Connecting piece, battery monomer, battery and electric device

Abstract

The invention discloses a connecting piece, a battery monomer, a battery and a power utilization device, and belongs to the technical field of batteries. The connecting piece is applied to the single battery and connected between a tab and a pole, the connecting piece comprises a first section, a second section and a third section, the first end of the second section is connected with the first section, the second end of the second section is connected with the third section, and the width of the first section and the width of the third section are both larger than the width of the second section. According to the technical scheme, the connecting piece is designed to be of the three-section I-shaped structure, so that the connecting piece can obtain higher overcurrent capacity in the weak link of the switching part at the two ends, the safety risks of overhigh local temperature and the like caused by insufficient overcurrent capacity are reduced, meanwhile, the contact area between the connecting piece and the tab and the contact area between the connecting piece and the post terminal can be increased, and the service life of the connecting piece is prolonged. Therefore, the available welding area is increased.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and in particular relates to a connecting piece, a battery cell, a battery and an electrical device. Background Art

[0002] The tabs at the connection between the core and the cover are weak points for current flow. Insufficient current flow capacity will result in high tab temperatures when large currents pass through, limiting the battery's fast charging and high power performance. In related technologies, thicker current collectors are usually used to improve current flow capacity, but thickening the current collector will affect the cell capacity and weight. At the same time, the tabs are exposed for a long time, which can easily cause tab folding and insertion during transportation and assembly, leading to shell short circuits, which seriously affects production yields and leaves room for improvement. Summary of the invention

[0003] The present application aims to at least solve the technical problems of insufficient current carrying capacity of the battery cell and long exposed size of the tab in the related art. To this end, the present application proposes a connecting piece, a battery cell, a battery and an electrical device, which can improve the current carrying capacity of the battery cell and increase the production yield, and reduce safety risks.

[0004] In a first aspect, the present application provides a connecting sheet, which is applied to a battery cell and connected between a pole ear and a pole, and includes:

[0005] Paragraph 1;

[0006] a second segment, wherein a first end of the second segment is connected to the first segment, and a width of the second segment is smaller than a width of the first segment;

[0007] The third section is connected to the second end of the second section, and the width of the third section is greater than the width of the second section.

[0008] By designing the connecting piece as a three-section "I"-shaped structure, the connecting piece can obtain a higher current-carrying capacity, thereby reducing safety risks such as excessive local temperature caused by insufficient current-carrying capacity.

[0009] According to one embodiment of the present application, the thickness of the second segment is greater than the thickness of the first segment and the thickness of the third segment.

[0010] The design that the thickness of the second section of the connecting sheet is greater than the thickness of the first section and the thickness of the third section can enable the connecting sheet to exert the best performance and safety in the battery cell.

[0011] According to one embodiment of the present application, the second section includes a first connecting section, a main section and a second connecting section, the first connecting section is connected to the first section, the second connecting section is connected to the third section, and the thickness of the first connecting section and the second connecting section gradually decreases in a direction away from the main section.

[0012] The second section of the connecting piece includes the first connecting section, the main section and the second connecting section, and the thickness of the first connecting section and the second connecting section is gradually reduced in the direction away from the main section, which can achieve a smooth transition of the connecting piece and optimize the current distribution in the connecting piece.

[0013] According to an embodiment of the present application, a chamfer is provided at a connection between the first connecting section and the first section;

[0014] and / or,

[0015] A chamfer is provided at a connection between the second connection section and the third section.

[0016] Providing chamfers at the connection between the first connecting section and the first section and at the connection between the second connecting section and the third section can reduce stress concentration and help improve product reliability and performance.

[0017] According to an embodiment of the present application, a difference in flow area between any two of the first segment, the second segment, and the third segment is less than 5%.

[0018] The design that the difference between any two flow areas of the first section, the second section and the third section is less than 5% helps to improve the performance and quality of the connecting sheet in the battery cell.

[0019] According to one embodiment of the present application, the height of the second segment is greater than the height of the first segment and the height of the third segment.

[0020] By properly designing the height and shape of the second section, a higher current capacity can be obtained, thereby improving the efficiency and service life of the battery.

[0021] In a second aspect, the present application provides a battery cell, comprising:

[0022] a shell, forming a cavity;

[0023] A cover body, used for sealing the cavity, the cover body being provided with a pole;

[0024] A pole core is installed in the cavity, and the pole core includes a current collector and a pole ear;

[0025] As in any one of the above-mentioned connecting pieces, the connecting piece is installed in the cavity, the first section of the connecting piece is electrically connected to the pole, and the third section of the connecting piece is electrically connected to the pole ear.

[0026] The shell and the cover together protect the internal components of the battery from interference and damage from the external environment, while providing necessary mechanical support and heat dissipation channels to achieve efficient and safe operation of the battery.

[0027] According to an embodiment of the present application, the pole includes a pole body and a lead-out plate, and the first section of the connecting plate is electrically connected to the lead-out plate.

[0028] The synergistic effect of the pole and the connecting piece helps to smoothly conduct the current inside the battery cell, thereby improving the performance and efficiency of the battery.

[0029] According to an embodiment of the present application, the width of the first section of the connecting piece is the same as the width of the lead-out piece, and the first section is fully welded to the lead-out piece;

[0030] and / or,

[0031] The width of the third section of the connecting sheet is the same as the width of the pole lug, and the third section is fully welded to the pole lug.

[0032] The first section of the connecting piece and the lead-out piece, as well as the third section and the pole lug, are fully welded to each other, which can significantly improve the smooth conduction performance of the internal current of the battery cell.

[0033] In a third aspect, the present application provides a battery, comprising:

[0034] A plurality of battery cells as described above.

[0035] By combining a plurality of the battery cells, the total energy density of the battery can be increased, which is helpful for the efficient transmission of electric energy.

[0036] In a fourth aspect, the present application provides an electrical device, comprising:

[0037] The battery as described above is used to provide electrical energy to the electrical device.

[0038] The electrical device integrates the battery as an energy source to drive its internal working mechanism or perform specific functions.

[0039] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0041] Figure 1 It is one of the structural schematic diagrams of a battery cell provided in an embodiment of the present application;

[0042] Figure 2 is a schematic structural diagram of a connecting piece of a battery cell provided in an embodiment of the present application;

[0043] Figure 3 This is the second structural schematic diagram of the battery cell provided in the embodiment of the present application.

[0044] Reference numerals:

[0045] Battery cell 1;

[0046] Connecting piece 10;

[0047] The first paragraph 110,

[0048] A second section 120, a first connecting section 121, a main section 122, and a second connecting section 123;

[0049] Paragraph 3, 130,

[0050] Shell 20, cavity 210;

[0051] Cover body 30;

[0052] Pole 40, lead piece 410;

[0053] A pole core 50, a current collector 510, and a pole ear 520;

[0054] The width of the first segment is W1, the width of the second segment is W2, and the width of the third segment is W3;

[0055] The length of the first segment is L1, the length of the second segment is L2, and the length of the third segment is L3;

[0056] The thickness of the first section is d1, the thickness of the second section is d2, and the thickness of the third section is d3. DETAILED DESCRIPTION

[0057] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0058] The present application aims to at least solve the technical problems of insufficient current carrying capacity of the battery cell and long exposed size of the tab in the related art. To this end, the present application proposes a connecting piece, a battery cell, a battery and an electrical device, which can improve the current carrying capacity of the battery cell and increase the production yield, and reduce safety risks.

[0059] Reference below Figure 1-Figure 3 A connection sheet 10 according to an embodiment of the present application is described.

[0060] like Figure 1 As shown, the connecting piece 10 is applied to the battery cell 1 and connected between the pole ear 520 and the pole 40. The connecting piece 10 includes: a first section 110, a second section 120 and a third section 130. The first end of the second section 120 is connected to the first section 110, and the width W1 of the first section 110 is greater than the width W2 of the second section 120. The second end of the second section 120 is connected to the third section 130, and the width W3 of the third section 130 is greater than the width W2 of the second section 120.

[0061] The connecting piece 10 is a bridge for current transmission inside the battery. It has good conductivity and helps to smoothly transmit the current. For example, in the battery cell 1, the current is transmitted from the negative electrode tab 520 to the external circuit or the next battery cell 1 through the connecting piece 10, and then returns to the positive electrode tab 520 to form a complete current loop. The connecting piece 10 can also play a role in mechanical connection, firmly connecting the various parts of the battery cell 1, such as the tab 520, the pole 40, etc., together, which helps to improve the integrity and stability of the battery structure.

[0062] In addition, a certain amount of heat will be generated during the charging and discharging process of the battery. The connecting piece 10, as a part of the battery, can also play a certain role in heat conduction, which helps to conduct heat from the inside of the battery to the outside and keep the battery temperature stable. The design of the connecting piece 10 can also consider the compatibility with other parts of the battery cell 1. For example, the shape, size and material of the connecting piece 10 are matched with the components such as the ear 520 and the pole 40 of the battery cell 1, which helps to improve the reliability and stability of the connection.

[0063] The connecting piece 10 is usually made of a metal material with good electrical conductivity, such as copper, aluminum or copper alloy. In practical applications, the size, material and structure of the connecting piece 10 can also be optimized according to the specific needs of the battery and the working environment. For example, in application scenarios that require higher current conduction efficiency, the width W1 of the first section 110 and the width W3 of the third section 130 can be appropriately increased. In application scenarios that require higher mechanical strength, a stronger material can be selected or the overall thickness of the connecting piece 10 can be increased. Through reasonable structural design and material selection, the connecting piece 10 can perform at its best in the battery cell 1.

[0064] like Figure 2 As shown in the figure, in the technical solution of the present application, the connecting piece 10 is composed of three parts. Among them, the second section 120 serves as an intermediate connecting part, with its first end connected to the first section 110 and its second end connected to the third section 130. The width W1 of the first section 110, the width W2 of the second section 120, and the width W3 of the third section 130 satisfy: W2 < W1, W2 < W3, that is, the connecting piece 10 has an "I" - shaped structure. The first section 110 and the third section 130 can provide a larger contact area to enhance the current conduction efficiency and increase mechanical stability.

[0065] In addition, as Figure 3 shown, the first section 110 of the connecting piece 10 is connected to the pole column 40, and the third section 130 of the connecting piece 10 is connected to the tab 520. In this structure, the second section 120 is not restricted by the connecting structure. The thickness d1 of the first section 110, the thickness d2 of the second section 120, and the thickness d3 of the third section 130 can satisfy: d1 < d2, d3 < d2, so as to balance the over - current capacity and the welding effect. At the same time, the width W1 of the first section 110 and the width W3 of the third section 130 are both greater than the width W2 of the second section 120, so that the over - current capacity of the whole connecting piece 10 is evenly distributed. At the same time, the middle position of the connecting piece 10 can be connected in a soft connection manner, bent and then installed on the battery cell 1 to improve the space utilization rate.

[0066] The tab 520 at the connection between the electrode core 50 and the cover 30 is a weak point for over - current. Insufficient over - current capacity will cause the temperature of the tab 520 to be relatively high when passing a large current, restricting the fast charging and high - power performance of the battery. In related technologies, usually a thicker current collector 510 is used to improve the over - current capacity. However, the thickening of the current collector 510 will affect the cell capacity and weight. At the same time, the exposed size of the tab 520 is relatively long, and problems such as the folding and internal insertion of the tab 520 are likely to occur during the transportation and assembly process, resulting in the problem of short - circuiting with the case, seriously affecting the production yield, and there is room for improvement.

[0067] The present application adds a connecting piece 10 between the tab 520 and the pole column 40 of the battery cell 1, which can reduce the exposed part of the tab 520, thereby reducing the risks such as the folding and internal insertion of the tab 520 during the transportation and assembly process, improving the production yield. At the same time, the connecting piece 10 is designed as a three - section "I" - shaped structure, and the width W1 of the first section 110 and the width W3 of the third section 130 are both greater than the width W2 of the second section 120, which can maximize the available welding area, thereby obtaining a higher over - current capacity.

[0068] According to the connecting piece 10 provided by the embodiments of the present application, by designing the connecting piece 10 into a three-section "I"-shaped structure, the connecting piece 10 can obtain higher current-carrying capacity at the weak links at both ends of the transfer joints, reduce safety risks such as excessive local temperature caused by insufficient current-carrying capacity, and at the same time increase the contact area between the connecting piece 10 and the tab 520 and the terminal 40, thereby increasing the available welding area.

[0069] In some embodiments, as Figure 3 shown, the thickness d2 of the second section 120 is greater than the thickness d1 of the first section 110 and the thickness d3 of the third section 130.

[0070] The thicknesses d1 of the first section 110, d2 of the second section 120, and d3 of the third section 130 satisfy: d1 < d2, d3 < d2, where the first section 110 and the third section 130 are connected to the tab 520 and the terminal 40, and are responsible for the current conduction between the connecting piece 10 and the tab 520 and the terminal 40 respectively. Increasing the thickness d2 of the second section 120 can affect the distribution of current inside the connecting piece 10, thereby increasing the current-carrying capacity of the connecting piece 10, and in some cases, can also reduce the local concentration of current in the connecting piece 10, thereby reducing resistance and heat generation, and improving the efficiency of the battery.

[0071] The thicker second section 120 can also provide higher mechanical strength and toughness to withstand mechanical stresses such as pressure, vibration, and shock during battery assembly, thereby improving the stability and durability of the entire battery structure. At the same time, the thinner first section 110 and third section 130 can improve the welding performance, thereby strengthening the connection strength between the first section 110 and the terminal 40 and between the third section 130 and the tab 520.

[0072] It can be understood that the design in which the thickness d2 of the second section 120 of the connecting piece 10 is greater than the thicknesses d1 of the first section 110 and d3 of the third section 130 can help the connecting piece 10 to exhibit the best performance and safety in the battery cell 1.

[0073] In some embodiments, as Figure 3 shown, the second section 120 includes a first connecting section 121, a main body section 122, and a second connecting section 123. The first connecting section 121 is connected to the first section 110, the second connecting section 123 is connected to the third section 130, and the thicknesses of both the first connecting section 121 and the second connecting section 123 gradually decrease in the direction away from the main body section 122.

[0074] The first connecting section 121 is connected between the main section 122 and the first section 110. The thickness of the main section 122 is greater than the thickness d1 of the first section 110. Along the direction away from the main section 122, the thickness of the first connecting section 121 gradually decreases from the thickness of the main section 122 to the thickness d1 of the first section 110. The second connecting section 123 is connected between the main section 122 and the third section 130. The thickness of the main section 122 is greater than the thickness d3 of the third section 130. The thickness of the second connecting section 123 gradually decreases from the thickness of the main section 122 to the thickness d3 of the third section 130.

[0075] The gradually decreasing thickness of the first connecting segment 121 and the second connecting segment 123 helps to achieve a smooth transition between the connecting piece 10 and other components, thereby reducing stress concentration and improving the reliability and durability of the connection. The gradually thinning connecting segments also help to distribute the current more evenly and reduce the local concentration of current in the connecting piece 10, thereby reducing the generation of resistance and heat and improving the efficiency and service life of the battery.

[0076] The thickness variation of the connecting segment can also enhance mechanical flexibility to better accommodate small deformations and displacements during battery assembly, helping to reduce stress and damage during assembly.

[0077] It can be understood that the second section 120 of the connecting piece 10 includes a first connecting section 121, a main section 122 and a second connecting section 123, and the thickness of the first connecting section 121 and the second connecting section 123 gradually decreases in the direction away from the main section 122, which can achieve a smooth transition of the connecting piece 10 and optimize the current distribution in the connecting piece 10.

[0078] In some embodiments, Figure 1 and 2 As shown, the connection between the first connecting section 121 and the first section 110 and the connection between the second connecting section 123 and the third section 130 may be chamfered separately or simultaneously.

[0079] The chamfer design can disperse the stress at the connection and help reduce stress concentration. Under dynamic conditions such as battery charging and discharging, vibration or impact, this stress dispersion effect can significantly improve the reliability and durability of the connection. The chamfer can also reduce the resistance of the connecting piece 10 during assembly, making the assembly process smoother. Especially in automated production lines, the chamfer design can significantly improve production efficiency and reduce production delays and cost increases caused by assembly errors.

[0080] During the contact between the connecting piece 10 and the pole lug 520, pole post 40 and other components, chamfering can also reduce the risk of friction and scratches, help protect the surface of the battery cell 1 and the connecting piece 10, and reduce performance degradation or safety hazards caused by scratches.

[0081] It can be understood that chamfers are provided at the joints of the first connecting section 121 and the first section 110 and at the joints of the second connecting section 123 and the third section 130, which can reduce the stress concentration phenomenon and help improve the reliability and performance of the product.

[0082] In some embodiments, the difference in the current-carrying areas between any two of the first section 110, the second section 120, and the third section 130 is less than 5%.

[0083] The current-carrying area of the first section 110 is the product of the width W1 and the thickness d1 of the first section 110, the current-carrying area of the second section 120 is the product of the width W2 and the thickness d2 of the second section 120, and the current-carrying area of the third section 130 is the product of the width W3 and the thickness d3 of the third section 130. The difference in the current-carrying areas between any two of the first section 110, the second section 120, and the third section 130 is less than 5%. Taking the first section 110 and the second section 120 as an example, the ratio of the difference in the current-carrying areas between the first section 110 and the second section 120 to the smaller current-carrying area of the two is less than 5%.

[0084] A smaller difference in the current-carrying areas can make the conduction of current in the connecting piece 10 more uniform, help reduce the generation of resistance and heat, improve the efficiency and service life of the battery, and the current-carrying area can also improve the mechanical strength consistency of the connecting piece 10. When the current-carrying areas of each section are similar, the mechanical strength of the connecting piece 10 as a whole is also more consistent, which helps enhance the stability and durability of the connecting piece 10.

[0085] As a part of the battery system, the performance of the connecting piece 10 directly affects the performance of the entire battery system. When the current-carrying area of the connecting piece 10 is reasonably designed and the difference is small, it can help the battery system have higher efficiency and stability during the charging and discharging process.

[0086] It can be understood that the design with the difference in the current-carrying areas between any two of the first section 110, the second section 120, and the third section 130 being less than 5% helps improve the performance and quality of the connecting piece 10 in the battery cell 1.

[0087] In some embodiments, as Figure 2 shown, the length L2 of the second section 120 is greater than the length L1 of the first section 110 and the length L3 of the third section 130.

[0088] The length L1 of the first section 110 does not exceed the length of the pole 40 connected thereto, the length L3 of the third section 130 does not exceed the length of the ear 520 connected thereto, and the length L2 of the second section 120 is only limited by the internal installation space size of the battery cell 1, and can satisfy: L1 < L2, L3 < L2, so as to obtain a higher current-carrying capacity.

[0089] Increasing the length L2 of the second section 120 can also reduce the local concentration of current in the connecting plate 10, reduce the generation of resistance and heat, and improve the efficiency and service life of the battery. At the same time, it can provide additional mechanical support, enhance the overall stability of the connecting plate 10, and reduce the loosening or damage of the battery under vibration or impact conditions.

[0090] It is understandable that by properly designing the height and shape of the second section 120 , a higher current capacity can be obtained, thereby improving the efficiency and service life of the battery.

[0091] The present application also provides a battery cell 1, such as Figure 3 As shown, the battery cell 1 includes: a shell 20 , a cover 30 , a pole core 50 and a connecting sheet 10 .

[0092] The shell 20 is the external main structure of the battery cell 1, which can form a closed cavity 210 for accommodating and protecting the internal components of the battery. The material of the shell 20 usually has good mechanical strength and chemical stability to improve the safety and reliability of the battery under various environmental conditions.

[0093] The cover 30 is used to seal the cavity 210, and plays the role of protecting the internal structure of the battery and connecting the external circuit. The cover 30 is provided with a pole 40, which is an important component connecting the pole core 50 with the external circuit and is a connecting bridge between the internal circuit of the battery and the external circuit.

[0094] The pole core 50 is the core component of the battery, responsible for storing and releasing electrical energy. In the present application, the pole core 50 includes a current collector 510 and a pole tab 520. The current collector 510 is a carrier of the battery active material, used to collect and conduct current. The pole tab 520 is the connecting part between the current collector 510 and the connecting sheet 10, used to transfer current from the current collector 510 to the connecting sheet 10.

[0095] The connecting piece 10 is responsible for connecting the pole 40 with the pole core 50 in the battery cell 1 to form a complete current path. The connecting piece 10 includes a first section 110 , a second section 120 and a third section 130 . The first section 110 is electrically connected to the pole 40 , and the third section 130 is electrically connected to the pole ear 520 of the pole core 50 .

[0096] It can be understood that the housing 20 and the cover 30 together protect the internal components of the battery from interference and damage from the external environment, while providing the necessary mechanical support and heat dissipation channels to achieve efficient and safe operation of the battery.

[0097] In some embodiments, Figure 1 and Figure 3 As shown, the pole 40 includes a pole body and a lead-out piece 410 , and the first section 110 of the connecting piece 10 is electrically connected to the lead-out piece 410 .

[0098] If the connecting piece 10 is directly electrically connected to the pole body, the contact area is determined by the pole body, resulting in a smaller contact area, which affects the current carrying capacity of the connecting piece 10 . The lead-out piece 410 can increase the contact area with the connecting piece 10 .

[0099] The lead-out plate 410 is a part of the pole 40, and serves to lead the current of the pole 40 and establish an electrical connection with the connecting plate 10. The lead-out plate 410 is usually made of a material with good conductive properties, such as copper, aluminum or alloy, which helps to efficiently conduct current. The shape and size design of the lead-out plate 410 can be accurately calculated and optimized according to the specific needs and spatial layout of the battery to enhance the good fit with the connecting plate 10 and the current conduction performance.

[0100] The first section 110 of the connecting plate 10 and the lead-out plate 410 are electrically connected by welding. The current of the pole 40 can be smoothly transmitted to the first section 110 of the connecting plate 10 through the lead-out plate 410, and then establish an electrical connection with the pole ear 520 of the pole core 50 through the second section 120 and the third section 130 of the connecting plate 10, forming a complete current path.

[0101] It can be understood that the synergistic effect of the pole 40 and the connecting sheet 10 helps to smoothly conduct the current inside the battery cell 1, thereby improving the performance and efficiency of the battery.

[0102] In some embodiments, the connection between the connecting piece 10 and the lead piece 410 and the tab 520 has various structural forms, including but not limited to:

[0103] In example 1, the width W1 of the first section 110 and the width of the lead-out piece 410 are set to be the same, and the first section 110 is fully connected to the lead-out piece 410 by welding.

[0104] like Figure 1 As shown, the width W1 of the first section 110 of the connecting piece 10 is designed to be the same as the width of the lead-out piece 410, which can maximize the welding width of the first section 110 and the lead-out piece 410, and contribute to good contact and current conduction performance between the two. The same width can also reduce thermal stress and deformation during welding and improve welding quality.

[0105] The first section 110 and the lead-out piece 410 are fully welded, that is, the welding surface covers the entire contact area. This connection method can provide higher conductivity and mechanical strength, allowing the current to be smoothly conducted between the two and preventing the connection from loosening or breaking due to vibration or impact.

[0106] Example 2: The width W3 of the third section 130 and the width of the tab 520 are set to be the same, and the third section 130 is fully welded to the tab 520 .

[0107] like Figure 3 As shown, the width W3 of the third section 130 of the connecting piece 10 is designed to be the same as the width of the tab 520, which can maximize the welding width between the third section 130 and the tab 520, and contribute to good contact and current conduction performance between the two. The same width can also reduce thermal stress and deformation during welding and improve welding quality.

[0108] The width W3 of the third section 130 of the connecting piece 10 and the width of the pole tab 520 are fully welded. This connection method can provide higher conductivity and mechanical strength, contribute to good contact and current conduction performance between the third section 130 and the pole tab 520, and enhance the stability of the battery cell 1 structure, while reducing thermal stress and deformation during welding.

[0109] Example three, the width W1 of the first section 110 and the width of the lead-out plate 410 are set to be the same, and the first section 110 and the lead-out plate 410 are fully welded together. At the same time, the width W3 of the third section 130 and the width of the pole ear 520 are also set to be the same, and the third section 130 and the pole ear 520 are fully welded together.

[0110] like Figure 1 and Figure 3 As shown, the width W1 of the first section 110 and the width of the lead-out piece 410 as well as the width W3 of the third section 130 and the width of the pole lug 520 are designed to be the same, respectively, so that the welding widths of the first section 110 and the lead-out piece 410 and the third section 130 and the pole lug 520 can be maximized, which contributes to good contact and current conduction performance between the connecting piece 10 and the lead-out piece 410 and the pole lug 520. The same width can also reduce thermal stress and deformation during welding and improve welding quality.

[0111] The first section 110 and the lead-out piece 410 are fully welded, that is, the welding surface covers the entire contact area. This connection method can provide higher conductivity and mechanical strength, allowing the current to be smoothly conducted between the two and preventing the connection from loosening or breaking due to vibration or impact.

[0112] Similarly, the width of the third section 130 of the connecting plate 10 and the pole lug 520 is also fully welded. This connection method can provide higher conductivity and mechanical strength, contribute to good contact and current conduction performance between the third section 130 and the pole lug 520, and enhance the stability of the battery cell 1 structure, while reducing thermal stress and deformation during welding.

[0113] It can be understood that the first section 110 of the connecting piece 10 and the lead-out piece 410 as well as the third section 130 and the tab 520 are fully welded to significantly improve the smooth conduction performance of the internal current of the battery cell 1 .

[0114] The embodiment of the present application further provides a battery, comprising: a plurality of battery cells 1 .

[0115] In the technical solution of the present application, the battery is composed of a plurality of battery cells 1 to realize the effective transmission and sharing of electric energy. The battery cell 1 is the basic unit of the battery. Each battery cell 1 has independent electric energy storage and output capabilities and is usually composed of a shell 20, a cover 30 and a pole core 50. The pole core 50 is the core part of the battery cell 1 and is used to store electric energy. It is located in the shell 20 and is connected to the external circuit through the pole 40 on the cover 30 to realize the electric energy transmission between the battery cells 1.

[0116] Multiple battery cells 1 form a circuit structure connected in series or in parallel. The series connection can increase the total voltage of the battery, which is suitable for application scenarios that require high voltage output. The parallel connection can increase the total capacity of the battery, which is suitable for application scenarios that require long-term operation or high energy density.

[0117] It can be understood that, through the combination of multiple battery cells 1, the total energy density of the battery can be improved, which is conducive to the effective transmission of electrical energy.

[0118] The embodiment of the present application also provides an electrical device.

[0119] The electric device includes a battery, and the battery is used to provide electric energy to the electric device.

[0120] In the technical solution of the present application, the electrical device is a device or system that relies on electrical energy to work, which may be but is not limited to mobile phones, tablets, laptops, electric cars, and ships, etc., ranging from simple portable electronic devices to complex household appliances and industrial equipment.

[0121] As the main power source of the electrical device, the battery is mainly connected to other parts of the electrical device through the output port. It is responsible for converting chemical energy into electrical energy to provide a continuous and stable power supply for the device. Compared with a fixed power source, the battery has higher portability, allowing the electrical device to work independently without an external power supply. The battery is composed of multiple battery cells 1. The battery cells 1 are connected in a specific way, such as in series or in parallel, to form a whole to provide the required voltage and capacity.

[0122] It is understandable that the electrical device uses an integrated battery as an energy source to drive its internal working mechanism or perform a specific function.

[0123] The following describes the embodiments of the present application in detail from two different implementation perspectives.

[0124] In example 1, the positive electrode tab 520 and the negative electrode tab 520 of the electrode core 50 are both connected to the lead-out tab 410 via the connecting tab 10 .

[0125] The first section 110 of the connecting piece 10 and the lead-out piece 410 are electrically connected by welding, and the third section 130 of the connecting piece 10 and the pole ear 520 are also electrically connected by welding. The current can be smoothly transmitted to the third section 130 of the connecting piece 10 through the pole ear 520 of the pole core 50, and then the second section 120 and the first section 110 of the connecting piece 10 are electrically connected to the lead-out piece 410 of the pole 40 to form a complete current path.

[0126] In this embodiment, the positive electrode of the pole core 50 uses 13um aluminum foil, and the negative electrode uses 8um copper foil. Taking a maximum of 70 groups of aluminum foil stacking as an example, the maximum thickness of the positive electrode tab 520 is 0.91mm, and the maximum thickness of the negative electrode tab 520 is 0.57mm. At the same time, according to the maximum current capacity design, the connecting piece 10 and the tab 520 of the pole core 50 are fully welded to maximize the welding width.

[0127] For example, the connecting piece 10 on the positive electrode side is made of metal aluminum, the width W3 of the third section 130 of the connecting piece 10 is the same as the width of the positive electrode tab 520, and W3=92mm, and the dimensions of other areas of the connecting piece 10 satisfy: the width W1 of the first section 110 is 70mm, the width W2 of the second section 120 is 60mm, and the thickness d1 of the first section 110 is 0.6mm, the thickness d2 of the second section 120 is 1.6mm, and the thickness d3 of the third section 130 is the same as the thickness of the positive electrode tab 520 and is 0.91mm.

[0128] The connecting piece 10 on the negative electrode side is made of metallic copper or copper-nickel composite metal. The width W3 of the third section 130 of the connecting piece 10 is the same as the width of the positive electrode tab 520, and W3=94mm. At the same time, the dimensions of other areas of the connecting piece 10 satisfy: the width W1 of the first section 110 is 66mm, the width W2 of the second section 120 is 60mm, and the thickness d1 of the first section 110 is 0.3mm, the thickness d2 of the second section 120 is 0.88mm, and the thickness d3 of the third section 130 is the same as the thickness of the positive electrode tab 520 and is 0.57mm.

[0129] After being assembled into a battery, it is discharged according to the determined working conditions, wherein the peak current exceeds 2000A, the maximum temperature at the positive electrode tab 520 is 68°C, and the maximum temperature at the negative electrode tab 520 is 66°C.

[0130] In example 2, the negative electrode tab 520 of the electrode core 50 is connected to the lead-out plate 410 via the connecting plate 10 , and the positive electrode tab 520 is directly connected to the lead-out plate 410 .

[0131] The first section 110 of the connecting sheet 10 and the lead-out sheet 410 are electrically connected by welding, and the third section 130 of the connecting sheet 10 and the negative electrode tab 520 are also electrically connected by welding. The current can be smoothly transmitted to the third section 130 of the connecting sheet 10 through the negative electrode tab 520 of the pole core 50, and then the second section 120 and the first section 110 of the connecting sheet 10 are electrically connected to the lead-out sheet 410 of the pole 40 to form a complete current path.

[0132] In this embodiment, the positive electrode of the pole core 50 uses 13um aluminum foil, and the negative electrode uses 8um copper foil. Taking a maximum of 70 groups of aluminum foil stacking as an example, the maximum thickness of the positive electrode tab 520 is 0.91mm, and the maximum thickness of the negative electrode tab 520 is 0.57mm. At the same time, according to the maximum current capacity design, the connecting piece 10 and the negative electrode tab 520 of the pole core 50 are fully welded to maximize the welding width.

[0133] For example, the positive electrode does not use the connecting sheet 10, and the tab 520 is directly welded to the lead-out sheet 410. The width of the positive tab 520 is 70 mm and the thickness is 0.91 mm. The connecting sheet 10 on the negative electrode side is made of metallic copper or copper-nickel composite metal. The width W3 of the third section 130 of the connecting sheet 10 is the same as the width of the positive tab 520, and W3=94 mm. At the same time, the dimensions of other areas of the connecting sheet 10 satisfy: the width W1 of the first section 110 is 66 mm, the width W2 of the second section 120 is 60 mm, and the thickness d1 of the first section 110 is 0.3 mm, the thickness d2 of the second section 120 is 0.88 mm, and the thickness d3 of the third section 130 is the same as the thickness of the positive tab 520 and is 0.57 mm.

[0134] After being assembled into a battery, it is discharged according to the determined working conditions, wherein the peak current exceeds 2000A, the maximum temperature at the positive electrode tab 520 is 68°C, and the maximum temperature at the negative electrode tab 520 is 66°C.

[0135] The different battery cells 1 in the above two embodiments are discharged according to a certain fixed working condition, and the maximum temperatures of the positive electrode tab 520 and the negative electrode tab 520 are measured respectively when the peak current exceeds 2000A, and the following data are obtained:

[0136] After the battery cell 1 in which the positive pole tab 520 and the negative pole tab 520 of the pole core 50 are connected to the lead-out tab 410 through the connecting sheet 10 is assembled into a battery, it is discharged according to the determined working conditions, wherein the peak current exceeds 2000A, the maximum temperature at the positive pole tab 520 is 68°C, and the maximum temperature at the negative pole tab 520 is 66°C.

[0137] The negative pole tab 520 of the pole core 50 is connected to the lead-out plate 410 through the connecting plate 10, and the battery cell 1 in which the positive pole tab 520 is directly connected to the lead-out plate 410 is assembled into a battery and discharged according to the determined working conditions, wherein the peak current exceeds 2000A, the maximum temperature at the positive pole tab 520 is 68°C, and the maximum temperature at the negative pole tab 520 is 66°C.

[0138] At the same time, as shown in the figure, the positive and negative electrodes of the battery cell 1 of the control group do not use the connecting plate 10. The pole ear 520 of the control group is directly welded to the lead-out plate 410. The exposed width of the pole ear 520 is limited and smaller than the width of the pole piece itself. The positive electrode uses 13um aluminum foil and the negative electrode uses 8um copper foil. The width of the positive pole ear 520 is 70mm and the thickness is 0.91mm. The width of the negative pole ear 520 is 66mm and the thickness is 0.57mm.

[0139] After being assembled into a battery, it was also discharged according to the same determined working conditions, with a peak current exceeding 2000A, a maximum temperature at the positive electrode tab 520 of 77°C, and a maximum temperature at the negative electrode tab 520 of 63°C, both exceeding the normal operating range of lithium-ion batteries.

[0140] It can be understood that, through the comparison of the above experimental data, the use of connecting sheet 10 to connect the pole ear 520 and the lead-out sheet 410 can obtain a higher current capacity than directly connecting the pole ear 520 to the lead-out sheet 410. Under high current charging and discharging, the temperature at the pole ear 520 using the connecting sheet 10 is significantly reduced.

[0141] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0142] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0143] In the description of this application, "first feature" or "second feature" may include one or more of the features.

[0144] In the description of the present application, “plurality” means two or more.

[0145] In the description of the present application, a first feature being “on” or “under” a second feature may include that the first and second features are directly in contact with each other, or may include that the first and second features are not in direct contact with each other but are in contact with each other via another feature therebetween.

[0146] In the description of the present application, “above”, “over” and “above” a first feature to a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0147] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0148] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A connecting sheet, applied to a battery cell and connected between a pole ear and a pole, characterized in that: include: Paragraph 1; a second segment, wherein a first end of the second segment is connected to the first segment, and a width of the second segment is smaller than a width of the first segment; The third section is connected to the second end of the second section, and the width of the third section is greater than the width of the second section.

2. The connecting piece according to claim 1, characterized in that: The thickness of the second section is greater than the thickness of the first section and the thickness of the third section.

3. The connecting sheet according to claim 1, characterized in that: The second section includes a first connecting section, a main section and a second connecting section, the first connecting section is connected to the first section, the second connecting section is connected to the third section, and the thickness of the first connecting section and the second connecting section gradually decreases in a direction away from the main section.

4. The connecting piece according to claim 3, characterized in that: A chamfer is provided at the connection between the first connecting section and the first section; and / or, A chamfer is provided at a connection between the second connection section and the third section.

5. The connecting piece according to any one of claims 1 to 4, characterized in that: A difference in flow areas between any two of the first section, the second section and the third section is less than 5%.

6. The connecting piece according to claim 5, characterized in that: The length of the second segment is greater than the length of the first segment and the length of the third segment.

7. A battery cell, characterized in that: include: a shell, forming a cavity; A cover body, used for sealing the cavity, the cover body being provided with a pole; A pole core is installed in the cavity, and the pole core includes a current collector and a pole ear; The connecting piece according to any one of claims 1 to 6, wherein the connecting piece is installed in the cavity, the first section of the connecting piece is electrically connected to the pole, and the third section of the connecting piece is electrically connected to the pole ear.

8. The battery cell according to claim 7, characterized in that: The pole includes a pole body and a lead-out piece, and the first section of the connecting piece is electrically connected to the lead-out piece.

9. The battery cell according to claim 8, characterized in that: The width of the first section of the connecting piece is the same as the width of the lead-out piece, and the first section is fully connected to the lead-out piece by welding; and / or, The width of the third section of the connecting sheet is the same as the width of the pole lug, and the third section is fully welded to the pole lug.

10. A battery, characterized in that: include: A plurality of battery cells as claimed in claim 9.

11. An electrical device, characterized in that: include: The battery as claimed in claim 10, wherein the battery is used to provide electrical energy to the electrical device.

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