Winding type battery cell, battery monomer, battery and electric equipment

Abstract

The utility model discloses a winding type battery cell, a battery monomer, a battery and electric equipment, and relates to the technical field of batteries, the winding type battery cell comprises an electrode assembly, the electrode assembly comprises a body part and an electrode lead-out part, and the body part is wound by taking a first axis as a rotating shaft; the electrode leading-out part is connected with the body part and comprises a positive terminal and a negative terminal, and the positive terminal and the negative terminal are arranged at an interval and are arranged at the same end of the body part in the direction parallel to the first axis. According to the winding type battery cell, the battery monomer, the battery and the electric equipment provided by the technical scheme of the utility model, the energy density of the winding type battery cell is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a wound battery cell, a battery cell, a battery and an electrical device. Background Technology

[0002] A wound battery cell is formed by stacking positive electrode plates, negative electrode plates, and a separator in an alternating manner and then winding them together. Traditional wound battery cells typically use a full-tab configuration, where the positive and negative electrode tabs are located at opposite ends of the cell and flattened to serve as the positive and negative electrodes, respectively.

[0003] However, this arrangement inevitably increases the structural size of the cell at the flattened tabs at both ends, reducing the space utilization rate when the cell is used in a battery cell, which is not conducive to improving energy density.

[0004] Therefore, there is an urgent need to design a new type of wound battery cell to solve the above problems. Utility Model Content

[0005] The main purpose of this invention is to provide a wound battery cell, a battery cell, a battery, and an electrical device, with the aim of improving the energy density of the wound battery cell.

[0006] To achieve the above objectives, this utility model provides a wound battery cell, which includes an electrode assembly. The electrode assembly includes a body portion and an electrode lead portion. The body portion is wound around a first axis as the axis of rotation. The electrode lead portion is connected to the body portion and includes a positive terminal and a negative terminal. The positive terminal and the negative terminal are spaced apart and disposed at the same end of the body portion along a first direction, which is parallel to the first axis.

[0007] In some embodiments, the wound cell further includes two current collectors, which are respectively connected to the positive terminal and the negative terminal.

[0008] In some embodiments, the manifold includes a welding portion and a metal lead, the projection of the electrode lead onto the welding portion along a first direction falls on the welding portion, and the metal lead is connected to the welding portion and used to connect to the electrode post.

[0009] In some embodiments, the wound cell further includes an insulating element that covers the welded portion.

[0010] In some embodiments, the insulating member includes a main body, a groove, and a through groove. The main body is connected to the welding part and is disposed at one end of the welding part away from the electrode lead-out part. The groove is disposed at one end of the main body near the welding part. The through groove passes through the main body in a first direction. The welding part is engaged in the groove, and the metal lead is used to pass through the through groove and connect to the electrode post.

[0011] In some embodiments, both the current collector and the insulating element have a fan-shaped cross-sectional shape perpendicular to the first direction.

[0012] In some embodiments, the central angle of the current collector in a cross-section perpendicular to the first direction and the central angle of the insulator in a cross-section perpendicular to the first direction are both α, and 90°. <a<120°。

[0013] This utility model embodiment also provides a battery cell, which includes a shell, an end cap, and a wound cell as provided in any of the preceding embodiments; wherein the shell and the end cap together form an accommodating space, the end cap is provided with a positive terminal and a negative terminal for connecting to an electrical device, the wound cell is accommodated in the accommodating space, and the positive terminal is connected to the positive terminal and the negative terminal is connected to the negative terminal.

[0014] This utility model embodiment also provides a battery, including a battery cell as provided in any of the foregoing embodiments.

[0015] This utility model embodiment also provides an electrical device, including a battery as provided in any of the foregoing embodiments, the battery being used to provide electrical energy.

[0016] The technical solution of this utility model reduces the structural size of the wound cell in the first direction by placing the positive and negative terminals at the same end of the body part along the first direction. This is beneficial to improving the design size of the body part that actually performs the charging and discharging functions, and thus improving the energy density of the wound cell. At the same time, by placing the positive and negative terminals at the same end of the body part along the first direction, the electrolyte can be wetted through the end of the body part away from the positive and negative terminals, improving the wetting efficiency of the electrolyte. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a three-dimensional structural diagram of the wound battery cell provided by this utility model;

[0019] Figure 2 yes Figure 1 An enlarged view of part A of the wound battery cell shown;

[0020] Figure 3 This is a three-dimensional structural diagram of the tabs of the positive and negative electrode sheets in the wound battery cell provided by this utility model after they have been flattened.

[0021] Figure 4 This is a structural schematic diagram of an insulating component at one angle in the wound battery cell provided by this utility model;

[0022] Figure 5 This is a structural schematic diagram of the insulating component in the wound battery cell provided by this utility model from another angle;

[0023] Figure 6 This is a schematic diagram of the structure of the positive and negative electrode sheets of the wound battery cell provided by this utility model after being die-cut to form electrode sheets with tabs.

[0024] Figure 7 This is a three-dimensional structural diagram of the battery cell provided by this utility model.

[0025] Explanation of icon numbers:

[0026] 1000, Battery cell; 200, Casing; 300, End cap; 301, Positive terminal; 302, Negative terminal;

[0027] 100. Winded cell; 10. Electrode assembly; 11. Body; 12. Electrode lead-out section; 121. Positive terminal; 122. Negative terminal; 20. Current collector; 21. Welding section; 22. Metal lead strip; 30. Insulating component; 31. Main body; 32. Groove; 33. Through slot;

[0028] O, first axis; X, first direction.

[0029] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0031] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0032] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0033] A wound battery cell is formed by stacking positive electrode plates, negative electrode plates, and a separator in an alternating manner and then winding them together. Traditional wound battery cells typically use a full-tab configuration, where the positive and negative electrode tabs are located at opposite ends of the cell and flattened to serve as the positive and negative electrodes, respectively.

[0034] However, this arrangement inevitably increases the structural size of the cell at the flattened tabs at both ends, reducing the space utilization rate when the cell is used in a battery cell, which is not conducive to improving energy density. At the same time, since the tabs at both ends of the cell are flattened, the sealing performance at both ends of the cell is high. This increases the efficiency of electrolyte wetting of the internal electrode sheets of the cell during the electrolyte wetting stage, which can easily lead to uneven or insufficient electrolyte wetting.

[0035] Based on this, the inventors provide a new type of wound battery cell, which aims to reduce the structural size of the wound battery cell by placing the positive and negative electrode tabs of the wound battery cell on the same end of the electrode assembly, thereby improving the energy density of the wound battery cell; at the same time, the electrolyte can also wet the electrode sheet from the end without the tabs, thus greatly improving the wetting efficiency of the electrolyte.

[0036] Please refer to the following: Figures 1 to 6 This utility model embodiment proposes a wound battery cell 100, which includes an electrode assembly 10. The electrode assembly 10 includes a body portion 11 and an electrode lead-out portion 12. The body portion 11 is wound around a first axis O. The electrode lead-out portion 12 is connected to the body portion 11 and includes a positive terminal 121 and a negative terminal 122. The positive terminal 121 and the negative terminal 122 are spaced apart and disposed at the same end of the body portion 11 along a first direction X, which is parallel to the first axis O.

[0037] The wound cell 100 is a battery core structure formed by winding a positive electrode sheet, a negative electrode sheet and a separator in an alternating manner. Due to its high energy density, high cycle life and easy assembly, the wound cell 100 has been widely used in mobile devices and electric vehicles.

[0038] The electrode assembly 10 includes a body portion 11 and an electrode lead-out portion 12. The body portion 11 is the component in the wound battery cell 100 that is actually used to release or store electrical energy. In these embodiments of the present invention, the body portion 11 may include a positive electrode, a negative electrode, and a separator. The positive and negative electrode are staggered along a direction perpendicular to the first axis, and the separator is disposed between adjacent positive and negative electrode portions. Thus, after being immersed in electrolyte, electrons can pass through the separator and move between the positive and negative electrode portions, thereby realizing charging and discharging.

[0039] The main body 11 is wound around a first axis O, where the first axis O is a virtual axis, meaning that the main body 11 is wound into a winding structure to make the structure more compact.

[0040] The electrode lead-out portion 12 is connected to the body portion 11 and includes a positive terminal 121 and a negative terminal 122. The electrode lead-out portion 12 is an electrical transmission component. The electrode lead-out portion 12 is connected to the body portion 11 to transfer external electrical energy to the body portion 11 during the charging phase to achieve charging; or to transfer the electrical energy generated by the body portion 11 to the outside during the discharging phase.

[0041] In these embodiments of the present invention, the positive terminal 121 is used to connect to the aforementioned positive electrode sheet. For example, the positive terminal 121 can be a collection of tabs of the aforementioned positive electrode sheet, formed after a flattening process. Correspondingly, the negative terminal 122 is used to connect to the aforementioned negative electrode sheet. The negative electrode sheet 122 can also be a collection of tabs of the aforementioned negative electrode sheet, formed after a flattening process.

[0042] In these embodiments of the present invention, the positive terminal 121 and the negative terminal 122 may be formed in the following ways:

[0043] First, select positive and negative electrode sheets respectively, and perform die-cutting or laser cutting on the positive and negative electrode sheets respectively, so that the empty foil parts that serve as tabs in the positive and negative electrode sheets are of equal width but unequal spacing, so that in the subsequent winding process, as the winding thickness increases, the tabs of the same polarity can still be located on the same side of the winding structure.

[0044] The formed positive and negative electrode sheets are wound together, with the tabs of the positive and negative electrode sheets located at the same end. It should be noted that, because the tabs of the positive and negative electrode sheets are located at the same end, during the aforementioned die-cutting of the positive and negative electrode sheets, it is necessary to control the tabs to be misaligned so that during the subsequent winding process, multiple tabs of the positive electrode sheet and multiple tabs of the negative electrode sheet can contact each other, and the positive and negative electrode sheets are spaced apart on an annular cross-section perpendicular to the first direction X.

[0045] The tabs of the positive electrode and the negative electrode are flattened respectively, so that the multiple tabs of the positive electrode form a positive terminal 121 and the multiple tabs of the negative electrode form a negative terminal 122.

[0046] In these embodiments of the present invention, compared with the structure of the two-sided tabs of the conventional technology, the present invention reduces the structural size of the wound cell 100 in the first direction X by setting the positive terminal 121 and the negative terminal 122 at the same end of the body portion 11 along the first direction X. This is beneficial to improving the design size of the body portion 11 that actually performs the charging and discharging functions, and thus improving the energy density of the wound cell 100. At the same time, by setting the positive terminal 121 and the negative terminal 122 at the same end of the body portion 11 along the first direction X, the electrolyte can be wetted through the end of the body portion 11 away from the positive terminal 121 and the negative terminal 122, thereby improving the wetting efficiency of the electrolyte.

[0047] In some embodiments, the wound cell 100 further includes two current collectors 20, which are respectively connected to the positive terminal 121 and the negative terminal 122.

[0048] The function of the current collector 20 is to conduct electricity, enabling the electrode assembly 10 to be electrically connected to the outside world, thereby realizing charging or discharging.

[0049] In these embodiments of the present invention, two current collectors 20 are provided, so that the two current collectors 20 are respectively connected to the positive terminal 121 and the negative terminal 122. One possible implementation for connecting the current collector 20 to the positive terminal 121 is that after the multiple tabs of the positive electrode sheet are flattened to form the positive terminal 121, a current collector 20 is welded to the positive terminal 121 to improve the structural consistency between the current collector 20 and the positive terminal 121, thereby improving current transmission efficiency. The connection between the current collector 20 and the negative terminal 122 is similar and will not be described further here.

[0050] In some embodiments of this utility model, the connection between the current collector 20 and the positive terminal 121 or the negative terminal can also be achieved by using an assembly structure to press the current collector 20 against the positive terminal 121 or the negative terminal 122 to enable current conduction.

[0051] In some embodiments, the manifold 20 includes a welding portion 21 and a metal lead 22. The projection of the electrode lead 12 toward the welding portion 21 in the first direction X falls on the welding portion 21. The metal lead 22 is connected to the welding portion 21 and is used to connect with the electrode post.

[0052] The function of the welding part 21 is to weld to the positive terminal 121 or the negative terminal 122 to form a current conduction structure with higher structural consistency.

[0053] The metal lead 22 is used to weld to the terminal post, so as to connect the positive terminal 121 or the negative terminal 122 to an external electrical device or power source through the terminal post. In these embodiments of this utility model, the welded part 21 after welding to the positive terminal 121 or the negative terminal 122 is connected to the terminal post by the metal lead 22. Because the metal lead 22 has a certain degree of flexibility, it can be bent or folded to adapt to the structure of different battery casings during installation.

[0054] The projection of the electrode lead-out portion 12 onto the welding portion 21 along the first direction X is intended to increase the contact area between the electrode lead-out portion 12 and the welding portion 21, thereby improving the overcurrent effect of the electrode lead-out portion 12 and the welding portion 21 during current conduction and improving the charging or discharging efficiency of the wound cell 100 during operation.

[0055] The metal lead 22 is connected to the welding part 21 and used to connect to the pole post. In a possible implementation, one end of the metal lead 22 is welded to the welding part 21. Alternatively, in some embodiments, the metal lead 22 and the welding part 21 can be integrally formed.

[0056] The metal lead 22 is connected to the pole post. One possible implementation is that the metal lead 22 is welded to the pole post to improve the connection stability between the metal lead 22 and the pole post. Alternatively, in some embodiments, the metal lead 22 and the pole post can be detachably connected by external connectors such as screws to reduce the difficulty of subsequent maintenance or replacement and further improve efficiency.

[0057] In some embodiments, the wound cell 100 further includes an insulating element 30 that covers the welded portion 21.

[0058] The insulating component 30 serves to improve the insulation and sealing performance of the welded part 21. After the wound cell 100 is assembled into the housing, it can reduce the probability of the welded part 21 coming into contact with moisture, thereby reducing the risk of external moisture condensing into water droplets at the welded part 21 and causing a short circuit inside the electrode assembly 10. On the other hand, it can also reduce the risk of the welded part 21 coming into contact with the housing and short-circuiting during transportation or use, further improving the structural stability and reliability of the wound cell 100.

[0059] The insulating component 30 covers the welded portion 21. In a possible implementation, the main structure of the insulating component 30 is disposed at the end of the welded portion 21 away from the main body portion 11. At the same time, a portion of the insulating component 30 is disposed on the side of the welded portion 21 perpendicular to the first direction X. In this way, the end of the welded portion 21 close to the main body portion 11 is in contact with the main body portion 11. Meanwhile, the insulating component 30 is in contact with the welded portion 21 at the end of the welded portion 21 away from the main body portion 11 and at the side position perpendicular to the first direction X. Together, they improve the insulation performance of the welded portion 21.

[0060] In some embodiments, the insulating member 30 includes a main body 31, a groove 32, and a through groove 33. The main body 31 is connected to the welding part 21 and is disposed at one end of the welding part 21 away from the electrode lead-out part 12. The groove 32 is disposed at one end of the main body 31 near the welding part 21. The through groove 33 passes through the main body 31 along the first direction X. The welding part 21 is engaged in the groove 32, and the metal lead 22 is used to pass through the through groove 33 and connect to the electrode post.

[0061] The main body 31 is connected to the welding part 21. One possible way is that the main body 31 is fixedly connected to the welding part 21 by adhesive bonding, so as to improve the connection stability between the main body 31 and the welding part 21 and improve the structural stability of the wound cell 100 during transportation or drop.

[0062] The main body 31 is provided at one end of the welding part 21 away from the electrode lead-out part 12 to improve the sealing and insulation performance of the welding part 21 at that end.

[0063] The function of the groove 32 is to cover the welded part 21. That is, during the assembly process of the wound cell 100, after the welded part 21 is welded to the positive terminal 121 or the negative terminal 122, the groove 32 can be aligned with the welded part 21 and then covered. At this time, the groove wall of the groove 32 is located at the periphery of the welded part 21 to cover the side of the welded part 21, thereby reducing the probability of the welded part 21 contacting other components and improving the insulation performance of the welded part 21.

[0064] The through slot 33 penetrates through the main body portion 31 along the first direction X. In this way, during the installation process of the insulating member 30, the metal lead strip 22 can be passed through the through slot 33 along the first direction X, so that while the insulating member 30 provides insulation for the welding portion 21, the influence on the electrical conduction function of the current collector plate 20 is reduced, and the reliability of the electrical conduction of the wound battery cell 100 is improved.

[0065] In some embodiments, the cross-sectional shapes of the current collector plate 20 and the insulating member 30 in a plane perpendicular to the first direction X are both fan-shaped.

[0066] The cross-sectional shape of the current collector plate 20 in a plane perpendicular to the first direction X is fan-shaped, aiming to cover all the tabs of the positive electrode plate or all the tabs of the negative electrode plate.

[0067] In these embodiments of the present utility model, during the winding process of the electrode plate group, it is inevitable that there are errors in the winding process of the multiple tabs of the positive electrode plate, so that the tabs of the multiple positive electrode plates present a fan-shaped structure when being flattened, and the same is true for the negative electrode plate. Thus, the current collector plate 20 can be used to cover the flattened multiple positive tabs or multiple negative tabs, improving the electrical conductivity of the wound battery cell 100.

[0068] The shape of the insulating member 30 matches that of the current collector plate 20 and its projection in the first direction X is slightly larger than the projection of the current collector plate 20 in the first direction X, so as to better wrap the welding portion 21 and improve the insulation performance of the welding portion 21.

[0069] In some embodiments, the central angle of the current collector plate 20 in the cross-section perpendicular to the first direction X and the central angle of the insulating member 30 in the cross-section perpendicular to the first direction X are both a, and 90° < a < 120°.

[0070] In these embodiments of the present utility model, by setting 90° < a < 120°, that is, the central angle of the current collector plate 20 in the cross-section perpendicular to the first direction X is greater than 90° and less than 120°. Among them, by setting the central angle of the current collector plate 20 in the cross-section perpendicular to the first direction X to be greater than 90°, the purpose is to improve the fault tolerance in the tab winding-flattening process and reduce the production precision requirements; by setting the central angle of the current collector plate 20 in the cross-section perpendicular to the first direction X to be less than 120°, the insulation performance between the positive terminal 121 and the negative terminal 122 can be improved, that is, two blank areas are provided between the fan-shaped positive terminal 121 and negative terminal 122, reducing the possibility of their short circuit and further improving the reliability of the wound battery cell 100.

[0071] [[ID=二十ー]]Please refer to Figures 1 to 7This utility model embodiment also provides a battery cell 1000, which includes a housing 200, an end cap 300, and a wound cell 100 as provided in any of the preceding embodiments; wherein, the housing 200 and the end cap 300 together form an accommodating space, the end cap 300 is provided with a positive terminal 301 and a negative terminal 302 for connecting to an electrical device, the wound cell 100 is accommodated in the accommodating space, and the positive terminal 121 is connected to the positive terminal 301, and the negative terminal 122 is connected to the negative terminal 302.

[0072] The outer casing 200 and end cap 300 are external structural components of the battery cell 1000, used to create a sealed and stable working environment. During the production of the battery cell 1000, the wound cell 100 is first placed into the outer casing 200. Then, the metal lead 22 of the current collector 20 connected to the positive terminal 121 is welded and fixed to the positive terminal post 301, and the metal lead 22 of the current collector 20 connected to the negative terminal 122 is welded and fixed to the negative terminal post 302. Finally, the end cap 300 is connected to the outer casing 200, and electrolyte is injected to form a battery cell 1000.

[0073] This utility model embodiment also provides a battery, including a battery cell 1000 as provided in any of the foregoing embodiments.

[0074] This utility model embodiment also provides an electrical device, including a battery as provided in any of the foregoing embodiments, the battery being used to provide electrical energy.

[0075] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A wound battery cell, characterized in that, Includes an electrode assembly, the electrode assembly comprising: The main body is wound around the first axis as the pivot; An electrode lead-out portion is connected to the main body portion and includes a positive terminal and a negative terminal. The positive terminal and the negative terminal are spaced apart and disposed at the same end of the main body portion along a first direction, which is parallel to the first axis.

2. The wound battery cell as described in claim 1, characterized in that, The wound cell also includes two current collectors, which are respectively connected to the positive terminal and the negative terminal.

3. The wound battery cell as described in claim 2, characterized in that, The collector plate includes a welding part and a metal lead strip. The projection of the electrode lead-out part onto the welding part along a first direction falls on the welding part. The metal lead strip is connected to the welding part and is used to connect to the electrode post.

4. The wound battery cell as described in claim 3, characterized in that, The wound cell also includes an insulating component that covers the welded portion.

5. The wound battery cell as described in claim 4, characterized in that, The insulating component includes a main body, a groove, and a through groove. The main body is connected to the welding part and is disposed at one end of the welding part away from the electrode lead-out part. The groove is disposed at one end of the main body near the welding part. The through groove passes through the main body along the first direction. The welding part is engaged in the groove, and the metal guide is used to pass through the through groove and connect to the pole post.

6. The wound battery cell as described in claim 4, characterized in that, Both the current collector and the insulating component have a fan-shaped cross-section perpendicular to the first direction.

7. The wound battery cell as described in claim 6, characterized in that, The central angle of the current collector in a cross-section perpendicular to the first direction and the central angle of the insulating element in a cross-section perpendicular to the first direction are both α, and both are 90°. <a<120°。 8. A single battery cell, characterized in that, Includes a housing, end caps, and a wound cell as described in any one of claims 1 to 7; The outer casing and the end cap together form an accommodating space. The end cap is provided with a positive terminal and a negative terminal for connecting to electrical equipment. The wound battery cell is accommodated in the accommodating space, and the positive terminal is connected to the positive terminal and the negative terminal is connected to the negative terminal.

9. A battery, characterized in that, Includes the battery cell as described in claim 8.

10. An electrical appliance, characterized in that, Includes the battery as described in claim 9, wherein the battery is used to provide electrical energy.

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