab; 15, negative tab; 16, insertion space; 2, lead-out part; 3, shell; 31, half shell; 311, punch pit; 3111, side surface; 3112, bottom surface; 32, edge sealing area; 4, first bonding member; 5, second bonding member. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below with reference to specific embodiments and the accompanying drawings.

[0027] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be understood as the general meaning understood by those skilled in the art to which the present application belongs. The terms "first", "second" and similar terms used in the present application do not represent any order, quantity or importance, but are only used to distinguish different components. The terms "include" or "contain" and similar terms mean that the elements or objects before the terms cover the elements or objects listed after the terms and their equivalents, and do not exclude other elements or objects. The terms "connect" or "connected" and similar terms are not limited to physical or mechanical connection, but can include electrical connection, whether direct or indirect. The terms "upper", "lower", "left", "right" and the like are only used to represent relative positional relationships, and when the absolute positions of the described objects change, the relative positional relationships may also change accordingly.

[0028] Generally, the packaging of lithium ion batteries is divided into two categories, one is soft package battery, and the other is metal shell battery. The shell of the metal shell battery includes steel shell and aluminum shell, etc. The soft package battery refers to the battery using an aluminum plastic packaging film as the shell material. The different shell materials determine the different packaging forms of different batteries. The soft package battery adopts heat sealing, and the metal shell battery generally adopts welding (such as laser welding).

[0029] The cell used in the soft package battery is usually a stacked cell. The stacked body can be divided into a laminated stacked body and a Z-shaped stacked body due to different stacking methods. In the laminated stacked body, the positive plate, the diaphragm and the negative plate are all cut into a specific size, and then stacked in sequence to form a laminated stacked body. In the Z-shaped stacked body, the positive plate and the negative plate are cut into a specific size, and the diaphragm is a long strip-shaped structure. The diaphragm is folded in a Z shape, and the positive plate and the negative plate are alternately inserted into the space formed by the Z-shaped folded diaphragm. Since the stacking efficiency of the Z-shaped stacked body is higher, the stacked cell in the existing soft package battery is mostly a Z-shaped stacked cell.

[0030] In the Z-shaped stacked cell, in order to ensure that the diaphragm can cover the entire surface of the cell, a diaphragm larger than the area of the positive and negative plates is usually used, and the diaphragm extends outward in the length direction by a part to ensure that the entire surface of the cell is covered. This part of the diaphragm extending outward is called a free section (the free section is usually the starting section and / or the ending section of the diaphragm).

[0031] However, this approach has some disadvantages. For example, during the cell casing process, the free section may be folded, and the folded free section may enter the aluminum plastic film sealing area, which may cause incomplete sealing or reduced sealing quality, thereby affecting the safety and performance stability of the battery.

[0032] Therefore, how to limit the position of the free section of the diaphragm to ensure that the free section does not enter the sealing area is a problem that needs to be solved.

[0033] Figure 1 A first bottom view of a soft package battery of an embodiment of the application is shown, Figure 2 A second bottom view of a soft package battery of an embodiment of the application is shown. Figure 3 A front view of a soft package battery of an embodiment of the application is shown.

[0034] Referring to Figure 1 , Figure 2 and Figure 3 , the soft package battery comprises:

[0035] A housing 3 comprising two half housings 31 arranged opposite to each other, the two half housings 31 being heat fusion connected, at least one half housing 31 being provided with a pit 311, the pit 311 comprising two side faces 3111 arranged opposite to each other and a bottom face 3112 connected to the two side faces 3111;

[0036] A cell 1 partially located in the pit 311, the cell 1 comprising a plurality of negative plates 13, a plurality of positive plates 12 and a diaphragm 11, the diaphragm 11 being folded in a Z shape along the length direction to form a plurality of insertion spaces 16, the negative plates 13 and the positive plates 12 being sequentially and alternately inserted into the insertion spaces 16 along a first direction;

[0037] The bottom face 3112 is perpendicular to the first direction, in the first direction, a layer of the diaphragm 11 close to the bottom face 3112 is a first surface 111, the first surface 111 extends outwardly along the length direction of the diaphragm 11 by a free section 112, the free section 112 is bent along the first direction and extends to the side face 3111, in the first direction, the size of the free section 112 is smaller than the depth of the pit 311.

[0038] Specifically, the shell 3 is made of an aluminum plastic film material, and the shell 3 includes two half shells 31 arranged oppositely, and the two half shells 31 are hot melt connected, and the hot melt connected part is formed as a sealing edge area 32, and the sealing edge area 32 is located at the periphery of the half shell 31.

[0039] At least one half shell 31 is provided with a punched pit 311, wherein only one half shell 31 can be provided with the punched pit 311, at this time, the shell 3 is a single-side punched pit shell 3, and the battery cell 1 is partially located in the punched pit 311. Alternatively, both of the two half shells 31 are provided with the punched pit 311, at this time, the shell 3 is a double-side punched pit shell 3, and the battery cell 1 is located in the two punched pits 311. In actual implementation, as long as one half shell 31 is provided with the punched pit 311 to accommodate the battery cell 1.

[0040] The sealing edge area 32 formed by hot melting is located at the outer peripheral edge of the punched pit 311. Generally, a certain gap is reserved between the sealing edge area 32 and the punched pit 311 to facilitate the actual punching process and the hot melting process.

[0041] The punched pit 311 includes two opposite side faces 3111 and a bottom face 3112 connected with the two side faces 3111, and the punched pit 311 is arranged on one hand to accommodate the battery cell 1 and on the other hand to limit the battery cell 1, so as to ensure that the battery cell 1 cannot move randomly in the shell 3. Further, the size of the punched pit 311 is matched with the size of the battery cell 1, so as to better accommodate and limit the battery cell 1.

[0042] The battery cell 1 includes a plurality of negative electrode sheets 13, a plurality of positive electrode sheets 12 and a diaphragm 11, the diaphragm 11 is folded in a “Z” shape along the length direction to form a plurality of insertion spaces 16, and the negative electrode sheets 13 and the positive electrode sheets 12 are sequentially and alternately inserted into the insertion spaces 16 along a first direction (i.e. the direction shown in FIG. 1A). Figure 1 Thus, the battery cell 1 is in a “Z-type” sheet stacking mode, and in this mode, the folding stroke of the diaphragm 11 during sheet making of the electrode is shorter, and the cutting and stacking efficiency is higher.

[0043] In the first direction, the layer of the diaphragm 11 close to the bottom face 3112 is a first surface 111, the first surface 111 extends outwardly a free section 112 along the length direction of the diaphragm 11, the free section 112 is bent and extends to the side face 3111 along the first direction, and in the first direction, the size of the free section 112 is smaller than the depth of the punched pit 311, and the depth of the punched pit 311 is the size of the punched pit 311 in the first direction.

[0044] In the first direction, the size (i.e. the size shown in FIG. 1b) of the free section 112 is smaller than the depth (i.e. the size shown in FIG. 1c) of the punched pit 311. Figure 2 Figure 2 ​As shown in FIG. 11, the free section 112 is completely located in the punch pit 311 and covered by the side surface 3111 of the punch pit 311, so that even if the free section 112 is warped or folded in the cell 1 entering the shell process, the free section 112 will not protrude out of the punch pit 311, and further, the free section 112 will not protrude into the hot melt sealing area of the shell 3, and will not affect the hot melt sealing process, ensuring the quality of the sealing, and further improving the safety and performance stability of the battery.

[0045] In addition, the free section 112 is bent in the first direction and extends to the side surface 3111, so that the bending of the free section 112 will not increase the thickness of the cell 1 in the first direction, and will not increase the manufacturing cost of the entire battery.

[0046] In some embodiments, continuing to refer to Figure 2 As shown in FIG. 11, in the first direction, the size of the free section 112 is a, and the depth of the punch pit 311 is f, f>a≧1 / 2f.

[0047] Specifically, when f>a≧1 / 2f, the size of the free section 112 in the first direction is appropriate, which can ensure that the free section 112 is located in the punch pit 311, and ensure that even if the free section 112 is folded, it will not affect the hot melt sealing process, and can also ensure that the free section 112 can cover the end of the pole piece close to the bottom surface 3112 of the punch pit 311, and ensure that even if the free section 112 is folded, it will not cause the pole piece to leak, and avoid internal short circuit.

[0048] When a<1 / 2f, the size of the free section 112 is too small, so that the free section 112 cannot effectively cover the end of the pole piece close to the bottom surface 3112 of the punch pit 311, so that if the free section 112 is folded, it is likely to cause the pole piece to leak, and further cause internal short circuit.

[0049] Figure 4 FIG. 11 shows a third bottom view of the soft package battery of the embodiments of the present application.

[0050] In some embodiments, referring to Figure 4 As shown in FIG. 11, both of the two half shells 31 are provided with a punch pit 311, and the cell 1 is located in the two punch pits 311, and in the first direction, the first surface 111 of the diaphragm 11 close to the bottom surface 3112 of the two punch pits 311 is the first surface 111, and both of the two first surfaces 111 extend outward along the length direction of the diaphragm 11, and both of the two free sections 112 are bent in the first direction and extend to the side surface 3111 of the corresponding punch pit 311, and in the first direction, the size of the free section 112 is less than the depth of the corresponding punch pit 311.

[0051] Specifically, when the two half shells 31 are both provided with the punch pits 311, the shell 3 is a double-sided punch pit structure. For the double-sided punch pit structure, in the first direction, the layer of the diaphragm 11 close to the bottom surface 3112 of the two punch pits 311 is the first surface 111, that is, in the first direction, the first layer and the last layer of the diaphragm 11 close to the bottom surface 3112 are both the first surface 111.

[0052] Both the first surfaces 111 extend outward along the length direction of the diaphragm 11 by a free section 112, so that in the length direction of the diaphragm 11, the diaphragm 11 includes two free sections 112, which can be the starting section and the ending section of the diaphragm 11, respectively.

[0053] Both the free sections 112 are bent along the first direction and extend to the side surface 3111 of the corresponding punch pit 311. In the first direction, the size of the free section 112 is smaller than the depth of the corresponding punch pit 311, so that the two free sections 112 are located in the two punch pits 311, respectively, and each free section 112 is completely covered by the side surface 3111 of the punch pit 311. In this way, even if any one or both of the free sections 112 is warped or folded in the cell 1 shell entering process, the free section 112 will not protrude out of the corresponding punch pit 311, and thus the free section 112 will not protrude into the hot melt sealing area of the shell 3, which will not affect the hot melt sealing process, ensuring the sealing quality, and thus improving the safety and performance stability of the battery.

[0054] Further, both the free sections 112 are bent along the first direction and extend to the side surface 3111 of the corresponding punch pit 311. Preferably, the side surfaces 3111 of the two punch pits 311 to which the two free sections 112 extend are located on the same side of the cell 1, so that the two free sections 112 can cover the same side of the cell 1, improving the safety of the cell 1.

[0055] In some embodiments, in the first direction, the sizes of the two free sections 112 are the same, so that when the punch pit process of the half shell 31 is performed, the depths of the punch pits 311 of the two half shells 31 can be the same. In actual punch pit process, the same mold can be used to punch the two half shells 31, improving the convenience of the punch pit process. At the same time, the same size of the two free sections 112 also facilitates the cell 1 stacking process.

[0056] Further, each free section 112 includes a free end, and an opening is left between the free ends of the two free sections 112, so that the opening is more conducive to the electrolyte entering the inside of the battery cell 1 to better soak the battery cell 1 and is also conducive to the rapid overflow of gas in thermal runaway; at the same time, the opening is arranged so that the two free sections 112 do not contact, avoiding mutual interference of the two free sections 112 to affect the subsequent gluing process; and the two free sections 112 do not contact, which can reduce the amount of the separator 11 under the premise of ensuring that the free section 112 does not warp, thereby reducing the cost.

[0057] Figure 5 A bottom view of the battery cell of the embodiment of the application is shown.

[0058] In some embodiments, referring to Figure 5 as shown, in the first direction, the size of the free section 112 is a, and the size of the battery cell 1 is b, and 1 / 2b>a>1 / 3b.

[0059] Specifically, when the size of the free section 112 and the size of the battery cell 1 satisfy 1 / 2b>a>1 / 3b, the size of the free section 112 is moderate, which can not only reduce the probability of warping of the outermost separator 11, but also avoid mutual interference of the two free sections 112 when the bundling tape is glued, and can reduce the amount of the separator 11 under the premise of ensuring that the free section 112 does not warp, thereby reducing the cost.

[0060] When the size of the free section 112 is less than 1 / 3b, the size of the free section 112 is too small, and the separator 11 is prone to warping; when the size of the free section 112 is greater than 1 / 2b, the size of the free section 112 is too large, and the two free sections 112 will interfere with each other when the bundling tape is glued, which is not conducive to the gluing process, and the amount of the separator 11 is too large, and the cost is high.

[0061] Figure 6 A front view of the battery cell of the embodiment of the application is shown.

[0062] In some embodiments, referring to Figure 5 and Figure 6 in the first direction, the surface of the first layer and the last layer of the separator 11 away from the insertion space 16 is an adhesive surface 113, and the soft-pack battery further includes a first adhesive 4, the first adhesive 4 is connected with one of the adhesive surfaces 113 and extends to the other adhesive surface 113, and the first adhesive 4 covers the two free sections 112.

[0063] Specifically, the bonding surface 113 is actually the same as the first surface 111, except that when only one half shell 31 is provided with the impact pit 311, the diaphragm has only one first surface 111, at this time the first surface 111 is one of the two bonding surfaces 113 close to the bottom surface 3112 of the impact pit; when both half shells 31 are provided with impact pits 311, the diaphragm has two first surfaces 111, at this time the two first surfaces 111 are the two bonding surfaces 113, which are essentially the same.

[0064] The first bonding member 4 is connected with one of the bonding surfaces 113 and extends to the other bonding surface 113, so that the first bonding member 4 can bond the bonding surface 113 and the second surface of the battery cell 1, so as to realize the bundling and restraint of each battery cell 1, ensure that the positive plate 12, the negative plate 13 and the diaphragm 11 cannot be dislocated, and also avoid that the diaphragm 11 of the bonding surface 113 is raised to expose the plate, thereby causing black leakage.

[0065] Meanwhile, the first bonding member 4 covers the two free sections 112, so that the first bonding member 4 can also bundle the two free sections 112 to avoid that the free section 112 is raised to affect the subsequent assembly process.

[0066] In some embodiments, continuing to refer to Figure 6 As shown, the first bonding member 4 is provided with a plurality of first bonding members 4, and the plurality of first bonding members 4 are arranged at intervals in the second direction (i.e. Figure 6 the B direction in the figure), the distance between the adjacent two first bonding members 4 in the second direction is c, the size of the free section 112 in the first direction is a, 1 / 2a≦c

[0067] Specifically, the distance c between the adjacent two first bonding members 4 in the second direction is very critical, if c is too large, the free section 112 between the adjacent two first bonding members 4 which is not restrained is prone to be raised; if c is too small, although it can ensure that the free section 112 will not be raised, but it will also lead to that the amount of the first bonding member 4 is too large, which increases the manufacturing cost.

[0068] Therefore, in the present application, when 1 / 2a≦c

[0069] In some embodiments, continuing to refer to Figure 6 As shown, in the second direction, the distance between the edge of the first first bonding member 4 and the edge of the bonding surface 113 and the distance between the edge of the last first bonding member 4 and the edge of the bonding surface 113 are both d, the length of the bonding surface 113 is e, and the ratio of d to e is 1:10~3:10 。

[0070] Specifically, in the second direction, the first first adhesive 4 and the last first adhesive 4 are the first adhesives 4 arranged close to the edge of the pole piece.

[0071] The distance between the edge of the first first adhesive 4 and the edge of the adhesive surface 113 and the distance between the edge of the last first adhesive 4 and the edge of the adhesive surface 113 are both d, the length of the adhesive surface 113 is e, and the ratio of d to e is 1:10-3:10, which is appropriate for the adhesive position of the first adhesive 4, ensuring that the first adhesive 4 can fix the edge area of the adhesive surface 113 and prevent the edge of the adhesive surface 113 from being folded.

[0072] When the ratio of d to e is less than 1:10, the adhesive position of the first adhesive 4 is too close to the edge of the adhesive surface 113, which requires very fine adhesive process for the first adhesive 4, which is not conducive to actual manufacturing process.

[0073] When the ratio of d to e is greater than 3:10, the adhesive position of the first adhesive 4 is too far from the edge of the adhesive surface 113, so that the first adhesive 4 cannot effectively fix the edge area of the adhesive surface 113, so that the edge of the adhesive surface 113 may still be folded, thereby causing the phenomenon of black leakage or internal short circuit.

[0074] Exemplarily, in the second direction, the ratio of d to e can be 1:10, 1.5:10, 2:10, 2.5:10, 3:10, etc.

[0075] Further, in the second direction, the distance between the edge of the first first adhesive 4 and the adhesive surface 113 and the distance between the edge of the last first adhesive 4 and the adhesive surface 113 can be the same or different.

[0076] In some embodiments, continuing to refer to Figure 3 and Figure 6 As shown, the positive pole piece 12 extends outwardly to form a positive tab 14, the negative pole piece 13 extends outwardly to form a negative tab 15, and the soft package battery further comprises two lead-out portions 2, one end of the lead-out portion 2 is located outside the shell 3, and the other end of the lead-out portion 2 extends into the shell 3 and is connected with the positive tab 14 or the negative tab 15.

[0077] Specifically, the lead-out portion 2 is made of conductive metal material, and the lead-out portion 2 is connected with the positive tab 14 or the negative tab 15, so that the lead-out portion 2 can transmit the signal of the battery inside the cell 1 to the outside to realize the signal transmission of the soft package battery.

[0078] In some embodiments, continuing to refer to Figure 6As shown, the second adhesive member 5 is arranged on the adhesive surface 113 of the diaphragm 11, and covers the area where the positive tab 14 is connected to the positive plate 12, and the area where the negative tab 15 is connected to the negative plate 13. In this way, the second adhesive member 5 can protect the positive tab 14 and the negative tab 15 from being damaged due to pulling or scratching.

[0079] Specifically, in the third direction (i.e. the direction shown in FIG. 13, the third direction is perpendicular to the first direction and the second direction), the size of the second adhesive member 5 is greater than the size of the positive tab 14 and the negative tab 15, so as to ensure that the tabs are completely covered by the second adhesive member 5 in the third direction. Figure 6

[0080] For each battery cell 1, the second adhesive member 5 can be provided with four, two of which correspond to the positive tab 14, and the other two correspond to the negative tab 15. Among the two second adhesive members 5 corresponding to one tab, one is arranged on one adhesive surface 113 of the diaphragm 11, and the other is arranged on the other adhesive surface 113 of the diaphragm 11, so as to bind the tab from both sides.

[0081] In some embodiments, the second adhesive member 5 does not overlap the first adhesive member 4 in the second direction, so as to ensure that the first adhesive member 4 and the second adhesive member 5 do not overlap on the battery cell 1, thereby avoiding the problem that the thickness of the laminated body in the overlapping area is greater than that in other positions, and improving the uniformity of the thickness of the laminated body.

[0082] It should be understood by those skilled in the art that the above discussion of any embodiment is only exemplary and is not intended to limit the scope of the present application (including the claims); under the idea of the present application, the above embodiments or technical features in different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes of different aspects of the present application as described above. In order to be brief, they are not provided in detail.

[0083] Embodiments of the present application are intended to cover all such alternatives, modifications and variations falling within the broad scope of the appended claims. Accordingly, any omission, modification, equivalent replacement, improvement, etc. made in the spirit and principle of the present application shall be included in the protection scope of the present application.​

Claims

1. A pouch battery, characterized by, The shell comprises two half shells arranged oppositely, the two half shells are hot melt connected, at least one of the half shells is provided with a punched pit, the punched pit comprises two side surfaces arranged oppositely and a bottom surface connected with the two side surfaces; The electric core is partially located in the punched pit, the electric core comprises a plurality of negative electrode sheets, a plurality of positive electrode sheets and a diaphragm, the diaphragm is folded in a "Z" shape along the length direction to form a plurality of insertion spaces, the negative electrode sheets and the positive electrode sheets are alternately inserted into the insertion spaces along a first direction; The bottom surface is perpendicular to the first direction, a layer of the diaphragm close to the bottom surface in the first direction is a first surface, the first surface extends outwardly to a free section along the length direction of the diaphragm, the free section is bent along the first direction and extends to the side surface, and the size of the free section in the first direction is smaller than the depth of the punched pit. In the first direction, the size of the free section is a, the depth of the punched pit is f, and f>a>=1 / 2f.

2. The pouch battery of claim 1, wherein, Both of the half shells are provided with the punched pit, the electric core is located in the two punched pits, a layer of the diaphragm close to the bottom surface of the two punched pits in the first direction is the first surface, both of the first surfaces extend outwardly to a free section along the length direction of the diaphragm, both of the free sections are bent along the first direction and extend to the side surface of the corresponding punched pit, and the size of the free section in the first direction is smaller than the depth of the corresponding punched pit. 3.The pouch battery of claim 1, wherein, In the first direction, the sizes of the two free sections are the same.

4. The pouch battery of claim 3, wherein, In the first direction, the size of the free section is a, the size of the electric core is b, and 1 / 2b>a>=1 / 3b. 5.The pouch battery of claim 1, wherein, In the first direction, the surfaces of the first layer and the last layer of the diaphragm away from the insertion space are both adhesive surfaces, and the soft package battery further comprises a first adhesive, the first adhesive is connected with one of the adhesive surfaces and extends to the other adhesive surface, and the first adhesive covers the free section. 6.The pouch battery of claim 1, wherein, The first adhesive is provided with a plurality of first adhesives, the first adhesives are arranged at intervals along a second direction, the distance between two adjacent first adhesives in the second direction is c, the size of the free section in the first direction is a, 1 / 2a<=c<a, and the second direction is the width direction of the diaphragm.

7. The pouch battery of claim 6, wherein, In the second direction, the distance between the edge of the first first adhesive and the edge of the adhesive surface is d, the length of the adhesive surface is e, and the ratio of d to e is 1:10-3:

10.

8. The pouch battery of claim 7, wherein, The positive electrode sheet extends outwardly to a positive electrode tab, the negative electrode sheet extends outwardly to a negative electrode tab, and the soft package battery further comprises two lead-out parts, one end of the lead-out part is located outside the shell, and the other end of the lead-out part extends into the shell and is connected with the positive electrode tab or the negative electrode tab. 9.The pouch battery of claim 7, wherein, ​ 10. The pouch battery of claim 9, wherein, The second adhesive member is arranged to cover the area where the positive tab is connected to the positive electrode sheet, and the second adhesive member is arranged to cover the area where the negative tab is connected to the negative electrode sheet. The second adhesive member is arranged to cover the area where the positive tab is connected to the positive electrode sheet, and the second adhesive member is arranged to cover the area where the negative tab is connected to the negative electrode sheet.

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