WO2024055159A1

WO2024055159A1 - Battery cell, battery, and electric device

Info

Publication number: WO2024055159A1
Application number: PCT/CN2022/118480
Authority: WO
Inventors: 刘彦宇; 郑拓; 李川; 胥长龙; 林喆; 卓弘阳; 张磊
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2022-09-13
Filing date: 2022-09-13
Publication date: 2024-03-21

Abstract

The present application relates to a battery cell, a battery, and an electric device. The battery cell comprises: an electrode assembly, comprising a main body portion and a tab protruding from the main body portion, the tab having a bonding surface, the bonding surface being provided with a root area, a connection area, and a welding mark area, the root area being connected to the main body portion, and the connection area being connected between the root area and the welding mark area; and an insulating glue, having a glue applied surface, the glue applied surface being provided with a first glue applied area, a non-glue-applied area, and a second glue applied area that are continuously arranged in the width direction of the insulating glue, wherein the first glue applied area is bonded to the main body portion, the non-glue-applied area covers at least one of the root area and the connection area, and the second glue applied area is bonded to an adapter and the welding mark area. The battery cell, battery, and electric device provided in the present application can mitigate the problem of cracking of a tab of an electrode assembly under force, thereby improving the safety of the battery cell, battery, and electric device.

Description

Battery cells, batteries and electrical devices

Technical field

The present application relates to the field of battery technology, and in particular to a battery cell, a battery and an electrical device.

Background technique

Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

The battery includes a battery cell. There is an electrode assembly inside the battery cell. During the production and manufacturing process, in order to prevent the lug and the electrode assembly from being damaged due to false welding or leakage after welding of the electrode assembly's tabs and adapters or poles. The main parts overlap and cause safety accidents. Usually, after welding, insulating glue needs to be installed to bond the main part and the tabs, and the insulating glue completely covers the tabs.

Due to vibration and impact during the battery production process, the tabs are easily pulled by the insulating glue and cracked due to stress, resulting in increased internal resistance of the battery cells and reduced safety.

Contents of the invention

In view of the above problems, the present application provides a battery cell, a battery and an electrical device, which can alleviate the problem of cracking of the tabs of an electric electrode assembly due to force, thereby improving the safety of the battery cell, battery and electrical device.

In a first aspect, this application provides a battery cell, which includes:

The electrode assembly includes a main body and tabs protruding from the main body. The tabs have an adhesive surface. The adhesive surface has a root area, a connection area and a soldering area. The root area is connected to the main body, and the connection area is connected to the root area. and between the solder print area; and

Insulating glue has a glue-coated surface, and the glue-coated surface has a first glue-coated area, a non-glued area and a second glue-coated area continuously arranged along the width direction of the insulating glue;

The first glued area is bonded to the main body, the non-glued area covers at least one of the root area and the connection area, and the second glued area is bonded to the soldering area.

In this application, by setting the first glued area to be bonded to the main body, the second glued area to be bonded to the welding area, and the non-glued area to cover at least one of the root area and the connection area, due to the first The glued area, non-glued area and second glued area are arranged continuously, so the insulating glue can completely cover the tabs, and can fix and support each tab piece to prevent the tab piece from bending due to force and being separated from the main body. The internal overlap reduces the risk of short circuit inside the electrode assembly.

In one embodiment, the non-glued area covers the root area and the connecting area.

In this way, the root portion with the root area and the connection portion with the connection area are not easily pulled and torn by the insulating glue, so the safety of the battery cells, batteries and electrical devices can be ensured.

In one embodiment, the bonding surface further includes a head area, and the head area is arranged on the side of the soldering area away from the connection area; the second glue area is bonded to the head area.

By arranging the head area, a larger bonding area is provided between the insulating glue and the tab, thereby improving the reliability of the bonding between the tab and the main body. Furthermore, the insulating glue can hold the tabs more reliably to prevent the tabs from overlapping with the main body, making the battery safer.

In one embodiment, the main body includes a first surface with protruding tabs, and a second surface located in the thickness direction of the electrode assembly, and the second surface and the bonding surface are located on the same side of the electrode assembly; the first coating The glue area is bonded to the first surface and the second surface.

The first glue-coated area is bonded to the first surface and the second surface. Compared with the first glue-coated area being directly bonded to the first surface, the first glue-coated area is bonded to the main body in a larger area. The better the reliability of the connection and the wider the insulation coverage, the better the possibility of overlapping the tabs and the main body directly or indirectly through welding slag, so the safety of the battery cells, batteries and electrical devices is also The higher.

In one embodiment, the width of the first glue-coated area is W1, and the width of the first glue-coated area and the second surface is L1, and 2mm≤W1-L1.

By setting the width of the first glue coating area and the second surface to be L1, 2mm≤W1-L1, the bonding strength and insulation reliability of the insulating glue can be effectively improved, thereby ensuring that the battery cells have a better grounding safety.

In one embodiment, the width of the non-glued area is W2, the width of the first glued area and the first surface is L2, the width of the root area is L3, and the width of the connecting area is L4, 0mm<W1+ W2-L1-L2-L3-L4≤2mm.

By setting 0mm＜W1+W2-L1-L2-L3-L4≤2mm, the width of the insulating glue can be ensured to be large, and it can be firmly bonded to the main body, and has enough size to completely cover it. The root area and connection area help to better support the tabs and enhance the insulation effect between the tabs and the main body.

In one embodiment, there are two electrode assemblies and they are arranged side by side along the thickness direction of the electrode assemblies; the distance between the boundary lines of the soldering areas in the two electrode assemblies that are far away from each other is L5, W1+W2+W3<L1 +L2+L3+L4+L5.

By setting W1+W2+W3<L1+L2+L3+L4+L5, the insulating glue bonded to the positive tab in one of the electrode assemblies can be prevented from extending to the connection area of the positive tab in the other electrode assembly. And bonding with the connection area can also prevent the insulating glue bonded to the negative electrode tab in one electrode assembly from extending to the connection area of the negative electrode tab in the other electrode assembly and bonding with the connection area, thereby ensuring Covering the connection area is the non-glued area to prevent the tabs from being pulled and torn by the insulating glue, which helps to improve the safety of the battery and battery cells.

In one embodiment, the root area and the connection area are arranged at an angle, the angle between the root area and the connection area is A, and A satisfies the condition: A<90°.

By setting A, the condition is met: A<90°. Therefore, the operation root can be easily rotated relative to the connecting portion, which helps to improve the simplicity of battery cell assembly.

In one of the embodiments, an adapter is further included, and the adapter is provided on the side of the tab facing away from the bonding surface, and is connected to the area opposite the soldering area.

By providing an adapter, the electrical connection between the pole lug and the pole post can be facilitated.

In a second aspect, the present application provides a battery, which includes the battery cell as described in any of the above embodiments.

In a third aspect, the present application provides an electrical device, which includes the above-mentioned battery, which is used to provide electric energy, or includes the above-mentioned battery cell, which is used to provide electric energy.

The above description is only an overview of the technical solutions of the present application. In order to have a clearer understanding of the technical means of the present application, they can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable. , the specific implementation methods of the present application are specifically listed below.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the embodiments. The drawings are only for the purpose of illustrating the embodiments and are not to be considered as limitations of the application. Also, the same parts are represented by the same reference numerals throughout the drawings. In the attached picture:

Figure 1 is a schematic structural diagram of a vehicle in some embodiments of the present application;

Figure 2 is an exploded view of a battery in some embodiments of the present application;

Figure 3 is an exploded view of the battery cells after assembly in some embodiments of the present application;

Figure 4 shows how the electrode assemblies fit with the adapter, end caps and insulating glue when the main parts of the two electrode assemblies are spaced apart on opposite sides of the adapter before the battery cells are assembled in some embodiments of the present application. Schematic;

Figure 5 is a schematic diagram of the molding structure of the insulating glue after the insulating glue in the battery cell shown in Figure 4 is bonded to the tabs and adapters;

Figure 6 is a schematic diagram of the expansion of the insulating glue shown in Figure 5;

Figure 7 is a schematic structural diagram of the battery cell shown in Figure 4 with the insulating glue removed;

FIG. 8 is an enlarged schematic diagram of partial structure B of the battery cell shown in FIG. 7 .

Picture description:

1000. Vehicle; 100. Battery; 200. Controller; 300. Motor; 10. Box; 11. The first part; 12. The second part; 20. Battery cell; 21. Case; 22. Pole; 221 , positive pole; 222, negative pole; 23, end cap; 24, electrode assembly; 241, main body; 2411, first surface; 2412, second surface; 242, pole ear; 2421, positive pole ear; 2422, negative pole ear ; 2423. Adhesive surface; 24231. Root area; 24232. Connection area; 24233. Welding area; 24234. Head area; 24235. Welding area; 25. Adapter; 251. Positive adapter; 252. Negative electrode Adapter; 26, insulating glue; 261, glued surface; 2611, first glued area; 2612, non-glued area; 2613, second glued area.

Detailed ways

In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation modes of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described here. Those skilled in the art can make similar improvements without violating the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

In the description of this application, it needs to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " "Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inside", "Outside", "Clockwise", "Counterclockwise", "Axis" The orientation or positional relationship indicated by "radial direction", "circumferential direction", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply the device or device referred to. Elements must have a specific orientation, be constructed and operate in a specific orientation and therefore are not to be construed as limitations on the application.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

In this application, unless otherwise clearly stated and limited, the terms "installation", "connection", "connection", "fixing" and other terms should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection. , or integrated; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the connection of the inner areas of two elements or the interactive relationship between two elements, unless otherwise clear limits. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

In this application, unless otherwise expressly stated and limited, a first feature being "on" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediary. touch. Furthermore, the terms "above", "above" and "above" the first feature is above the second feature may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "below" and "beneath" the first feature to the second feature may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature has a smaller horizontal height than the second feature.

It should be noted that when an element is referred to as being "mounted" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is said to be "connected" to another element, it can be directly connected to the other element or there may also be intervening elements present. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation manner.

At present, judging from the development of the market situation, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydraulic, thermal, wind and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles and electric cars, as well as in many fields such as military equipment and aerospace. As battery application fields continue to expand, its market demand is also expanding.

The battery includes a battery cell, and an electrode assembly is provided inside the battery cell. The electrode assembly includes a main body and tabs protruding from the main body. The tabs are welded to adapters or poles. During the production and manufacturing process, in order to prevent the tabs of the electrode assembly from overlapping the main body of the electrode assembly due to false welding or missing welding after welding to the adapter or pole, and causing safety accidents, usually, during welding Finally, insulating glue needs to be installed to bond the main body and the tabs, and the insulating glue completely covers the tabs.

Among them, the pole tabs include several stacked pole tabs, and virtual welding means that the adapter or pole is welded to only a part of the pole tabs. In this way, the unsoldered tabs are easily bent relative to the main body and overlap with the main body, causing an internal short circuit in the electrode assembly. Missing welding refers to the sputtering of welding slag generated during the welding process to other areas other than the adapter or the area where the pole post and the tab are welded. After welding leakage, welding slag may overlap between the tab and the main body and cause an internal short circuit in the electrode assembly.

By setting insulating glue after welding to bond the main body and the tabs, and the insulating glue completely covers the tabs, each tab piece can be fixed and supported. In this way, the tabs can be avoided during vibration and impact. The sheet is bent under force and overlaps with the main body, which reduces the risk of short circuit inside the electrode assembly. In addition, the insulating glue can also seal the welding slag in the area where the adapter or pole is welded to the tab, so as to prevent welding slag from sputtering and overlapping between the tab and the main body. Moreover, even if the welding slag leaks, since the insulating glue completely covers the tab and has an insulating effect, it can prevent the welding slag from overlapping between the tab and the main body, thus further reducing the risk of short circuit inside the electrode assembly.

The applicant noticed that although the installation of insulating glue alleviated the problem of reduced safety caused by false soldering and missing soldering, due to the vibration and impact during the battery production process, the tabs were easily pulled by the insulating glue and stressed. Cracking will increase the internal resistance of the battery cells and reduce safety.

In order to alleviate the problem of the cracking of the tabs due to the pulling of the insulating glue, which causes the internal resistance of the battery cell to increase, the applicant conducted in-depth research and found that a battery cell was designed. The battery cell includes an electrode assembly and an insulating glue. The electrode assembly includes a main body. and a tab protruding from the main body. The tab has an adhesive surface. The adhesive surface has a root area, a connecting area and a soldering area. The root area is connected to the main body, and the connecting area is connected between the root area and the soldering area. The insulating glue has a glue-coated surface, and the glue-coated surface has a first glue-coated area, a non-glued area and a second glue-coated area continuously arranged along the width direction of the insulating glue, wherein the first glue-coated area is adhered to the main body. The non-glued area covers at least one of the root area and the connecting area, and the second glued area is bonded to the soldering area.

Among them, the part of the pole lug with the connecting area is adjacent to the soldering area. Affected by the soldering area, its mechanical strength is relatively weak and it is easy to crack under the pull of the insulating glue. Since the part of the pole lug with the root area is connected to the main body, the stress there is relatively concentrated and it is easy to crack under the pull of the insulating glue.

In such a battery cell, by arranging the first glued area to be bonded to the main body, the second glued area to be bonded to the soldering area, and the non-glued area to cover at least one of the root area and the connection area, Since the first glued area, non-glued area and second glued area are arranged continuously, the insulating glue can completely cover the tabs, and can fix and support each tab to avoid bending of the tabs due to force. And it overlaps with the main body, which reduces the risk of short circuit inside the electrode assembly. And the insulating glue also has an insulating effect. Even if the welding slag leaks, because the insulating glue completely covers the tab, it can also prevent the welding slag from overlapping between the tab and the main body. Therefore, the risk of short circuit inside the electrode assembly is further reduced. risk.

In addition, the non-glued area covers at least one of the root area and the connecting area. In this way, when there is a vibration impact, the root area and/or the connecting area covered by the non-glued area will no longer be pulled by the insulating glue, so that it can The root area and/or the connection area covered by the non-glued area are prevented from cracking, thus improving the safety of the battery cells.

Referring to FIG. 1 , the battery 100 disclosed in the embodiment of the present application can be used in, but is not limited to, vehicles 1000, ships, aircraft and other electrical devices. The power supply system of the electrical device can be composed of the battery 100 disclosed in the present application, which is beneficial to optimizing the safety performance of the battery cell 20 and the battery 100 .

Embodiments of the present application provide an electrical device that uses a battery 100 as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, spaceships, etc.

For the convenience of explanation in the following embodiments, an electric device 1000 according to an embodiment of the present application is used as an example.

The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The battery 100 is disposed inside the vehicle 1000 , and the battery 100 may be disposed at the bottom, head, or tail of the vehicle 1000 . Battery 100 may be used to power vehicle 1000 , for example, battery 100 may serve as an operating power source for vehicle 1000 . The vehicle 1000 may also include a controller 200 and a motor 300 . The controller 200 is used to control the battery 100 to provide power to the motor 300 , for example, for starting, navigating and driving the vehicle 1000 .

In some embodiments of the present application, the battery 100 can not only be used as an operating power source for the vehicle 1000 , but also can be used as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

Referring to FIG. 2 , the battery 100 includes a case 10 and a battery cell 20 . The box 10 is used to provide a storage space for the battery cells 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12 , the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a receiving cavity for accommodating the battery 100 . The second part 12 may be a hollow structure with one end open, and the first part 11 may be a plate-like structure. The first part 11 covers the open side of the second part 12 so that the first part 11 and the second part 12 jointly define a receiving cavity. ; The first part 11 and the second part 12 may also be hollow structures with one side open, and the open side of the first part 11 is covered with the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can be in various shapes, such as cylinder, rectangular parallelepiped, etc.

In the battery 100, there may be a plurality of battery cells 20, and the plurality of battery cells 20 may be connected in series, in parallel, or in mixed connection. Mixed connection means that the plurality of battery cells 20 are connected in series and in parallel. The plurality of battery cells 20 can be directly connected in series or in parallel or mixed together, and then the whole composed of the plurality of battery cells 20 can be accommodated in the box 10 ; of course, the battery 100 can also be a plurality of battery cells 20 First, the battery 100 modules are connected in series, parallel, or mixed to form a module form. Multiple battery 100 modules are then connected in series, parallel, or mixed to form a whole, and are accommodated in the box 10 . The battery 100 may also include other structures. For example, the battery 100 may further include a bus component for realizing electrical connections between multiple battery cells 20 .

Each battery cell 20 may be a secondary battery 100 or a primary battery 100; it may also be a lithium-sulfur battery 100, a sodium-ion battery 100 or a magnesium-ion battery 100, but is not limited thereto. The battery cell 20 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped or other shapes.

Please refer to FIGS. 3 , 4 , 5 and 6 together. The battery cell 20 refers to the smallest unit that constitutes the battery 100 . The battery cell 20 includes a casing 21, an end cover 23, an electrode assembly 24, an insulating glue 26 and other energy supply components.

The end cap 23 refers to a component that covers the opening of the case 21 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 23 can be adapted to the shape of the housing 21 to fit the housing 21 . Optionally, the end cap 23 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 23 is less likely to deform when subjected to extrusion and collision, so that the battery cell 20 can have higher durability. Structural strength and safety performance can also be improved. The end cap 23 can be provided with functional components such as the pole 22 and the like. The pole 22 may be used to electrically connect with the electrode assembly 24 for outputting or inputting electrical energy from the battery cell 20 . In some embodiments, the end cap 23 may also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The end cap 23 can also be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiment of the present application.

The casing 21 is a component used to cooperate with the end cover 23 to form an internal environment of the battery cell 20 , wherein the formed internal environment can be used to accommodate the electrode assembly 24 , the insulating glue 26 , the electrolyte and other components. The housing 21 and the end cover 23 may be independent components, and an opening may be provided on the housing 21. The end cover 23 covers the opening at the opening to form the internal environment of the battery cell 20. Without limitation, the end cover 23 and the housing 21 can also be integrated. Specifically, the end cover 23 and the housing 21 can form a common connection surface before other components are put into the housing. When it is necessary to encapsulate the inside of the housing 21 When the end cap 23 is closed, the housing 21 is closed. The housing 21 can be of various shapes and sizes, such as rectangular parallelepiped, cylinder, hexagonal prism, etc. Specifically, the shape of the housing 21 can be determined according to the specific shape and size of the electrode assembly 24 . The housing 21 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiments of the present application.

Referring also to FIG. 7 , the electrode assembly 24 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 24 may be contained within the housing 21 . The electrode assembly 24 is mainly formed by winding or stacking positive electrode sheets and negative electrode sheets, and a separator is usually provided between the positive electrode sheets and the negative electrode sheets. The electrode assembly 24 includes a main body 241 and a tab 242 protruding from the main body 241. The tab 242 has an adhesive surface 2423. The adhesive surface 2423 has a root area 24231, a connection area 24232 and a soldering area 24233. The root area 24231 and The main body part 241 is connected, and the connection area 24232 is connected between the root area 24231 and the soldering area 24233.

Among them, the separator, the part of the positive electrode sheet with active material, and the part of the negative electrode sheet with active material are jointly constructed to form the main body 241 of the electrode assembly 24 , the part of the positive electrode sheet that does not have active material is constructed to form the positive electrode tab, and the negative electrode sheet does not have Partial structures of the active material form negative electrode tabs. All the positive electrode sheets are stacked along the stacking direction of the positive electrode sheets and the negative electrode sheets to form the positive electrode tabs 2421, and all the negative electrode sheets are stacked along the stacking direction of the positive electrode sheets and the negative electrode sheets to form the negative electrode tabs 2422. During the charging and discharging process of the battery 100, the positive active material and the negative active material react with the electrolyte, and the tabs 242 are connected to the poles 22 to form a current loop.

The pole tab 242 is protruding from one end of the main body portion 241 and extends along its protruding direction. The pole tab 242 has a root portion, a connecting portion and a soldering portion sequentially arranged along its extending direction. The root part is connected to the main part 241, and the connection part is connected between the root part and the soldering mark part. The soldering mark part is provided with a soldering mark 24235, and the soldering mark 24235 extends along the width direction of the soldering mark area 24233 to two opposite boundary lines of the soldering mark area 24233. . The welding mark 24235 is mainly used to mark the welding position between the tab 242 and the adapter 25 or the pole post 22 . The surface of the root facing the insulating glue 26 forms a root area 24231, the surface of the connecting portion facing the insulating glue 26 forms a connecting area 24232, and the surface of the soldering portion facing the insulating glue 26 forms a soldering area 24233.

Since the root part is the connection part between the tab 242 and the main body part 241, the stress is relatively concentrated and it is easy to be torn due to force. Since the connecting part is adjacent to the welding part, its mechanical strength is relatively weak and it is easy to tear due to force.

The electrode assembly 24 has two tabs 242 , one of which is a positive tab 2421 and the other tab 242 is a negative tab 2422 . The end cap 23 has two poles 22 , one of which is a positive pole 221 and the other pole 22 is a negative pole 222 . The positive electrode ear 2421 can be connected to the positive electrode post 221 directly or through the adapter 25, and the negative electrode ear 2422 can be connected to the negative electrode post 222 directly or through the adapter 25 to form a current loop.

Please refer to FIG. 6 again. The insulating glue 26 has a glue-coated surface 261 . The glue-coated surface 261 has a first glue-coated area 2611 , a non-glued area 2612 and a second glue-coated area 2613 that are continuously arranged along the width direction of the insulating glue 26 . Among them, the first glued area 2611 is bonded to the main body part 241, the non-glued area 2612 covers at least one of the root area 24231 and the connection area 24232, and the second glued area 2613 is bonded to the soldering area 24233.

The number of insulating glue 26 is equal to the sum of the numbers of positive electrode tabs 2421 and negative electrode tabs 2422. Taking the electrode assembly 24 as one and including one positive electrode tab 2421 and one negative electrode tab 2422 as an example, there are two pieces of insulating glue 26, one of which is the insulating glue. 26 is a positive electrode insulating glue and is used to bond the positive electrode lug 2421 and the main body part 241. The other insulating glue 26 is a negative electrode insulating glue and is used to bond the negative electrode lug 2422 and the main body part 241. For example, there are two electrode assemblies 24 , each including a positive electrode tab 2421 and a negative electrode tab 2422 . There are four insulating glues 26 , including two positive electrode insulating glues and two negative electrode insulating glues.

It is worth mentioning that the positive electrode insulating glue has the same structure as the negative electrode insulating glue, the structure of the positive electrode lug 2421 is exactly the same as the structure of the negative electrode lug 2422, and the connection relationship between the positive electrode insulating glue, the positive electrode lug 2421 and the main body 241, and The connection methods between the negative electrode insulating glue, the negative electrode tab 2422 and the main body 241 are exactly the same. In the following embodiments, the pole tab 242 is the positive pole tab 2421 and the insulating glue 26 is the positive insulating glue.

In one embodiment, the insulating glue 26 includes a base material and an adhesive layer. The base material can be made of polyethylene terephthalate plastic (PET), polypropylene (PP) or other materials, and the adhesive layer can be made of pressure-sensitive adhesive. layer, UV adhesive layer and other materials. The base material has a bearing surface for bearing the adhesive layer, and the adhesive layer is coated on the bearing surface and has an adhesive effect.

In some embodiments, the glue layer includes a first glue layer and a second glue layer. The first glue layer and the second glue layer are spaced apart along the width direction of the substrate. The surface of the first glue layer facing away from the substrate forms a first coating. The glue area 2611 and the area not covered with the glue layer on the bearing surface form a non-glue area 2612. The surface of the second glue layer facing away from the base material forms a second glue area 2613. The first glue area 2611 and the second glue area 2613 flush.

In some embodiments, the thickness of the substrate is K1, and K1 satisfies the condition 0.02 millimeters (mm) ≤ K1 ≤ 0.03mm.

In some embodiments, K2 of the first glue layer satisfies the condition 0.02mm≤K2≤0.03mm.

In some embodiments, K3 of the second glue layer, K3 satisfies the condition 0.02mm≤K2≤0.03mm.

Taking the number of electrode assemblies 24 as two and the electrode assembly 24 and the pole 22 as an example, the actual manufacturing process is as follows: first, the main body parts 241 of the two electrode assemblies 24 are spaced on the opposite sides of the end cover 23, and each electrode The side of the pole lug 242 of the component 24 facing away from the bonding surface 2423 overlaps with the corresponding pole post 22 . Then, the laser welder is disposed toward the bonding surface 2423 and emits laser light to the welding marks 24235 of each electrode assembly 24 in order to weld the tabs 242 and the pole posts 22 . Afterwards, the main body 241 and tabs 242 of each electrode assembly 24 are fixed using insulating glue 26 . After that, the root part of each electrode assembly 24 is bent relative to the connecting part, so that the main body parts 241 of the two electrode assemblies 24 can be arranged side by side on the inside of the end cover 23 along the thickness direction X of the electrode assembly 24. Finally, the two electrode assemblies 24 are connected. Each electrode assembly 24 is assembled into the housing 21 , and the end cover 23 covers the opening of the housing 21 , and the battery cell 20 can be assembled.

The non-glued area 2612 covers at least one of the root area 24231 and the connection area 24232, including multiple embodiments. For example, in one embodiment, the non-glued area 2612 covers the root area 24231, and the second glue-coated area 2613 covers the connection area 24232. In this embodiment, during vibration and impact, the root with the root area 24231 is not easily pulled and torn by the insulating glue 26 . For another example, in one embodiment, the first glued area 2611 covers the root area 24231, and the non-glued area 2612 covers the connection area 24232. In this embodiment, during vibration and shock, the connecting portion with the connecting area 24232 is not easily pulled and torn by the insulating glue 26 . For another example, in one embodiment, the non-glued area 2612 covers the root area 24231 and the connection area 24232. In this embodiment, during vibration and impact, the root portion with the root area 24231 and the connection portion with the connection area 24232 are not easily pulled and torn by the insulating glue 26 .

In this application, the first glued area 2611 is bonded to the main body 241, the second glued area 2613 is bonded to the welding area 24233, and the non-glued area 2612 covers the root area 24231 and the connection area 24232. At least one of them, since the first glue-coated area 2611, the non-glued area 2612 and the second glue-coated area 2613 are continuously arranged, the insulating glue 26 can completely cover the tab 242, and can fix and support each tab piece. This prevents the pole tabs from bending due to force and overlapping with the main body 241 , thereby reducing the risk of short circuit inside the electrode assembly 24 .

Moreover, since the second glued area 2613 is bonded to the solder print area 24233, the insulating glue 26 can block the solder slag at and around the solder print 24235, thereby weakening the solder slag sputtering and overlapping the tab. 242 and the main body 241. Even if the welding slag leaks, since the insulating glue 26 completely covers the tab 242 and has an insulating effect, it can prevent the welding slag from overlapping between the tab 242 and the main body 241 , thus further reducing the internal short circuit of the electrode assembly 24 risks of.

In addition, the non-glued area 2612 covers at least one of the root area 24231 and the connecting area 24232, so that when there is a vibration impact, the root of the root area 24231 is covered by the non-glued area 2612, and/or has the root area covered by the non-glued area 2612. The connection portion of the connection area 24232 covered by the glue coating area 2612 is no longer pulled by the insulating glue 26, thereby preventing the root area 24231 and/or the connection area 24232 from cracking. In this way, the safety of the battery cell 20 is also improved.

In some embodiments of the present application, the non-glued area 2612 covers the root area 24231 and the connection area 24232.

In this way, the root portion with the root area 24231 and the connection portion with the connection area 24232 are not easily pulled and torn by the insulating glue 26, thus ensuring better safety of the battery cell 20, the battery 100 and the electrical device.

Please refer to Figure 4 and Figure 7 again. In some embodiments of the present application, the bonding surface 2423 also includes a head area 24234. The head area 24234 is arranged on the side of the soldering area 24233 away from the connection area 24232; the second coating The glue area 2613 is bonded to the head area 24234.

The pole tab 242 also has a head. In the extension direction of the pole tab 242, the head is located downstream of the soldering mark and connected to the soldering mark. The surface of the head facing the insulating glue 26 forms a head area 24234.

By providing the head region 24234, a larger bonding area is provided between the insulating glue 26 and the tab 242, thereby improving the reliability of the bonding between the tab 242 and the main body portion 241. Furthermore, the insulating glue 26 can support the tabs 242 more reliably to prevent the tabs 242 from overlapping with the main body 241 , so that the battery 100 has greater safety.

In some embodiments of the present application, the main body 241 includes a first surface 2411 with protruding tabs 242 and a second surface 2412 located in the thickness direction X of the electrode assembly 24. The second surface 2412 and the bonding surface 2423 Located on the same side of the electrode assembly 24; the first glue coating area 2611 is bonded to the first surface 2411 and the second surface 2412.

Wherein, the second surface 2412 is arranged adjacent to the first surface 2411.

The first glue coating area 2611 is bonded to the first surface 2411 and the second surface 2412. Compared with the first glue coating area 2611 being directly bonded to the first surface 2411, the first glue coating area 2611 is bonded to the main body 241. The larger the connecting area, the better the bonding reliability, and the wider the insulation coverage. In this way, the possibility of overlapping the tab 242 and the main body 241 directly or indirectly through welding slag is also better, so the battery cell 20 , the safety of the battery 100 and the electrical device is also higher.

Please refer to Figure 5, Figure 6 and Figure 8 again. In some embodiments of the present application, the width of the first glue coating area 2611 is W1, and the width of the first glue coating area 2611 and the second surface 2412 is L1. 2mm≤W1-L1.

That is to say, after the first glue coating area 2611 is bonded to the second surface 2412, there must be a remaining portion that can be bonded to the first surface 2411, and the remaining portion can ensure that the first glue coating area 2611 can be bonded to the first surface 2412. Second surface 2412 performs bonding. Due to manufacturing errors of the insulating glue 26 or operating errors of the operator, a portion of the first glue coating area 2611 can be allowed to be bonded to the root area 24231, and the width of this portion is within the allowable range of the error.

It can be seen that by setting the width of the first glue coating area 2611 and the second surface 2412 to be L1, 2mm≤W1-L1, the bonding firmness and insulation reliability of the insulating glue 26 can be effectively improved, thereby ensuring The battery cell 20 has better safety.

In some embodiments of the present application, the width of the non-glued area 2612 is W2, the width of the first glued area 2611 and the first surface 2411 is L2, the width of the root area 24231 is L3, and the width of the connecting area 24232 For L4, 0mm＜W1+W2-L1-L2-L3-L4≤2mm.

If W1=L1+L2 is set exactly, and W2=L3+L4 is set, due to the glue application error, the widths of W1 and W2 in the formed insulating glue 26 may be small, causing W1 to be unable to adhere firmly to the main body 241, and W2 It also cannot completely cover the root area 24231 and the connection area 24232, resulting in an insignificant improvement in the safety of the battery cell 20 .

By setting 0mm＜W1+W2-L1-L2-L3-L4≤2mm, it is possible to ensure that the width of the insulating glue 26 is relatively large, and it can be firmly bonded to the main body 241 and has sufficient size. The root area 24231 and the connection area 24232 can be completely covered, thereby helping to better support the tab 242 and enhancing the insulation effect between the tab 242 and the main body 241 .

In some embodiments of the present application, there are two electrode assemblies 24 and they are arranged side by side along the thickness direction W1+W2+W3<L1+L2+L3+L4+L5.

There is a dividing line between the connection area 24232 and the soldering area 24233 on each tab 242. The distance L5 between the boundary lines where the soldering areas 24233 in the two electrode assemblies 24 are far away from each other refers to: one of the The dividing line between the connecting area 24232 and the soldering area 24233 on the positive electrode lug 2421 in the electrode assembly 24, and the dividing line between the connecting area 24232 and the soldering area 24233 on the positive electrode lug 2421 in the other electrode assembly 24 Pitch. The distance L5 between the boundary lines where the soldering areas 24233 in the two electrode assemblies 24 are far away from each other also refers to: the dividing line between the connecting area 24232 and the soldering area 24233 on the negative electrode lug 2422 in one of the electrode assemblies 24, and The distance between the dividing line between the connecting area 24232 and the soldering area 24233 on the negative electrode lug 2422 in the other electrode assembly 24 .

By setting W1+W2+W3<L1+L2+L3+L4+L5, the insulating glue 26 bonded to the positive electrode lug 2421 in one of the electrode assemblies 24 can be prevented from extending to the positive electrode in the other electrode assembly 24. The connecting area 24232 of the ear 2421 and being bonded to the connecting area 24232 can also prevent the insulating glue 26 bonded to the negative electrode ear 2422 in one of the electrode assemblies 24 from extending to the connection with the negative electrode ear 2422 in the other electrode assembly 24 area 24232 and bonded with the connection area 24232, thereby ensuring that the non-glued area 2612 covers the connection area 24232 to prevent the tab 242 from being torn by the insulating glue 26, which helps to improve the battery 100 and battery cells. Body 20 security.

In one embodiment, the root area 24231 and the connection area 24232 are arranged at an angle. The angle between the root area 24231 and the connection area 24232 is A, and A satisfies the condition: A<90°.

After the electrode assembly 24 and the end cap 23 are welded, by bending the root portion relative to the connection portion, the root area 24231 can be driven to rotate toward the connection area 24232 around its boundary line with the connection area 24232, so that the two electrode assemblies 24 can The main body portion 241 can be arranged side by side inside the end cap 23 along the thickness direction X of the electrode assembly 24 .

By setting A, the condition is satisfied: A<90°. Therefore, the operation root can be easily rotated relative to the connecting portion, which helps to improve the ease of assembly of the battery cell 20 .

In some embodiments of the present application, the battery cell 20 further includes an adapter 25 . The adapter 25 is provided on the side of the tab 242 facing away from the bonding surface 2423 and is connected to the area opposite the soldering area 24233 .

Please refer to FIG. 4 again and refer to FIG. 8 at the same time. The adapter 25 is a conductive component that realizes the electrical connection between the tab 242 and the pole 22 . The adapter 25 is disposed in the housing 21 and is located on the side of the tab 242 facing away from the bonding surface 2423 and connected to the area opposite the soldering area 24233. The adapter 25 is located between the side of the pole tab 242 facing away from the bonding surface 2423 and the inside of the end cover 23 , and is welded to the pole tab 242 and the pole post 22 on the end cover 23 .

There are two adapters 25 , one of which is a positive adapter 251 and is used to electrically connect the positive pole 221 and the positive ears 2421 in all electrode assemblies 24 , and the other is a negative adapter 252 and is used to The negative electrode post 222 is electrically connected to the negative electrode tabs 2422 in all electrode assemblies 24 . The adapter 25 can be made of copper, aluminum or other metal materials with better mechanical properties. It is worth mentioning that the structure of the positive adapter 251 and the negative adapter 252 are exactly the same. The connection relationship between the positive adapter 251 and the positive lug 2421 and the main body 241 is the same as that of the negative adapter 252 and the negative lug 2422. The connection relationship between the main body part 241 and the main body part 241 is exactly the same. The following embodiments are all described by taking the adapter 25 as the positive adapter 251 as an example.

In some embodiments, an insulating member may also be provided inside the end cover 23 , and the insulating member may be used to isolate the adapter 25 and the end cover 23 in the housing 21 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, etc.

Take for example that there are two electrode assemblies 24 and the electrode assemblies 24 and the adapter 25 are welded: first, the main body parts 241 of the two electrode assemblies 24 are spaced on the opposite sides of the end cover 23, and The side of the pole lug 242 facing away from the bonding surface 2423 overlaps with the corresponding adapter 25 . Then, the laser welder is positioned toward the bonding surface 2423 and emits laser light to the welding marks 24235 of each electrode assembly 24 in order to weld the tabs 242 and the adapter 25 . Then, insulating glue 26 is used to fix the main body 241 , tabs 242 and adapter 25 in each electrode assembly 24 . Next, the adapter 25 is welded to the pole 22 of the end cap 23 so that the two electrode assemblies 24, the adapter 25 and the end cap can form an integral body. After that, the root part of each electrode assembly 24 is bent relative to the connecting part, so that the main body parts 241 of the two electrode assemblies 24 can be arranged side by side on the inside of the end cover 23 along the thickness direction X of the electrode assembly 24. Finally, the two electrode assemblies 24 are connected. Each electrode assembly 24 is assembled into the housing 21 , and the end cover 23 covers the opening of the housing 21 , and the battery cell 20 can be assembled.

By providing the adapter 25, the electrical connection between the tab 242 and the pole post 22 can be facilitated.

In a second aspect, the present application provides a battery 100, which includes the battery cell 20 as described in any one of the above.

In a third aspect, the present application provides an electrical device, which includes the battery 100 as described in the above embodiments. The battery 100 is used to provide electric energy, or includes the battery cell 20 as described in any of the above embodiments. The battery cells 20 are used to provide electrical energy.

According to some embodiments of the present application, the present application provides a battery cell 20. The battery cell 20 includes an electrode assembly 24 and an insulating glue 26. The electrode assembly 24 includes a main body part 241 and tabs 242 protruding from the main body part 241. , the tab 242 has an adhesive surface 2423, the adhesive surface 2423 has a root area 24231, a connection area 24232 and a soldering area 24233, the root area 24231 is connected to the main body 241, the connection area 24232 is connected to the root area 24231 and the soldering area 24233 In between, the insulating glue 26 has a glue-coated surface 261 , and the glue-coated surface 261 has a first glue-coated area 2611 , a non-glued area 2612 and a second glue-coated area 2613 that are continuously arranged along the width direction of the insulating glue 26 . Among them, the first glued area 2611 is bonded to the main body part 241, the non-glued area 2612 covers the root area 24231 and the connection area 24232, and the second glued area 2613 is bonded to the soldering area 24233. In such a battery cell 20, the root portion with the root area 24231 and the connection portion with the connection area 24232 are not easily torn by the insulating glue 26, so the battery cell 20, the battery 100 and the electrical device can be protected. Has better security.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application. The scope shall be covered by the claims and description of this application. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any way. The application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A battery cell, characterized in that the battery cell includes:

The electrode assembly includes a main body and tabs protruding from the main body. The tabs have an adhesive surface. The adhesive surface has a root area, a connection area and a soldering area. The root area is connected to the main body, and the connection area is connected to the root area. and between the solder print area; and

Insulating glue has a glue-coated surface, and the glue-coated surface has a first glue-coated area, a non-glued area and a second glue-coated area continuously arranged along the width direction of the insulating glue;

The first glued area is bonded to the main body, the non-glued area covers at least one of the root area and the connection area, and the second glued area is bonded to the soldering area.
The battery cell according to claim 1, wherein the non-glued area covers the root area and the connection area.
The battery cell according to any one of claims 1 to 2, characterized in that the bonding surface further includes a head area, and the head area is arranged on the side of the soldering area away from the connection area;

The second glued area is bonded to the head area.
The battery cell according to any one of claims 1 to 3, wherein the main body portion includes a first surface on which the tabs are protruded, and a second surface located in the thickness direction of the electrode assembly, and the second surface and The bonding surface is located on the same side of the electrode assembly;

The first glue coating area is bonded to the first surface and the second surface.
The battery cell according to claim 4, wherein the width of the first glue-coated area is W1, and the width of the first glue-coated area and the second surface is L1, and 2mm≤W1-L1.
The battery cell according to claim 5, wherein the width of the non-glued area is W2, the width of the first glue-coated area and the first surface is L2, the width of the root area is L3, and the width of the connecting area is L2. The width is L4, 0mm＜W1+W2-L1-L2-L3-L4≤2mm.
The battery cell according to claim 6, wherein there are two electrode assemblies and they are arranged side by side along the thickness direction of the electrode assemblies;

The distance between the boundary lines of the soldering areas in the two electrode assemblies that are far away from each other is L5, W1+W2+W3<L1+L2+L3+L4+L5.
The battery cell according to any one of claims 1 to 7, characterized in that the root area and the connection area are arranged at an angle, the angle between the root area and the connection area is A, and A satisfies the condition: A<90°.
The battery cell according to any one of claims 1 to 8, further comprising an adapter, which is disposed on the side of the tab facing away from the bonding surface and connected to the area opposite the soldering area. .
A battery, characterized by comprising the battery cell according to any one of the above claims 1 to 9.
An electrical device, characterized in that it includes a battery as claimed in claim 10, said battery being used to provide electrical energy, or a battery cell as described in any one of claims 1 to 9, said Battery cells are used to provide electrical energy.