Battery and battery device
By adjusting the coverage area of the finishing tape, the problems of slow heat dissipation of the battery cell and damage to the diaphragm are solved, and the battery's good heat dissipation effect and structural stability are achieved, and safety is improved.
Patent Information
- Application Number
- CN202323328947.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-06
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2033-12-06
AI Technical Summary
The existing batteries have low thermal conductivity and excessive finishing tape area, which leads to slow heat dissipation of the battery cell, which increases the risk of thermal runaway. At the same time, the expansion stress of the steel shell leads to damage to the diaphragm.
By adjusting the ratio of the area of the side of the ending tape covering the battery cell to the side area, the thermal conductivity between the cell and the battery case is optimized, and the risk of damage to the ending tape and diaphragm is reduced.
It improves the thermal conductivity between the battery cell and the battery case, reduces the risk of damage to the finishing tape and diaphragm, improves the heat dissipation effect and structural stability of the battery, and enhances safety and stability.
Smart Images
Figure CN222300714U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to a battery and a battery device. Background Art
[0002] In the related art, the battery includes a battery housing and a wound cell located inside the battery housing, the battery housing includes steel, and the wound cell is wound with a finishing tape. However, the thermal conductivity of steel is relatively low, and the heat dissipation of the battery is slow. If the area of the finishing tape is relatively large, the finishing tape will affect the transfer of heat from the cell to the battery housing, thereby further increasing the risk of thermal runaway of the battery.
[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Utility Model Content
[0004] The utility model provides a battery, which can solve the technical problem of slow heat dissipation speed of a battery core body.
[0005] Battery Included:
[0006] A battery casing, the battery casing comprising steel;
[0007] A wound cell, the wound cell includes a cell body, the cell body is located in the battery housing, the cell body includes a positive electrode sheet, a negative electrode sheet, and a separator, part of the separator forms the outermost side of the cell body in the stacking direction of the positive electrode sheet and the negative electrode sheet, and the separator includes a winding tail end;
[0008] The tail tape is bonded to the winding tail end of the diaphragm and is used to fix the winding tail end of the diaphragm on the outer surface of the battery body;
[0009] The battery cell body includes a first side surface, which is the largest side surface of the battery cell body. At least part of the finishing tape is bonded to the first side surface, and the ratio of the area of the first side surface covered by the finishing tape to the area of the first side surface is 0.05-0.95.
[0010] In the utility model, the battery shell includes steel, and the thermal conductivity of steel is relatively poor, which will cause the battery to dissipate heat slowly. The ratio of the area covered by the tail tape to the area of the first side is too large, and the area covered by the tail tape is too large. The tail tape has a certain heat resistance, which leads to a slow heat conduction speed between the battery body and the battery shell; the ratio of the area covered by the tail tape to the area of the first side is too small, and the area covered by the tail tape is too small. At the same time, due to the good anti-expansion performance of the steel shell, when the battery body expands during charging and discharging, the distance between the battery body and the battery shell is too small, which easily leads to the damage of the tail tape. In addition, if there is more gas inside the battery, the steel shell will also expand, and the large expansion stress brought by the steel shell may cause damage to the diaphragm exposed to the outside in a large area. The utility model sets the ratio of the area covered by the tail tape to the area of the first side to a suitable size, which can not only improve the heat conduction speed between the battery body and the battery shell, but also reduce the risk of damage to the tail tape and the diaphragm.
[0011] The utility model also provides a battery device, which includes the above-mentioned battery. The battery has good heat dissipation effect and structural stability, so that the battery device also has good safety and stability.
[0012] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to better understand the present disclosure, reference may be made to the embodiments shown in the following drawings. The components in the drawings are not necessarily to scale, and related elements may be omitted in order to emphasize and clearly illustrate the technical features of the present disclosure. In addition, related elements or components may have different arrangements as known in the art. In addition, in the drawings, the same reference numerals represent the same or similar components in each drawing.
[0014] in:
[0015] Figure 1 is a schematic structural diagram of a battery in an exemplary embodiment of the present disclosure;
[0016] Figure 2 for Figure 1 A cross-sectional view of the battery shown along dashed line AA;
[0017] Figure 3 It is a schematic diagram of the structure of a single wound battery cell in an exemplary embodiment of the battery disclosed herein;
[0018] Figure 4 for Figure 3 A side view of the wound cell shown;
[0019] Figure 5 It is a schematic structural diagram of a single wound battery cell in another exemplary embodiment of the battery disclosed herein;
[0020] Figure 6 It is a schematic diagram of the structure of all wound cells in an exemplary embodiment of the battery disclosed in the present invention.
[0021] Description of reference numerals:
[0022] 1. Battery casing; 11. First side; 2. Wound battery cell; 21. Battery cell body; 211. First side; 212. Second side; 22. Tab; 3. Winding tail end; 4. Closing tape; 5. Insulating layer; 6. Core-closing tape. DETAILED DESCRIPTION
[0023] The following will be combined with the accompanying drawings in the exemplary embodiments of the present disclosure to clearly and completely describe the technical solutions in the exemplary embodiments of the present disclosure. The exemplary embodiments described herein are only for illustrative purposes and are not intended to limit the scope of protection of the present disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of the present disclosure.
[0024] In the description of the present disclosure, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; the term "plurality" refers to two or more; the term "and / or" includes any and all combinations of one or more associated listed items. In particular, reference to "the / the" object or "an" object is also intended to indicate one of a possible plurality of such objects.
[0025] Unless otherwise specified or explained, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.
[0026] Further, in the description of the present disclosure, it should be understood that the directional words such as "upper", "lower", "inner", "outer" and the like described in the exemplary embodiments of the present disclosure are described at the angles shown in the accompanying drawings and should not be understood as limitations on the exemplary embodiments of the present disclosure. It should also be understood that, in the context, when it is mentioned that an element or feature is connected to one or more "upper", "lower", or "inner", "outer" of another element, it can not only be directly connected to the "upper", "lower", "inner", "outer" of another element or elements, but can also be indirectly connected to the "upper", "lower", "inner", "outer" of another element or elements through an intermediate element.
[0027] In the description of the embodiments of the present application, the term "and / or" is merely a term used to describe the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone.
[0028] like Figure 1-4 As shown, Figure 1 is a schematic diagram of the structure of a battery in an exemplary embodiment of the present disclosure, Figure 2 for Figure 1 The battery is shown in a cross-sectional view along the dashed line AA, Figure 3 This is a schematic diagram of the structure of a single wound cell in an exemplary embodiment of the battery disclosed herein. Figure 4 for Figure 3 Side view of the wound cell shown.
[0029] The battery comprises: a battery shell 1, a wound battery cell 2, and a finishing tape 4, wherein the battery shell 1 comprises steel, for example, the battery shell 1 can be a steel shell; the wound battery cell 2 comprises a battery cell body 21, the battery cell body 21 is located in the battery shell 1, the battery cell body 21 comprises a positive electrode sheet, a negative electrode sheet, and a diaphragm, a portion of the diaphragm forms the outermost side surface of the battery cell body 21 in the stacking direction of the positive electrode sheet and the negative electrode sheet, and the diaphragm comprises a winding tail end 3; the finishing tape 4 is bonded to the winding tail end 3 of the diaphragm, and is used to fix the winding tail end 3 of the diaphragm on the outer surface of the battery cell body 21; wherein the battery cell body 21 comprises a first side surface 211, the first side surface 211 is the largest side surface of the battery cell body 21, at least a portion of the finishing tape 4 is bonded to the first side surface 211, and the ratio of the area of the first side surface 211 covered by the finishing tape 4 to the area of the first side surface 211 is 0.05-0.95. In this exemplary embodiment, the ratio of the area covered by the finishing tape 4 on the first side 211 to the area of the first side 211 is too large, the area covered by the finishing tape 4 on the first side 211 is too large, and the finishing tape 4 has a certain heat resistance, which leads to a slow heat conduction rate between the battery cell body 21 and the battery shell 1; the ratio of the area covered by the finishing tape 4 on the first side 211 to the area of the first side 211 is too small, and the area covered by the finishing tape 4 on the first side 211 is too small. At the same time, due to the good anti-expansion performance of the steel shell, when the battery cell body 21 expands during charging and discharging, the distance between the battery cell body 21 and the battery shell 1 is too small, which can easily cause the finishing tape 4 to be damaged. In addition, if there is a lot of gas inside the battery, the steel shell will also expand, and the large expansion stress brought by the steel shell may cause damage to the diaphragm with a large area exposed to the outside. In this exemplary embodiment, the ratio of the area of the first side surface 211 covered by the finishing tape 4 to the area of the first side surface 211 is set to a suitable size. This setting can not only improve the heat conduction rate between the battery cell body 21 and the battery casing 1, but also reduce the risk of damage to the finishing tape 4 and the diaphragm.
[0030] like Figure 1-4 As shown, the winding axis of the battery cell body 21 is the straight line direction parallel to the positive and negative electrode sheets when the positive and negative electrode sheets are wound. The battery cell body 21 may include a thickness direction Z, a height direction Y, and a length direction X. The battery cell body 21 may include two oppositely arranged curved side surfaces 213. The two curved side surfaces 213 are oppositely arranged in the length direction X of the battery cell body 21. The height direction Y of the battery cell body 21 is the winding axis of the battery cell body 21. The thickness direction Z, the height direction Y, and the length direction X of the battery cell body are perpendicular to each other, and the thickness of the battery cell body 21 is less than the length and height of the battery cell body 21. The first side surface 211 is connected between the two curved side surfaces 213.
[0031] In this exemplary embodiment, the ratio of the area of the first side 211 covered by the finishing tape 4 to the area of the first side 211 can be equal to 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, etc.
[0032] In this exemplary embodiment, Figure 1-4 As shown, the ratio of the dimension h1 of the finishing tape 4 in the axial direction of the winding of the battery cell body 21 to the dimension h2 of the battery cell body 21 in the axial direction of its winding is 0.05-1. For example, h1 / h2 can be equal to 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, etc. If h1 / h2 is too small, the closing tape 4 needs to have a larger width under the premise that the closing tape 4 covers the same area of the first side surface 11. When the wound cell 2 needs to be disassembled to recycle the pole piece, the closing tape 4 and the cell body 21 need to be separated first. However, since the closing tape 4 is relatively wide, it is difficult to separate the closing tape 4 and the cell body 21. If h1 / h2 is too large, the dimension h1 of the closing tape 4 in the winding axis of the cell body 21 is too large, and the heat dissipation of the cell body 21 is hindered, especially in the wound cell with the pole tab protruding, due to the large heat generated by the pole tab, h1 is too large, which will cause the heat of the cell body near the pole tab to be difficult to dissipate. In this exemplary embodiment, h1 / h2 is set to a suitable size, which can facilitate the disassembly of the wound cell 2 and the heat dissipation of the wound cell 2.
[0033] In this exemplary embodiment, Figure 1-4As shown, the wound battery cell 2 may further include a pole ear 22, which is disposed on one side of the battery cell body 21. For example, the pole ear 22 may be disposed on the top surface of the battery cell body 21. The distance h3 between the side of the battery cell body 21 provided with the pole ear 22 and the side of the tail tape 4 close to the pole ear 22 in the winding axial direction of the battery cell body 21 is greater than or equal to 0 and less than or equal to 100 mm. For example, h3 may be equal to 0, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, etc. Since the pole ear 22 generates a large amount of heat, if h3 is too small, the heat of the battery cell near the pole ear will not be easily dissipated; if h3 is too large, there is a risk of folding of the diaphragm winding tail end 3 near the pole ear 22, and the folding of the winding tail end 3 will cause the pole piece to be exposed outside the diaphragm, which may easily cause a short circuit between the pole piece and other structures such as the battery housing 1. In this exemplary embodiment, h3 is set to a suitable size, which can not only facilitate the heat dissipation of the wound battery cell 2, but also reduce the risk of folding of the diaphragm winding tail end 3.
[0034] like Figure 5 , which is a schematic diagram of the structure of a single wound cell in another exemplary embodiment of the battery disclosed herein. The cell body 21 may include two second side surfaces 212 arranged opposite to each other in the winding axis direction thereof, and the tail tape 4 partially extends to the second side surfaces 212. This arrangement can better protect the winding tail end 3 of the diaphragm through the tail tape 4, thereby preventing the winding tail end 3 of the diaphragm from being punched open and exposing the pole piece during the battery injection process.
[0035] like Figure 6As shown, it is a schematic diagram of the structure of all wound cells in an exemplary embodiment of the battery disclosed in the present invention. The battery may include a plurality of wound cells 2, and the plurality of wound cells 2 are distributed in the thickness direction Z of the cell body 21; the battery may also include: a core-sealing tape 6, the core-sealing tape 6 is at least partially bonded to the side surfaces of the plurality of cell bodies 21 on the same side, and the core-sealing tape 6 is used to fix the plurality of wound cells 2 into one. For example, the core-sealing tape 6 may at least partially be bonded to the curved side surfaces 213 of the plurality of cell bodies 21 on the same side, and a part of the structure of the core-sealing tape 6 may also be bonded to the first side surface 211 and the other side surface opposite to the first side surface 211. Among them, the minimum distance between the tail tape 4 and the core tape 6 can be greater than 0 and less than or equal to 150mm. For example, the minimum distance between the tail tape 4 and the core tape 6 can be equal to 1mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm, 105mm, 110mm, 115mm, 120mm, 125mm, 130mm, 135mm, 140mm, 145mm, 150mm, etc. The gap between the tail tape 4 and the core tape 6 can facilitate heat dissipation of the battery body 21. If the minimum distance between the end tape 4 and the core closing tape 6 is too small, it is not conducive to the heat dissipation of the battery cell body 21; if the minimum distance between the end tape 4 and the core closing tape 6 is too large, it is not conducive to the spatial arrangement of the core closing tape 6, which will cause the core closing tape 6 to be unable to fix the multiple wound battery cells 2 well. In this exemplary embodiment, the minimum distance between the end tape 4 and the core closing tape 6 is set to a suitable size, which can facilitate the heat dissipation of the battery cell body 21 and the arrangement of the core closing tape 6.
[0036] In this exemplary embodiment, Figure 6 As shown, the finishing tape 4 is located on the side of the battery cell body 21 facing the battery housing 1. This arrangement can facilitate heat dissipation from the battery cell body 21 to the battery housing 1.
[0037] It should be understood that in other exemplary embodiments, the finishing tape 4 can be disposed between opposite sides of adjacent battery cell bodies 21. This arrangement can make the side of the battery cell body 21 facing the battery housing 1 a flat side, and the side of the battery cell body 21 facing the battery housing 1 can be attached with an insulating layer, which can improve the flatness and bonding strength of the insulating layer.
[0038] In this exemplary embodiment, Figure 6As shown, the battery body 21 includes two second side surfaces 212 arranged opposite to each other in the winding axis direction thereof, and the two second side surfaces 212 respectively form the top surface and the bottom surface of the battery body 21. The battery may also include: a pole 7 and an insulating layer 5. The pole 7 is arranged on the battery shell 1, and the side wall of the battery shell 1 where the pole 7 is located is located on the side of the top surface of the battery body away from the bottom surface; the insulating layer 5 is bonded to the top surface of the battery body 21, and the insulating layer 5 can be used to insulate the battery body 21 and the adapter and other structures. The insulating layer 5 can cover at least part of the structure of the tail tape 4. This arrangement can strengthen the fixing strength of the tail tape 4 to the diaphragm winding tail end 3. The insulating layer 5 can be an insulating tape.
[0039] In this exemplary embodiment, Figure 1-6 As shown, the ratio of the thickness of the finishing tape 4 to the thickness of the diaphragm is 1-15, for example, the ratio of the thickness of the finishing tape 4 to the thickness of the diaphragm is equal to 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, etc. The ratio of the thickness of the tail tape 4 to the thickness of the diaphragm is too large, the thickness of the tail tape 4 is too large, and the thickness of the diaphragm is too small. If the thickness of the tail tape 4 is too large, the heat of the battery body 21 is difficult to transfer to the battery shell 1 through the tail tape 4. If the thickness of the diaphragm is too small, when the diaphragm contacts the battery shell, the diaphragm is easily damaged by the battery shell, which leads to problems such as leakage of the pole piece and powder falling off. The ratio of the thickness of the tail tape 4 to the thickness of the diaphragm is too small, the thickness of the tail tape 4 is too small, and the thickness of the diaphragm is too large. If the thickness of the tail tape 4 is too small, the tail tape 4 is easily damaged by the battery shell. If the thickness of the diaphragm is too large, the energy density of the battery body 21 is low. This exemplary embodiment sets the ratio of the thickness of the tail tape 4 to the thickness of the diaphragm to an appropriate size, which can reduce the risk of damage to the tail tape 4 and the diaphragm, and at the same time ensure the energy density of the battery body 21.
[0040] In this exemplary embodiment, the first side surface 211 and the side wall of the battery housing 1 are arranged opposite to each other, that is, the side surface of the battery body to which the tail tape 4 is attached is arranged opposite to the side wall of the battery housing 1. The thickness of the side wall opposite to the first side surface 211 in the battery housing 1 is 0.05mm-1.5mm, for example, the thickness of the side wall can be 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1mm, 1.05mm, 1.1mm, 1.15mm, 1.2mm, 1.25mm, 1.3mm, 1.35mm, 1.4mm, 1.45mm, 1.5mm, etc. If the thickness of the side wall of the battery housing 1 opposite to the first side 211 is too large, the weight of the battery is too large, and the space utilization rate of the battery is low; if the thickness of the side wall of the battery housing 1 opposite to the first side 211 is too small, the battery housing is easily deformed to form an angular structure, which is easy to damage the diaphragm and the tail tape 4. In this exemplary embodiment, the thickness of the side wall of the battery housing 1 opposite to the first side 211 is set to a suitable size, which can reduce the weight of the battery and improve the space utilization rate of the battery housing, and can also reduce the risk of damage to the diaphragm and the tail tape 4.
[0041] In this exemplary embodiment, the thickness of the side wall of the battery casing 1 opposite to the first side 211 may preferably be 0.075 mm-0.5 mm. For example, the thickness of the side wall of the battery casing 1 opposite to the first side 211 may be equal to 0.075 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, etc.
[0042] In this exemplary embodiment, Figure 1-6As shown, the bonding strength between the diaphragm and the finishing tape 4 is 0.1N / cm-5N / cm. For example, the bonding strength between the diaphragm and the finishing tape 4 can be equal to 0.1N / cm, 0.5N / cm, 1N / cm, 1.5N / cm, 2N / cm, 2.5N / cm, 3N / cm, 3.5N / cm, 4N / cm, 4.5N / cm, 5N / cm, etc. In this exemplary embodiment, the bonding strength between the diaphragm and the finishing tape 4 is set to a suitable size, which can reduce the risk of the diaphragm winding tail end 3 opening and also facilitate the disassembly of the wound battery cell. It should be noted that the bonding strength between the diaphragm and the finishing tape 4 defined in this exemplary embodiment can be the bonding strength between the diaphragm and the finishing tape 4 after the battery body 21 is infiltrated with the electrolyte. In addition, the bonding strength between the separator and the finishing tape 4 defined in this exemplary embodiment may also be the bonding strength between the separator and the finishing tape 4 before the cell body 21 is infiltrated by the electrolyte.
[0043] In this exemplary embodiment, Figure 1-6 As shown, the winding tail end 3 of the diaphragm can be located on the first side surface 211 , and the first side surface 211 has a larger area, so that this arrangement can facilitate the winding tail end 3 of the diaphragm to be fixed by the tail tape 4 .
[0044] In this exemplary embodiment, Figure 1-6 As shown, the battery is a quadrangular prism battery. A quadrangular prism battery mainly refers to a prism-shaped battery, but it is not strictly limited whether each side of the prism must be a straight line in the strict sense, and the corners between the sides are not necessarily right angles, and can be arc transitions.
[0045] In this exemplary embodiment, Figure 1-6As shown, the positive electrode sheet includes: a positive electrode current collector layer, a positive electrode active material layer, and the positive electrode active material layer is located on one side or both sides of the positive electrode current collector layer; the negative electrode sheet includes: a negative electrode current collector layer, a negative electrode active material layer, and the negative electrode active material layer is located on one side or both sides of the negative electrode current collector layer. The total thickness of the positive electrode active material layer on the positive electrode current collector layer can be 50μm-250μm, for example, the total thickness of the positive electrode active material layer can be equal to 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, 210μm, 220μm, 230μm, 240μm, 250μm, etc. And / or, the total thickness of the negative electrode active material layer on the negative electrode current collector layer can be 70μm-200μm, for example, the total thickness of the negative electrode active material layer can be 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, etc. If the total thickness of the positive electrode active material layer and the total thickness of the negative electrode active material layer are too large, the expansion amount of the battery body 21 during charging and discharging is too large, and the tail tape 4 is easily stretched; if the total thickness of the positive electrode active material layer and the total thickness of the negative electrode active material layer are too small, the thickness of the active material layer on the pole piece is too small, and the energy density of the battery is too small.
[0046] In this exemplary embodiment, the total thickness of the positive electrode active material layer and the total thickness of the negative electrode active material layer are set to a suitable size, which can ensure the energy density of the battery and reduce the risk of the finishing tape 4 falling off.
[0047] It should be noted that when the positive electrode active material layer is located on one side of the positive electrode current collector layer, the total thickness of the positive electrode active material layer on the positive electrode current collector layer is the thickness of the positive electrode active material layer on one side of the positive electrode current collector layer; when the positive electrode active material layer is located on both sides of the positive electrode current collector layer, the total thickness of the positive electrode active material layer on the positive electrode current collector layer is the thickness of the positive electrode active material layer on both sides of the positive electrode current collector layer. When the negative electrode active material layer is located on one side of the negative electrode current collector layer, the total thickness of the negative electrode active material layer on the negative electrode current collector layer is the thickness of the negative electrode active material layer on one side of the negative electrode current collector layer; when the negative electrode active material layer is located on both sides of the negative electrode current collector layer, the total thickness of the negative electrode active material layer on the negative electrode current collector layer is the thickness of the negative electrode active material layer on both sides of the negative electrode current collector layer.
[0048] In this exemplary embodiment, the negative electrode sheet includes a negative electrode active material layer, and the negative electrode active material layer can be natural graphite, artificial graphite, or doped silicon-based materials, and the silicon-based materials can be elemental silicon, silicon oxide, and silicon alloy. When the negative electrode active material layer includes a silicon-based material, the negative electrode active material layer containing the silicon-based material can increase the capacity of the battery. At the same time, the battery cell body 21 containing the silicon-based material expands greatly during charging and discharging, and the tail tape 4 is easily stretched. This exemplary embodiment can effectively reduce the risk of the tail tape 4 being stretched through the above scheme.
[0049] In this exemplary embodiment, the battery is any one of a lithium iron phosphate battery, a nickel cobalt manganese ternary battery, and a manganese iron lithium battery. The positive electrode active material layer in the lithium iron phosphate battery uses lithium iron phosphate as the main positive electrode material, and can also be doped with other materials such as nickel cobalt manganese, ternary materials, or manganese iron lithium materials. The positive electrode active material layer in the nickel cobalt manganese ternary battery uses nickel cobalt manganese ternary materials as the main positive electrode material, and can also be doped with other materials such as lithium iron phosphate, manganese iron lithium phosphate, etc. The positive electrode active material layer in the manganese iron lithium battery uses manganese iron lithium material as the main positive electrode material, and can also be doped with other materials such as lithium iron phosphate, ternary materials, etc.
[0050] In this exemplary embodiment, the positive electrode sheet includes a positive electrode collector and a positive electrode active material layer located on at least one side of the positive electrode collector, and the negative electrode sheet may include a negative electrode collector and a negative electrode active material layer located on at least one side of the negative electrode collector. The positive electrode active material of the lithium-ion battery may be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium iron manganese, etc. The negative electrode active material may be graphite, silicon, etc. The tabs include positive tabs and negative tabs, the positive tabs are connected to the positive electrode collector in the positive electrode sheet, for example, the positive tabs may be formed by cutting the positive electrode collector material layer; the negative tabs are connected to the negative electrode collector in the negative electrode sheet, for example, the negative tabs may be formed by cutting the negative electrode collector material layer. During charging, lithium ions are separated from the positive electrode active material, move to the negative electrode active material through the electrolyte, and the lithium ions are embedded in the negative electrode active material, completing the charging process of the battery. During discharging, lithium ions are separated from the negative electrode active material, move to the positive electrode active material through the electrolyte, and complete the discharging process of the battery.
[0051] The separator in the battery is used to separate the positive electrode and the negative electrode. The separator can allow ions to pass through while blocking electrons. The separator can be a polyethylene film, a polypropylene film, etc.
[0052] In this exemplary embodiment, the battery device is a battery module or a battery pack.
[0053] The battery module includes a plurality of batteries, and the batteries may be quadrangular prism batteries. The battery module may further include end plates and side plates, and the end plates and side plates are used to fix the plurality of batteries.
[0054] The battery pack includes a plurality of batteries and a box body, and the box body is used to fix the plurality of batteries.
[0055] It should be noted that the battery pack includes a battery, and the battery may be multiple, and the multiple batteries are arranged in the box. Among them, the multiple batteries can be installed in the box after forming a battery module. Alternatively, the multiple batteries can be directly arranged in the box, that is, there is no need to group the multiple batteries, and the box is used to fix the multiple batteries.
[0056] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing what is disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and embodiments are to be considered merely as exemplary, and the true scope and spirit of the present disclosure are indicated by the claims.
[0057] The drawings in the present disclosure only relate to the structures involved in the present disclosure, and other structures may refer to the usual design. In the absence of conflict, the embodiments of the present disclosure and the features in the embodiments may be combined with each other to obtain new embodiments. It should be understood by those of ordinary skill in the art that the technical solutions of the present disclosure may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present disclosure, and should be included in the scope of the claims of the present disclosure.
[0058] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.
Claims
1. A battery, characterized in that: The battery comprises: A battery housing (1), the battery housing (1) comprising steel; A wound battery cell (2), the wound battery cell (2) comprising a battery cell body (21), the battery cell body (21) being located in the battery housing (1), the battery cell body (21) comprising a positive electrode sheet, a negative electrode sheet, and a separator, a portion of the separator forming the outermost side of the battery cell body (21) in the stacking direction of the positive electrode sheet and the negative electrode sheet, and the separator comprising a winding tail end (3); A tail tape (4) is bonded to the winding tail end (3) of the diaphragm and is used to fix the winding tail end (3) of the diaphragm on the outer surface of the battery cell body (21); The battery cell body (21) comprises a first side surface (211), the first side surface (211) being the largest side surface of the battery cell body (21), at least a portion of the finishing tape (4) being bonded to the first side surface (211), and a ratio of an area of the first side surface (211) covered by the finishing tape (4) to an area of the first side surface (211) is 0.05-0.
95.
2. The battery according to claim 1, characterized in that The ratio of the thickness of the finishing tape (4) to the thickness of the diaphragm is 1-15.
3. The battery according to claim 1, characterized in that The first side surface (211) and the side wall of the battery housing (1) are arranged opposite to each other, and the thickness of the side wall of the battery housing (1) opposite to the first side surface (211) is 0.05 mm-1.5 mm.
4. The battery according to claim 3, characterized in that The thickness of the side wall of the battery housing (1) opposite to the first side surface (211) is 0.075 mm to 0.5 mm.
5. The battery according to claim 1, characterized in that The ratio of the dimension of the tail tape (4) in the winding axis direction of the battery cell body (21) to the dimension of the battery cell body (21) in the winding axis direction thereof is 0.05-1.
6. The battery according to claim 1, characterized in that The battery cell body (21) comprises two second side surfaces (212) arranged opposite to each other in the winding axis direction thereof, and the finishing tape (4) partially extends to the second side surfaces (212).
7. The battery according to claim 1, characterized in that The wound battery cell (2) further comprises a pole ear (22), wherein the pole ear (22) is arranged on one side of the battery cell body (21), and the battery cell body (21) is provided with a side of the pole ear (22) and a distance between a side of the finishing tape (4) close to the pole ear (22) in the winding axis direction of the battery cell body (21) that is greater than or equal to 0 and less than or equal to 100 mm.
8. The battery according to claim 1, characterized in that The battery cell body (21) comprises two second side surfaces (212) arranged opposite to each other in the winding axis direction thereof, the two second side surfaces (212) respectively forming the top surface and the bottom surface of the battery cell body (21), and the battery further comprises: A pole (7), the pole (7) being arranged on the battery housing (1), and a side wall of the battery housing (1) where the pole (7) is located is located on a side of the top surface away from the bottom surface; An insulating layer (5) is bonded to the top surface of the battery cell body (21), and the insulating layer (5) covers at least a portion of the structure of the finishing tape (4).
9. The battery according to any one of claims 1 to 8, characterized in that: The bonding strength between the diaphragm and the finishing tape (4) is 0.1 N / cm-5 N / cm.
10. The battery according to any one of claims 1 to 8, characterized in that: The battery is a quadrangular prism battery.
11. The battery according to any one of claims 1 to 8, characterized in that: The positive electrode sheet comprises: positive electrode current collector layer; A positive electrode active material layer, wherein the positive electrode active material layer is located on one side or both sides of the positive electrode current collector layer; The negative electrode sheet comprises: Anode current collector layer; A negative electrode active material layer, wherein the negative electrode active material layer is located on one side or both sides of the negative electrode current collector layer; The total thickness of the positive electrode active material layer on the positive electrode current collector layer is 50 μm-250 μm; And / or, the total thickness of the negative electrode active material layer on the negative electrode current collector layer is 70 μm-200 μm.
12. The battery according to any one of claims 1 to 8, characterized in that: The battery is any one of a lithium iron phosphate battery, a nickel cobalt manganese battery, and a manganese iron lithium battery.
13. The battery according to any one of claims 1 to 8, characterized in that: The winding tail end (3) of the diaphragm is located on the first side surface (211).
14. The battery according to any one of claims 1 to 8, characterized in that: The battery comprises a plurality of wound battery cells (2), wherein the plurality of wound battery cells (2) are distributed in the thickness direction of the battery cell body (21); The battery also includes: A core-sealing tape (6) is at least partially bonded to the side surfaces of the plurality of battery cell bodies (21) located on the same side, and the core-sealing tape (6) is used to fix the plurality of wound battery cells (2) into one body; Wherein, the minimum distance between the tail tape (4) and the core tape (6) is greater than 0 and less than or equal to 150 mm.
15. The battery according to any one of claims 1 to 8, characterized in that: The finishing tape (4) is located on a side of the battery cell body (21) facing the battery casing (1).
16. The battery according to any one of claims 1 to 8, characterized in that: The battery comprises a plurality of wound battery cells (2), wherein the plurality of wound battery cells (2) are distributed in the thickness direction of the battery cell body (21); The finishing tape (4) is arranged between opposite side surfaces of adjacent battery cell bodies (21).
17. A battery device, characterized in that: The battery device comprises the battery according to any one of claims 1-16.