Battery monomer and power utilization device

Abstract

The utility model relates to the technical field of batteries, and particularly provides a single battery and an electric device. The electrode assembly is accommodated in the shell and is provided with a tab; the top cover assembly comprises a top cover sheet and a pole column, the top cover sheet is provided with a first through hole, the pole column is installed in the first through hole through a first insulating part, the pole column comprises a main body part and a flange part, the main body part comprises a bottom wall and a side wall, the flange part is connected to the side wall, the pole lug is connected to the bottom wall, and at least one part of the pole lug is contained in the main body part. The second insulating part comprises a first diaphragm, the first diaphragm is pressed between the flange part and the electrode assembly and is provided with a second through hole, and the tab penetrates through the second through hole. According to the utility model, the problem of insufficient space utilization rate in the height direction of the battery monomers is solved, and the space occupied by the top cover assembly is compressed; the insulating film is used for replacing lower plastic, so that the energy density of the battery monomer is further improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a battery cell and an electrical device. Background Technology

[0002] A battery top cover assembly typically includes a top cover sheet and terminals; the top cover sheet connects to the housing and forms an enclosed space with the housing, while the terminals are located on the top cover sheet and are used to connect the battery cell within the enclosed space to external circuitry. To prevent short circuits, existing technologies use a plastic insert to insulate the top cover sheet from the battery cell.

[0003] The top cover plate has raised bumps around the terminals, protruding along the height of the battery cell. These bumps accommodate the tabs or adapter pieces and enhance the structural strength and deformation resistance of the top cover plate. For insulation, the lower plastic also has raised bumps, which are inserted into the raised bumps of the top cover plate. However, the lower plastic bumps present insufficient space for the tabs, and the lower plastic occupies too much space along the height of the battery cell, reducing the space utilization rate within the battery cell. Utility Model Content

[0004] The present invention provides a battery cell and an electrical device that at least solves the problem of insufficient space utilization in the height direction of the battery cell.

[0005] In a first aspect, embodiments of the present invention provide a battery cell comprising:

[0006] The shell has an opening;

[0007] An electrode assembly is housed within the housing, and the electrode assembly is provided with tabs;

[0008] A top cover assembly that snaps into the opening, the top cover assembly including a top cover plate and an electrode post, the top cover plate having a first through hole in its thickness direction, the electrode post being mounted in the first through hole by a first insulating member, the electrode post including a main body and a flange, the main body including a bottom wall and a side wall, the flange being connected to the end of the side wall away from the bottom wall and extending along the width direction of the top cover plate, the electrode tab being connected to the bottom wall, and at least a portion of the electrode tab being accommodated in the main body;

[0009] The second insulating element includes a first diaphragm, which is pressed between the flange and the electrode assembly. The first diaphragm has a second through hole through which the tab passes.

[0010] The battery cell provided in the embodiments of the present invention includes a first insulating member comprising an integrally formed first insulating portion, a second insulating portion, and a third insulating portion. The first insulating portion is located on the side of the top cover sheet facing the electrode assembly, the second insulating portion is located in the first through hole, and the third insulating portion is located on the side of the top cover sheet away from the electrode assembly. The surface of the first insulating portion facing the electrode assembly is flush with the surface of the flange portion facing the electrode assembly.

[0011] The battery cell provided in the embodiment of the present invention has two sets of electrode assemblies, which are arranged sequentially along the width direction of the top cover plate; the electrode tab of each set of electrode assemblies is led out from the inner side of the end face, and the inner side is the side of each set of electrode assemblies that is closer to the other set of electrode assemblies.

[0012] The battery cell provided in the embodiments of the present invention includes a first connecting part, a bending part and a second connecting part connected in sequence in each electrode assembly. The first connecting part is connected to the electrode assembly and the second connecting part is connected to the second sub-part.

[0013] The first connecting portion is located on the side of the first diaphragm facing the electrode assembly, the second connecting portion is located on the side of the first diaphragm away from the electrode assembly, and the bent portion passes through the second through hole.

[0014] In the battery cell provided by the embodiments of the present invention, the bending directions of the bent portions of the two sets of electrode assemblies are arranged facing each other.

[0015] The battery cell provided in the embodiment of the present invention has a bottom wall comprising a first sub-part and a second sub-part. The first sub-part has a through third through hole along its thickness direction, and the second sub-part is mounted in the third through hole and connected to the tab.

[0016] The battery cell provided in the embodiment of the present invention has a groove on the side surface of the first sub-part facing the top cover sheet, the groove wall having a through third through hole, the second sub-part including a pillar part and a plate part, one end of the pillar part being connected to the plate part, the other end extending into the third through hole, the plate part being located in the groove, and the plate part being connected to the tab.

[0017] The battery cell provided in the embodiments of the present invention includes a second insulating member further comprising a second diaphragm and a third diaphragm. There are two second diaphragms, which are respectively connected to the two sides of the first diaphragm in the width direction of the top cover sheet, and are respectively used to cover the two sides of the electrode assembly in the thickness direction. The third diaphragm is connected to one of the second diaphragms and is used to cover the bottom surface of the electrode assembly.

[0018] The battery cell provided in the embodiments of the present invention includes a first sub-film and a second sub-film, both of which are provided with notches, and the notches on the first sub-film and the second sub-film are spliced ​​together to form a second through hole;

[0019] The second insulating element further includes a second diaphragm and a third diaphragm. The third diaphragm covers the bottom surface of the electrode assembly. There are two second diaphragms, which are respectively connected to the two sides of the third diaphragm in the thickness direction of the electrode assembly and are used to cover the two sides of the electrode assembly along its thickness direction. The first sub-diaphragm is connected to one of the second diaphragms, and the second sub-diaphragm is connected to the other of the second diaphragms.

[0020] Secondly, embodiments of the present invention also provide an electrical device comprising the battery cell described in any of the above embodiments.

[0021] The battery cell and power device provided by the present invention solve the problem of insufficient space utilization in the height direction of the battery cell. By setting the electrode post structure, the space occupied by the top cover assembly is reduced in the height direction. The insulating film replaces the lower plastic in the related technology. In combination with the electrode post structure, it further improves the internal space utilization of the battery cell while providing insulation, which is conducive to improving the energy density of the battery cell. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0023] Figure 1 This is a schematic diagram of the structure of a battery cell in an embodiment of the present invention.

[0024] Figure 2 yes Figure 1 The cell shown is a cross-sectional view along the A-A' direction.

[0025] Figure 3 yes Figure 2 The cross-sectional view shown is an isometric enlarged view at the tab.

[0026] Figure 4 This is a schematic diagram of the electrode assembly in an embodiment of the present invention.

[0027] Figure 5 yes Figure 4 Enlarged diagram of point B in the middle.

[0028] Figure 6 This is an exploded view of a battery cell in an embodiment of the present invention.

[0029] Figure 7 yes Figure 6 The diagram shows the structure of the electrode assembly and the first membrane in the battery cell.

[0030] Figure 8 yes Figure 7 A schematic diagram of the structure of the first diaphragm before folding.

[0031] Figure 9 yes Figure 7 A schematic diagram of the structure of the first diaphragm after folding.

[0032] Figure 10 This is an exploded view of another battery cell in an embodiment of the present invention.

[0033] Figure 11 yes Figure 10 A schematic diagram of the structure of the first diaphragm before folding.

[0034] Figure 12 yes Figure 10 A schematic diagram of the structure of the first diaphragm after folding.

[0035] Figure 13 This is a schematic diagram of the top cover assembly in an embodiment of the present invention.

[0036] Figure 14 yes Figure 13 A structural schematic diagram of the top cover assembly from another angle.

[0037] Figure 15 yes Figure 13 The top cover assembly shown is an isometric sectional view along the C-C' direction.

[0038] Figure 16 yes Figure 15 Enlarged diagram of point D in the middle.

[0039] Figure 17 This is a schematic diagram of the structure of the second sub-part of the pole post in an embodiment of the present invention.

[0040] Figure 18 This is a schematic diagram of the structure of the first sub-part, sidewall, and flange of the pole post in an embodiment of the present invention.

[0041] Figure 19 yes Figure 18 The isometric half-section view of the structure shown.

[0042] Figure 20 This is a schematic diagram of the structure of the first insulating element in an embodiment of the present invention.

[0043] Figure 21 yes Figure 20The isometric half-sectional view of the first insulating component is shown.

[0044] Figure 22 This is a schematic diagram of the top cover sheet in an embodiment of the present invention.

[0045] Figure 23 yes Figure 22 The top cover plate shown is an isometric sectional view along the E-E' direction.

[0046] Figure 24 yes Figure 23 Enlarged schematic diagram at point F in the middle.

[0047] The above figures include the following reference numerals:

[0048] 1. Housing; 11. Opening; 2. Electrode assembly; 21. Tab; 2101. First connecting part; 2102. Bending part; 2103. Second connecting part; 22. Cell body; 3. Top cover assembly; 4. Top cover plate; 41. First through hole; 5. Terminal post; 51. Main body; 5101. Bottom wall; 5102. Side wall; 52. Flange; 6. First insulating component; 61. First insulating part; 62. Second insulating part; 63. Third insulating part; 7. Second insulating component; 71. First diaphragm; 7101. Second through hole; 7102. First sub-diaphragm; 7103. Second sub-diaphragm; 7104. Notch; 72. Second diaphragm; 73. Third diaphragm; 81. First sub-part; 8101. Groove; 82. Second sub-part; 8201. Post; 8202. Plate; 83. Third through hole. Detailed Implementation

[0049] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0051] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0052] Embodiment 1 of this utility model provides a battery cell that uses an electrode post structure to compress the space occupied by the top cover assembly in the height direction; and uses an insulating film to replace the lower plastic in related technologies, which, in conjunction with the electrode post structure, not only provides insulation but also further improves the internal space utilization of the battery cell, thus helping to increase the energy density of the battery cell.

[0053] Specifically, refer to Figure 1 , Figure 6 and Figure 10 As shown, the battery cell includes a housing 1, an electrode assembly 2, and a top cover assembly 3. The housing 1 has an opening 11, and the electrode assembly 2 is housed in the housing 1 and has tabs 21. The top cover assembly 3 fastens to the opening 11 of the housing 1 to close the housing 1, providing a closed housing space for the electrode assembly 2 inside the housing 1.

[0054] Furthermore, referring to Figures 13 to 16 As shown, the top cover assembly 3 includes a top cover plate 4 and an electrode post 5. The top cover plate 4 fastens to the opening 11 of the housing 1. In this embodiment of the present invention, the opening 11 is provided on one side of the housing 1 in the height direction. Therefore, when the top cover plate 4 fastens to the opening 11 of the housing 1, the thickness direction of the top cover plate is the same as the height direction of the housing 1, and the thickness direction of the top cover plate 4 is the same as the height direction of the battery cell obtained after fastening. The top cover plate 4 is also provided with a first through hole 41 extending along its thickness direction.

[0055] The electrode post 5 is installed and fixed in the first through hole 41. The electrode post 5 includes a main body 51 and a flange 52. The main body 51 includes a bottom wall 5101 and a side wall 5102. The bottom wall 5101 is located on the side of the side wall 5102 facing away from the housing 1 in the extending direction. The bottom wall 5101 and the side wall 5102 enclose an open space facing the housing 1. The electrode tab 21 of the electrode assembly 2 inside the housing 1 is at least partially accommodated in the main body 51, specifically within the open space enclosed by the bottom wall 5101 and the side wall 5102. The electrode tab 21 is connected to the bottom wall 5101, specifically to the surface of the bottom wall 5101 facing the housing 1 in the thickness direction of the top cover plate 4.

[0056] Preferably, in this embodiment, the thickness direction of the bottom wall 5101 of the main body 51 is consistent with the thickness direction of the top cover plate 4. At this time, the bottom wall 5101 of the main body 51 and the top cover plate 4 are arranged parallel to each other, which can save space in the thickness direction and improve the space utilization rate in the height direction of the battery cell.

[0057] The flange 52 of the pole post 5 is connected to the end of the side wall 5102 away from the bottom wall 5101 and extends along the width direction of the top cover plate 4. The width direction of the top cover plate 4 is perpendicular to the thickness direction of the top cover plate 4. One end of the flange 52 is connected to the side wall 5102, and the other end is bent away from the open space that accommodates the pole lug 21. After being bent, the other end protrudes from the main body 51 to form a flange.

[0058] Furthermore, referring to Figure 13 As shown, the bottom wall 5101 of the main body 51 includes a first sub-part 81 and a second sub-part 82. The first sub-part 81 is connected to the side wall 5102 of the main body 51, and a through third hole 83 is provided on the first sub-part 81 along the thickness direction. The second sub-part 82 is installed in the third through hole 83 and is used to connect the tab 21. A groove 8101 is provided on the side surface of the first sub-part 81 facing the top cover plate 4. Since the main body 51 also has a side wall 5102 connecting the bottom wall 5101, the bottom wall 5101 is located on the side of the top cover plate 4 away from the electrode assembly 2 in the height direction of the battery cell. Therefore, the side surface of the first sub-part 81 facing the top cover plate 4 is the side surface of the bottom wall 5101 facing the open space accommodating the tab 21.

[0059] The groove 8101 is recessed from the surface of the first sub-part 81 facing the top cover plate 4 to the surface away from the top cover plate 4 and the electrode assembly 2. The groove 8101 is disposed around the outer periphery of the third through hole 83, and the groove 8101 is in communication with the third through hole 83. The groove wall of the groove 8101 has a through third through hole 83, which is located on the bottom wall of the groove 8101.

[0060] The second sub-part 82 connects to the first sub-part 81 and includes a column part 8201 and a plate part 8202. The column part 8201 extends along the thickness direction of the top cover plate 4, and one end of the column part 8201 in the extending direction connects to the plate part 8202, which is used to connect the electrode lug 21. The cross-sectional area of ​​the column part 8201 is smaller than the cross-sectional area of ​​the plate part 8202. Here, the cross-section refers to the section of the column part 8201 and the plate part 8202 perpendicular to the thickness direction of the top cover plate 4. That is, the plate part 8202 protrudes from the vertical surface of the column part 8201. Preferably, the column part 8201 and the plate part 8202 are coaxially connected, which improves assembly stability.

[0061] One end of the column portion 8201, extending away from the plate portion 8202 in the extending direction, extends into the third through hole 83. This end of the column portion 8201, extending into the third through hole 83, is used to connect to the first sub-part 81, thereby fixing the second sub-part 82 and the first sub-part 81. Therefore, the end face of the end of the column portion 8201 extending into the third through hole 83 can be flush with the opening of the third through hole 83, or located inside the third through hole 83, or protruding from the third through hole 83. The specific position of the end of the column portion 8201 away from the plate portion 8202 is not limited here; it is determined by the actual requirement that the end of the column portion 8201 away from the plate portion 8202 can meet the connection requirements with the first sub-part 81.

[0062] In the first embodiment of this utility model, the vertical surface of the column portion 8201 is closely attached to the wall of the third through hole 83. Preferably, the end face of the column portion 8201 is flush with the opening of the third through hole 83, i.e., the surface of the first sub-part 81 furthest from the top cover plate 4. This avoids thickening of the top cover assembly 3 when it extends beyond the third through hole 83, which would affect the battery energy density. It also avoids situations where the column portion 8201 is located inside the third through hole 83, making the connection with the first sub-part 81 difficult or insufficient in strength.

[0063] The area of ​​the plate portion 8202 protruding from the post portion 8201 is accommodated in the groove 8101 of the first sub-portion 81. The surface of the plate portion 8202 away from the post portion 8201 is used to connect the electrode tab 21, so that the electrode tab 21 is electrically connected to the pole post 5. Preferably, the surface of the plate portion 8202 away from the post portion 8201 is flush with the surface of the first sub-portion 81 where the groove 8101 is provided. This avoids the height difference caused by the two not being flush, which would create a step that would interfere with or scratch the surface of the electrode tab 21, and also avoids the plate portion 8202 extending beyond the first sub-portion 81 and occupying too much space. The flush arrangement can provide as much accommodating space as possible for the electrode tab 21 within the main body portion 51, making it easy to place the electrode tab 21 and preventing the electrode tab 21 from being inserted upside down.

[0064] Specifically, refer to Figure 16 , Figure 20 and Figure 21As shown, the battery cell also includes a first insulating member 6. The terminal 5 of the top cover assembly 3 is fixed to the first through hole 41 of the top cover plate 4 through the first insulating member 6. The first insulating member 6 is used to insulate the terminal 5 from the top cover plate 4, prevent the terminal 5 from conducting with the top cover plate 4 or other components, and ensure the insulation performance between the positive and negative terminals. It also prevents metal parts from directly contacting the electrode assembly 2, avoids the risk of short circuit, and prevents electrolyte leakage from corroding the top cover plate 4.

[0065] Furthermore, the first insulating member 6 is configured as an integrally molded structure, comprising an integrally molded first insulating portion 61, a second insulating portion 62, and a third insulating portion 63. The first insulating portion 61, the second insulating portion 62, and the third insulating portion 63 are connected sequentially. The first insulating portion 61 is located on the side of the top cover plate 4 facing the housing 1 and the electrode assembly 2 in the thickness direction; the second insulating portion 62 is located in the first through hole 41 and abuts against the hole wall of the first through hole 41; and the third insulating portion 63 is located on the side of the top cover plate 4 away from the housing 1 and the electrode assembly 2. In some embodiments, the first insulating member 6 can be injection molded.

[0066] It should be noted that the surface of the first insulating portion 61 facing the electrode assembly 2 is flush with the surface of the flange portion 52 facing the electrode assembly 2. This avoids the height difference that could cause step-like structural interference or scratches on the tab 21 if the surfaces of the first insulating portion 61 and the flange portion 52 are not flush. The flush arrangement also prevents the first insulating portion 61 or the flange portion 52 from occupying too much space in the height direction of the battery cell. At the same time, the flush arrangement can also improve the stability of the battery cell structure and prevent deformation caused by uneven stress in various parts of the top cover plate 4.

[0067] In the first embodiment of this utility model, the battery cell is provided with two sets of electrode assemblies 2, and the tabs 21 are led out from the cell body 22 in the electrode assembly 2. The cell bodies 22 of the two sets of electrode assemblies 2 respectively lead out the tabs 21. The two sets of electrode assemblies 2 are arranged along the width direction of the top cover plate 4, corresponding to the extension position of the flange portion 52 of the pole post 5.

[0068] When the two sets of electrode assemblies 2 are arranged along the width direction of the top cover plate 4, the two battery cell bodies 22 are also arranged along the width direction of the top cover plate 4. Both sets of battery cell bodies 22 have tabs 21 extending from their end faces near the top cover assembly 3 along the thickness direction of the top cover plate 4. Each battery cell body 22 has one set of positive tabs and one set of negative tabs extending from its end face, and these positive and negative tabs are arranged along the length direction of the top cover plate 4. The length direction of the top cover plate 4 is perpendicular to both its width and thickness directions.

[0069] Both sets of electrode assemblies 2 have identical polarity tabs 21 electrically connected to the surface of the plate portion 8202 away from the post portion 8201. The positive tabs led out from the two battery cell bodies 22 are opposite each other along the width direction of the top cover plate 4, and the negative tabs led out from the two battery cell bodies 22 are opposite each other along the width direction of the top cover plate 4. At least a portion of the positive tabs of the two opposing battery cell bodies 22 are housed within the main body portion 51 of the positive electrode post, and at least a portion of the negative tabs of the two opposing battery cell bodies 22 are housed within the main body portion 51 of the negative electrode post.

[0070] Each electrode assembly 2 has its tabs 21 extending from the inner side of the end face of the cell body 22. The inner side is one side of the cell body 22 closest to another cell body 22 in the width direction of the top cover plate 4. Extending from the inner side in the width direction of the top cover plate 4 facilitates the convergence of the tabs 21 within the body portion 51, making tab shaping and welding to the terminal post 5 easier. Shortening the length of the tabs 21 between the extension position and the welding position to the plate portion 8202 reduces the risk of tab bending damage, decreases current transmission line losses, and improves the battery's charging and discharging efficiency. It also makes the arrangement of the tabs 21 more compact and regular, reducing the risk of mutual interference between the tabs 21 and enhancing the stability and safety of the battery structure.

[0071] Furthermore, referring to Figure 4 and Figure 5 As shown, each electrode assembly 2's tab 21 includes a first connecting portion 2101, a bending portion 2102, and a second connecting portion 2103 connected in sequence. The first connecting portion 2101 connects to the inner side of the end face of the cell body 22 in the electrode assembly 2. The two ends of the bending portion 2102 are respectively connected to the first connecting portion 2101 and the second connecting portion 2103 to bend the tab 21 from the lead-out direction to connect with the plate portion 8202 of the electrode post 5. The bending directions of the bending portions 2102 of the two sets of electrode assemblies 2 are arranged facing each other to guide the second connecting portion 2103 to the second sub-part 82 of the electrode post 5. The second connecting portion 2103 connects to the surface of the plate portion 8202 of the second sub-part 82.

[0072] The second connection portion 2103 of the tabs 21 leading out from the two sets of electrode assemblies 2 are connected to the side surface of the plate portion 8202 of the second sub-part 82 of the electrode post 5 away from the post portion 8201. The area where the second connection portion 2103 of the two sets of tabs 21 are connected to the plate portion 8202 is also arranged along the width direction of the top cover plate 4 and is symmetrically arranged on the plate portion 8202 to ensure that the connection area is the same when the tabs 21 of the two sets of cell assemblies are electrically connected to the electrode post 5, and the impedance of the current conduction path of the cell body 22 of the two sets of electrode assemblies 2 is consistent during charging and discharging. This avoids the cell body 22 bearing excessive current due to the difference in connection area, reduces uneven heating and local loss, and improves the charging and discharging efficiency and stability of the battery cell. In addition, the symmetry between the plate 8202 and the two sets of electrode tabs can make the welding or pressing stress distribution between the electrode tab 21 and the electrode post 5 more uniform, avoid pulling the electrode tab 21 and causing it to break, and also avoid the electrode tab 21 of a certain set of electrode assembly 2 being too long or too short, causing the electrode tab 21 to be inserted into the electrode, thus making the reliability stronger.

[0073] Specifically, refer to Figures 7 to 9 , Figure 11 and Figure 12 As shown, the battery cell also includes a second insulating member 7. In this embodiment, the second insulating member 7 is used to insulate the top cover sheet 4 of the electrode assembly 2 and the top cover assembly 3.

[0074] The second insulating member 7 includes a first diaphragm 71 having a second through hole 7101. The first connecting portion 2101 of the tab 21 is located on the side of the first diaphragm 71 facing the electrode assembly 2. The bent portion 2102 of the tab 21 passes through the second through hole 7101 of the first diaphragm 71, causing the second connecting portion 2103 of the tab 21 to protrude, located on the side of the first diaphragm 7 away from the electrode assembly 2 and exposed to the outside of the second insulating member 7 for connection with the pole post 5.

[0075] The first diaphragm 71 covers at least a portion of the surface of the cell body 22 of the electrode assembly 2, exposing the area of ​​the tab 21 of the electrode assembly 2 used for electrical connection. The second insulating member 7 can prevent the cell body 22 from short-circuiting with the housing 1. To this end, the second through hole 7101 on the first diaphragm 71 corresponds to the size of the tab 21. If the second through hole 7101 is too small, it is inconvenient for the tab 21 to pass through and it will press against the tab 21, causing the first diaphragm 71 to fail to fit against the end face of the cell body 22. If the second through hole 7101 is too large, it will expose other areas of the electrode assembly 2 except for the tab 21, posing a risk of short circuit.

[0076] Continuing, since the size of the second through hole 7101 is adapted to the tab 21, a portion of the tab 21 is located within the main body 51 of the pole post 5, and the flange 52 of the pole post 5 is folded outwards. (Refer to...) Figure 2 , Figure 3 and Figure 7As shown, the first diaphragm 71 is pressed around the opening of the second through hole 7101 by the flange portion 52 of the electrode post 5, and is pressed between the flange portion 52 and the electrode assembly 2. The flange portion 52 is used to press and hold the surface of the first diaphragm 71, which can limit and fix the first diaphragm 71. In this embodiment, the first diaphragm 71 of the second insulating member 7 can be fixed by the electrode post structure without heat melting, which greatly improves the processing and assembly efficiency of the battery cell.

[0077] Since the main body 51 of the electrode post 5 provides a space for the second connecting portion 2103 of the electrode tab 21, there is no need to provide a protruding lower plastic to accommodate the electrode tab 21. In this embodiment, the second insulating member 7 replaces the lower plastic of the top cover in the related art. The second insulating member 7 is set as an insulating film. In some embodiments, the second insulating member 7 is preferably set as Mylar film. The main component of Mylar film is polyethylene terephthalate (PET). Mylar film has excellent insulation performance and is resistant to electrolyte corrosion. It also has good high temperature resistance and mechanical strength, good flexibility, and can be tightly attached to the main body 22 of the battery cell. It is thin, light, easy to process, and suitable for automated production. In other embodiments, the second insulating member 7 can also be a thin film made of insulating materials such as polyimide (PI) film.

[0078] The Mylar membrane, with a thickness in the micrometer range, is significantly thinner than the millimeter-thickness of the lower plastic insulation components in related technologies. This greatly reduces the space occupied by the internal insulation material of the battery cell, increasing the cell arrangement density and thus improving the battery's energy density. The Mylar membrane exhibits good electrical insulation and chemical stability, providing reliable insulation protection and reducing the risk of insulation failure caused by aging and moisture absorption of the lower plastic insulation material. Furthermore, the Mylar membrane can be automatically wound and wrapped around the battery cell body 22, ensuring a tight fit between the membrane and the cell body 22 surface. This is more convenient, cost-effective, and lighter than the lower plastic cutting process, contributing to the achievement of lightweight battery cells.

[0079] Furthermore, in some implementations, reference is made to... Figures 7 to 9 As shown, the first diaphragm 71 covers the top. The top is the side of the electrode assembly 2 closest to the top cover assembly 3 in the height direction of the battery cell, that is, the side from which the electrode tab 21 of the electrode assembly 2 is led out.

[0080] In this embodiment, the first diaphragm is positioned on the tab 21 through the second through hole 7101. After the area of ​​the first diaphragm 71 outside the second through hole 7101 is attached to the end face of the lead-out tab 21 of the electrode assembly 2, the other areas of the first diaphragm 71 are sequentially covered to cover the other surfaces of the electrode assembly 2. At the same time, the second insulating member 7 also includes a second diaphragm 72 and a third diaphragm 73. There are two second diaphragms 72, which are respectively connected to the two sides of the first diaphragm 71 in the width direction of the top cover plate 4, and are used to cover the two sides of the cell body 22 of the electrode assembly 2. The third diaphragm 73 is connected to one of the second diaphragms 72 and is used to cover the bottom surface of the electrode assembly 2.

[0081] Furthermore, in some other embodiments, reference is made to... Figures 10 to 12 As shown, the first diaphragm 71 covers the bottom. The bottom is the side of the electrode assembly 2 away from the top cover assembly 3 in the height direction of the battery cell, that is, the side opposite the end face of the electrode assembly 2 with the tab 21 leading out, and the side of the electrode assembly 2 away from the opening 11 of the housing 1.

[0082] In this embodiment, the first diaphragm 71 includes a first sub-diaphragm 7102 and a second sub-diaphragm 7103. Both the first sub-diaphragm 7102 and the second sub-diaphragm 7103 have notches 7104. The notches 7104 on the first sub-diaphragm 7102 and the second sub-diaphragm 7103 are joined to form a second through-hole 7101. After the first diaphragm 71 tightly covers and adheres to the electrode assembly 2 from the bottom, other areas are sequentially covered until the notches 7104 of the first sub-diaphragm 7102 and the second sub-diaphragm 7103 are joined to form the second through-hole 7101. Meanwhile, the second insulating member 7 also includes a second diaphragm 72 and a third diaphragm 73. The third diaphragm 73 covers the bottom surface of the electrode assembly 2. There are two second diaphragms 72, which are respectively connected to the two sides of the third diaphragm 73 in the thickness direction of the electrode assembly 2, and are respectively used to cover the two sides of the electrode assembly 2 along its thickness direction. The first sub-diaphragm 7102 is connected to one of the second diaphragms 72, and the second sub-diaphragm 7103 is connected to the other second diaphragm 72.

[0083] In the above embodiments, the second insulating member 7 covers and insulates the surface area of ​​the electrode assembly 2 except for the tab 21. The second insulating member 7 is divided into a first diaphragm 71, a second diaphragm 72 and a third diaphragm 73, or a first sub-diaphragm 7102, a second sub-diaphragm 7103, a second diaphragm 72 and a third diaphragm 73, in order to facilitate the application of insulating films to different surfaces to adapt to the shape of the electrode assembly 2.

[0084] The battery cell provided in Embodiment 1 of this utility model achieves the goal of lightweighting and is simple to process and assemble. It also improves the utilization rate of internal space and energy density.

[0085] On the other hand, Embodiment 2 of this utility model also provides an electrical device, which includes the battery cell provided in Embodiment 1 above. Therefore, this electrical device includes all the technical effects of the battery cell described above. Since the technical effects of the battery cell have been described in detail above, they will not be repeated here.

[0086] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0087] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0088] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: The shell (1) has an opening (11); Electrode assembly (2) is housed in the housing (1), and the electrode assembly (2) is provided with tabs (21). Top cover assembly (3) fastens the opening (11). The top cover assembly (3) includes a top cover plate (4) and an electrode post (5). The top cover plate (4) has a through first through hole (41) in its thickness direction. The electrode post (5) is installed in the first through hole (41) through a first insulating member (6). The electrode post (5) includes a main body (51) and a flange (52). The main body (51) includes a bottom wall (5101) and a side wall (5102). The flange (52) is connected to the side wall (5102) at one end away from the bottom wall (5101) and extends along the width direction of the top cover plate (4). The electrode lug (21) is connected to the bottom wall (5101). At least a portion of the electrode lug (21) is accommodated in the main body (51). The second insulating member (7) includes a first diaphragm (71) pressed between the flange (52) and the electrode assembly (2), the first diaphragm (71) having a second through hole (7101), through which the tab (21) passes.

2. The battery cell according to claim 1, characterized in that, The first insulating member (6) includes an integrally formed first insulating part (61), a second insulating part (62) and a third insulating part (63). The first insulating part (61) is located on the side of the top cover plate (4) facing the electrode assembly (2). The second insulating part (62) is located in the first through hole (41). The third insulating part (63) is located on the side of the top cover plate (4) away from the electrode assembly (2). The surface of the first insulating part (61) facing the electrode assembly (2) is flush with the surface of the flange part (52) facing the electrode assembly (2).

3. The battery cell according to claim 2, characterized in that, The number of electrode assemblies (2) is two sets, and the two sets of electrode assemblies (2) are arranged sequentially along the width direction of the top cover plate (4); each set of electrode assemblies (2) leads out the tab (21) from the inside of the end face, and the inside is the side of each set of electrode assemblies (2) that is close to the other set of electrode assemblies (2).

4. The battery cell according to claim 3, characterized in that, Each electrode assembly (2) includes a first connecting part (2101), a bending part (2102), and a second connecting part (2103) connected in sequence. The first connecting part (2101) is connected to the electrode assembly (2), and the second connecting part (2103) is connected to the second sub-part (82). The first connecting portion (2101) is located on the side of the first diaphragm (71) facing the electrode assembly (2), the second connecting portion (2103) is located on the side of the first diaphragm (71) away from the electrode assembly (2), and the bending portion (2102) passes through the second through hole (7101).

5. The battery cell according to claim 4, characterized in that, The bending directions of the bent portions (2102) of the two sets of electrode assemblies (2) are arranged facing each other.

6. The battery cell according to claim 2, characterized in that, The bottom wall (5101) includes a first sub-part (81) and a second sub-part (82). The first sub-part (81) has a through third through hole (83) along its thickness direction. The second sub-part (82) is installed in the third through hole (83) and is connected to the tab (21).

7. The battery cell according to claim 6, characterized in that, The first sub-part (81) has a groove (8101) on one side surface facing the top cover plate (4). The groove wall of the groove (8101) has a through third through hole (83). The second sub-part (82) includes a column part (8201) and a plate part (8202). One end of the column part (8201) is connected to the plate part (8202), and the other end extends into the third through hole (83). The plate part (8202) is located in the groove (8101) and is connected to the tab (21).

8. The battery cell according to any one of claims 1 to 7, characterized in that, The second insulating member (7) further includes a second diaphragm (72) and a third diaphragm (73). There are two second diaphragms (72), which are respectively connected to the first diaphragm (71) on both sides of the top cover sheet (4) in the width direction and are respectively used to cover the two sides of the electrode assembly (2) in the thickness direction. The third diaphragm (73) is connected to one of the second diaphragms (72) and is used to cover the bottom surface of the electrode assembly (2).

9. The battery cell according to any one of claims 1 to 7, characterized in that, The first diaphragm (71) includes a first sub-diaphragm (7102) and a second sub-diaphragm (7103). Both the first sub-diaphragm (7102) and the second sub-diaphragm (7103) are provided with notches (7104). The notches (7104) on the first sub-diaphragm (7102) and the second sub-diaphragm (7103) are spliced ​​together to form the second through hole (7101). The second insulating member (7) further includes a second diaphragm (72) and a third diaphragm (73). The third diaphragm (73) covers the bottom surface of the electrode assembly (2). There are two second diaphragms (72), which are respectively connected to the third diaphragm (73) on both sides of the electrode assembly (2) in the thickness direction, and are respectively used to cover the two sides of the electrode assembly (2) along its thickness direction. The first sub-diaphragm (7102) is connected to one of the second diaphragms (72), and the second sub-diaphragm (7103) is connected to the other second diaphragm (72).

10. An electrical device, characterized in that, Includes the battery cell as described in any one of claims 1 to 9.

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