Battery cell, battery, and electric device

Abstract

The application relates to a battery monomer, a battery and a power utilization device. The battery monomer comprises an electrode lead-out part, an electrode assembly, a tab, a first protective piece and a second protective piece. The tab comprises a connecting part and a bending part. The connecting part is welded with the electrode lead-out part to form a first welding area. The tab is bent at the bending part. The first protective piece comprises a first base material layer and a first adhesive layer. The first adhesive layer and the first base material layer form a first adhesive part. The first adhesive part at least adheres and covers part of the first welding area. The second protective piece comprises a second base material layer and a second adhesive layer. The second adhesive layer and the second base material layer form a second adhesive part. The second adhesive part at least adheres and covers part of the main body part. The first base material layer and the second base material layer have different thicknesses. The first base material layer and the second base material layer have an overlapping area. The first protective piece has a first non-adhesive part. The second protective piece has a second non-adhesive part. The battery monomer, the battery and the power utilization device provided by the application can reduce the risk of tab cracking and damage.

Description

Technical Field

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

[0002] Currently, during the manufacturing process of battery cells, after the tabs and electrode leads in the battery cell are welded, an insulating tape is applied to the weld mark to prevent weld slag from falling off later. Furthermore, to protect the tabs and prevent short circuits caused by inverted tab insertion, the insulating tape extends to the main body of the electrode assembly in the battery cell. However, this method of applying the tape may cause abnormal adhesion between the insulating tape and the tab, leading to the tape pulling on the tab during subsequent core assembly, causing the tab to crack. This reduces the tab's current carrying capacity and causes the battery to overheat. In addition, cracked tabs can easily tear the insulating tape, leading to short circuits and affecting the battery's lifespan.

[0003] In addition, the tab has a first welding area for welding to the electrode lead-out portion. A tab support is generally provided between the first welding area and the main body of the electrode assembly to support the tab, ensuring it is in the correct position. The tab support also provides insulation to prevent the tab from connecting to the main body and short-circuiting. However, during the assembly of the tab support, it can tear the insulating tape and the tab, and in severe cases, even damage the insulating tape and the tab, affecting the battery's electrical performance. Utility Model Content

[0004] Therefore, it is necessary to provide a battery cell, battery, and power device that can reduce the risk of tab cracking and damage in order to address the above problems.

[0005] In a first aspect, this application provides a battery cell, the battery cell comprising:

[0006] Electrode leads are used to extract electrical energy from the battery cells;

[0007] An electrode assembly includes a main body and an electrode tab. The electrode tab includes a connecting part, a bending part, and a root part. The connecting part is welded to the electrode lead-out part to form a first welding area. The root part is connected to the main body. The bending part is connected between the connecting part and the root part. The electrode tab is bent at the bending part.

[0008] A first protective member, at least partially located between the main body and the connecting portion, the first protective member comprising a first substrate layer and a first adhesive layer stacked thereon, the first adhesive layer forming a first adhesive portion with the first substrate layer, the first adhesive portion at least bonding to and covering a portion of the first welding area; and

[0009] The second protective member is at least partially located between the main body and the connecting portion. The second protective member includes a stacked second substrate layer and a second adhesive layer. The second adhesive layer and the second substrate layer form a second adhesive portion. The second adhesive portion at least bonds to and covers a portion of the main body.

[0010] The first substrate layer and the second substrate layer have different thicknesses, and along the extension direction of the tab, the first substrate layer and the second substrate layer have an overlapping area;

[0011] Wherein, the first substrate layer has a first non-adhesive portion extending beyond the first adhesive layer, and / or, the second substrate layer has a second non-adhesive portion extending beyond the second adhesive layer.

[0012] In some embodiments, the first non-adhesive portion includes the first substrate layer located in the overlapping area; and / or, the second non-adhesive portion includes the second substrate layer located in the overlapping area.

[0013] In some embodiments, the first substrate layer, which is at least partially located in the overlapping area, provides support for the bent portion, and / or the second substrate layer, which is at least partially located in the overlapping area, provides support for the bent portion.

[0014] In some embodiments, in the overlapping region, the first substrate layer is located between the bent portion and the second substrate layer;

[0015] The thickness of the first substrate layer is greater than the thickness of the second substrate layer, and the first substrate layer provides the supporting force; or, the thickness of the second substrate layer is greater than the thickness of the first substrate layer, and the second substrate layer provides the supporting force.

[0016] In some embodiments, in the overlapping area, the second substrate layer is located between the bent portion and the first substrate layer;

[0017] The thickness of the first substrate layer is greater than the thickness of the second substrate layer, and the first substrate layer provides the supporting force; or, the thickness of the second substrate layer is greater than the thickness of the first substrate layer, and the second substrate layer provides the supporting force.

[0018] In some embodiments, the thickness of the first substrate layer is h11, h11≥0.01mm, and / or the thickness of the second substrate layer is h21, 0.01mm≤h21≤0.1mm.

[0019] In some embodiments, 0.025mm ≤ h11 ≤ 0.1mm.

[0020] In some embodiments, the thickness of the first adhesive layer is h12, 0.025mm≤h12≤0.1mm, and / or the thickness of the second adhesive layer is h22, 0.005mm≤h22≤0.1mm.

[0021] In some embodiments, the first adhesive portion adheres to and covers at least a portion of the connection portion located between the first welding area and the bend.

[0022] In some embodiments, the second adhesive portion extends to the root portion, and the second adhesive portion adheres to and covers a portion of the root portion.

[0023] In some embodiments, along the extension direction of the tab, the length of the first substrate layer is a, the length of the first adhesive portion is b, and b ≥ a / 2.

[0024] In some embodiments, the first non-adhesive portion and the second non-adhesive portion overlap to form the overlapping area, the length of the overlap being e, c / 5≤e≤2c / 3, where c is the length of the tab, and / or e≥5mm.

[0025] In some embodiments, the bond strength between the first adhesive portion and the first welded area is P1, and the bond strength between the second adhesive portion and the main body is P2; P1 ≥ P2; and / or, 2N / 25mm ≤ P1 ≤ 15N / 25mm, and / or, 1N / 25mm ≤ P2 ≤ 7N / 25mm; and / or

[0026] The Rockwell hardness of the first protective component is K1, and the Rockwell hardness of the second protective component is K2, where K1 ≥ K2, and / or K1 ≥ 100, and / or K2 ≥ 80; and / or

[0027] The tensile strength of the first protective component is M1, and the tensile strength of the second protective component is M2, where M1 < M2, and / or M1 > 50 MPa, and / or M2 > 50 MPa.

[0028] In some embodiments, the electrode lead-out portion includes an adapter piece and an electrode post, the adapter piece and the electrode post are welded to form a second welding area, the second welding area and the first welding area are arranged along the width direction of the electrode tab, and the first adhesive portion is bonded to and covers at least a portion of the second welding area.

[0029] In some embodiments, the battery cell includes a first electrode assembly and a second electrode assembly stacked on top of each other; wherein...

[0030] The first protective element, which is integrally connected to the two tabs of the same polarity in the first electrode assembly and the second electrode assembly, is provided in one piece.

[0031] And / or, in the same electrode assembly, the two first protective members connected to the two tabs of opposite polarity are respectively disposed separately;

[0032] And / or, the two second protective members connected to the two tabs of opposite polarity in the same electrode assembly are separately disposed.

[0033] In some embodiments, the battery cell further includes a housing and an explosion-proof valve. The housing includes a casing and a top cover. The casing is used to accommodate the electrode assembly, the first protective member, and the second protective member. The top cover is used to cover the casing. The explosion-proof valve is disposed on the top cover. In the thickness direction of the top cover, the projection of the explosion-proof valve does not overlap with the projection of the first protective member.

[0034] Secondly, this application provides a battery comprising a battery cell as described in any of the above embodiments.

[0035] Thirdly, this application provides an electrical device that includes a battery as described in the above embodiments.

[0036] Compared with the prior art, this application has the following beneficial effects:

[0037] In the aforementioned battery cell, battery, and electrical device, the first adhesive portion at least bonds to and covers a portion of the first welding area to fix the weld slag formed by welding the tab and the electrode lead-out portion, reducing the risk of weld slag falling off. Furthermore, the first adhesive portion is at least partially bonded to the first welding area, and the second adhesive portion at least bonds to and covers a portion of the main body. Along the tab's extension direction, the first substrate layer and the second substrate layer have an overlapping area. In this way, the first protective component and the second protective component work together to cover the tab, thereby protecting it, preventing reverse insertion, and improving insulation.

[0038] Furthermore, separating the first and second protective components reduces the risk of them pulling on the tabs, separator, and electrodes, thus lowering the risk of tab cracking and separator / electrode damage. A lower risk of tab cracking increases the tab's current-carrying capacity, resulting in slower cell temperature rise. A lower risk of tab cracking also reduces the likelihood of the tab contacting the main body and short-circuiting, thereby extending the cell's lifespan. The reduced risk of separator / electrode damage further extends the cell's lifespan.

[0039] In addition, the first and second protective components are separately configured. In embodiments where a tab support needs to be assembled, the tab support can be installed between the surface of the main body where the tab is located and the first protective component. During the assembly of the tab support, the risk of the tab support causing tearing and damage to the first and second protective components and the tab is small, thus improving the electrical performance of the battery.

[0040] Furthermore, the first and second substrate layers have different thicknesses and overlap along the tab extension direction. This allows for adaptation to the thickness requirements of the first and second protective components at different locations, reducing the impact of the tab support. Even when the first and second substrate layers are relatively thick, they can replace the tab support to support the tab, further reducing the adverse effects of the tab support on electrical performance. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall structure of a single battery cell in one embodiment of this application;

[0042] Figure 2 for Figure 1 The exploded view of the battery cell after the second protective component has been removed;

[0043] Figure 3 for Figure 1 The exploded view of the battery cell after the first protective component has been removed;

[0044] Figure 4 A schematic diagram of a structure in which two electrode assemblies with a first-shaped electrode tab are stacked along the thickness direction of the electrode assembly and cooperate with an adapter piece, a first protective component, a second protective component and an electrode tab support component;

[0045] Figure 5 A schematic diagram of a structure in which two electrode assemblies with a second-shaped electrode tab are stacked along the thickness direction of the electrode assembly and cooperate with an adapter piece, a first protective component, a second protective component and an electrode tab support component;

[0046] Figure 6 A schematic diagram of a structure in which two electrode assemblies with a third-shaped electrode tab are stacked along the thickness direction of the electrode assembly and cooperate with an adapter piece, a first protective member and a second protective member;

[0047] Figure 7 A schematic diagram of a structure in which two electrode assemblies with a fourth type of electrode tab are stacked along the thickness direction of the electrode assembly and cooperate with an adapter piece, a first protective component, a second protective component and an electrode tab support component;

[0048] Figure 8This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the first embodiment, and after they are in conjunction with the adapter piece, the first protective member, the second protective member and the tab support member.

[0049] Figure 9 This is a cross-sectional view along the AA direction of the two electrode assemblies stacked along the thickness direction of the electrode assemblies in the second embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the electrode tab support member.

[0050] Figure 10 This is a cross-sectional view along the AA direction of the two electrode assemblies stacked along the thickness direction of the electrode assemblies in the third embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the electrode tab support member.

[0051] Figure 11 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the fourth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0052] Figure 12 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the fifth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0053] Figure 13 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the sixth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0054] Figure 14 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the seventh embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0055] Figure 15 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the eighth embodiment, and after they are in conjunction with the adapter piece, the first protective member, the second protective member and the tab support member.

[0056] Figure 16 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the ninth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0057] Figure 17This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the tenth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0058] Figure 18 This is a cross-sectional view along the AA direction of the two electrode assemblies stacked along the thickness direction of the electrode assemblies in the eleventh embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the electrode tab support member.

[0059] Figure 19 This is a top view of the first protective element in one embodiment;

[0060] Figure 20 for Figure 19 The side view of the first protective component shown;

[0061] Figure 21 This is a schematic diagram of the structure of the second protective component in one embodiment;

[0062] Figure 22 for Figure 21 Top view of the second protective component shown;

[0063] Figure 23 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the twelfth embodiment, and after they are in conjunction with the adapter piece, the first protective member and the second protective member.

[0064] Figure 24 This is a cross-sectional view along the AA direction of the thirteenth embodiment, showing two electrode assemblies stacked along the thickness direction of the electrode assemblies and in cooperation with the adapter piece, the first protective component, the second protective component and the tab support component.

[0065] Figure 25 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the fourteenth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0066] Figure 26 A side view of the first protective member in another embodiment;

[0067] Figure 27 This is a schematic diagram of the structure of the two electrode assemblies unfolded before being joined together in the fifteenth embodiment, and in cooperation with the adapter piece, the first protective component, and the second protective component;

[0068] Figure 28 This is a cross-sectional view along the AA direction of two electrode assemblies stacked along the thickness direction of the electrode assemblies in the sixteenth embodiment, and after they are in cooperation with the adapter piece, the first protective member, the second protective member and the tab support member.

[0069] Figure 29 for Figure 28 The diagram shows the structure of the two electrode assemblies unfolded before being joined together, and their cooperation with the adapter plate, the first protective component, and the second protective component.

[0070] Figure 30 This is a schematic diagram of the structure of the two electrode assemblies unfolded before being joined together in the seventeenth embodiment, and in cooperation with the adapter piece, the first protective component, and the second protective component;

[0071] Figure 31 This is a schematic diagram of the structure of the two electrode assemblies unfolded before being joined together in the eighteenth embodiment, and in cooperation with the adapter piece, the first protective component, and the second protective component;

[0072] Figure 32 This is a schematic diagram of the structure of the two electrode assemblies unfolded before being joined together in the nineteenth embodiment, and in cooperation with the adapter piece, the first protective component, and the second protective component;

[0073] Figure 33 This is a schematic diagram of the structure of the two electrode assemblies unfolded before being joined together in the twentieth embodiment, and in cooperation with the adapter piece, the first protective component, and the second protective component;

[0074] Figure 34 This is a schematic diagram of the structure of the two electrode assemblies unfolded before being joined together in the twenty-first embodiment, and in cooperation with the adapter piece, the first protective component, and the second protective component;

[0075] Figure 35 This is a front view of the two electrode assemblies unfolded before being joined together in the nineteenth embodiment, and in cooperation with the adapter piece, the first protective piece, and the second protective piece;

[0076] Figure 36 This is an exploded view of a battery in one embodiment of this application;

[0077] Figure 37 This is a schematic diagram of the structure of an electrical device in one embodiment of this application.

[0078] Icon labels:

[0079] 10000, Electrical appliances;

[0080] 1000, battery;

[0081] 100. Battery cell; 200. Outer casing;

[0082] 10. Electrode lead-out section; 20. Electrode assembly; 30. First protective component; 40. Second protective component; 50. Housing; 60. Explosion-proof valve; 70. Electrode tab support component;

[0083] 11. Adapter piece; 11a. Positive adapter piece; 11b. Negative adapter piece; 12. Terminal; 12a. Positive terminal; 12b. Negative terminal;

[0084] 20a, First electrode assembly; 20b, Second electrode assembly; 21, Main body; 22, Electrode tab; 22a, Positive electrode tab; 22b, Negative electrode tab; 221, Connecting part; 2211, First welding area; 2212, Second welding area; 222, Bending part; 223, Root part;

[0085] 31. First adhesive portion; 32. First non-adhesive portion; 33. First substrate layer; 34. First adhesive layer;

[0086] 41. Second adhesive portion; 42. Second non-adhesive portion; 43. Second substrate layer; 44. Second adhesive layer;

[0087] 51. Shell; 52. Top cover;

[0088] 210. Part One; 220. Part Two;

[0089] M, overlap region; Y, thickness direction of electrode assembly; Z, width direction of electrode assembly. Detailed Implementation

[0090] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0091] 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", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are 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.

[0092] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0093] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0094] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0095] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0096] Please see Figures 1 to 13 ,as well as Figure 23To alleviate the problem of electrode tab tearing, the applicant, after in-depth research, designed a battery cell 100, which includes a shell 50, an electrode lead-out portion 10, an electrode assembly 20, a first protective element 30, and a second protective element 40. The electrode assembly 20, the first protective element 30, and the second protective element 40 are all disposed within the shell 50. The electrode lead-out portion 10 is connected to the electrode tab 22 and is at least partially located outside the shell 51. The electrode lead-out portion 10 is used to draw out the electrical energy of the battery cell 100. The electrode assembly 20 includes a main body portion 21 and an electrode tab 22. The electrode tab 22 includes a connecting portion 221, a bending portion 222, and a root portion 223. The connecting portion 221 is welded to the electrode lead-out portion 10 to form a first welding area 2211. The root portion 223 is connected to the main body portion 21. The bending portion 222 is connected between the connecting portion 221 and the root portion 223. The electrode tab 22 bends at the bending portion 222. The first protective member 30 is at least partially located between the main body 21 and the connecting portion 221. The first protective member 30 includes a stacked first substrate layer 33 and a first adhesive layer 34. The first adhesive layer 34 and the first substrate layer 33 form a first adhesive portion 31, which at least bonds to and covers a portion of the first welding area 2211. The second protective member 40 is at least partially located between the main body 21 and the connecting portion 221. The second protective member 40 includes a stacked second substrate layer 43 and a second adhesive layer 44. The second adhesive layer 44 and the second substrate layer 43 form a second adhesive portion 41, which at least bonds to and covers a portion of the main body 21. The first substrate layer 33 and the second substrate layer 43 have different thicknesses, which are different along the extension direction of the tab 22 (e.g., ...). Figure 23 (As indicated by the zigzag arrow N), the first substrate layer 33 and the second substrate layer 43 have an overlapping area M; wherein, the first substrate layer 33 has a first non-adhesive portion 32 extending beyond the first adhesive layer 34, and / or, the second substrate layer 43 has a second non-adhesive portion 42 extending beyond the second adhesive layer 44. Furthermore, to improve the support effect of the tab 22, a tab support member 70 can be installed between the surface of the main body 21 where the tab 22 is located and the connecting portion 221 to support the tab 22.

[0097] like Figures 1 to 3 As shown, specifically, the outer casing 50 includes a housing 51 and a top cover 52. The top cover 52 cooperates with the housing 51 to form a sealed environment with a receiving cavity. The formed receiving cavity can be used to accommodate the electrode assembly 20, the first protective element 30, the second protective element 40, the electrolyte, and other components. The top cover 52 is used to house the electrode lead-out portion 10, the explosion-proof valve 60, and other components. The housing 51 and the top cover 52 can be independent components. An opening can be provided on the housing 51, and the top cover 52 can close the opening to form a closed environment. Alternatively, the top cover 52 and the housing 51 can be integrated.

[0098] like Figures 2 to 3As shown, the electrode assembly 20 is the main component in the battery cell 100 where electrochemical reactions occur. Typically, the electrode assembly 20 includes a positive electrode, a negative electrode, and a separator. The separator is disposed between the positive and negative electrode, insulating and isolating them while allowing ions to pass through. The portion of the positive electrode containing positive active material, the portion of the negative electrode containing negative active material, and the separator together form the main body 21 of the electrode assembly 20. The portion of the positive electrode without active material forms a positive electrode tab, and the portion of the negative electrode without active material forms a negative electrode tab. Multiple positive electrode tabs are stacked along the stacking direction of the positive and negative electrode (generally, this direction is the thickness direction Y of the electrode assembly 20) to form positive electrode tabs 22a, and multiple negative electrode tabs are stacked along the stacking direction of the positive and negative electrode to form negative electrode tabs 22b. During the charging and discharging process of the battery cell 100, the positive and negative active materials react with the electrolyte.

[0099] Please see Figures 4 to 7 The tab 22 protrudes from one end of the main body 21 along the width direction Z of the electrode assembly 20. The tab 22 has a connecting portion 221, a bent portion 222, and a root portion 223. The root portion 223 is connected to the main body 21. The bent portion 222 connects the root portion 223 and the connecting portion 221. The bent portion 222 is bent relative to the connecting portion 221 and connects between the connecting portion 221 and the root portion 223. The connecting portion 221 is typically welded for electrical connection to the electrode lead-out portion 10. The surface of the connecting portion 221 is parallel or approximately parallel to the thickness direction Y of the electrode assembly 20. The shape of the tab 22 in the final product may vary depending on its designed length and whether it is shaped. Figure 4 and Figure 7 The shape of the tab 22, which has a relatively large design redundancy and is formed after tab shaping, shows obvious crease lines between the connecting part 221 and the bent part 222, and between the bent part 222 and the root 223. It should be noted that the connecting part 221 shown in the figure extends straight, and the bent part 222 basically abuts against the tab support 70. In fact, this is just one possible form. Alternatively, the portion of the connecting part 221 extending beyond the first protective member 30 is slightly inclined downwards, and there is a certain distance between the bent part 222 and the tab support 70. Specifically, the tab pieces of the bent part 222 are tightly fitted together, and the thickness of the bent part 222 in the thickness direction Y of the electrode assembly 20 is the same as the thickness of the connecting part 221 (not shown; the thickness of the connecting part 221 refers to its dimension in the width direction Z of the electrode assembly 20). By giving the tab 22 a certain redundancy, the battery cell 100 can have greater free deformation space during manufacturing and assembly, making it less prone to tearing due to pulling. Figure 5As shown, the tab 22 here may also be unshaped and slightly tensioned by the tension provided by the first protective member 30 and the second protective member 40. There are no obvious crease lines between the connecting part 221 and the bent part 222, and between the bent part 222 and the root part 223. The shape shown in the figure is relatively regular. In fact, it may also have various shapes such as a flat arc shape. Figure 6 As shown in the figure, the electrode tab 22 has a small design redundancy, and the connecting part 22 is more concentrated in the middle, which can reduce the risk of the electrode tab 22 contacting the side wall of the housing 51.

[0100] Please see Figures 1 to 3 The electrode lead-out portion 10 is a component electrically connected to the tab 22 and capable of drawing electrical energy from the battery cell 100. As an example, the electrode lead-out portion 10 includes an adapter piece 11 and a terminal post 12, with the adapter piece 11 electrically connected between the tab 22 and the terminal post 12. Alternatively, the electrode lead-out portion 10 includes a terminal post 12, which is directly electrically connected to the tab 22. The adapter piece 11 is located within the receiving cavity of the housing 50, and the terminal post 12 is disposed on the top cover 52 and at least partially exposed. For ease of explanation, the following embodiments will be described using the electrode lead-out portion 10 including the adapter piece 11 and the terminal post 12 as an example.

[0101] Generally, the tab 22 includes a positive tab 22a and a negative tab 22b, the adapter 11 includes a positive adapter 11a and a negative adapter 11b, and the terminal 12 includes a positive terminal 12a and a negative terminal 12b. The positive adapter 11a is electrically connected between the positive tab 22a and the positive terminal 12a, and the negative adapter 11b is electrically connected between the negative tab 22b and the negative terminal 12b to form a current loop.

[0102] It is worth mentioning that the positive electrode tab 22a and the negative electrode tab 22b can have the same or different structures, and the positive electrode adapter 11a and the negative electrode adapter 11b can have the same or different structures. The specific structure can be set according to the requirements.

[0103] The first protective element 30 and the second protective element 40 may be, but are not limited to, insulating tape, and may be formed by bonding materials such as insulating resin, polypropylene, and polyethylene. The structures of the first protective element 30 and the second protective element 40 may be the same or different. The first protective element 30 and the second protective element 40 may be provided on the positive electrode tab 22a and / or the negative electrode tab 22b. The first protective element 30 and the second protective element 40 provided on the positive electrode tab 22a are used to protect the positive electrode tab 22a, and the first protective element 30 and the second protective element 40 provided on the negative electrode tab 22b are used to protect the negative electrode tab 22b.

[0104] Please see Figures 8 to 11 ,as well as Figure 13The first protective element 30 includes a first substrate layer 33 and a first adhesive layer 34 stacked together. The first adhesive layer 34 and the first substrate layer 33 form a first adhesive portion 31. The first adhesive portion 31 at least bonds to and covers a portion of the first welding area 2211.

[0105] Optionally, the first adhesive portion 31 bonds to and covers a portion of the first welding area 2211. Preferably, the first adhesive portion 31 bonds to and covers the entire first welding area 2211 to better fix the weld slag formed by welding the tab 22 and the electrode lead-out portion 10, reducing the risk of weld slag falling off. Optionally, the first adhesive portion 31 is entirely bonded to the first welding area 2211. Preferably, the first adhesive portion 31 is partially bonded to the first welding area 2211, and the remaining portion is bonded to the connecting portion 221, bending portion 222, etc., outside the first welding area 2211 (e.g., ...). Figure 13 As shown), this increases the bonding area of ​​the first adhesive part 31 and reduces the risk of the first protective member 30 falling off.

[0106] The second protective member 40 is located at least partially between the main body 21 and the connecting part 221. The second protective member 40 includes a second substrate layer 43 and a second adhesive layer 44 stacked together. The second adhesive layer 44 and the second substrate layer 43 form a second adhesive part 41. The second adhesive part 41 at least bonds to and covers a portion of the main body 21.

[0107] Optionally, the second adhesive portion 41 is entirely bonded to the main body portion 21 (specifically as follows). Figure 11 (As shown). Preferably, the second adhesive portion 41 is partially bonded to the main body portion 21, and the remaining portion is bonded to the electrode tab 22 (specifically as shown). Figures 8 to 10 As shown), this increases the bonding area of ​​the second protective member 40, prevents the second protective member 40 from falling off, and also protects the root 223 of the tab 22, reducing the risk of the tab 22 breaking at the root 223.

[0108] In this application, the first adhesive portion 31 at least bonds to and covers a portion of the first welding area 2211 to fix the weld slag formed by welding the tab 22 and the electrode lead-out portion 10, reducing the risk of weld slag falling off. Furthermore, the first adhesive portion 31 is at least partially bonded to the first welding area 2211, and the second adhesive portion 41 at least bonds to and covers a portion of the main body portion 21. Along the extension direction of the tab 22, the first substrate layer 33 and the second substrate layer 43 have an overlapping area M. Thus, the first protective member 30 and the second protective member 40 cooperate to jointly cover the tab 22, thereby protecting the tab 22, preventing it from being inserted backwards, and improving insulation. Moreover, by setting different thicknesses for the first substrate layer 30 and the second substrate layer 40, different substrate layers can play different roles or have different degrees of influence, but the combination achieves the effect of both supporting and protecting the tab 22 while reducing tension and the risk of tearing. Furthermore, the different thicknesses of the first substrate layer 33 and the second substrate layer 43 allow one to be thicker and thus replace the tab support 70, while the other remains thinner, preventing excessive tension on the whole and improving space utilization and cost. Therefore, this further reduces the adverse effects of the tab support 70 on electrical performance and brings other beneficial effects.

[0109] Furthermore, by separating the first protective component 30 and the second protective component 40, the risk of the first protective component 30 and the second protective component 40 pulling on the tab 22, separator, and electrode sheets can be reduced. This also reduces the risk of the tab 22 cracking and the separator and electrode sheets being damaged. A reduced risk of tab 22 cracking increases its current-carrying capacity, resulting in a slower temperature rise in the battery cell 100. A lower risk of tab 22 cracking also reduces the possibility of the tab 22 contacting the main body 21 and short-circuiting, thus extending the service life of the battery cell 100. The reduced risk of separator and electrode sheet damage further extends the service life of the battery cell 100. Furthermore, the first protective component 30 and the second protective component 40 are separately configured. In embodiments where the tab support component 70 needs to be assembled, the tab support component 70 can be installed between the surface of the main body 21 where the tab 22 is located and the first protective component 30. Although the tab support component 70 may press against the first protective component 30 or the second protective component 40 during manufacturing, assembly, etc., since the pressed end of the first protective component 30 or the second protective component 40 is not bonded and can deform freely, even if it is pressed, it will not exert a large pulling force on the tab 22, unlike adhesive tape that is fixed at both ends and pressed in the middle. Therefore, during the assembly of the tab support component 70, the risk of the tab support component 70 tearing or damaging the first protective component 30, the second protective component 40, and the tab 22 is small, thus improving the electrical performance of the battery 1000.

[0110] Please see Figure 4 , Figure 12 and Figure 13 In some embodiments, the first non-adhesive portion 32 includes a first substrate layer 33 located in the overlap region M; and / or, the second non-adhesive portion 42 includes a second substrate layer 43 located in the overlap region M. By designing the first non-adhesive portion 32 to include a first substrate layer 33 located in the overlap region M; and / or the second non-adhesive portion 42 to include a second substrate layer 43 located in the overlap region M, it can be ensured that the first protective member 30 and the second protective member 40 can be separately disposed and do not adhere to each other, thereby helping to reduce the possibility of the first protective member 30 and the second protective member 40 pulling on the tab 22 and the diaphragm.

[0111] Optionally, the overlapping area M is formed by the overlap of the first non-adhesive portion 32 and the second adhesive portion 41 (specifically as follows). Figure 12 (as shown), or, the overlapping area M is formed by the overlap of the first adhesive portion 31 and the second non-adhesive portion 42 (specifically as shown). Figure 13 (As shown).

[0112] Preferably, the overlapping area M is formed by the overlapping of the first non-adhesive portion 32 and the second non-adhesive portion 42 (e.g., Figure 4 , Figures 8 to 11 and Figure 23 (as shown), to prevent the first protective element 30 from sticking to the second protective element 40.

[0113] Please see Figure 4 , Figures 8 to 10 , Figure 14 and Figure 23 In some embodiments, a first substrate layer 33, at least partially located in the overlap region M, provides support for the bent portion 222, and / or a second substrate layer 43, at least partially located in the overlap region M, provides support for the bent portion 222.

[0114] When the first substrate layer 33, which is at least partially located in the overlap area M, provides support for the bent portion 222, the portion of the first substrate layer 33 located in the overlap area M may be disposed between the second substrate layer 43 and the bent portion 222, or the portion of the first substrate layer 33 located in the overlap area M may be disposed on the side of the second substrate layer 43 facing away from the bent portion 222.

[0115] When the second substrate layer 43, which is at least partially located in the overlap area M, provides support for the bent portion 222, the portion of the second substrate layer 43 located in the overlap area M may be disposed between the first substrate layer 33 and the bent portion 222, or the portion of the second substrate layer 43 located in the overlap area M may be disposed on the side of the first substrate layer 33 facing away from the bent portion 222.

[0116] In this embodiment, the bending portion 222 can be supported by the supporting force of the first substrate layer 33 and / or the second substrate layer 43, so as to reduce the risk of deformation of the bending portion 222, and more specifically, to reduce the risk of reverse insertion of the tab.

[0117] Preferably, both the first substrate layer 33 located in the overlapping area M and the second substrate layer 43 located in the overlapping area M provide support for the bent portion 222, thereby achieving a better support effect for the bent portion 222.

[0118] When the first substrate layer 33, which is at least partially located in the overlap region M, provides support for the bent portion 222, and / or when the second substrate layer 43, which is at least partially located in the overlap region M, provides support for the bent portion 222, the overlap region M extends at least partially to the bent portion 222 and is able to support the bent portion 222.

[0119] Optionally, the overlapping area M is located only at the bend 222 and covers at least a portion of the bend 222 along the extension direction of the tab 22 (specifically as shown in the figure). Figure 4 (as shown); Optionally, the overlapping area M is located only at the bend 222 and covers most of the bend 222 along the extension direction of the tab 22 (specifically as shown). Figure 8 (as shown); Optionally, the overlapping area M extends along the tab 22 and covers part of the connecting portion 221 and part of the bent portion 222 (specifically as shown). Figure 9 (As shown).

[0120] Preferably, the overlapping area M extends along the tab 22 and covers part of the connecting portion 221, all of the bent portion 222, and part of the root portion 223 (specifically as shown in the figure). Figure 10 (As shown). This design increases the area covered by the overlap region M, thereby achieving better insulation. Please refer to... Figure 15 and Figure 16 In some embodiments, in the overlapping region M, the first substrate layer 33 is located between the bend 222 and the second substrate layer 43; the thickness of the first substrate layer 33 is greater than the thickness of the second substrate layer 43 (specifically as follows). Figure 15 As shown), the first substrate layer 33 provides support, or the thickness of the second substrate layer 43 is greater than the thickness of the first substrate layer 33 (specifically as shown). Figure 16As shown, the second substrate layer 43 provides support. Whether the support is provided solely by the first substrate layer 33 or jointly by the first substrate layer 33 and the second substrate layer 43, it helps reduce the risk of deformation of the bent portion 222. It can be understood that in the overlap region M, when the first substrate layer 33 is located between the bent portion 222 and the second substrate layer 43, and the thickness of the first substrate layer 33 is greater than the thickness of the second substrate layer 43, the first substrate layer 33 provides support. In fact, the support for the bent portion 222 is provided solely by the first substrate layer 33. In the overlap region M, when the first substrate layer 33 is located between the bent portion 222 and the second substrate layer 43, and the thickness of the second substrate layer 43 is greater than the thickness of the first substrate layer 33, the second substrate layer 43 provides support. In fact, the second substrate layer 43 indirectly acts on the bent portion 222 through the first substrate layer 33, so that the support for the bent portion 222 is provided jointly by both the first substrate layer 33 and the second substrate layer 43.

[0121] Please see Figure 17 and Figure 18 In some embodiments, in the overlapping region M, the second substrate layer 43 is located between the bend 222 and the first substrate layer 33; the thickness of the first substrate layer 33 is greater than the thickness of the second substrate layer 43 (specifically as follows). Figure 17 As shown), the first substrate layer 33 provides support, or the thickness of the second substrate layer 43 is greater than the thickness of the first substrate layer 33 (specifically as shown). Figure 18 As shown, the second substrate layer 43 provides support. In this embodiment, in the overlap region M, when the second substrate layer 43 is located between the bent portion 222 and the first substrate layer 33, and the thickness of the first substrate layer 33 is greater than the thickness of the second substrate layer 43, the first substrate layer 33 provides support. In fact, the first substrate layer 33 indirectly acts on the bent portion 222 through the second substrate layer 43, so that the support force for the bent portion 222 is provided jointly by the first substrate layer 33 and the second substrate layer 43. In the overlap region M, when the second substrate layer 43 is located between the bent portion 222 and the first substrate layer 33, and the thickness of the second substrate layer 43 is greater than the thickness of the first substrate layer 33, the second substrate layer 43 provides support, that is, the support force for the bent portion 222 is provided solely by the second substrate layer 43. Regardless of whether the support force is provided solely by the second substrate layer 43 or jointly by the first substrate layer 33 and the second substrate layer 43, it can reduce the risk of deformation of the bent portion 222.

[0122] Furthermore, in the two embodiments described above, when the thickness of the first substrate layer 33 is greater than the thickness of the second substrate layer 43, it can be understood that the second substrate layer 43 is thinner than the first substrate layer 33. This can reduce the tearing force of the tab support 70 on the second protective member 40 during the pressing process, thereby playing a role in protecting the diaphragm.

[0123] When the thickness of the second substrate layer 43 is greater than the thickness of the first substrate layer 33, it can be understood that the second substrate layer 43 is designed to be relatively thicker, and the first substrate layer 33 is designed to be relatively thinner. The relatively thicker second substrate layer 43 can improve the support of the tab support 70 for the tab 22, preventing the tab 22 from being inserted upside down; the relatively thinner first substrate layer 33 can reduce the cutting force of the tab support 70 on the tab 22, thereby protecting the tab 22. The relatively thinner first substrate layer 33 can provide more space for folding the tab 22, preventing the risk of the tab 22 being inserted upside down.

[0124] Please see Figures 19 to 22 In some embodiments, the thickness of the first substrate layer 33 is h11, h11≥0.01mm; and / or, the thickness of the second substrate layer 43 is h21, 0.01mm≤h21≤0.1mm.

[0125] Where h11 can be, but is not limited to, 0.01mm, 0.02mm, 0.05mm, 0.08mm, 0.1mm, etc. and h21 can be, but is not limited to, 0.01mm, 0.02mm, 0.05mm, 0.08mm, 0.1mm, etc.

[0126] Specifically, if the thickness of the first substrate layer 33 is too thin, its strength will be too weak, making it easy to break and causing weld slag to puncture and leak, resulting in a short circuit. Therefore, h11 is designed to be ≥0.01mm. However, it is worth noting that the thickness of the first substrate layer 33 should not be too large. If the thickness is too large, it will increase its proportion in the width direction Z of the electrode assembly 20, affecting the energy density of the battery cell 100.

[0127] Specifically, if the second substrate layer 43 is too thin, it is easily broken, leading to production defects. If the second substrate layer 43 is too thick, it will increase its proportion in the width direction Z and / or thickness direction Y of the electrode assembly 20, reducing space utilization. Furthermore, if the second substrate layer 43 is too thick, it will cause excessive pressure on the electrode assembly 20, resulting in wrinkles in the electrode sheet or separator, and reducing the safety and reliability of the battery cell 100. Based on the above reasons, the thickness is designed to be 0.01mm ≤ h21 ≤ 0.1mm.

[0128] Please see Figure 20 and Figure 23Preferably, 0.025mm ≤ h11 ≤ 0.1mm. In specific embodiments, h11 can be, but is not limited to, 0.025mm, 0.05mm, 0.075mm, 0.08mm, 0.1mm, etc. In this embodiment, when the thickness of the first substrate layer 33 is within this range, the first substrate layer 33 and the first adhesive layer 34 have sufficient supporting strength to jointly support the tab 22 and prevent the tab 22 from being inserted backwards into the main body 21, thereby eliminating the need for the tab support member 70 and improving space utilization. After removing the tab support member 70 from the battery cell 100, the assembly steps and process flow of the battery cell 100 are simpler.

[0129] Please see Figures 19 to 22 In some embodiments, the thickness of the first adhesive layer 34 is h12, 0.025mm≤h12≤0.1mm, and / or the thickness of the second adhesive layer 44 is h22, 0.005mm≤h22≤0.1mm.

[0130] In specific implementations, h12 may be, but is not limited to, 0.025mm, 0.05mm, 0.075mm, 0.08mm, 0.1mm, etc., and h22 may be, but is not limited to, 0.005mm, 0.007mm, 0.008mm, 0.01mm, 0.03mm, 0.08mm, 0.1mm, etc.

[0131] If the thickness of the first adhesive layer 34 is too thin, it will not be able to prevent solder slag from falling off; if the thickness of the first adhesive layer 34 is too thick, it will occupy too much space in the width direction Z of the electrode assembly 20, reducing space utilization. Based on this, the thickness is designed to be 0.025mm≤h12≤0.1mm. Within this range, the thickness of the first adhesive layer 34 is ensured to have sufficient adhesive thickness to prevent solder slag from falling off, while occupying less space in the width direction Z of the electrode assembly 20, resulting in high space utilization.

[0132] If the second adhesive layer 44 is too thin, it cannot be stably attached to the main body 21 and is prone to falling off. If the second adhesive layer 44 is too thick, it will occupy more space in the thickness direction Y of the electrode assembly 20, reducing space utilization. Based on this, the design is 0.005mm≤h22≤0.1mm. Within this range, the thickness of the second adhesive layer 44 ensures that it has sufficient adhesive thickness to adhere to the main body 21 while occupying less space and achieving high space utilization.

[0133] like Figure 24As shown, in some embodiments, the first adhesive portion 31 bonds to and covers at least a portion of the connection portion 221 located between the first welding area 2211 and the bend 222. This design can increase the bonding area between the first adhesive portion 31 and the tab 22, thereby better securing the first protective member 30 and reducing the risk of the first protective member 30 falling off.

[0134] like Figure 4 and Figure 25 As shown, in some embodiments, the second adhesive portion 41 extends to the root portion 223, and the second adhesive portion 41 adhesively bonds to and covers a portion of the root portion 223. That is, the second adhesive portion 41 extends from the main body portion 21 to the root portion 223.

[0135] On the one hand, this design increases the bonding area between the second adhesive portion 41 and the electrode assembly 20, thereby better securing the second protective member 40 and reducing the risk of the second protective member 40 detaching. On the other hand, this design also protects the root 223 of the tab 22, reducing the risk of the tab 22 breaking at the root 223.

[0136] like Figure 23 and Figure 26 As shown, in some embodiments, along the extension direction of the tab 22 (e.g. Figure 23 (As indicated by the middle arrow N), the length of the first substrate layer 33 is a, the length of the first adhesive part 31 is b, and b ≥ a / 2.

[0137] It can be understood that the length of the first substrate layer 33 is the dimension of the first substrate layer 33 in the extension direction of the tab 22.

[0138] In a specific implementation, b can be, but is not limited to, a / 2, a / 3, a / 4, a, etc.

[0139] By designing b ≥ a / 2, the length of the first adhesive part 31 on the first substrate layer 33 is relatively large, resulting in a larger bonding area with the tab 22. This helps improve the bonding stability of the first protective member 30 and prevents it from falling off. It is worth mentioning that the maximum value of b is equal to a.

[0140] Please see Figure 8 and Figure 35 In some embodiments, the first non-adhesive portion 32 and the second non-adhesive portion 42 overlap to form an overlap area M, thereby preventing the first protective member 30 and the second protective member 40 from adhering together. Further, the overlap length is e, where c / 5 ≤ e ≤ 2c / 3, and c is the length of the tab 22 (where c is the length of the tab 22). Figure 35 (The sum of c1 and c2), and / or, e≥5mm.

[0141] It can be understood that the length of the overlapping area M is the dimension of the overlapping area M in the extension direction of the tab 22. The length of the tab 22 is the dimension of the surface of the tab 22 facing the first protective member 30 in the extension direction of the tab 22.

[0142] In specific implementations, e can be, but is not limited to, c / 5, c / 4, c / 3, 2c / 3, etc., or e can be, but is not limited to, 5mm, 6mm, 7mm, etc.

[0143] If the length of the overlapping region M is too small, the first non-bonded portion 32 and the second non-bonded portion 42 of the overlapping region M will easily fold over, thus failing to fully cover the tab 22 and reducing insulation. In this case, e ≥ c / 5 or e ≥ 5 mm is set. If the length of the overlapping region M is too large, the overlapping region M will occupy a large space in the width direction Z of the electrode assembly 20, reducing space utilization. Based on this consideration, e ≤ 2c / 3 is set.

[0144] Please see Figure 8 In some embodiments, the bonding strength between the first adhesive portion 31 and the first welding area 2211 is P1, and the bonding strength between the second adhesive portion 41 and the main body portion 21 is P2; P1 ≥ P2; and / or, 2N / 25mm ≤ P1 ≤ 15N / 25mm, and / or, 1N / 25mm ≤ P2 ≤ 7N / 25mm. In specific embodiments, P1 may be, but is not limited to, 2N / 25mm, 4N / 25mm, 8N / 25mm, 10N / 25mm, 15N / 25mm, etc., and P2 may be, but is not limited to, 1N / 25mm, 3N / 25mm, 4N / 25mm, 6N / 25mm, 7N / 25mm, etc.

[0145] The first adhesive portion 31 is disposed on the solder mark of the first welding area 2211, and it requires greater adhesive force to prevent slag leakage. The second adhesive portion 41 is disposed on the main body portion 21, and its lower adhesive force with the main body portion 21 is beneficial for electrolyte wetting of the electrode assembly 20. Based on this, it is designed that P1≥P2.

[0146] Furthermore, excessive bonding strength of the first bonding portion 31 can easily lead to tearing of the tab 22, while insufficient bonding strength can cause the first bonding portion 31 to shift, resulting in slag leakage. Therefore, the design is 2N / 25mm ≤ P1 ≤ 15N / 25mm.

[0147] Furthermore, excessive bonding strength of the second bonding part 41 can easily lead to poor electrolyte wetting or even tearing of the electrode or diaphragm. Insufficient bonding strength of the second bonding part 41 can result in poor fixation of the second bonding part 41 and easily form wrinkles that compress the main body 21. Based on this, the design is 1N / 25mm≤P2≤7N / 25mm.

[0148] In some embodiments, the Rockwell hardness of the first protective member 30 is K1, the Rockwell hardness of the second protective member 40 is K2, K1≥K2, and / or, K1≥100, and / or, K2≥80.

[0149] In specific implementations, K1 can be, but is not limited to, 100, 130, 200, 300, etc., and P2 can be, but is not limited to, 80, 90, 100, 110, etc.

[0150] In the embodiment with tab support 70, when the electrode assembly 20 is unfolded before core closing, the tab support 70 directly presses against the first protective member 30 and is easily damaged. Therefore, K1≥K2 is designed.

[0151] Furthermore, in order to reduce the risk of the first protective component 30 and the second protective component 40 being crushed and cracked due to the pressure of the tab support component 70, the Rockwell hardness of the first protective component 30 and the second protective component 40 is relatively large, so K1≥100 and K2≥80 are set.

[0152] In some embodiments, the tensile strength of the first protective member 30 is M1, the tensile strength of the second protective member 40 is M2, M1 < M2, and / or, M1 > 50 MPa, and / or, M2 > 50 MPa.

[0153] In a specific implementation, M1 may be, but is not limited to, 50, 60, 80, 150, 200, etc., and M2 may be, but is not limited to, 50, 70, 80, 150, 200, etc.

[0154] If the tensile strength of the first protective component 30 and the second protective component 40 is too low, they are prone to breakage, leading to the failure of their protective and insulating functions. In this application, by designing M1 > 50 MPa and M2 > 50 MPa, the first protective component 30 and the second protective component 40 have greater strength and are less prone to breakage.

[0155] Preferably, the tensile strength of the first protective member 30 is 50 MPa ≤ M1 ≤ 200 MPa. Increasing the tensile strength of the first protective member 30 often means increasing its thickness, which can easily lead to an increase in the space occupied by the first protective member 30 in the width direction Z of the electrode assembly 20. Therefore, based on this consideration, the design is 50 MPa ≤ M1 ≤ 200 MPa. This ensures sufficient tensile strength for the first protective member 30, reducing the risk of breakage while also minimizing its footprint.

[0156] Preferably, the tensile strength of the second protective component 40 is 50 MPa ≤ M2 ≤ 150 MPa. Increasing the tensile strength of the second protective component 40 often means increasing its thickness, which can lead to an increase in the space occupied by the second protective component 40. Furthermore, an increased thickness of the second protective component 40 makes it more susceptible to being scraped by the tab support 70 when it is pressed down, potentially tearing the tab 22 or the separator. Therefore, based on this consideration, the design is 50 MPa ≤ M2 ≤ 150 MPa. This ensures sufficient tensile strength for the second protective component 40, reducing the risk of breakage and also minimizing the risk of scraping against the tab support 70, thus improving the performance of the battery 1000.

[0157] Furthermore, considering that the second protective component 40 needs to withstand greater tensile force than the first protective component 30 during the battery 1000 manufacturing process (such as the core assembly and the pressing process of the tab support component 70), M1 is designed to be less than M2.

[0158] Please see Figure 2 , Figure 27 , Figure 29 and Figure 30 Optionally, the electrode lead-out portion 10 includes an adapter piece 11 and an electrode post 12. The adapter piece 11 and the electrode post 12 are welded to form a second welding area 2212. The second welding area 2212 and the first welding area 2211 are along the width direction of the electrode tab 22 (e.g., ...). Figure 27 (As indicated by the middle arrow P) Layout. The first adhesive part 31 may only bond the first welding area 2211, without bonding the second welding area 2212 (as shown by...). Figure 27 As shown), it is also possible to bond both the first welding area 2211 and the second welding area 2212 (as shown). Figure 30 (As shown)

[0159] Preferably, the first adhesive portion 31 adheres to and covers at least a portion of the second welding area 2212, so that the first adhesive portion 31 can also fix the welding slag in the second welding area 2212, thereby reducing the risk of welding slag falling off the second welding area 2212 and providing better insulation. In this embodiment, in addition to adhering to the first welding area 2211, the first adhesive portion 31 can adhere to and cover part of the second welding area 2212, or it can adhere to and cover the entire second welding area 2212. More preferably, the first adhesive portion 31 adheres to and covers the entire second welding area 2212, thereby better fixing the welding slag in the second welding area 2212 and providing better insulation.

[0160] Furthermore, when the first protective member 30 replaces the tab support member 70 and is also used to support the tab 22, if the first adhesive part 31 is bonded and covers at least part of the second welding area 2212, the contact area between the first adhesive part 31 and the adapter piece 11 is larger, and the first adhesive part 31 can be bonded more firmly, thereby better supporting the tab 22.

[0161] like Figure 30 As shown, in some embodiments, the first protective member 30 covers and bonds the entire adapter piece 11 to ensure insulation between the adapter piece 11 and the main body 21.

[0162] like Figure 4 , Figures 28 to 30 As shown, the battery cell 100 includes a first electrode assembly 20a and a second electrode assembly 20b stacked on top of each other; optionally, the two first protective members 30 connected to the two tabs 22 of the same polarity in the first electrode assembly 20a and the second electrode assembly 20b can be separated and spaced apart (e.g., Figure 28 and Figure 29 As shown), it can also be set up as a whole (as shown). Figure 4 and Figure 30 (As shown).

[0163] It should be noted that the two tabs 22 with the same polarity can be the positive tab 22a of the first electrode assembly 20a and the positive tab 22a of the second electrode assembly 20b, or they can be the negative tab 22b of the first electrode assembly 22a and the negative tab 22b of the second electrode assembly 20b. This arrangement can be applied only to the first protective element 30 of the positive tab 22a, only to the first protective element 30 of the negative tab 22b, or to both; it is not mandatory here. Taking the positive tab 22a as an example, the first protective element 30 bonded to the positive tab 22a in the first electrode assembly 22a and the first protective element 30 bonded to the positive tab 22a in the second electrode assembly 20b can be separate and spaced apart, or they can be integrated into one piece.

[0164] Preferably, the two first protective members 30 connected to the two tabs 22 of the same polarity in the first electrode assembly 20a and the second electrode assembly 20b are integrally arranged. This design can reduce assembly steps and reduce assembly difficulty.

[0165] Optionally, the two first protective members 30 connected to the two tabs 22 with opposite polarities in the same electrode assembly 20 can be integrally set (e.g., Figure 31 As shown), they can also be set separately (see details). Figure 32 (As shown).

[0166] It should be noted that the two tabs 22 with opposite polarities in the same electrode assembly 20 can be the positive tab 22a and negative tab 22b of the first electrode assembly 20a, or the positive tab 22a and negative tab 22b of the second electrode assembly 20b. This setting can apply only to the first protective element 30 on the first electrode assembly 20a, only to the first protective element 30 on the second electrode assembly 20b, or it can apply to both the first protective element 30 on the first electrode assembly 20a and the first protective element 30 on the second electrode assembly 20b; this is not mandatory.

[0167] Preferably, the two first protective members 30 connected to the tabs 22 of opposite polarity in the same electrode assembly 20 are separately arranged. This reduces the likelihood of the positive tab 22a and negative tab 22b within the same electrode assembly 20 being torn apart by the first protective members 30, thus better protecting the positive tab 22a and negative tab 22b. Furthermore, it reduces the obstruction of the electrode assembly 20 by the first protective members 30, allowing the electrolyte to fully wet the electrode assembly 20.

[0168] like Figure 33 As shown, optionally, the two second protective members 40 connected to the two tabs 22 with opposite polarities in the same electrode assembly 20 can be integrally set or separately set, as shown in the figure. Figure 32 As shown.

[0169] It should be noted that this setting may apply only to the second protective element 40 on the first electrode assembly 20a or only to the second protective element 40 on the second electrode assembly 20b, or it may apply to both the second protective element 40 on the first electrode assembly 20a and the second protective element 40 on the second electrode assembly 20b. This is not mandatory.

[0170] Preferably, the two second protective members 40 connected to the opposite polarity tabs 22 in the same electrode assembly 20 are separately arranged. This reduces the risk of the positive tab 22a and negative tab 22b within the same electrode assembly 20 being torn apart by the second protective members 40, thus providing better protection for the positive tab 22a and negative tab 22b. Furthermore, it reduces the obstruction of the electrode assembly 20 by the second protective members 40, allowing the electrolyte to fully wet the electrode assembly 20.

[0171] like Figure 2 , Figure 30 and Figure 34As shown, in some embodiments, the battery cell 100 further includes a housing 50 and an explosion-proof valve 60. The housing 50 includes a shell 51 and a top cover 52. The shell 51 is used to accommodate the electrode assembly 20, the first protective member 30 and the second protective member 40. The top cover 52 is used to cover the shell 51. The explosion-proof valve 60 is disposed on the top cover 52. In the thickness direction of the top cover 52, the projection of the explosion-proof valve 60 does not overlap with the projection of the first protective member 30.

[0172] With this design, the explosion-proof valve 60 can be prevented from being blocked by the first protective component 30. In the event of thermal runaway of the battery cell 100, the high-temperature flue gas can be smoothly discharged through the explosion-proof valve 60, thus ensuring that there is a sufficient exhaust path when the battery cell 100 experiences thermal runaway, thereby improving the safety of the battery cell 100.

[0173] Please refer to 26. Figure 32 and Figure 35 The following is a detailed description of the process of combining the first electrode assembly 20a and the second electrode assembly 20b.

[0174] Before core assembly, the first electrode assembly 20a and the second electrode assembly 20b are unfolded. At this time, the connecting portion 221 of the tab 22 is approximately perpendicular to the thickness direction Y of the electrode assembly 20. During core assembly, the first electrode assembly 20a and the second electrode assembly 20b are stacked along the thickness direction Y of the electrode assembly 20, and the connecting portion 221 is approximately parallel to the thickness direction Y of the electrode assembly 20, thus completing the core assembly.

[0175] like Figure 36 As shown, this application also provides a battery 1000, which includes a battery cell 100 as described in any of the above embodiments.

[0176] In some embodiments, the battery 1000 further includes an outer casing 200, which includes a first portion 210 and a second portion 220. The first portion 210 and the second portion 220 enclose a space for placing the battery cell 100, so as to reduce external interference to the battery cell 100.

[0177] like Figure 37 As shown, this application also provides an electrical device 10000, which includes a battery 1000 as described in any of the above embodiments, the battery 1000 being used to provide electrical energy to the electrical device 10000.

[0178] The electrical device 10000 can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0179] It should be understood that the technical solutions described in the embodiments of this application are not limited to the electrical device 10000 described above.

[0180] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0181] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A battery cell, characterized in that, The battery cell includes: Electrode lead-out section (10) is used to draw out the electrical energy of the battery cell; The electrode assembly (20) includes a main body (21) and an electrode tab (22). The electrode tab (22) includes a connecting part (221), a bending part (222), and a root part (223). The connecting part (221) is welded to the electrode lead-out part (10) to form a first welding area (2211). The root part (223) is connected to the main body (21). The bending part (222) is connected between the connecting part (221) and the root part (223). The electrode tab (22) bends at the bending part (222). A first protective member (30) is at least partially located between the main body (21) and the connecting portion (221). The first protective member (30) includes a first substrate layer (33) and a first adhesive layer (34) stacked together. The first adhesive layer (34) and the first substrate layer (33) form a first adhesive portion (31). The first adhesive portion (31) at least bonds to and covers a portion of the first welding area (2211). The second protective member (40) is located at least partially between the main body (21) and the connecting part (221). The second protective member (40) includes a second substrate layer (43) and a second adhesive layer (44) stacked together. The second adhesive layer (44) and the second substrate layer (43) form a second adhesive part (41). The second adhesive part (41) at least bonds to and covers a portion of the main body (21). The first substrate layer (33) and the second substrate layer (43) have different thicknesses, and along the extension direction of the tab (22), the first substrate layer (33) and the second substrate layer (43) have an overlapping area (M); Wherein, the first substrate layer (33) has a first non-adhesive portion (32) extending beyond the first adhesive layer (34), and / or, the second substrate layer (43) has a second non-adhesive portion (42) extending beyond the second adhesive layer (44).

2. The battery cell according to claim 1, characterized in that, The first non-adhesive portion (32) includes the first substrate layer (33) located in the overlapping area (M); and / or, the second non-adhesive portion (42) includes the second substrate layer (43) located in the overlapping area (M).

3. The battery cell according to claim 2, characterized in that, The first substrate layer (33), which is at least partially located in the overlapping area (M), provides support for the bent portion (222), and / or the second substrate layer (43), which is at least partially located in the overlapping area (M), provides support for the bent portion (222).

4. The battery cell according to claim 3, characterized in that, In the overlapping area (M), the first substrate layer (33) is located between the bent portion (222) and the second substrate layer (43); The thickness of the first substrate layer (33) is greater than the thickness of the second substrate layer (43), and the first substrate layer (33) provides the supporting force; or the thickness of the second substrate layer (43) is greater than the thickness of the first substrate layer (33), and the second substrate layer (43) provides the supporting force.

5. The battery cell according to claim 3, characterized in that, In the overlapping area (M), the second substrate layer (43) is located between the bent portion (222) and the first substrate layer (33); The thickness of the first substrate layer (33) is greater than the thickness of the second substrate layer (43), and the first substrate layer (33) provides the supporting force; or the thickness of the second substrate layer (43) is greater than the thickness of the first substrate layer (33), and the second substrate layer (43) provides the supporting force.

6. The battery cell according to any one of claims 1 to 5, characterized in that, The thickness of the first substrate layer (33) is h11, h11≥0.01mm, and / or the thickness of the second substrate layer (43) is h21, 0.01mm≤h21≤0.1mm.

7. The battery cell according to claim 6, characterized in that, 0.025mm≤h11≤0.1mm.

8. The battery cell according to any one of claims 1 to 5, characterized in that, The thickness of the first adhesive layer (34) is h12, 0.025mm≤h12≤0.1mm, and / or the thickness of the second adhesive layer (44) is h22, 0.005mm≤h22≤0.1mm.

9. The battery cell according to any one of claims 1 to 5, characterized in that, The first adhesive portion (31) adhesively bonds and covers at least a portion of the connecting portion (221) located between the first welding area (2211) and the bending portion (222).

10. The battery cell according to any one of claims 1 to 5, characterized in that, The second adhesive portion (41) extends to the root portion (223), and the second adhesive portion (41) adhesively bonds to and covers a portion of the root portion (223).

11. The battery cell according to claim 1, characterized in that, Along the extension direction of the tab (22), the length of the first substrate layer (33) is a, the length of the first adhesive portion (31) is b, and b≥a / 2.

12. The battery cell according to claim 1, characterized in that, The first non-adhesive portion (32) overlaps with the second non-adhesive portion (42) to form the overlapping area (M), the length of the overlap is e, c / 5≤e≤2c / 3, c is the length of the tab (22), and / or e≥5mm.

13. The battery cell according to claim 1, characterized in that, The bonding strength between the first adhesive part (31) and the first welding area (2211) is P1, and the bonding strength between the second adhesive part (41) and the main body part (21) is P2; P1 ≥ P2; and / or, 2N / 25mm ≤ P1 ≤ 15N / 25mm, and / or, 1N / 25mm ≤ P2 ≤ 7N / 25mm; and / or, The Rockwell hardness of the first protective element (30) is K1, and the Rockwell hardness of the second protective element (40) is K2, where K1 ≥ K2, and / or K1 ≥ 100, and / or K2 ≥ 80; and / or, The tensile strength of the first protective member (30) is M1, and the tensile strength of the second protective member (40) is M2, M1 < M2, and / or, M1 > 50 MPa, and / or, M2 > 50 MPa.

14. The battery cell according to claim 1, characterized in that, The electrode lead-out portion (10) includes an adapter piece (11) and a pole piece (12). The adapter piece (11) and the pole piece (12) are welded to form a second welding area (2212). The second welding area (2212) and the first welding area (2211) are arranged along the width direction of the tab (22). The first adhesive portion (31) is bonded to and covers at least part of the second welding area (2212).

15. The battery cell according to claim 1, characterized in that, The battery cell includes a first electrode assembly (20a) and a second electrode assembly (20b) stacked on top of each other; wherein, The two first protective members (30) that are connected to the two tabs (22) of the same polarity in the first electrode assembly (20a) and the second electrode assembly (20b) are integrally formed; And / or, the two first protective members (30) connected to the two tabs (22) of opposite polarity in the same electrode assembly (20) are respectively arranged separately; And / or, the two second protective members (40) connected to the two tabs (22) of opposite polarity in the same electrode assembly (20) are respectively arranged separately.

16. The battery cell according to claim 1, characterized in that, The battery cell also includes a housing (50) and an explosion-proof valve (60). The housing (50) includes a shell (51) and a top cover (52). The shell (51) is used to accommodate the electrode assembly (20), the first protective member (30) and the second protective member (40). The top cover (52) is used to cover the shell (51). The explosion-proof valve (60) is disposed on the top cover (52). In the thickness direction of the top cover (52), the projection of the explosion-proof valve (60) does not overlap with the projection of the first protective member (30).

17. A battery, characterized in that, The battery comprises a battery cell as described in any one of claims 1 to 16 above.

18. An electrical appliance, characterized in that, The electrical device includes the battery as described in claim 17.

Images