Battery cell and battery
By setting an adhesive component to bond the separator in the first electrode area of the battery cell, the problem of electrode tearing and short circuit under external force is solved, which improves the safety performance of the battery and simplifies the production process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NINGDE AMPEREX TECHNOLOGY LTD
- Filing Date
- 2018-01-22
- Publication Date
- 2026-07-31
AI Technical Summary
When a battery is dropped or subjected to an external impact, the outer current collector of the battery cell is prone to tearing and wrinkling, resulting in burrs or sharp corners, which can lead to short circuit risks and affect the safety performance of the battery.
A first adhesive is provided in the first region of the first electrode of the battery cell to bond the first electrode and the separator together, preventing relative movement between the electrode and the separator and reducing the probability of electrode tearing. The first and second adhesives apply forces in different directions to counteract local forces and reduce the risk of electrode tearing.
It effectively reduces the probability of electrode tearing under external force, prevents short circuits, improves battery safety performance, simplifies production process and reduces costs.
Smart Images
Figure CN115663404B_ABST
Abstract
Description
[0001] This application is a divisional application of the original invention patent application (filed on January 22, 2018, application number 201810060923.4, invention title "Battery Cell and Battery"). Technical Field
[0002] This application relates to the field of electrochemical device technology, and more particularly to a battery cell and a battery having the same. Background Technology
[0003] Batteries, due to their portability, are widely used in various portable devices, such as mobile phones, laptops, power tools, and electric vehicles. Among battery performance metrics, safety is receiving increasing attention. If battery safety cannot be guaranteed, it can lead to serious accidents such as combustion and explosion. During drops or impacts, the outer current collector of the battery cell is prone to tearing, wrinkling, and other damage. Burrs or sharp edges may form on the current collector, potentially causing a short circuit hazard. Summary of the Invention
[0004] This application discloses a battery cell that has the advantages of simple structure and good safety performance.
[0005] This application also proposes a battery having cells as described above.
[0006] A battery cell according to an embodiment of this application includes: a first electrode, the first electrode including a first region, the first region not coated with a first active material, the first region being located inside the outermost ring of the battery cell; a separator; and a first adhesive member disposed between the first region and the separator, the first adhesive member being bonded to the first region and the separator.
[0007] According to the embodiments of this application, by providing a first adhesive in the first region of the first electrode, the first electrode and the separator can be bonded together by the first adhesive, preventing relative movement between the first electrode and the separator when the battery cell is subjected to external force (such as falling or impact), thereby effectively reducing the probability of the first electrode tearing, and thus effectively protecting the first electrode and preventing damage or short circuit of the battery cell due to tearing of the first electrode.
[0008] In some embodiments, the battery cell further includes a second electrode, and the separator is disposed between the first electrode and the second electrode.
[0009] In some embodiments, the first electrode is a cathode electrode and the second electrode is an anode electrode.
[0010] In some embodiments, the second electrode includes a second region that is not coated with the second active material, and the first region and the second region are directly opposite each other.
[0011] In some embodiments, the first electrode further includes a third region located outside the outermost ring of the cell; the cell further includes a second adhesive member bonded to the third region.
[0012] In some embodiments, the first adhesive and the second adhesive do not overlap at all.
[0013] In some embodiments, the first adhesive member and the second adhesive member at least partially overlap.
[0014] In some embodiments, the first adhesive and the second adhesive completely overlap.
[0015] In some embodiments, along the winding direction of the first electrode sheet, the length of the first adhesive is greater than or equal to the length of the second adhesive.
[0016] In some embodiments, the width of the first adhesive is greater than the width of the second adhesive in the width direction of the first electrode.
[0017] In some embodiments, both the first adhesive and the second adhesive are selected from adhesives, tapes, or double-sided tapes.
[0018] In some embodiments, the first electrode further includes a fourth region, which is not coated with the first active material and is directly opposite the first region.
[0019] In some embodiments, the length of the first adhesive member is 10-12 mm.
[0020] In some embodiments, the width of the first adhesive is 84-86 mm.
[0021] The battery according to an embodiment of this application includes a packaging shell and a battery cell as described above, wherein the battery cell is disposed within the packaging shell.
[0022] According to the battery embodiments of this application, by providing a first adhesive member in the first region of the first electrode, the first region of the first electrode and the separator can be bonded together using the first adhesive member. This prevents the battery cell from being subjected to external forces (such as drops or impacts), thus mitigating the impact force on the first region of the first electrode and effectively reducing the probability of the first electrode tearing. Consequently, the first electrode is effectively protected, preventing damage to the battery cell or short circuits caused by tearing of the first electrode. Furthermore, relative movement between the first region of the first electrode and the separator is prevented, preventing separator shrinkage and thus preventing short circuits in the battery cell. Attached Figure Description
[0023] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:
[0024] Figure 1 This is a schematic diagram of the structure of a battery cell according to an embodiment of this application, wherein a first adhesive layer is provided in the first region;
[0025] Figure 2 yes Figure 1 Front view of the first electrode of the battery cell;
[0026] Figure 3 yes Figure 2 A bottom view of the first electrode plate in the middle;
[0027] Figure 4 This is a schematic diagram of the structure of a battery cell according to an embodiment of this application;
[0028] Figure 5 yes Figure 4 A partially enlarged schematic diagram of the battery cell in the image;
[0029] Figure 6 This is a schematic diagram of the structure of a battery cell according to an embodiment of this application;
[0030] Figure 7 yes Figure 6 A partially enlarged schematic diagram of the battery cell in the image;
[0031] Figure 8 yes Figure 4 and Figure 6 Front view of the first electrode plate;
[0032] Figure 9 yes Figure 8 Top view of the first electrode plate;
[0033] Figures 10 to 13 This is a schematic diagram showing the positional relationship between the first adhesive component 130 and the second adhesive component 114.
[0034] Figure label:
[0035] Cell 100, uncoated area 150
[0036] First electrode 110, first region 111, first active material 112, third region 113, second adhesive 114, fourth region 115.
[0037] Diaphragm 120,
[0038] First adhesive component 130,
[0039] Second electrode 140, second region 141, second active substance 142. Detailed Implementation
[0040] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0041] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0042] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0043] The following is for reference. Figures 1-7 The battery cell 100 according to an embodiment of this application includes a first electrode 110, a separator 120, and a first adhesive 130.
[0044] Specifically, such as Figures 1 to 3 As shown, the first electrode 110 may include a first region 111, the first region 111 is not coated with the first active material 112, the first region 111 is located inside the outermost ring of the cell 100, and the first adhesive 130 is disposed between the first region 111 and the separator 120, and the first adhesive 130 is bonded to the first region 111 and the separator 120.
[0045] According to the embodiments of this application, the battery cell 100, by providing a first adhesive member 130 in the first region 111 of the first electrode 110, can bond the first electrode 110 and the separator 120 together using the first adhesive member 130. This can alleviate the impact force received by the first region 111 of the first electrode 110, thereby effectively reducing the probability of the first electrode 110 tearing at the first region 111. Assuming the first electrode 110 tears in the first region 111, burrs will be generated. These burrs can puncture the separator and short-circuit with the second electrode 140. During a drop or impact, the battery cell 100 may develop wrinkles in the uncoated current collector at the tail of the first electrode 110, creating sharp corners, which could also puncture the separator and short-circuit with the second electrode 140. Therefore, this embodiment provides the first adhesive member 130 in the first region 111, which can effectively protect the first electrode 110 and prevent damage or short circuits to the battery cell due to tearing of the first electrode 110. Furthermore, relative movement between the first region 111 of the first electrode 110 and the separator is prevented, thus preventing separator shrinkage and short circuit of the cell 100. It should be understood that the uncoated portion of the inner side of the tail end of the first electrode 110 is the first region 111, and the first adhesive 130 can be positioned at any location within the first region 111. Along the winding direction of the first electrode 110, the first adhesive 130 can be shorter than or equal to the length of the first region 111.
[0046] According to some embodiments of this application, such as Figures 1 to 3 As shown, the battery cell 100 may further include a second electrode 140, and a separator 120 is disposed between the first electrode 110 and the second electrode 140. It should be noted that the separator 120 may be an insulating component, which can separate the first electrode 110 and the second electrode 140 to prevent short circuits caused by contact between the first electrode 110 and the second electrode 140.
[0047] Furthermore, the first electrode 110 can be a cathode electrode, and the second electrode 140 can be an anode electrode. Even further, the first electrode 110 can be an electrode made of aluminum foil (AL foil) as the current collector, with a first active material 112 disposed on the aluminum foil; the second electrode 140 can be an electrode made of copper foil (CU foil) as the current collector, with a second active material 142 disposed on the copper foil. The first active material can be lithium iron phosphate, lithium cobalt oxide, or lithium manganese oxide, and the second active material can be graphite, etc.
[0048] like Figure 2 and Figure 3As shown, in this embodiment, the first electrode 110 is wound from one end to the other end along the winding direction indicated by arrow a. The first electrode 110 includes a current collector at its tail end that is not coated with active material. The current collector at the tail end includes a first region 111, and a first adhesive 130 is disposed in the first region 111. It should be noted that the first adhesive 130 can be bonded to the first region 111 before winding or after winding.
[0049] like Figure 4 As shown, in this embodiment, the second electrode 140 may include a second region 141, which is not coated with the second active material 142. The first region 111 and the second region 141 are opposite each other, meaning that the outermost region of the cell 100 includes an uncoated region 150, which is formed by the first region 111, the separator 120, and the second region 141. Since the first region 111 and the second region 141 belong to electrodes of different polarities, it is assumed that if the cell 100 is punctured from the uncoated region 150, it is a relatively safe short circuit. Therefore, the presence of the uncoated region 150 in this embodiment enhances the safety performance of the cell 100. Of course, in addition to having the outermost uncoated region 150, the cell 100 may also have an uncoated region 150 at its center.
[0050] like Figure 4 and Figure 6 As shown, in these embodiments, the first electrode 110 may further include a third region 113. The third region 113 is located outside the outermost ring of the cell 100, i.e., the first region 113 is located on the back side of the first region 111. The cell 100 may also include a second adhesive member 114, which is bonded to the third region 113. It should be noted that the second adhesive member 114 can be used to bond the cell 100 to the battery packaging shell (not shown). Bonding the cell 100 to the packaging shell can prevent relative movement between the cell 100 and the packaging shell. Since the first region 111 is bonded to the diaphragm 120 through the first adhesive 130, when the cell 100 is subjected to external force, the first adhesive 130 located in the first region 111 generates a force F1 on the first electrode 110, and the second adhesive 114 located in the third region generates a force F2 on the first electrode 110. These two forces are in opposite directions, and at least part of the force F1 can cancel each other out with the force F2, thereby reducing the probability of the first electrode 110 tearing due to excessive local force and effectively improving the safety performance of the cell 100.
[0051] Figure 5 yes Figure 4 A magnified view of a portion, such as Figure 5As shown, the first region 111 is the inner surface of the current collector at the tail of the first electrode 110, and the third region 113 is the outer surface of the current collector at the tail of the first electrode 110.
[0052] like Figure 6 As shown, in this embodiment, the first electrode 110 may further include a fourth region 115, which is not coated with the first active material 112. The fourth region 115 is opposite to the first region 111, that is, the fourth region 115 is located on the outer side of the penultimate turn of the first electrode 110. In other words, the outer side of the cell 100 includes an uncoated region 150, which is formed by the first region 111, the separator 120, and the fourth region 115. It should be noted that along the winding direction of the first electrode 110 (e.g., ... Figure 8 When winding the first electrode 110 in the direction indicated by the middle arrow a, the fourth region is wound first, and then the first region 111 is wound. The fourth region 115 is located in the inner circle of the first region 111, and the fourth region 115 is opposite to the first region 111. Figure 7 yes Figure 6 A magnified view of a section, from Figure 7 It can be seen that the fourth region 115 is a region of the first electrode 110, and is the outer surface of the current collector located in the inner ring of the first region 111.
[0053] like Figure 8 and Figure 9 As shown, in this embodiment, along the winding direction of the first electrode 110, i.e., the direction indicated by arrow a, it is wound from one end of the first electrode 110 and to the other end of the first electrode 110. The length of the first adhesive member 130 is greater than or equal to the length of the second adhesive member 114. It should be noted that, as Figure 8 As shown, the length direction of the first adhesive component 130 refers to the direction along which the adhesive component 130 extends. Figure 8 , Figure 9 The length dimension in the cc direction shown is the dimension along the winding direction of the first electrode 110. This further protects the first electrode 110 and prevents it from tearing due to uneven stress. Experiments have verified that when the length of the first adhesive 130 is 10-12 mm, it can better protect the first electrode 110.
[0054] like Figure 8 As shown, in this embodiment, in the width direction of the first electrode 110 (e.g., ... Figure 9 In the direction shown (bb), the width of the first adhesive 130 is greater than the width of the second adhesive 114. This further protects the first electrode 110 and prevents it from tearing due to uneven stress. Experiments have verified that when the width of the first adhesive 130 is 84-86 mm, it provides better protection for the first electrode 110.
[0055] According to some embodiments of this application, the first adhesive 130 can be selected from adhesive, tape, or double-sided adhesive. On one hand, the first adhesive 130 can be used to bond the diaphragm 120 and the first electrode 110 together, and the second adhesive 114 can be used to bond the first electrode 110 to other components (e.g., packaging shell). On the other hand, it can also simplify the manufacturing process and save production costs. According to some embodiments of this application, the second adhesive 114 can be selected from adhesive, tape, or double-sided adhesive.
[0056] The battery according to an embodiment of this application includes a packaging shell and a battery cell 100 as described above, the battery cell 100 being disposed inside the packaging shell. Inside the packaging shell, the battery cell 100 may or may not be adhered to the packaging shell by means of a second adhesive member 114.
[0057] In some embodiments, the first adhesive 130 may be double-sided tape, hot melt adhesive, or other similar adhesive tape or coating; in some embodiments, the second adhesive 114 may be double-sided tape, hot melt adhesive, or other similar adhesive tape or coating.
[0058] In some embodiments, the number of double-sided tape, hot melt adhesive, or other similar adhesive tapes or coatings is unlimited, and the shape can be rectangular, square, or other shapes.
[0059] In some embodiments, the cell can be used in a lithium-ion battery winding structure or in a stacked structure.
[0060] In some embodiments, the thickness of the first adhesive 130 and the second adhesive 114 is between 1u and 100u.
[0061] In some embodiments, double-sided tape, hot melt adhesive, or other similar adhesive tape or coating may completely or partially cover blank aluminum foil or copper foil.
[0062] like Figure 4 and Figure 6 As shown, the first adhesive member 130 and the second adhesive member 114 have exactly the same length and width, and they completely overlap. Figures 10 to 12 As shown, the first adhesive 130 and the second adhesive 114 may partially overlap.
[0063] like Figure 13 As shown, the first adhesive component 130 and the second adhesive component 114 may not overlap at all. Example:
[0064] Using commercially produced lithium cobalt oxide, graphite, electrolyte, separator, and packaging shell as raw materials, and employing a conventional winding structure, a lithium-ion battery with model number 495196 and a capacity of 4000mAh is manufactured.
[0065] The experimental procedure is as follows:
[0066] Comparison Group A: The outermost ring of the cell is the first electrode 110. The tail end of the first electrode 110 is a current collector that is not coated with the first active material 112. The first region 111 of the first electrode 110 is not provided with the first adhesive 130 (e.g., double-sided tape), and the third region 113 is not provided with the second adhesive 114 (e.g., double-sided tape).
[0067] Comparative Group B: The first region 111 of the first electrode 110 does not have a first adhesive 130 (e.g., double-sided tape), and the third region 113 has a second adhesive 114 (e.g., double-sided tape). The rest is the same as Comparative Group A.
[0068] Experimental Group C: The first region 111 of the first electrode 110 is provided with a first adhesive 130 (e.g., double-sided tape), and the third region 113 is provided with a second adhesive 114 (e.g., double-sided tape). The rest is the same as the control group A.
[0069] Experimental Group D: The first region 111 of the first electrode 110 is provided with a first adhesive 130 (e.g., double-sided tape), and the third region 113 is not provided with a second adhesive 114 (e.g., double-sided tape). Other aspects are the same as those of Control Group A.
[0070] The four groups of batteries, A, B, C, and D, were subjected to the following drop test:
[0071] Drop test conditions: Height: 1.5m;
[0072] The falling sequence is 6 sides + 4 corners for one round;
[0073] It fell a total of 6 times (60 times);
[0074] After the battery cells were disassembled after the fall, it was found that the A group of battery cells, due to the lack of double-sided adhesive, could move freely inside the packaging shell. The top and bottom of the anode and cathode plates were severely deformed due to the impact, and the outermost diaphragm showed signs of shrinkage.
[0075] Because the AL foil of Group B cells has double-sided adhesive on the outer layer, there is an interaction force between the cell and the packaging shell. There is no problem of electrode deformation or damage caused by impact at the top and bottom of the electrode, but there is obvious tearing of the empty AL foil.
[0076] Because the C-group cells have double-sided adhesive on both the inner and outer sides of the AL foil, the outer double-sided adhesive inhibits the free movement of the cell within the packaging during a drop, and there is no deformation of the top and bottom of the electrode due to impact. The double-sided adhesive on the inner side of the AL foil tightly bonds the AL foil and the inner separator together. Due to the certain toughness of the separator, the AL foil of the C-group cells does not tear and there is no shrinkage of the separator.
[0077] Because the D-group cells have no double-sided adhesive on the outer layer, there is no tearing of the Al foil. Because there is double-sided adhesive on the inside of the Al foil, the separator is stuck to the empty Al foil, and there is no separator shrinkage.
[0078] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0079] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.
Claims
1. A battery cell, flat in shape, comprising a straight section and a bent section, the battery cell comprising: The first electrode includes a first region, which is not coated with a first active material and is located inside the outermost ring of the battery cell. Diaphragm; A first adhesive is disposed between the first region and the diaphragm and located in the straight section; the first adhesive is bonded to the first region and the diaphragm respectively. The first electrode also includes a third region, which is located outside the outermost ring of the battery cell; The battery cell also includes a second adhesive component, which is bonded to the third region and the battery packaging shell respectively, and the second adhesive component is located in the straight section; The first adhesive and the second adhesive are respectively disposed on two surfaces of the current collector of the outermost ring of the battery cell and are positioned opposite each other. The first region and the third region are located in the same current collector layer of the outermost ring electrode of the battery cell. The first adhesive and the second adhesive partially overlap, and in the width direction of the first electrode, the two ends of the first adhesive extend beyond the two ends of the second adhesive.
2. The electric cell of claim 1, wherein, The first adhesive and / or the second adhesive are selected from double-sided adhesive or hot melt adhesive.
3. The electric cell of claim 1, wherein, The battery cell also includes a second electrode, and the separator is disposed between the first electrode and the second electrode.
4. The electric cell of claim 3, wherein, The first electrode is a cathode electrode, and the second electrode is an anode electrode.
5. The electric cell of claim 3, wherein, The second electrode includes a second region that is not coated with a second active material. The first region and the second region are opposite to each other. The cell includes an uncoated region formed by the first region, the separator, and the second region.
6. The electric cell of claim 1, wherein, The first adhesive component and the second adhesive component do not overlap at all.
7. The electric cell of claim 1, wherein, The first adhesive component and the second adhesive component completely overlap.
8. The electric cell of claim 1, wherein, Along the winding direction of the first electrode sheet, the length of the first adhesive component is greater than or equal to the length of the second adhesive component.
9. The electric cell of claim 1, wherein, In the width direction of the first electrode, the width of the first adhesive is greater than or equal to the width of the second adhesive.
10. The electric cell of claim 1, wherein, The first electrode also includes a fourth region, which is not coated with the first active material and is opposite to the first region.
11. The electric cell of claim 1, wherein, The length of the first adhesive component is 10-12 mm.
12. The electric cell of claim 1, wherein, The width of the first adhesive component is 84-86 mm.
13. A battery comprising a packaging shell and a battery cell as claimed in any one of claims 1 to 12, the battery cell being disposed within the packaging shell.