Battery cell, battery pack, and electric device

Abstract

The application relates to the battery technical field and discloses a battery monomer, a battery pack and a power utilization device. The battery monomer comprises a shell, an electrode assembly and a first electrode terminal. The shell has a containing space. The shell comprises a first wall. The electrode assembly is arranged in the containing space. The first electrode terminal is arranged on the first wall. The first electrode terminal comprises a first body part and a first extension part. The first extension part is protrusively arranged on the first body part along a first direction. The first direction is perpendicular to the thickness direction of the first wall. The first wall is provided with a first through hole. The first through hole penetrates the first wall along the thickness direction of the first wall to electrically connect the first body part and the electrode assembly. The first extension part is oppositely arranged with the center line of the first through hole along the first direction. The first extension part is beneficial to improving the heat dissipation performance of the first electrode terminal. The first extension part is oppositely arranged with the center line of the first through hole along the first direction, so that the flow path is reduced, and the influence on current transmission is reduced.

Description

Technical Field

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

[0002] With the rapid development of science and technology, energy issues are becoming increasingly prominent. As an important energy conversion and storage device, batteries play an indispensable role in many fields such as mobile devices, electric vehicles, and energy storage power stations. Therefore, people have put forward higher requirements for the performance of batteries.

[0003] Currently, current is transmitted through electrode terminals in battery cells. Due to the poor heat dissipation performance of the electrode terminals, heat is easily concentrated inside the battery cell. In order to improve the heat dissipation performance of the electrode terminals, heat dissipation parts are usually set on the electrode terminals. However, the existing heat dissipation part design tends to result in a long flow path, which affects the current transmission. Utility Model Content

[0004] This application provides a battery cell, a battery pack, and an electrical device. Part of the heat from the first body portion of the first electrode terminal can be dissipated outward through the first extension portion. The first extension portion effectively expands the heat dissipation area of ​​the first electrode terminal, which is beneficial to improving the heat dissipation performance of the first electrode terminal. At the same time, the first extension portion is arranged opposite to the center line of the first through hole along the first direction, which can ensure that the current flows from the electrode assembly to the first extension portion along the shortest straight distance, reducing the flow path. Therefore, while satisfying the heat dissipation performance, it is also beneficial to reduce the impact on current transmission.

[0005] To achieve the above objectives, the main technical solutions adopted in this application include:

[0006] In a first aspect, embodiments of this application provide a battery cell, the battery cell comprising:

[0007] The outer casing has a receiving space, and the outer casing includes a first wall;

[0008] Electrode assembly, disposed within the receiving space;

[0009] A first electrode terminal is disposed on a first wall. The first electrode terminal includes a first body portion and a first extension portion. Along a first direction, the first extension portion protrudes from the first body portion. The first direction is perpendicular to the thickness direction of the first wall.

[0010] The first wall is provided with a first through hole, which penetrates the first wall along the thickness direction to make the first body part electrically connected to the electrode assembly. Along the first direction, the first extension part is arranged opposite to the center line of the first through hole.

[0011] The battery cell described above includes a first electrode terminal comprising a first body portion and a first extension portion. The first body portion is used for electrical connection with the electrode assembly, and therefore heat is mainly generated in the first body portion. In this application, the first extension portion protrudes from the first body portion along a first direction. With this arrangement, some of the heat from the first body portion can be dissipated outward through the first extension portion. The first extension portion effectively expands the heat dissipation area of ​​the first electrode terminal, which is beneficial to improving the heat dissipation performance of the first electrode terminal. At the same time, the first extension portion is arranged opposite to the center line of the first through hole along the first direction, which ensures that the current flows from the electrode assembly to the first extension portion along the shortest straight distance, reducing the flow path. Therefore, while meeting the heat dissipation performance requirements, it is also beneficial to reduce the impact on current transmission.

[0012] Secondly, embodiments of this application provide a battery pack, including the battery cells in the first aspect of this application.

[0013] Thirdly, embodiments of this application provide an electrical device, including a single battery cell or a battery pack as described in the first aspect of this application. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0015] Figure 1 A perspective view of a battery cell provided in the first embodiment of this application;

[0016] Figure 2 A top view of a battery cell provided in the first embodiment of this application;

[0017] Figure 3 yes Figure 2 Sectional view at point AA;

[0018] Figure 4 A top view of a battery cell provided in the second embodiment of this application;

[0019] Figure 5 A top view of a battery cell provided in the third embodiment of this application;

[0020] Figure 6 A top view of a battery cell provided in the fourth embodiment of this application;

[0021] Figure 7A top view of a battery cell provided in the fifth embodiment of this application;

[0022] Figure 8 A top view of a battery cell provided in the sixth embodiment of this application;

[0023] Figure 9 This is a top view of a battery pack provided in one embodiment of this application.

[0024] [Explanation of Labels in the Attached Image]

[0025] Battery pack 1000;

[0026] 100 for a single battery cell;

[0027] 1. Outer shell; 11. Accommodating space; 12. First wall; 121. First through hole; 122. Second through hole; 123. Liquid injection hole; 124. Pressure relief mechanism; 125. First center line; 126. Second center line;

[0028] Electrode assembly 2;

[0029] First electrode terminal 3; First body portion 31; First connecting section 311; Second connecting section 312; First extension portion 32;

[0030] Second electrode terminal 4; Second body portion 41; Third connecting section 411; Fourth connecting section 412; Second extension portion 42;

[0031] First insulating component 5;

[0032] First busbar 200;

[0033] Second busbar 300;

[0034] First direction X; second direction Y. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0037] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0039] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0040] In this application, "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more (including two), and "multiple pieces" refers to two or more (including two).

[0041] With the rapid development of science and technology, energy issues are becoming increasingly prominent. As an important energy conversion and storage device, batteries play an indispensable role in many fields such as mobile devices, electric vehicles, and energy storage power stations. Therefore, people have put forward higher requirements for the performance of batteries.

[0042] Currently, current is transmitted through electrode terminals in battery cells. Due to the poor heat dissipation performance of the electrode terminals, heat is easily concentrated inside the battery cell. In order to improve the heat dissipation performance of the electrode terminals, heat dissipation parts are usually set on the electrode terminals. However, the existing heat dissipation part design tends to result in a long flow path, which affects the current transmission.

[0043] In view of this, this application proposes a battery cell 100, in which the first electrode terminal 3 includes a first body portion 31 and a first extension portion 32. The first body portion 31 is used for electrical connection with the electrode assembly 2, so heat is mainly generated in the first body portion 31. In this application, the first extension portion 32 protrudes from the first body portion 31 along the first direction X. With this arrangement, some of the heat from the first body portion 31 can be dissipated outward through the first extension portion 32. The first extension portion 32 effectively expands the heat dissipation area of ​​the first electrode terminal 3, which is beneficial to improving the heat dissipation performance of the first electrode terminal 3. At the same time, along the first direction X, the first extension portion 32 is arranged opposite to the center line of the first through hole 121. This ensures that the current flows from the electrode assembly 2 to the first extension portion 32 along the shortest straight distance, reducing the flow path. Therefore, while meeting the heat dissipation performance, it is also beneficial to reduce the impact on current transmission.

[0044] As an example, a battery cell includes a cell formed by using positive and negative electrode plates as electrochemical material carriers, separating the positive and negative electrode plates through a separator to prevent short circuits, using an electrolyte as an ion transport carrier, achieving structural protection through a battery casing, and connecting to an external circuit through terminals.

[0045] In some embodiments, the positive electrode sheet includes a positive current collector having a plurality of surfaces, wherein at least one surface is provided with a positive active material.

[0046] As an example, the positive electrode active material is located on the surface of the positive electrode current collector along its own thickness direction.

[0047] As an example, the positive electrode current collector can be a metal foil or a composite current collector. When the positive electrode current collector includes a metal foil, it can be at least one of the following: silver-plated aluminum, silver-plated stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium. When the positive electrode current collector includes a composite current collector, the composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0048] As an example, positive electrode active materials include, but are not limited to, the following materials: lithium phosphates, lithium transition metal oxides and their respective modified compounds, and other conventional materials that can be used as positive electrode active materials for batteries may also be used.

[0049] In some embodiments, the negative electrode sheet includes a negative electrode current collector and a negative electrode active material. The negative electrode current collector may be a metal foil or a composite current collector. When the negative electrode current collector includes a metal foil, it may be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, or at least one of carbon, nickel, or titanium.

[0050] As an example, the negative electrode active material is disposed on the surface of the negative electrode current collector along its thickness direction.

[0051] As examples, negative electrode active materials include, but are not limited to, the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, and may also employ other conventional materials known in the art that can be used as battery negative electrode active materials. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys, but this application is not limited to these materials. These negative electrode active materials may be used alone or in combination of two or more.

[0052] In some embodiments, the diaphragm can be any known porous diaphragm with good chemical and mechanical stability.

[0053] As an example, the main materials of the separator include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramics. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation. The separating component can be a separate component located between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0054] In some embodiments, the positive electrode, negative electrode, and separator form a stacked structure. A stacked structure refers to the stacking of individual sheet-like positive electrode, negative electrode, and separator structures; the positive and negative electrode sheets are discontinuous, and adjacent layers are discontinuous; additionally, in this application, the separator can also be a single sheet, discontinuous; in another embodiment, the separator can be continuous, while the positive and negative electrode sheets are discontinuous, thereby forming a Z-shaped stacked structure.

[0055] In some embodiments, the battery casing includes at least one of a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite battery casing), or an aluminum-plastic film. The battery casing can encapsulate components such as the positive electrode, negative electrode, and separator.

[0056] The following detailed description of the battery cell 100, battery pack 1000, and electrical device in this application is based on the accompanying drawings.

[0057] Please refer to Figures 1-8 As shown, in this embodiment, the battery cell 100 includes: a housing 1, an electrode assembly 2, and a first electrode terminal 3. The housing 1 has a receiving space 11 and includes a first wall 12. The electrode assembly 2 is disposed in the receiving space 11, and the first electrode terminal 3 is disposed on the first wall 12. The first electrode terminal 3 includes a first body portion 31 and a first extension portion 32. Along the first direction X, the first extension portion 32 protrudes from the first body portion 31. The first direction X is perpendicular to the thickness direction of the first wall 12. The first wall 12 is provided with a first through hole 121. Along the thickness direction of the first wall 12, the first through hole 121 penetrates the first wall 12 so that the first body portion 31 is electrically connected to the electrode assembly 2. Along the first direction X, the first extension portion 32 is disposed opposite to the center line of the first through hole 121.

[0058] Specifically, the battery cell 100 includes a housing 1, which has multiple housing walls. For ease of description, one of the housing walls is referred to as the first wall 12. The battery cell 100 also includes an electrode assembly 2, which is located within a receiving space 11 enclosed by the multiple housing walls.

[0059] Electrode assembly 2 includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of the battery cell 100, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, disposed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing active ions to pass through. Electrode assembly 2 can be constructed as a stacked and wound body formed by layering and winding the positive electrode, negative electrode, and separator; however, electrode assembly 2 is not limited to a wound type, and can also be a stacked type or other structural forms.

[0060] In some embodiments, the outer casing 1 can be a sealed structure or a non-sealed structure. As an example, when the outer casing 1 is a non-sealed structure, it serves to protect the electrode assembly 2. A sealing bag is also included between the outer casing 1 and the electrode assembly 2, and the sealing bag is used to encapsulate the electrode assembly 2 and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film. As an example, the battery cell 100 can be a cylindrical battery cell 100, a prismatic battery cell 100, a pouch battery cell 100, or other shaped battery cells 100. Prismatic battery cells 100 include prismatic battery cells 100, blade-shaped battery cells 100, and multi-prismatic batteries, such as hexagonal prismatic batteries. For ease of explanation, this application uses a prismatic battery cell 100 as an example.

[0061] In some embodiments, such as Figure 3 As shown, the housing 1 includes multiple housing walls, a portion of which encloses a space with an opening. This opening can be closed by another housing wall (e.g., the first wall 12) to form a receiving space 11 for accommodating the electrode assembly 2 and substances such as electrolytes. The housing 1 may have one or more openings. The housing wall (e.g., the first wall 12) that closes the opening may also be configured as a top cover.

[0062] like Figure 1 and Figure 2 As shown, the battery cell 100 also includes a first electrode terminal 3, which is disposed on the first wall 12. The first electrode terminal 3 is connected to the electrode assembly 2 to conduct current into or out of the electrode assembly 2. The first electrode terminal 3 includes a first body portion 31 and a first extension portion 32 connected to each other. Optionally, the first body portion 31 and the first extension portion 32 can be an integral structure or a separate structure. When the first body portion 31 and the first extension portion 32 are separate structures, the first body portion 31 and the first extension portion 32 can be directly connected or indirectly connected. The materials of the first body portion 31 and the first extension portion 32 can be the same or different, but both are conductive metal materials.

[0063] Furthermore, along the first direction X, the first extension 32 protrudes from the first body portion 31, wherein the first direction X is perpendicular to the thickness direction of the first wall 12, the first wall 12 is provided with a first through hole 121, the first through hole 121 penetrates the first wall 12 along the thickness direction of the first wall 12, and a portion of the first body portion 31 passes through the first through hole 121 to be electrically connected to the electrode assembly 2. It can be understood that the first body portion 31 can be directly connected to the electrode tab, or it can be indirectly connected to the electrode tab through an adapter.

[0064] Since the first body portion 31 is electrically connected to the electrode assembly 2, when the first body portion 31 transmits current, heat is mainly generated in the first body portion 31. However, this application provides a first extension portion 32 connected to the first body portion 31. Therefore, some of the heat from the first body portion 31 can be dissipated outward through the first extension portion 32. In other words, the first extension portion 32 is equivalent to expanding the heat dissipation area of ​​the first electrode terminal 3, which is beneficial to improving the heat dissipation performance of the first electrode terminal 3, that is, it is beneficial to enhance the heat dissipation capacity of the battery cell 100, thereby reducing the temperature of the battery cell 100 and improving the performance of the battery cell 100.

[0065] Meanwhile, in some embodiments, the first extension 32 is arranged opposite to the center line of the first through hole 121 along the first direction X. If the first extension 32 is electrically connected to the busbar 200, when the current is transmitted from the part of the first body 31 that extends into the first through hole 121 to the first extension 32, it can be ensured that the current flows to the first extension 32 along the shortest straight distance. This is beneficial to reduce the length of the current flow path, so while satisfying the heat dissipation performance, it is also beneficial to reduce the impact on current transmission.

[0066] In this embodiment, as Figure 4 As shown, along the second direction Y, the size of the first body part 31 is d1 mm, the size of the first extension part 32 is d2 mm, and the first direction X, the second direction Y and the thickness direction of the first wall 12 are perpendicular to each other, satisfying: d1 > d2.

[0067] Specifically, based on 100 battery cells... Figure 4 Taking the arrangement shown as an example, the second direction Y is the width direction of the battery cell 100. Along the second direction Y, the size of the first body portion 31 is d1 mm, and the size of the first extension portion 32 is d2 mm, satisfying d1 > d2. That is, the size of the first body portion 31 along the second direction Y is larger than the size of the first extension portion 32 along the second direction Y. This is because the first body portion 31 requires more heat dissipation; therefore, increasing the size of the first body portion 31 is beneficial to improving the heat dissipation performance of the first electrode terminal 3. Simultaneously, if the first extension portion 32 is electrically connected to the busbar 200, since the first extension portion 32 needs to transmit current along the first direction X, setting the size of the first extension portion 32 along the second direction Y to a smaller size is beneficial to improving the current-carrying capacity of the first extension portion 32, thereby ensuring the current-carrying performance of the first extension portion 32 and the busbar 200.

[0068] In this embodiment, as Figure 4As shown, the dimension of the first extension 32 in the first direction X is greater than the dimension of the first extension 32 in the second direction Y. The first direction X is the length direction of the battery cell 100. If the first extension 32 is electrically connected to the busbar 200, current is transmitted along the first direction X from the portion of the first body 31 that extends into the first through hole 121 to the first extension 32. By setting the dimension of the first extension 32 in the first direction X to be greater than its dimension in the second direction Y, the length of the first extension 32 in the first direction X is increased and the width of the first extension 32 in the second direction Y is reduced. This configuration further improves the current-carrying capacity of the first extension 32, thereby further improving the current-carrying performance of the first extension 32 and the busbar 200.

[0069] In this embodiment, the size d1 mm of the first body portion 31 satisfies: 20 mm ≤ d1 mm ≤ 50 mm, and the size d2 mm of the first extension portion 32 satisfies: 13 mm ≤ d2 mm ≤ 40 mm. It can be understood that the size d1 mm of the first body portion 31 can be 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, etc.; and the size d2 mm of the first extension portion 32 can be 13 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, etc.

[0070] In this embodiment, as Figure 5 As shown, the first wall 12 has a first center line 125 along the second direction Y. The two side walls of the first wall 12 are equidistant from the first center line 125. The first direction X, the second direction Y and the thickness direction of the first wall 12 are perpendicular to each other. The distance between the center line of the first through hole 121 and the first center line 125 is d3 mm, which satisfies: 0≤d3 mm≤3mm.

[0071] Specifically, the first centerline 125 is located in the middle of the first wall 12 along the second direction Y. The distance between the centerline of the first through hole 121 and the first centerline 125 is d3, satisfying 0 ≤ d3 mm ≤ 3 mm. That is, the centerline of the first through hole 121 is set near the first centerline 125. For example, the distance between the centerline of the first through hole 121 and the first centerline 125 can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2 ... With the dimensions of 0.8mm, 2.9mm, and 3.0mm, the center line of the first through hole 121 is positioned near the first center line 125. This arrangement allows the entire first body portion 31 to be located near the first center line 125, thus providing more design dimensions for the first body portion 31 along the second direction Y, which is beneficial for improving the heat dissipation of the first electrode terminal 3. At the same time, the entire first extension portion 32 is also located near the first center line 125. If the first extension portion 32 is electrically connected to the busbar 200, since the first extension portion 32 needs to transmit current along the first direction X, a smaller dimension can be provided for the first extension portion 32 along the second direction Y, which is beneficial for improving the current carrying capacity of the first electrode terminal 3.

[0072] In this embodiment, as Figure 5 As shown, the minimum distance between the first electrode terminal 3 and the outer periphery of the first wall 12 is d4 mm, which satisfies: 8mm≤d4≤15mm.

[0073] In other words, it is necessary to reasonably control the minimum distance between the first electrode terminal 3 and the outer periphery of the first wall 12. If d4 is too large, the size of the first electrode terminal 3 will be too small, which is not conducive to the overcurrent and heat dissipation of the first electrode terminal 3. If d4 is too small, the first electrode terminal 3 will be too close to the outer periphery of the first wall 12, which increases the risk of short circuit and affects the safety performance of the battery cell 100. Based on this, this application sets the minimum distance between the first electrode terminal 3 and the outer periphery of the first wall 12 in the range of 8mm-15mm to prevent the minimum distance between the first electrode terminal 3 and the outer periphery of the first wall 12 from being too large or too small, so as to improve the safety performance of the battery cell 100 while ensuring the overcurrent and heat dissipation performance of the first electrode terminal 3. Optionally, the minimum distance between the first electrode terminal 3 and the outer periphery of the first wall 12 can be 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, or 15mm.

[0074] In this embodiment, as Figure 5 As shown, the battery cell 100 also includes a second electrode terminal 4. The first wall 12 is provided with a second through hole 122 so that the second electrode terminal 4 is electrically connected to the electrode assembly 2. The first wall 12 has a second center line 126 along the first direction X. The distance between the two side walls of the first wall 12 and the second center line 126 is the same. The first electrode terminal 3 and the second electrode terminal 4 are symmetrical about the second center line 126.

[0075] Specifically, the shapes of the first electrode terminal 3 and the second electrode terminal 4 can be the same or different. Along the first direction X, the first electrode terminal 3 and the second electrode terminal 4 are located on the left and right sides of the first wall 12 and are symmetrically arranged relative to the second center line 126. This symmetrical layout ensures that the path length of the current from the active material inside the battery cell 100 to the external terminal is approximately equal. This leads to a more uniform distribution of current in the current collector and electrode. The uniformity of current distribution directly brings two core benefits: First, it avoids "hot spots" caused by excessively high local current density, significantly improving the battery cell 100's ability to withstand high current charging and discharging (i.e., overcurrent capability). At the same time, the shortened average path also reduces the overall ohmic internal resistance. Second, uniform current means that the heat generation sources inside the battery are also uniform, avoiding dangerous local overheating. Therefore, this symmetrical design is not only an aesthetic choice but also a key technology that optimizes the electro-thermal-structural coupling relationship to simultaneously achieve high overcurrent capability and excellent heat dissipation performance.

[0076] It should be noted that the arrangement of the first electrode terminal 3 and the second electrode terminal 4 can increase the contact area between the electrode terminals and the air, which is beneficial to improving the heat dissipation capacity of the electrode terminals and thus improving the performance of the battery cell 100.

[0077] In this embodiment, as Figures 1-8 As shown, the second electrode terminal 4 includes a second body portion 41 and a second extension portion 42. Along the first direction X, the second extension portion 42 protrudes from the second body portion 41 and extends toward the first electrode terminal 3.

[0078] Specifically, the first electrode terminal 3 and the second electrode terminal 4 have the same shape. The first electrode terminal 3 has a first extension 32 protruding along the first direction X, and the second electrode terminal 4 has a second extension 42 protruding along the first direction X. The second extension 42 extends toward the first electrode terminal 3 along the first direction X. With this arrangement, some of the heat from the second body portion 41 can be dissipated outward through the second extension 42. In other words, the second extension 42 effectively expands the heat dissipation area of ​​the second electrode terminal 4, which is beneficial to improving the heat dissipation performance of the second electrode terminal 4. This is beneficial to enhancing the heat dissipation capacity of the battery cell 100, thereby reducing the temperature of the battery cell 100 and improving the performance of the battery cell 100.

[0079] Meanwhile, in some embodiments, the second extension 42 is arranged opposite to the center line of the second through hole 122 along the first direction X. If the second extension 42 is electrically connected to the busbar 200, when the current is transmitted from the part of the second body part 41 that extends into the second through hole 122 to the second extension 42, it can be ensured that the current flows to the second extension 42 along the shortest straight distance. This is beneficial to reduce the current flow path length, so while satisfying the heat dissipation performance, it is also beneficial to reduce the impact on current transmission.

[0080] In this embodiment, as Figure 6 As shown, along the first direction X, the distance between the first extension 32 and the second extension 42 is d5 mm, satisfying: 50mm ≤ d5 mm ≤ 250mm. That is, the distance d5 mm between the first extension 32 and the second extension 42 along the first direction X needs to be reasonably controlled. If d5 mm is too large, the dimensions of the first extension 32 and the second extension 42 along the first direction X will be too small, thus not significantly improving the heat dissipation performance of the first electrode terminal 3 and the second electrode terminal 4. If d5 mm is too small, the first extension 32 and the second extension 42 will be too close, increasing the risk of short circuits and affecting the safety performance of the battery cell 100. Based on this, this application sets the distance d5 mm between the first extension 32 and the second extension 42 within the range of 50mm-250mm to prevent d5 from being too large or too small. While ensuring the heat dissipation performance of the first electrode terminal 3 and the second electrode terminal 4, it also ensures a safe insulation distance between the first electrode terminal 3 and the second electrode terminal 4, thereby improving the safety performance of the battery cell 100. Optionally, d5 can be 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 150mm, 200mm, or 250mm.

[0081] In this embodiment, the first wall 12 is provided with an injection hole 123. The injection hole 123 penetrates the first wall 12 along the thickness direction of the first wall 12. Along the first direction X, the distance between the injection hole 123 and the first extension 32 is less than or equal to the distance between the injection hole 123 and the second extension 42. The distance between the injection hole 123 and the first extension 32 is d6 mm, which satisfies: 15mm≤d6mm≤30mm.

[0082] Specifically, the injection hole 123 of the first wall 12 is used to inject electrolyte into the battery cell 100. Along the thickness direction of the first wall 12, the injection hole 123 penetrates the first wall 12. The distance between the injection hole 123 and the first extension 32 is less than or equal to the distance between the injection hole 123 and the second extension 42. That is to say, the injection hole 123 can be located between the first extension 32 and the second extension 42, or it can be closer to the first extension 32 relative to the second extension 42 along the first direction X. The distance between the injection hole 123 and the first extension 32 is d6 mm. It can be understood that d6 mm is the shortest interval distance between the injection hole 123 and the first extension 32.

[0083] It is necessary to reasonably control the shortest interval distance between the injection hole 123 and the first extension 32. If d6 mm is too large, the dimension of the first extension 32 along the first direction X will be too small, which is not conducive to the flow and heat dissipation of the first extension 32. If d6 mm is too small, the first extension 32 will be too close to the injection hole 123, which will easily lead to stress concentration in the structural attachments of the injection hole 123, thereby reducing the strength of the first wall 12. Based on this, this application sets the shortest interval distance d6 between the injection hole 123 and the first extension 32 in the range of 15mm-30mm to prevent the shortest interval distance between the injection hole 123 and the first extension 32 from being too large or too small. While ensuring the strength of the first wall 12, it improves the flow and heat dissipation performance of the first electrode terminal 3. Optionally, d6 mm can be 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 25mm, or 30mm.

[0084] In this embodiment, the first wall 12 is provided with a pressure relief mechanism 124. The pressure relief mechanism 124 is used to relieve pressure when the internal pressure of the battery cell 100 reaches a certain level. Along the first direction X, the distance between the pressure relief mechanism 124 and the first extension 32 is less than or equal to the distance between the pressure relief mechanism 124 and the second extension 42. The distance between the pressure relief mechanism 124 and the first extension 32 is d7mm, which satisfies the condition: 20mm≤d7mm≤100mm.

[0085] Specifically, the pressure relief mechanism 124 of the first wall 12 is used for pressure relief and explosion prevention. Along the first direction X, the distance between the pressure relief mechanism 124 and the first extension 32 is less than or equal to the distance between the pressure relief mechanism 124 and the second extension 42. That is to say, the pressure relief mechanism 124 can be located between the first extension 32 and the second extension 42, or it can be located closer to the first extension 32 relative to the second extension 42 along the first direction X. The distance between the pressure relief mechanism 124 and the first extension 32 is d7. It can be understood that d7 is the shortest interval distance between the pressure relief mechanism 124 and the first extension 32.

[0086] It is necessary to reasonably control the shortest interval distance between the pressure relief mechanism 124 and the first extension 32. If d7 is too large, the dimension of the first extension 32 along the first direction X will be too small, which is not conducive to the overcurrent and heat dissipation of the first extension 32. If d7 mm is too small, the first extension 32 will be too close to the pressure relief mechanism 124, which may easily lead to stress concentration in the structural accessories of the pressure relief mechanism 124, thereby causing the pressure relief mechanism 124 to fail. Based on this, this application sets the shortest interval distance between the pressure relief mechanism 124 and the first extension 32 in the range of 20mm-100mm to prevent the shortest interval distance between the pressure relief mechanism 124 and the first extension 32 from being too large or too small. While ensuring the normal operation of the pressure relief mechanism 124, it also improves the overcurrent and heat dissipation performance of the first electrode terminal 3. Optionally, d7 mm can be 20mm, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, or 100mm.

[0087] In this embodiment, as Figures 1-8 As shown, the first direction X is parallel to the length direction of the first wall 12. That is, the first direction X is the length direction of the first wall 12. This arrangement makes the first electrode terminal 3 and the second electrode terminal 4 symmetrically arranged along the length direction of the first wall 12, thereby providing sufficient installation space for the first electrode terminal 3 and the second electrode terminal 4 and further reducing the risk of short circuit.

[0088] In this embodiment, as Figure 3 As shown, the battery cell 100 also includes a first insulating member 5. Along the thickness direction of the first wall 12, the first insulating member 5 is disposed on the side of the first wall 12 away from the electrode assembly 2, and at least a portion of the first electrode terminal 3 is disposed on the side of the first insulating member 5 away from the electrode assembly 2. Specifically, the first insulating member 5 is disposed on the outer side of the first wall 12, and the first insulating member 5 is located between the first wall 12 and at least a portion of the first electrode terminal 3. For example, the first insulating member 5 can be constructed as a rubber part, a plastic part, etc. With this arrangement, by providing the first insulating member 5 between the first wall 12 and the first electrode terminal 3, insulation between the first wall 12 and the first electrode terminal 3 can be achieved, avoiding short circuit caused by conduction between the first wall 12 and the first electrode terminal 3, which is beneficial to improving the safety performance of the battery cell 100.

[0089] In this embodiment, a groove is provided on the side of the first wall 12 opposite to the electrode assembly 2 along the thickness direction, and at least a portion of the first insulating member 5 is disposed in the groove. That is, the outer side wall of the first wall 12 has a groove for installing the first insulating member 5, such that at least a portion of the first insulating member 5 is disposed in the groove. For example, the first insulating adhesive can be completely installed in the groove or partially disposed in the groove. By providing the groove, the positioning and installation of the first insulating member 5 is facilitated, thereby improving the assembly efficiency of the battery cell 100.

[0090] In this embodiment, as Figure 3 As shown, along the thickness direction of the first wall 12, the projection of the first through hole 121 falls within the projection of the first electrode terminal 3. That is, the size of the first electrode terminal 3 is larger than the size of the first through hole 121, ensuring that the first electrode terminal 3 completely covers the first through hole 121. This arrangement allows the first electrode terminal 3 to seal the first through hole 121, preventing impurities from entering the battery cell 100 and affecting its performance. Simultaneously, a portion of the first electrode terminal 3 is electrically connected to the electrode assembly 2 through the first through hole 121, ensuring the heat dissipation performance of the first electrode terminal 3.

[0091] It is understandable that the projection of the first through hole 121 falls within the projection of the second electrode terminal 4, which will not be elaborated further here.

[0092] In this embodiment, as Figure 3 As shown, along the thickness direction of the first wall 12, the first body portion 31 is located on the side of the first through hole 121 away from the electrode assembly 2. That is, it is mounted with the battery cell 100. Figure 3 Taking the placement direction shown as an example, at least a portion of the first body part 31 is located above the first through hole 121. This arrangement facilitates the connection of the first electrode terminal 3 to the external busbar 200, thereby improving the assembly efficiency of the battery cell 100 and the busbar 200.

[0093] In this embodiment, as Figure 3 As shown, the first body part 31 has a first connecting section 311, which is disposed in the first through hole 121.

[0094] Specifically, the first connecting section 311 of the first body part 31 is completely located within the first through hole 121, facilitating an electrical connection with the electrode assembly 2 inside the battery. Simultaneously, placing the first connecting section 311 within the first through hole 121 makes the connection between the first body part 31 and the first wall 12 more stable. The first through hole 121 provides positioning and support for the first electrode terminal 3, restricting its movement and shaking, reducing the possibility of loosening or detachment between the first electrode terminal 3 and the first wall 12 due to battery vibration or external impact, thus improving the overall stability and reliability of the battery structure.

[0095] Furthermore, the arrangement of the first connecting segment 311 within the first through hole 121 facilitates the battery's sealing design. Typically, a seal is installed at the first through hole 121, and the first connecting segment 311, located within it, works in conjunction with the seal to achieve a better sealing effect. The seal can form a good seal around the first connecting segment 311, preventing external air and moisture from entering the battery cell 100, improving the stability of the internal environment of the battery cell 100, and extending the service life of the battery cell 100.

[0096] It is understandable that the second electrode terminal 4 can adopt a similar design, with the third connecting section 411 of the second electrode terminal 4 disposed in the second through hole 122, which will not be described in detail here.

[0097] In this embodiment, as Figure 3 As shown, the first body part 31 also has a second connecting section 312, which is connected to the end of the first connecting section 311 near the electrode assembly 2, and the second connecting section 312 is located in the receiving space 11.

[0098] Specifically, the second connecting segment 312 extends into the first receiving space 11, allowing it to directly connect to the electrode assembly 2. This ensures the shortest current transmission path and lowest resistance between the first electrode terminal 3 and the electrode assembly 2, thereby improving the battery's charging and discharging efficiency, reducing energy loss, and optimizing the internal structural layout of the battery. It can be rationally designed and arranged according to the shape, size, and position of the electrode assembly 2, making more efficient use of space among the internal components of the battery and improving the overall compactness and stability of the battery.

[0099] It is understandable that the second electrode terminal 4 can adopt a similar design, with the fourth connecting segment 412 of the second electrode terminal 4 connected to the end of the third connecting segment 411 near the electrode assembly 2. The fourth connecting segment 412 is located in the receiving space 11, which will not be described in detail here.

[0100] In this embodiment, the battery pack 1000 includes the battery cell 100 in the first aspect embodiment of this application.

[0101] According to the battery pack 1000 of the present application embodiment, by providing the above-mentioned battery cell 100, the first electrode terminal 3 in the battery cell 100 includes a first body portion 31 and a first extension portion 32. The first body portion 31 is used for electrical connection with the electrode assembly 2, so heat is mainly generated in the first body portion 31. In this application, the first extension portion 32 protrudes from the first body portion 31 along the first direction X. With this arrangement, some of the heat of the first body portion 31 can be dissipated outward through the first extension portion 32. The first extension portion 32 is equivalent to expanding the heat dissipation area of ​​the first electrode terminal 3, which is beneficial to improving the heat dissipation performance of the first electrode terminal 3. At the same time, the first extension portion 32 is arranged opposite to the center line of the first through hole 121 along the first direction X. This can ensure that the current flows from the electrode assembly 2 to the first extension portion 32 along the shortest straight distance, reducing the flow path. Therefore, while satisfying the heat dissipation performance, it is also beneficial to reduce the impact on current transmission.

[0102] like Figure 9 As shown, in this embodiment, the battery pack 1000 further includes a first busbar 200, which is electrically connected to the first extension 32 of each battery cell 100. That is, the battery pack 1000 includes a plurality of battery cells 100, and the first extensions 32 of each battery cell 100 are interconnected via the first busbar 200. For example, such as... Figure 9 As shown, the first extension 32 in the two battery cells 100 are electrically connected through the first busbar 200. This ensures the overall heat dissipation performance while reducing the current flow path in different battery cells 100, thereby improving the heat dissipation performance and ensuring the current transmission performance of the battery pack 1000.

[0103] like Figure 9 As shown, in this embodiment, the battery pack 1000 further includes a second busbar 300, which is electrically connected to the second body portion 41 of at least two battery cells 100. Specifically, the battery pack 1000 may include multiple rows of battery cells 100 arranged in parallel. The last battery cell 100 in each row can be electrically connected to the corresponding second body portion 41 of the last battery cell 100 in other rows through its corresponding second body portion 41. This facilitates the series arrangement of multiple rows of battery cells 100. At the same time, the second extension portion 42 can be used for heat dissipation. Furthermore, the second busbar 300 connects different second body portions 41, which can further reduce the current flow path between different battery cells 100. Thus, the battery pack 1000 improves both heat dissipation performance and current transmission performance.

[0104] In this embodiment, the electrical equipment includes the battery cell 100 in the first aspect embodiment of this application or the battery pack 1000 in the first aspect embodiment of this application.

[0105] According to the embodiments of this application, the electrical device is provided with the above-mentioned battery cell 100 or battery pack 1000. The first electrode terminal 3 in the battery cell 100 includes a first body portion 31 and a first extension portion 32. The first body portion 31 is used for electrical connection with the electrode assembly 2. Therefore, heat is mainly generated in the first body portion 31. In this application, the first extension portion 32 protrudes from the first body portion 31 along the first direction X. With this arrangement, some of the heat of the first body portion 31 can be dissipated outward through the first extension portion 32. The first extension portion 32 is equivalent to expanding the heat dissipation area of ​​the first electrode terminal 3, which is beneficial to improving the heat dissipation performance of the first electrode terminal 3. At the same time, the first extension portion 32 is arranged opposite to the center line of the first through hole 121 along the first direction X. This can ensure that the current flows from the electrode assembly 2 to the first extension portion 32 along the shortest straight distance, reducing the flow path. Therefore, while satisfying the heat dissipation performance, it is also beneficial to reduce the impact on current transmission.

[0106] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0107] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0108] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0109] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that, include: An outer casing having a receiving space, the outer casing including a first wall; Electrode assembly, disposed within the receiving space; A first electrode terminal is disposed on the first wall. The first electrode terminal includes a first body portion and a first extension portion. Along a first direction, the first extension portion protrudes from the first body portion. The first direction is perpendicular to the thickness direction of the first wall. The first wall is provided with a first through hole, which penetrates the first wall along the thickness direction to enable the first body part to be electrically connected to the electrode assembly. Along the first direction, the first extension part is disposed opposite to the center line of the first through hole.

2. The battery cell according to claim 1, characterized in that, Along the second direction, the size of the first body portion is d1 mm, the size of the first extension portion is d2 mm, and the first direction, the second direction and the thickness direction of the first wall are perpendicular to each other, satisfying: d1 > d2.

3. The battery cell according to claim 2, characterized in that, The dimension of the first extension in the first direction is greater than the dimension of the first extension in the second direction.

4. The battery cell according to claim 1, characterized in that, The first wall has a first center line along a second direction, and the two side walls of the first wall are equidistant from the first center line. The first direction, the second direction, and the thickness direction of the first wall are perpendicular to each other. The distance between the centerline of the first through hole and the first centerline is d3 mm, which satisfies: 0≤d3 mm≤3mm.

5. The battery cell according to claim 1, characterized in that, The minimum distance between the first electrode terminal and the outer periphery of the first wall is d4 mm, which satisfies: 8mm≤d4≤15mm.

6. The battery cell according to claim 1, characterized in that, The battery cell further includes a second electrode terminal, and the first wall is provided with a second through hole to allow the second electrode terminal to be electrically connected to the electrode assembly. The first wall has a second center line. Along the first direction, the two side walls of the first wall are equidistant from the second center line. The first electrode terminal and the second electrode terminal are symmetrical about the second center line.

7. The battery cell according to claim 6, characterized in that, The second electrode terminal includes a second body portion and a second extension portion. Along a first direction, the second extension portion protrudes from the second body portion and extends toward the first electrode terminal.

8. The battery cell according to claim 7, characterized in that, Along the first direction, the distance between the first extension and the second extension is d5 mm, satisfying: 50mm≤d5mm≤250mm.

9. The battery cell according to claim 6, characterized in that, The first wall is provided with an injection hole. The injection hole penetrates the first wall along the thickness direction. Along the first direction, the distance between the injection hole and the first extension is less than or equal to the distance between the injection hole and the second extension. The distance between the injection hole and the first extension is d6 mm, which satisfies: 15mm≤d6mm≤30mm.

10. The battery cell according to claim 1, characterized in that, The first wall is provided with a pressure relief mechanism, which is used to relieve pressure when the internal pressure of the battery cell reaches a certain level. Along the first direction, the distance between the pressure relief mechanism and the first extension is equal to the distance between the pressure relief mechanism and the second extension. The distance between the pressure relief mechanism and the first extension is d7 mm, which satisfies the condition: 20mm≤d7mm≤100mm.

11. The battery cell according to claim 1, characterized in that, The first direction is parallel to the length direction of the first wall.

12. The battery cell according to claim 1, characterized in that, The battery cell further includes a first insulating member, which is disposed on the side of the first wall away from the electrode assembly along the thickness direction of the first wall, and at least a portion of the first electrode terminal is disposed on the side of the first insulating member away from the electrode assembly.

13. The battery cell according to claim 12, characterized in that, Along the thickness direction of the first wall, a groove is provided on the side of the first wall opposite to the electrode assembly, and at least a portion of the first insulating member is disposed in the groove.

14. The battery cell according to claim 1, characterized in that, Along the thickness direction of the first wall, the projection of the first through hole falls within the projection of the first electrode terminal.

15. The battery cell according to claim 1, characterized in that, Along the thickness direction of the first wall, the first body portion is located on the side of the first through hole away from the electrode assembly.

16. The battery cell according to claim 1, characterized in that, The first body portion has a first connecting section, which is disposed in the first through hole.

17. The battery cell according to claim 16, characterized in that, The first body portion also has a second connecting segment, which is connected to one end of the first connecting segment near the electrode assembly, and the second connecting segment is located in the receiving space.

18. A battery pack, characterized in that, Includes the battery cells as described in claims 1-17.

19. The battery pack according to claim 18, characterized in that, The battery pack further includes a first bus, which is electrically connected to the first extension of each of the battery cells.

20. The battery pack according to claim 18, characterized in that, The battery pack further includes a second bus, which is electrically connected to the second body portion of at least two of the battery cells.

21. An electrical appliance, characterized in that, It includes the battery cell according to any one of claims 1-17 or the battery pack according to any one of claims 18-20.

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