A wound battery
By designing strip-shaped electrode plates and tab structures in the wound battery, ensuring that the distance between adjacent tabs is ≤10mm, uniform current distribution is achieved, solving the safety hazards of wound batteries during fast charging and improving battery safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA AVIATION LITHIUM BATTERY RES INST CO LTD
- Filing Date
- 2025-07-17
- Publication Date
- 2026-07-14
Smart Images
Figure CN224501982U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of lithium battery technology, and more specifically, to a wound battery. Background Technology
[0002] In existing technologies, wound batteries are typically formed by stacking and winding positive and negative electrode sheets. Positive and negative tabs are respectively provided on the positive and negative electrode sheets to conduct and guide the current of the wound battery. However, as the size of wound batteries increases, the demand for fast charging gradually increases, which causes the current carried by the tabs on the electrode sheets to gradually increase, leading to local overheating and other phenomena in the wound battery, posing a safety hazard.
[0003] In conclusion, how to reduce the safety hazards during the use of wound batteries is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content
[0004] In view of this, the purpose of this application is to provide a wound battery that reduces safety hazards during the use of wound batteries.
[0005] To achieve the above objectives, this application provides the following technical solution:
[0006] A wound battery includes: a positive electrode sheet and a negative electrode sheet; both the positive electrode sheet and the negative electrode sheet are strip-shaped sheet structures, and the positive electrode sheet and the negative electrode sheet are stacked and wound along their length direction to form the wound battery; a plurality of positive electrode tabs are arranged on one side of the positive electrode sheet along its length direction, and a plurality of negative electrode tabs are arranged on one side of the negative electrode sheet along its length direction; each turn of the positive electrode sheet has at least two positive electrode tabs, and each turn of the negative electrode sheet has at least two negative electrode tabs; the distance between adjacent positive electrode tabs is d, and the distance between adjacent negative electrode tabs is d; wherein, d≤10mm.
[0007] In some embodiments, the positive electrode tab and the positive electrode sheet are an integral structure, and the positive electrode tab extends out of the positive electrode sheet along the width direction of the positive electrode sheet; the negative electrode tab and the negative electrode sheet are an integral structure, and the negative electrode tab extends out of the negative electrode sheet along the width direction of the negative electrode sheet.
[0008] In some embodiments, the height direction of the positive electrode tab is consistent with the width direction of the positive electrode sheet, and the height direction of the negative electrode tab is consistent with the width direction of the negative electrode sheet; the height of both the positive electrode tab and the negative electrode tab is h.
[0009] In some embodiments, d and h are positively correlated.
[0010] In some embodiments, when h is 3 mm, d is 5 mm.
[0011] In some embodiments, when h is 30 mm, d is 10 mm.
[0012] In some embodiments, the positive electrode tab and the positive electrode sheet of the integral structure, as well as the negative electrode tab and the negative electrode sheet of the integral structure, are all formed by die-cutting from the same sheet.
[0013] In some embodiments, the die-cutting speed is 200mm / s-2000mm / s.
[0014] In some embodiments, on the formed wound battery, the positive tab and the negative tab are both located on the same side of the wound battery; and all the positive tabs overlap in the thickness direction of the wound battery, and all the negative tabs overlap in the thickness direction of the wound battery.
[0015] In some embodiments, both the positive electrode tab and the positive electrode sheet are made of aluminum; both the negative electrode tab and the negative electrode sheet are made of copper.
[0016] The wound battery provided in this application includes a positive electrode sheet and a negative electrode sheet, both of which are strip-shaped sheet structures. The positive and negative electrode sheets are stacked and wound along their length to form a wound battery. A number of positive tabs are arranged on one side of the positive electrode sheet along its length, and a number of negative tabs are arranged on one side of the negative electrode sheet along its length. During the winding process of the positive and negative electrode sheets, each turn of the positive electrode sheet has at least two positive tabs, and each turn of the negative electrode sheet has at least two negative tabs. The distance between adjacent positive tabs and the distance between adjacent negative tabs are both less than or equal to 10 mm. This allows current to be transmitted through multiple tabs, shortens the current transmission path, improves the uniformity of current distribution, reduces the current carried by each tab, reduces local overheating, and reduces safety hazards during the use of the wound battery. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of this application 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 embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.
[0018] Figure 1 This is a schematic diagram of the unfolding of wound battery electrodes in the prior art;
[0019] Figure 2 This is a schematic diagram of the structure of a wound battery provided in an embodiment of this application;
[0020] Figure 3This is a schematic diagram of the unfolded electrode sheet of a wound battery provided in an embodiment of this application;
[0021] Figure 4 This application provides a method for die-cutting electrodes.
[0022] Figure 5 This application provides another electrode die-cutting method in its embodiments;
[0023] Figure 6 This provides another electrode die-cutting method for embodiments of this application.
[0024] Explanation of reference numerals in the attached figures:
[0025] 100 - Positive electrode plate, 110 - Positive electrode tab;
[0026] 200 - Negative electrode plate, 210 - Negative electrode tab;
[0027] 300 - Waste Department. Detailed Implementation
[0028] 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, and 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.
[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. The terminology used in the following embodiments is for the purpose of describing specific embodiments only and is not intended to be a limitation of this application. As used in the specification and appended claims of this application, the singular expressions "a," "an," "the," "the," "the," and "this" are intended to also include expressions such as "one or more," unless the context clearly indicates otherwise.
[0030] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.
[0031] The terms "parallel" and "perpendicular" used in this application refer to "basically parallel" and "basically perpendicular" in practical operation. "Basically parallel" can be understood as parallelism with a certain degree of error, and similarly, "basically perpendicular" can be understood as perpendicularity with a certain degree of error.
[0032] like Figure 1 As shown, in the prior art, the spacing between the tabs on the electrode sheet is too large. As the size of the wound battery increases, the demand for fast charging of the battery gradually increases. This results in the tabs carrying too much current after the electrode sheets are wound to form a wound battery, causing local overheating between the tabs and the electrode sheet. This may lead to the tabs breaking, which poses a safety hazard during the use of the wound battery.
[0033] Therefore, this application provides a wound battery that reduces safety hazards during the use of wound batteries.
[0034] like Figure 2 As shown, the wound battery provided in this embodiment includes a positive electrode 100 and a negative electrode 200. Both the positive electrode 100 and the negative electrode 200 are strip-shaped sheet structures, and are stacked along their length and then simultaneously wound to form a wound battery. A plurality of positive tabs 110 are arranged on one side of the positive electrode 100 along its length, and a plurality of negative tabs 210 are arranged on one side of the negative electrode 200 along its length. During the stacking and winding process of the positive electrode 100 and the negative electrode 200, each turn of the positive electrode 100 has at least two positive tabs 110. Each turn of the negative electrode sheet 200 has at least two negative tabs 210; the spacing between adjacent positive tabs 110 is d, and the spacing between adjacent negative tabs 210 is also d, and d≤10mm; in this way, current can be transmitted through multiple positive tabs 110 and multiple negative tabs 210, which shortens the current transmission path, improves the uniformity of current distribution, reduces the current carried by each tab, reduces the phenomenon of local overheating, and reduces the safety hazards during the use of the wound battery.
[0035] It should be noted that both the positive electrode 100 and the negative electrode 200 are elongated structures. It can be understood that both the positive electrode 100 and the negative electrode 200 have relatively distributed length and width directions, and their length direction is longer than their width direction, and their length and width directions are perpendicular to each other.
[0036] like Figure 2 As shown, on the formed wound battery, the positive tab 110 and the negative tab 210 are both located on the same side of the wound battery, so that the positive and negative current flows in the same direction, reducing the eddy current inside the wound battery current, further shortening the current transmission path, and facilitating precise alignment during the operation of the wound battery, thus improving the ease of use.
[0037] like Figure 2 As shown, all the positive tabs 110 overlap in the thickness direction of the wound battery, and all the negative tabs 210 overlap in the thickness of the wound battery, so that the positive tabs 110 and the negative tabs 210 are coaxially aligned, which concentrates the heat source, so as to facilitate heat dissipation, improve heat dissipation efficiency, and further reduce safety hazards during the operation of the wound battery.
[0038] like Figure 3 As shown, the positive electrode tab 110 and the positive electrode plate 100 are an integral structure, and the positive electrode tab 110 extends out of the positive electrode plate 100 along the width direction of the positive electrode plate 100; the negative electrode tab 210 and the negative electrode plate 200 are an integral structure, and the negative electrode tab 210 extends out of the negative electrode plate 200 along the width direction of the negative electrode plate 200.
[0039] Specifically, the positive electrode 100 and the positive electrode tab 110, as well as the negative electrode 200 and the negative electrode tab 210, are all formed from the same sheet material by die cutting.
[0040] In this embodiment, both the positive electrode tab 110 and the positive electrode sheet 100 are made of aluminum, which can be understood as being formed by die-cutting from the same aluminum foil sheet, so as to ensure the high voltage stability of the positive electrode through the aluminum foil sheet.
[0041] Both the negative electrode tab 210 and the negative electrode sheet 200 are made of copper, which can be understood as being formed by die-cutting from the same copper foil sheet, so as to ensure the high conductivity and low potential inertia of the negative electrode. In this way, the positive electrode sheet 100 and the positive electrode tab 110 formed by die-cutting from aluminum foil sheet, and the negative electrode sheet 200 and the negative electrode tab 210 formed by die-cutting from copper foil sheet are stacked and wound to form a wound battery, so as to ensure the normal use of the wound battery.
[0042] like Figure 3 As shown, the height direction of the positive electrode tab 110 is consistent with the width direction of the positive electrode plate 100, and the height of the positive electrode tab 110 is h; the height direction of the negative electrode tab 210 is consistent with the width direction of the negative electrode plate 200, and the height of the negative electrode tab 210 is h.
[0043] During the die-cutting process, as the height h of the tab increases, the tension of the die-cut foil on both sides of the tab changes. In order to ensure the stability of the foil tension and the uniformity of the current distribution on the multiple tabs, as the height h of the tab increases, the spacing d between adjacent tabs needs to be increased accordingly, and d is positively correlated with h.
[0044] In some embodiments, when the height h of the tab is 3 mm, the spacing d between adjacent tabs is 5 mm to ensure the stability of the foil tension during the die-cutting process.
[0045] In some other embodiments, when the height h of the electrode is 30 mm, the spacing d between adjacent electrodes is 10 mm.
[0046] In the embodiments of this application, the electrode sheet and the electrode tab can be formed by various die-cutting methods.
[0047] In some embodiments, such as Figure 4 As shown, it can be formed by a die-cutting method that generates a continuous waste section 300. Die-cutting the same sheet of foil results in a gap distance 'a' between the top edge of the formed tab and the side edge of the foil, making the generated waste section 300 a continuous strip of waste, thus making the foil die-cutting process more stable.
[0048] In some embodiments, the interval distance 'a' is selected as 1 mm to minimize the amount of waste material 300 and reduce costs. Of course, the value of 'a' can be selected according to the actual situation, and this application embodiment does not limit this.
[0049] In some other embodiments, such as Figure 5 As shown, it can be formed by die-cutting to generate a waste section 300. During the die-cutting process of the same foil, the top edge of the tab coincides with the side edge of the foil, so that the waste section 300 generated consists of several fragmented waste edges, reducing the proportion of the waste section 300 and lowering costs.
[0050] In other embodiments, such as Figure 6 As shown, it can be formed by a die-cutting method that generates intermittent waste sections 300. Die-cutting the same sheet of foil such that the top edge of the formed tab has a gap distance 'a' between it and the side edge of the foil, the intermittent waste section 300 can be formed by a cutting-out and re-cutting process after die-cutting every two tabs; specifically, as shown... Figure 6 As shown, at the position where the tab needs to be cut out, first make a horizontal cut from step 1 to step 2, then cut out using step 2, then cut into the corresponding position of the tab using step 3, and then continue to complete the die cutting of the tab using step 4.
[0051] In the process of die-cutting to form tabs and electrode sheets in this application embodiment, the die-cutting speed is 200mm / s-2000mm / s to ensure the stability of the die-cut tabs.
[0052] The wound battery provided in this application embodiment is formed by stacking and winding positive electrode 100 and negative electrode 200, such that each turn of the positive electrode 100 has at least two positive electrode 100 and each turn of the negative electrode 200 has at least two negative electrode 200. The spacing between adjacent positive electrode tabs 110 and the spacing between adjacent negative electrode tabs 210 are both less than or equal to 10mm, so that current can be transmitted through multiple positive electrode tabs 110 and multiple negative electrode tabs 210, shortening the current transmission path, improving the uniformity of current distribution, reducing the current carried by each electrode tab, reducing local overheating, and reducing safety hazards during the use of the wound battery.
[0053] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A wound battery, characterized in that, include: Positive electrode (100) and negative electrode (200); The positive electrode (100) and the negative electrode (200) are both strip-shaped sheet structures, and the positive electrode (100) and the negative electrode (200) are stacked and wound along their length to form the wound battery; The positive electrode (100) has a plurality of positive electrode tabs (110) arranged on one side along its length direction, and the negative electrode (200) has a plurality of negative electrode tabs (210) arranged on one side along its length direction. Each turn of the positive electrode (100) has at least two positive tabs (110), and each turn of the negative electrode (200) has at least two negative tabs (210). The spacing between adjacent positive electrode tabs (110) is d, and the spacing between adjacent negative electrode tabs (210) is d; Where d≤10mm.
2. The wound battery according to claim 1, characterized in that, The positive electrode tab (110) and the positive electrode plate (100) are an integral structure, and the positive electrode tab (110) extends out of the positive electrode plate (100) along the width direction of the positive electrode plate (100). The negative electrode tab (210) and the negative electrode sheet (200) are an integral structure, and the negative electrode tab (210) extends out of the negative electrode sheet (200) along the width direction of the negative electrode sheet (200).
3. The wound battery according to claim 2, characterized in that, The height direction of the positive electrode tab (110) is consistent with the width direction of the positive electrode plate (100), and the height direction of the negative electrode tab (210) is consistent with the width direction of the negative electrode plate (200). The height of the positive electrode (110) and the height of the negative electrode (210) are both h.
4. The wound battery according to claim 3, characterized in that, There is a positive correlation between d and h.
5. The wound battery according to claim 4, characterized in that, With h = 3mm, d = 5mm.
6. The wound battery according to claim 4, characterized in that, With h = 30 mm, d = 10 mm.
7. The wound battery according to claim 2, characterized in that, The positive electrode tab (110) and the positive electrode sheet (100) of the integrated structure, as well as the negative electrode tab (210) and the negative electrode sheet (200) of the integrated structure, are all formed by die-cutting from the same sheet.
8. The wound battery according to claim 7, characterized in that, The die-cutting speed is 200mm / s-2000mm / s.
9. The wound battery according to any one of claims 1-8, characterized in that, On the formed wound battery, the positive tab (110) and the negative tab (210) are both located on the same side of the wound battery; All of the positive tabs (110) overlap in the thickness direction of the wound battery, and all of the negative tabs (210) overlap in the thickness direction of the wound battery.
10. The wound battery according to any one of claims 1-8, characterized in that, Both the positive electrode tab (110) and the positive electrode plate (100) are made of aluminum; Both the negative electrode tab (210) and the negative electrode sheet (200) are made of copper.