Battery

Abstract

The utility model provides a battery. The battery comprises a naked battery cell; the insulating film coats the outer side of the bare battery cell, and a first through hole is formed in the insulating film; the bottom supporting plate is arranged on one side, far away from the naked battery cell, of the insulating film, a second through hole is formed in the bottom supporting plate, and the second through hole is communicated with the first through hole; the insulating layer is arranged between the naked battery core and the insulating film; and along the axial direction of the first through hole, the orthographic projection of the first through hole on the naked battery cell is at least partially overlapped with the orthographic projection of the insulating layer on the naked battery cell. According to the battery provided by the invention, at least part of the first through hole in the insulating film can be shielded through the insulating layer, so that the opening area, close to the naked battery cell, of the first through hole is reduced, and the risk that foreign matters generated by the naked battery cell enter the first through hole, penetrate through the first through hole and the second through hole and then are in contact with the shell is reduced; and the electrical property and the safety of the battery can be improved.

Description

TECHNICAL FIELD

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

[0002] The battery comprises a shell, a top cover and a bare cell, and the bare cell is arranged in a space formed by the shell and the top cover. The outer side of the bare cell is covered with an insulating film, and a bottom supporting plate is further arranged between the insulating film and the shell and adheres to the insulating film. Generally, the bottom supporting plate is located on the side of the bare cell away from the top cover.

[0003] During assembly of the battery, in order to meet the requirements of automatic line assembly, a positioning hole (hereinafter referred to as a positioning hole) needs to be arranged on the insulating film and the bottom supporting plate. However, foreign matters (for example, active substances falling from the pole piece of the bare cell) generated during assembly and use of the bare cell may also enter the positioning hole and contact the shell through the positioning hole, thereby adversely affecting the performance of the battery. CONTENT OF THE UTILITY MODEL

[0004] Therefore, the purpose of the present application is to provide a battery to at least partially solve the problem that foreign matters generated by the bare cell contact the shell through the positioning hole on the insulating film and the bottom supporting plate, thereby adversely affecting the performance of the battery.

[0005] To achieve the above purpose, the present application provides a battery, comprising: a bare cell; an insulating film, covering the outer side of the bare cell, the insulating film being provided with a first through hole; a bottom supporting plate, arranged on the side of the insulating film away from the bare cell, the bottom supporting plate being provided with a second through hole, the second through hole being in communication with the first through hole; an insulating layer, arranged between the bare cell and the insulating film; along the axial direction of the first through hole, the orthographic projection of the first through hole on the bare cell is a through hole projection, the orthographic projection of the insulating layer on the bare cell is a layer projection, and the through hole projection and the layer projection at least partially overlap.

[0006] Optionally, the thickness of the insulating layer is h, 30 μm≤h≤50 μm; and the total thickness of the insulating film and the bottom supporting plate is H, 0.4 mm≤H≤0.7 mm.

[0007] Optionally, the through hole projection is located within the layer projection.

[0008] Optionally, the minimum distance between the edge of the through hole projection and the edge of the layer projection is d, d≥5 mm.

[0009] Optionally, the insulating layer comprises an insulating base connected to the bare battery cell through an adhesive layer; the bare battery cell comprises a bottom surface close to the bottom plate, and two side surfaces oppositely arranged along a first direction, and the two side surfaces are respectively connected to the bottom surface; the insulating layer extends along the first direction, and the insulating layer comprises a first region and a second region located at least one side of the first region along the first direction; the first region corresponds to the bottom surface, and the second region is connected to the side surface; along the axial direction of the first through hole, the orthographic projection of the first region on the bottom surface forms the layer projection; and the orthographic projection of the first through hole on the bottom surface forms the through hole projection.

[0010] Optionally, the size of the second region along the extension direction of the insulating layer is L, and L≥20mm.

[0011] Optionally, the bare battery cell comprises a plurality of positive electrode sheets and a plurality of negative electrode sheets alternately arranged along the first direction, and a diaphragm separating the positive electrode sheets and the negative electrode sheets; the diaphragm forms a diaphragm opening on the bottom surface, and the diaphragm opening exposes the positive electrode sheet and / or the negative electrode sheet.

[0012] Optionally, the end of the diaphragm extends to one side of the bare battery cell close to the bottom plate, and the surface of the end close to the bottom plate forms the bottom surface.

[0013] Optionally, the bare battery cell has a laminated structure, and the diaphragm is folded in a "Z" shape to form a plurality of insertion spaces, and the plurality of insertion spaces comprise first spaces and second spaces alternately arranged along the first direction, the positive electrode sheets are inserted into the first spaces, the negative electrode sheets are inserted into the second spaces, and the openings of the first spaces and / or the second spaces on the bottom surface form the diaphragm openings.

[0014] Optionally, the bare battery cell has a winding structure, the diaphragm comprises a first surface and a second surface oppositely arranged, a plurality of the positive electrode sheets are connected to the first surface, and a plurality of the negative electrode sheets are connected to the second surface; the diaphragm is wound to form the winding structure; the end of the winding structure along the winding axis forms the bottom surface, and the opening between the adjacent two turns of the diaphragm on the bottom surface forms the diaphragm opening.

[0015] As can be seen from the above, the battery provided by the application can at least partially shield the first through hole on the insulating film through the insulating layer, so as to reduce the opening area of the first through hole close to the bare battery cell, thereby reducing the risk that the foreign matter generated by the bare battery cell enters the first through hole and then contacts the shell after passing through the first through hole and the second through hole, and helping to improve the electrical performance and safety of the battery.

[0016] In addition, the insulating layer prevents solid foreign matter from entering the first through hole, and the gap between the insulating layer and the insulating film can also communicate with the first through hole and the second through hole to form a diffusion channel of the electrolyte, so that the electrolyte quickly flows from the shell to the bare battery through the diffusion channel, which is more friendly to the entry of free electrolyte into the interior of the bare battery. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present application or related art, the following will briefly introduce the drawings needed to be used in the embodiments or related art description. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0018] Figure 1 The insulating film of the battery of the embodiment of the present application is shown in the schematic diagram.

[0019] Figure 2 The bottom support plate of the battery of the embodiment of the present application is shown in the schematic diagram.

[0020] Figure 3 The partial front view schematic diagram of the battery of the first structure of the embodiment of the present application is shown in the schematic diagram.

[0021] Figure 4 The partial front view schematic diagram of the battery of the first structure of the embodiment of the present application is shown in the schematic diagram. Figure 3 The cross-sectional schematic diagram of the middle A-A section is shown in the schematic diagram.

[0022] Figure 5 The partial front view schematic diagram of the battery of the first structure of the embodiment of the present application is shown in the schematic diagram.

[0023] Figure 6 The partial front view schematic diagram of the battery of the first structure of the embodiment of the present application is shown in the schematic diagram.

[0024] Figure 7 The partial front view schematic diagram of the battery of the first structure of the embodiment of the present application is shown in the schematic diagram.

[0025] Figure 8 The partial front view schematic diagram of the battery of the first structure of the embodiment of the present application is shown in the schematic diagram.

[0026] Explanation of reference signs:

[0027] 100, insulating film; 110, first through hole; 120, bottom area;

[0028] 200, bottom support plate; 210, second through hole;

[0029] 300, bare cell; 310, bottom surface; 320, side surface; 330, side end surface; 340, top surface; 350, separator; 351, separator opening; 352, first surface; 353, second surface; 360, negative electrode tab; 370, positive electrode tab; 380, first space; 390, second space;

[0030] 400, insulating layer; 410, first region; 420, second region;

[0031] 510, positive electrode tab; 520, negative electrode tab;

[0032] 600, through-hole projection; 700, housing. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0034] It should be noted that the relative arrangement of the components, numerical expressions and values set forth in these embodiments are not limiting to the scope of the present application unless specifically stated otherwise.

[0035] It should be understood that the dimensions of the various parts shown in the drawings are not necessarily drawn to scale.

[0036] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way limiting to the scope of the application or its applications or uses.

[0037] It should be noted that 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 unless otherwise defined. The terms "first", "second" and the like used in the embodiments of the present application do not represent any order, number or importance, but are only used to distinguish different components. The terms "include" or "contain" and the like 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 "connected" or "connected" and the like are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms "up", "down", "left", "right" and the like are only used to represent relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0038] In the battery, the insulating film 100 is wrapped outside the bare battery cell 300, and plays a role of insulation for the bare battery cell 300 and the metal shell 700 (for example, an aluminum shell) of the battery, so as to avoid corrosion of the shell 700 due to the overlap of the bare battery cell 300 (for example, the negative electrode sheet 360 in the bare battery cell 300) and the shell 700.

[0039] Figure 1 A schematic view showing the unfolded state of the insulating film 100 of the first structure is shown as Figure 1 The insulating film 100 has a bottom region 120 corresponding to the bottom support plate 200, and a first through hole 110 penetrating the insulating film 100 is arranged in the bottom region 120.

[0040] Figure 2 A schematic view showing the bottom support plate 200 is shown as Figure 2 A second through hole 210 corresponding to the first through hole 110 and penetrating the bottom support plate 200 is arranged on the bottom support plate 200.

[0041] As Figure 3 , Figure 3 A partial front view schematic view of the battery of the first structure is shown, in which the bottom support plate 200 is arranged on the side of the insulating film 100 away from the bare battery cell 300 and is attached to the bottom region 120 of the insulating film 100, and the first through hole 110 and the second through hole 210 are in communication. For example, the orthographic projection of the second through hole 210 on the insulating film 100 can coincide with the first through hole 110, that is, the first through hole 110 and the second through hole 210 have the same aperture, and when the first through hole 110 and the second through hole 210 are in communication, they are coaxial.

[0042] During the movement or assembly of the bare battery cell 300, foreign matter (for example, active material debris of the electrode sheet) may be separated out. Since one end of the first through hole 110 faces the bare battery cell 300, the foreign matter can enter the first through hole 110 through this end, and then stay in the first through hole 110 or sequentially pass through the first through hole 110 and the second through hole 210 to contact the shell 700, causing corrosion of the shell 700. There is also a risk that the bare battery cell 300 will be overlapped with the shell 100 through the foreign matter.

[0043] In order to solve the above problems, as Figure 3 The battery provided by the embodiments of the present application comprises: a bare battery cell 300; an insulating film 100 wrapped outside the bare battery cell 300, the insulating film 100 being provided with a first through hole 110; a bottom support plate 200 arranged on the side of the insulating film 100 away from the bare battery cell 300, the bottom support plate 200 being provided with a second through hole 210, and the second through hole 210 being in communication with the first through hole 110; and an insulating layer 400 arranged between the bare battery cell 300 and the insulating film 100. Figure 5This shows a partial bottom-view schematic diagram of the battery with the first structure, such as... Figure 3 and Figure 5 Along the axial direction of the first through hole 110 (e.g.) Figure 3 In the Z direction, the orthographic projection of the first through hole 110 on the bare cell 300 is the through hole projection 600, and the orthographic projection of the insulating layer 400 on the bare cell 300 is the layer projection. The through hole projection 600 and the layer projection at least partially overlap.

[0044] For example, the insulating layer 400 may be attached to the bare cell 300 or the insulating film 100.

[0045] For example, the insulating layer 400 can be connected to the bare cell 300 or the insulating film 100 by means of bonding or heat fusion.

[0046] In this embodiment, the layer projection at least partially overlaps with the through-hole projection 600. The insulating layer 400 can block at least part of the first through-hole 110 to reduce the opening area of ​​the first through-hole 110 near the bare cell 300, thereby reducing the risk that foreign objects falling from the bare cell 300 will enter the first through-hole 110 and come into contact with the housing 700 after passing through the first through-hole 110 and the second through-hole 210.

[0047] Furthermore, when there is a gap between the insulating layer 400 and the insulating film 100, the gap can connect with the first through hole 110 and the second through hole 210, thereby forming a small passage between the bare cell 300 and the casing 700. This small passage can block solid substances such as foreign objects from passing through, while allowing liquids such as electrolytes to pass through, thus enabling the electrolyte to enter the bare cell 300 more smoothly.

[0048] The battery provided in this application embodiment can at least partially block the first through hole 110 on the insulating film 100 through the insulating layer 400, thereby reducing the opening area of ​​the first through hole 110 near the bare cell 300. This reduces the risk of foreign objects generated by the bare cell 300 entering the first through hole 110 and coming into contact with the casing 700 after passing through the first through hole 110 and the second through hole 210, which helps to improve the electrical performance and safety of the battery.

[0049] In addition, while preventing solid foreign objects from entering the first through hole 110, the gap between the insulating layer 400 and the insulating film 100 can also connect with the first through hole 110 and the second through hole 210 to form a diffusion channel for the electrolyte. This allows the electrolyte to flow quickly from the housing 700 to the bare cell 300 through the diffusion channel, which is beneficial for free electrolyte to enter the interior of the bare cell 300.

[0050] like Figure 4 , Figure 4 Showing Figure 3A-A cross-sectional view, in some embodiments, the thickness of the insulation layer 400 is h, 30 pm≤h≤50 pm; the total thickness of the insulation film 100 and the bottom support plate 200 is H, 0.4 mm≤H≤0.7 mm.

[0051] For example, the thickness h of the insulation layer 400 can be 30 pm, 35 pm, 40 pm, 45 pm or 50 pm.

[0052] For example, the total thickness H of the insulation film 100 and the bottom support plate 200 can be 0.4 mm, 0.5 mm, 0.6 mm or 0.7 mm.

[0053] For example, the thickness of the insulation film 100 can be 0.1 mm to 0.2 mm.

[0054] For example, the thickness of the bottom support plate 200 can be 0.3 mm to 0.5 mm.

[0055] If the thickness of the insulation layer 400 is too small, the strength of the insulation layer 400 may be low, and the insulation layer 400 may be pierced by foreign matter, and the first through hole 110 cannot be reliably shielded. If the thickness of the insulation layer 400 is large, it will occupy more internal space of the shell 700, causing the energy density of the battery to decrease. Therefore, the thickness h of the insulation layer 400 is limited in this embodiment, which can not only ensure that the insulation layer 400 reliably shields the first through hole 110, but also make the battery have a higher energy density.

[0056] At the same time, the insulation film 100 and the bottom support plate 200 can support the bare battery cell 300. Specifically, it is difficult to form a right angle between the bottom plate and the side plate of the shell 700, and a fillet with a certain bending radius is usually formed. If the total thickness of the insulation film 100 and the bottom support plate 200 is too small, when the bare battery cell 300 is not cut, the bottom corner of the bare battery cell 300 may interfere with the fillet of the shell 700; and cutting the bare battery cell 300 may reduce the electrical performance of the bare battery cell 300. If the total thickness of the insulation film 100 and the bottom support plate 200 is too large, although the bottom of the bare battery cell 300 can be supported to a position higher than the fillet, the height of the bare battery cell 300 will also be reduced to avoid interference with the top cover of the battery. Therefore, the total thickness H of the insulation film 100 and the bottom support plate 200 is limited in this embodiment, which can not only prevent the bare battery cell 300 from interfering with the shell 700 without cutting the corner, but also make the height of the bare battery cell 300 higher, thereby having better electrical performance.

[0057] For example, the thickness of the insulation film 100 can be 0.1 mm to 0.2 mm. Figure 5 In some embodiments, the through hole projection 600 is located within the layer projection.

[0058] In the embodiment, since the layer projection completely covers the through-hole projection 600, the insulating layer 400 can comprehensively shield the first through-hole 110, so as to further reduce the risk of foreign matters generated by the bare battery cell 300 entering the first through-hole 110.

[0059] For example, Figure 5 In some embodiments, the minimum distance between the edge of the through-hole projection 600 and the edge of the layer projection is d, and d≥5 mm.

[0060] For example, the through-hole projection 600 is aligned with the center of the layer projection.

[0061] Generally, the insulating film 100 is provided with two first through-holes 110 in the bottom region 120, and the two first through-holes 110 are arranged at intervals along the second direction (for example, the X direction in Figure 1 Generally, the minimum distance between the edge of the through-hole projection 600 and the edge of the layer projection is the distance between the two along the second direction.

[0062] If d is small, when the insulating layer 400 and the insulating film 100 move relatively during the assembly of the battery or the use of the battery, the comprehensive shielding effect of the insulating layer 400 on the first through-hole 110 may be lost. Therefore, the embodiment limits d, so as to ensure that the insulating layer 400 can reliably and comprehensively shield the first through-hole 110, so as to further reduce the risk of foreign matters generated by the bare battery cell 300 entering the first through-hole 110.

[0063] Figure 6 Part of the battery is shown in a perspective view, for example, Figure 4 , Figure 5 and Figure 6 In some embodiments, the insulating layer 400 comprises an insulating substrate connected to the bare battery cell 300 through an adhesive layer; the bare battery cell 300 comprises a bottom surface 310 close to the bottom support plate 200, and two side surfaces 320 arranged opposite to each other along a first direction (for example, the Y direction in Figure 4 and Figure 6 The two side surfaces 320 are respectively connected to the bottom surface 310; the insulating layer 400 extends along the first direction, and comprises a first region 410 and a second region 420 located on at least one side of the first region 410 along the first direction; the first region 410 corresponds to the bottom surface 310, and the second region 420 is connected to the side surface 320; along the axial direction of the first through-hole 110, the orthographic projection of the first region 410 on the bottom surface 310 forms a layer projection, and the orthographic projection of the first through-hole 110 on the bottom surface 310 forms a through-hole projection 600.

[0064] For example, the first direction and the second direction are perpendicular to each other, and the first direction can be the length direction of the insulating layer 400, and the second direction can be the width direction of the insulating layer 400.

[0065] Exemplarily, the insulation layer 400 can be an insulation tape.

[0066] Exemplarily, the first area 410 of the insulation layer 400 can have a gap with the bottom surface 310.

[0067] Exemplarily, the first area 410 and the second area 420 of the insulation layer 400 are continuous and integrally formed.

[0068] In the embodiment, the insulation layer 400 is bonded to the surface of the bare battery cell 300. Specifically, the first area 410 can shield the first through hole 110, so as to avoid foreign matters generated by the bare battery cell 300 from entering the first through hole 110 from the bottom surface 310. The second area 420 is bonded to the side surface 320 of the bare battery cell 300 with a large area, so that the insulation layer 400 and the bare battery cell 300 have a large bonding area, so as to ensure the connection reliability between the two.

[0069] As shown in FIG. 4A, Figure 4 and Figure 6 In some embodiments, the second area 420 has a dimension L along the extension direction of the insulation layer 400, and L≥20 mm.

[0070] When the insulation layer 400 is connected to the bare battery cell 300 only through the second area 420, if L is small, in order to make the bonding area of the insulation layer 400 and the bare battery cell 300 meet the process requirements, the overall width of the insulation layer 400 needs to be large. If the width of the insulation layer 400 is too large, on the one hand, it will increase the material consumption of the insulation layer 400, so that the cost of setting the insulation layer 400 is high; on the other hand, it will also make the insulation layer 400 cover a large area of the bare battery cell 300, so that it is difficult for the electrolyte to enter the inside of the bare battery cell 300, affecting the infiltration rate of the electrolyte.

[0071] Therefore, the embodiment limits the extension length L of the second area 420, which can further ensure that the bonding area between the insulation layer 400 and the bare battery cell 300 meets the process requirements and guarantees the connection reliability between the two; on the other hand, it can also avoid the adverse effects on the infiltration rate of the electrolyte due to the too large width of the insulation layer 400.

[0072] Figure 7 A partial bottom view of a battery with a second structure is shown as follows, Figure 5 and Figure 7 In some embodiments, the bare battery cell 300 includes a plurality of positive electrode sheets 370 and a plurality of negative electrode sheets 360 arranged alternately along a first direction, and a diaphragm 350 separating the positive electrode sheets 370 and the negative electrode sheets 360; the diaphragm 350 is formed with a diaphragm opening 351 exposing the positive electrode sheet 370 and / or the negative electrode sheet 360 on the bottom surface 310.

[0073] For example, the bare battery cell 300 can be a stacked structure; or, as Figure 5 For example, the bare battery cell 300 can be a stacked structure; or, as Figure 7 For example, the bare battery cell 300 can be a stacked structure; or, as

[0074] It should be noted that in the embodiment of the present application, the diaphragm 350 is in a spiral winding structure or a Z-shaped (or serpentine) folding structure on the bottom surface 310 of the bare battery cell 300, and there is a space between two adjacent diaphragm 350 in the first direction, which contains the positive plate 370 or the negative plate 360, and the space forms a diaphragm opening 351 on the bottom surface 310, and the positive plate 170 or the negative plate 160 in the space is exposed through the diaphragm opening 351.

[0075] In combination with the foregoing, the gap between the first area 410 of the insulating layer 400 and the insulating film 100 is used to form a diffusion channel for the electrolyte, and the first area 410 corresponds to the bottom surface 310. The diaphragm 350 of the embodiment forms the diaphragm opening 351 on the bottom surface 310, so that the electrolyte can flow into the inside of the bare battery cell 300 through the diaphragm opening 351 after flowing out of the gap between the first area 410 and the insulating film 100, which helps to further improve the infiltration efficiency of the electrolyte.

[0076] For example, in some embodiments, the end of the diaphragm 350 extends to the side of the bare battery cell 300 close to the bottom support plate 200, and the surface of the end close to the bottom support plate 200 forms the bottom surface 310. Figure 4

[0077] For example, when the bare battery cell 300 is a stacked structure, the end of the diaphragm 350 can be the starting end or the ending end of the diaphragm 350.

[0078] For example, when the bare battery cell 300 is a stacked structure, the end of the diaphragm 350 can be the starting end or the ending end of the diaphragm 350.

[0079] In the embodiment, when the surface of the end of the diaphragm 350 close to the bottom support plate 200 forms the bottom surface 310, the end of the diaphragm 350 can be superimposed with the insulating layer 400, thereby shielding the first through hole 110 together with the insulating layer 400, improving the reliability of the insulating layer 400 shielding the first through hole 110, and further reducing the risk of the insulating layer 400 being pierced by foreign matter.

[0080] For example, in some embodiments, the end of the diaphragm 350 extends to the side of the bare battery cell 300 close to the bottom support plate 200, and the surface of the end close to the bottom support plate 200 forms the bottom surface 310. Figure 4 and Figure 5 ​In some embodiments, the bare cell 300 is a jelly-roll structure, and the separator 350 is folded in a "Z" shape to form a plurality of insertion spaces, the plurality of insertion spaces including first spaces 380 and second spaces 390 arranged alternately along the first direction, the positive electrode sheets 370 being inserted into the first spaces 380, and the negative electrode sheets 360 being inserted into the second spaces 390, the first spaces 380 and / or the second spaces 390 forming the separator openings 351 at the openings of the bottom surface 310.

[0081] For example, Figure 3 and Figure 5 The bare cell 300 further includes two side end surfaces 330 arranged oppositely along the second direction. When the bare cell 300 is a jelly-roll structure, each of the positive electrode sheets 370 has a portion extending out of the first space 380 at the opening of the side end surface 330, and the extending portions of the plurality of positive electrode sheets 370 are laminated to form the positive electrode tab 510. Similarly, each of the negative electrode sheets 360 has a portion extending out of the second space 390 at the opening of the side end surface 330, and the extending portions of the plurality of negative electrode sheets 360 are laminated to form the negative electrode tab 520.

[0082] When the bare cell 300 is a jelly-roll structure, the first region 510 of the insulating layer 400 can shield the separator openings 351 of the jelly-roll structure at the bottom surface 310, so as to prevent foreign matters generated by the bare cell 300 from entering the first through hole 110 through the separator openings 351 at the bottom surface 310. Meanwhile, after the electrolyte flows out of the gap between the first region 410 and the insulating layer 100, the electrolyte can quickly flow into the interior of the bare cell 300 through the separator openings 351, which helps to further improve the electrolyte infiltration efficiency.

[0083] For example, Figure 7 In some embodiments, the bare cell 300 is a jelly-roll structure, and the separator 350 includes a first surface 352 and a second surface 353 arranged oppositely, the plurality of positive electrode sheets 370 being connected to the first surface 352, and the plurality of negative electrode sheets 360 being connected to the second surface 353, the separator 350 being wound to form the jelly-roll structure, and the end of the jelly-roll structure along the winding axis forming the bottom surface 310, and the openings between the adjacent two turns of the separator 350 at the bottom surface 310 forming the separator openings 351.

[0084] For example, the plurality of positive electrode sheets 370 at the first surface 352 are arranged in a single direction (for example, the second direction) and are formed as an integral structure. The plurality of negative electrode sheets 360 at the second surface 353 are arranged in the same direction and are formed as an integral structure.

[0085] For example, Figure 8 A partial front view schematic diagram of a battery of a second structure is shown in FIG. 6. As shown in FIG. 6, Figure 7 and Figure 8The bare battery cell 300 also includes a top surface 340 opposite the bottom surface 310. When the bare battery cell 300 is in a wound structure, the two adjacent jelly-roll layers of the top surface 340 also have openings between the two adjacent jelly-roll layers of the top surface 340. Each of the positive electrode tabs 370 has a portion extending out of a portion of the openings of the top surface 340, and the extended portions of the plurality of positive electrode tabs 370 are laminated to form the positive electrode tab 510. Similarly, each of the negative electrode tabs 360 has a portion extending out of another portion of the openings of the top surface 340, and the extended portions of the plurality of negative electrode tabs 360 are laminated to form the negative electrode tab 520.

[0086] When the bare battery cell 300 is in a wound structure, the first region 410 of the insulating layer 400 can shield the jelly-roll openings 351 of the wound structure located at the bottom surface 310, so as to prevent foreign matters generated by the bare battery cell 300 from entering the first through hole 110 through the jelly-roll openings 351 of the bottom surface 310. Meanwhile, after the electrolyte flows out of the gap between the first region 410 and the insulating film 100, the electrolyte can quickly flow into the inside of the bare battery cell 300 through the jelly-roll openings 351, which is helpful to further improve the impregnation efficiency of the electrolyte.

[0087] It should be noted that when the positive electrode tab 510 and the negative electrode tab 520 are located at the top surface 340 of the bare battery cell 300, the insulating film 100 covers the bottom surface 310, the two side surfaces 320 and the two side end surfaces 330 of the bare battery cell 300, so that the positive electrode tab 510 and the negative electrode tab 520 are exposed.

[0088] When the positive electrode tab 510 and the negative electrode tab 520 are located at the side end surface 330 of the bare battery cell 300, the insulating film 100 covers the bottom surface 310, the top surface 340 and the two side surfaces 320 of the bare battery cell 300, so that the positive electrode tab 510 and the negative electrode tab 520 are exposed.

[0089] Regardless of which structure is adopted by the battery, the insulating layer 400 of the present embodiment can effectively shield the first through hole 110, and the versatility of the insulating layer 400 is relatively strong.

[0090] It should be noted that the above describes some embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the acts or steps recited in the claims can be performed in a different order than those described above and still achieve desirable results. Also, the processes depicted in the figures do not necessarily require the particular order shown or sequential order to achieve desirable results. In some implementations, multitasking and parallel processing can be advantageous.

[0091] Each of the embodiments in the present application is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be mutually referred to.

[0092] The description of the application is presented for purposes of illustration and description, and not by limitation. Numerous modifications and variations on the embodiments described herein will be apparent to those of ordinary skill in the art in light of the foregoing description. The embodiments described herein are chosen and described in order to best explain the principles of the application and its practical application to thereby enable others skilled in the art to best utilize the application. Various embodiments of the application are contemplated and can be made without departing from the spirit or scope of the application.

[0093] It should be understood that any of the above-described embodiments can be implemented in the form of control logic using hardware (e.g. an application specific integrated circuit or field programmable gate array) or a combination of hardware and software (e.g. software running on a processor or microprocessor). The software can be software stored in a computer readable storage medium such as RAM (random access memory) or ROM, for example, erasable programmable ROM, electrically erasable programmable ROM, flash memory or the like.

[0094] Although the application has been described in conjunction with specific embodiments thereof, numerous alternatives, modifications, and variations will be readily apparent to those of ordinary skill in the art. Such alternatives, modifications, and variations are intended to fall within the ambit of the present application.

[0095] It is intended that the application be construed as including all such alternatives, modifications and variations as fall within the scope of the present application. Accordingly, the application is not to be restricted except in accordance with the terms of the appended claims.

Claims

1. A battery, characterized by, The application relates to a battery cell, comprising: a bare cell; an insulating film covering the outer side of the bare cell, the insulating film being provided with a first through hole; a bottom support plate arranged on the side of the insulating film away from the bare cell, the bottom support plate being provided with a second through hole, the second through hole being in communication with the first through hole; an insulating layer arranged between the bare cell and the insulating film; along the axial direction of the first through hole, the orthographic projection of the first through hole on the bare cell is a through hole projection, the orthographic projection of the insulating layer on the bare cell is a layer projection, and the through hole projection and the layer projection at least partially overlap.

2. The battery of claim 1, wherein, The thickness of the insulating layer is h, 30 mu m<=h<=50 mu m; the total thickness of the insulating film and the bottom support plate is H, 0.4 mm<=H<=0.7 mm.

3. The battery of claim 1, wherein, The through hole projection is located in the layer projection.

4. The battery of claim 3, wherein, The minimum distance between the edge of the through hole projection and the edge of the layer projection is d, d>=5 mm.

5. The battery of claim 1, wherein, The insulating layer comprises an insulating substrate connected to the bare cell through an adhesive layer. The bare cell comprises a bottom surface close to the bottom support plate and two side surfaces oppositely arranged along a first direction, the two side surfaces being connected to the bottom surface respectively. The insulating layer extends along the first direction, the insulating layer comprises a first region and a second region located on at least one side of the first region along the first direction, the first region corresponds to the bottom surface, the second region is connected to the side surface, along the axial direction of the first through hole, the orthographic projection of the first region on the bottom surface forms the layer projection, and the orthographic projection of the first through hole on the bottom surface forms the through hole projection.

6. The battery of claim 5, wherein, The size of the second region along the extension direction of the insulating layer is L, L>=20 mm.

7. The battery of claim 5, wherein, The bare cell comprises a plurality of positive electrode sheets and a plurality of negative electrode sheets alternately arranged along the first direction, and a diaphragm separating the positive electrode sheets and the negative electrode sheets, the diaphragm is provided with a diaphragm opening exposing the positive electrode sheet and / or the negative electrode sheet on the bottom surface.

8. The battery of claim 7, wherein, The end of the diaphragm extends to the side of the bare cell close to the bottom support plate, and the surface of the end close to the bottom support plate forms the bottom surface.

9. The battery of claim 7, wherein, The bare cell is of a laminated structure, the diaphragm is folded in a "Z" shape to form a plurality of insertion spaces, the plurality of insertion spaces comprise first spaces and second spaces alternately arranged along the first direction, the positive electrode sheets are inserted into the first spaces, the negative electrode sheets are inserted into the second spaces, and the openings of the first spaces and / or the second spaces on the bottom surface form the diaphragm openings.

10. The battery of claim 7, wherein, The bare cell is of a winding structure, the diaphragm comprises a first surface and a second surface oppositely arranged, a plurality of the positive electrode sheets are connected to the first surface, a plurality of the negative electrode sheets are connected to the second surface, and the diaphragm is wound to form the winding structure; the end of the winding structure along the winding axis forms the bottom surface, and the openings between the adjacent two turns of the diaphragm on the bottom surface form the diaphragm openings.

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