Winding battery
By setting up a group of electrodes with increasing and decreasing heights in the multi-layer structure of the roll core, the problem of the small stacking of electrodes and inability to weld during the welding process of the full-pole ear rolling battery is solved, and the battery rate performance is improved, reducing temperature rise and extending service life is achieved.
Patent Information
- Application Number
- CN202420240988.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-30
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2034-01-30
AI Technical Summary
During the welding process, the existing full-pole ear rolling batteries have problems such as few stacked electrodes and thin electrodes, which lead to the inability to weld, resulting in about 40% of the electrode plates and non-pole ears welding, uneven reaction, poor rate, insufficient overcurrent capacity, and high charge and discharge temperature rise.
By setting the first and second ear groups in the multi-layer structure of the roll core, the height of the ears in the first ear groups increases layer by layer from the inner layer to the outer layer, causing the inner layer to fall to the outer layer; the height of the ears in the second ear groups decreases layer by layer from the outer layer to the inner layer, causing the outer layer to fall to the inner layer to the inner layer to ensure uniform welding of the inner and outer layers.
Through uniform ear welding, the battery rate performance is improved, the temperature rise is reduced, the production efficiency is improved, the production cost is reduced, the battery internal resistance is significantly reduced, and the battery life is improved.
Smart Images
Figure CN222581197U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the field of battery technology, and in particular to a wound battery. Background Art
[0002] Full-ear winding batteries are increasingly being used due to their super high-rate discharge capability, stable high output voltage, and ultra-long working life. They are usually used in instrumentation, medical equipment, power transmission equipment, and automobiles. The positive and negative electrodes of full-ear winding batteries are all full-ear. After winding, the foil ears are flattened or turned inward, and then laser welded with the busbars. However, this method has fewer layers of inner ring ears and thin ears, which often make welding impossible. In the actual production process, about 40% of the pole pieces inside the full-ear winding battery have no pole ear welding, uneven reaction, and poor rate performance. The number of effective welded ears is less than one-fifth of the entire length of the pole piece, and the welding effect is poor, resulting in insufficient actual overcurrent capacity and high temperature rise during high current charging and discharging. Utility Model Content
[0003] The present disclosure provides a wound battery to at least solve the above technical problems existing in the prior art.
[0004] According to the present disclosure, there is provided a wound battery, comprising a winding core, wherein the winding core is a multilayer structure formed by winding a pole piece and a separator along a winding direction after being compounded, the pole piece comprising a coating area and a pole lug connected to the coating area, the pole piece having a winding state and an unfolded state, the pole lug forming a first pole lug group and a second pole lug group when the pole piece is in the winding state, the pole lugs in the first pole lug group being pushed and arranged from the innermost layer of the winding core to the outermost layer, and the pole lugs in the second pole lug group being pushed and arranged from the outermost layer of the winding core to the innermost layer; wherein the distance between one side of the pole lug away from the coating area and the coating area is defined as the height of the pole lug, and in the first pole lug group, the height of the pole lug increases layer by layer from the outermost layer to the innermost layer of the winding core; and in the second pole lug group, the height of the pole lug decreases layer by layer from the outermost layer to the innermost layer of the winding core.
[0005] In one embodiment, the end surface of the winding core is divided into a first semicircular area and a second semicircular area, the first pole lug group is located in the first semicircular area, the second pole lug group is located in the second semicircular area, and the first pole lug group and the second pole lug group are connected.
[0006] In one possible implementation manner, the pole lugs in the first pole lug group are defined as first pole lugs, and the pole lugs in the second pole lug group are defined as second pole lugs. When the pole piece is in an expanded state, a plurality of the first pole lugs are spaced apart to form a gap between two adjacent first pole lugs, and a plurality of the second pole lugs are disposed in the gap in a one-to-one correspondence.
[0007] In one possible implementation manner, when the pole piece is in an unfolded state, in the winding direction, the height of the first pole lug decreases gradually, and the height of the second pole lug increases gradually.
[0008] In one possible implementation manner, when the pole piece is in an unfolded state, in the winding direction, the length of the first pole lug increases gradually, and the length of the second pole lug increases gradually.
[0009] In one embodiment, the number of the first electrode tabs is the same as the number of the second electrode tabs.
[0010] In one embodiment, when the pole piece is in a wound state, the first pole lug and the second pole lug in any layer of the multilayer structure have the same length, and the sum of the lengths of the first pole lug and the second pole lug is the circumference of the layer.
[0011] In one possible implementation manner, the electrode sheets include a positive electrode sheet and a negative electrode sheet, the electrode tabs include a positive electrode tab and a negative electrode tab, the positive electrode tab is connected to the coating area of the positive electrode sheet, the negative electrode tab is connected to the coating area of the negative electrode sheet, and the winding core is wound by sequentially combining the diaphragm, the positive electrode sheet, the diaphragm and the negative electrode sheet.
[0012] In one possible implementation manner, the positive electrode sheet and the negative electrode sheet are placed in opposite directions, so that the positive electrode tab and the negative electrode tab are respectively arranged at two ends of the winding core.
[0013] In one embodiment, a busbar is further included, and the busbar is welded to the tab.
[0014] In the present disclosure, since the height of the pole lugs in the first pole lug group decreases layer by layer from the inner layer to the outer layer, the inner pole lugs are inverted to the outer pole lugs, and the height of the pole lugs in the group decreases layer by layer from the outer layer to the inner layer, so that the outer pole lugs are inverted to the inner pole lugs, thereby ensuring that the inner layer of the winding core has pole lug welding and the inner and outer pole lugs are welded evenly, the pole piece cross-section reacts evenly, and the polarization is effectively reduced; the welding area of the pole lug is expanded, the number of effective pole lug welding is increased, and the welding short circuit rate is reduced, which can not only improve the rate performance of the battery and reduce the temperature rise, but also improve the production efficiency and reduce the production cost; in addition, the length of the effective welded pole lug is increased, which can significantly reduce the internal resistance of the battery, improve the consistency of the battery pressure difference, and increase the service life of the battery.
[0015] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present disclosure are shown in an exemplary and non-limiting manner, in which:
[0017] In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.
[0018] Figure 1 The overall structure schematic diagram of a wound battery according to an exemplary embodiment of the present disclosure is shown;
[0019] Figure 2 A schematic diagram showing an unfolded state of a pole piece of a wound battery according to an exemplary embodiment of the present disclosure is shown.
[0020] Explanation of the numbers in the figure: 1, pole piece; 3, winding core; 11, first pole ear; 12, second pole ear; 13, coating area; 21, first pole ear group; 22, second pole ear group; 101, initial end; 102, terminal end. DETAILED DESCRIPTION
[0021] In order to make the purpose, features, and advantages of the present disclosure more obvious and easy to understand, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present disclosure.
[0022] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.
[0023] Reference Figure 1 and Figure 2As shown, a wound battery according to an embodiment of the present disclosure includes a winding core 3, which is a multi-layer structure formed by winding a pole piece 1 and a separator in a winding direction, and the pole piece 1 includes a coating area 13 and a pole lug connected to the coating area 13, and the pole piece 1 has a winding state and an unfolded state. When the pole piece 1 is in the winding state, the pole lug forms a first pole lug group 21 and a second pole lug group 22, and the pole lugs in the first pole lug group 21 are pushed from the innermost layer to the outermost layer of the winding core 3, and the pole lugs in the second pole lug group 22 are pushed from the outermost layer to the innermost layer of the winding core 3. The distance between the side of the pole lug away from the coating area 13 and the coating area 13 is defined as the height of the pole lug. In the first pole lug group 21, the height of the pole lug increases layer by layer from the outermost layer to the innermost layer of the winding core 3, and in the second pole lug group 22, the height of the pole lug decreases layer by layer from the outermost layer to the innermost layer of the winding core 3.
[0024] In this embodiment, the coating area 13 can be an aluminum foil layer or a copper foil layer, that is, the coating area 13 can be coated with aluminum foil or copper foil. Since the height of the pole lugs in the first pole lug group 21 increases layer by layer from the outermost layer to the innermost layer of the winding core 3 when the pole piece 1 is in the wound state, and the height of the pole lugs in the second pole lug group 22 decreases layer by layer from the outermost layer to the innermost layer of the winding core 3, when the pole piece 1 is in the unfolded state, the heights of the two adjacent pole lugs are different. Therefore, when forming the pole lugs, the empty foil area at the edge of the pole piece 1 can be laser cut according to actual needs to form the pole lugs in the present disclosure. After the pole lugs in the first pole lug group 21 and the second pole lug group 22 are pushed and set, they can be bent or flattened for subsequent welding with the busbar, thereby reducing the risk of short circuit. Since the height of the pole lugs in the first pole lug group 21 decreases layer by layer from the inner layer to the outer layer, the inner pole lugs are inverted to the outer pole lugs, and the height of the pole lugs in the group decreases layer by layer from the outer layer to the inner layer, so that the outer pole lugs are inverted to the inner pole lugs, thereby ensuring that the inner layer of the winding core 3 has pole lug welding and the inner and outer pole lugs are welded evenly, the cross-section of the pole piece 1 reacts evenly, and the polarization is effectively reduced; the welding area of the pole lug is expanded, the number of effective pole lug welding increases, and the welding short circuit rate is reduced, which can not only improve the rate performance of the battery and reduce the temperature rise, but also improve the production efficiency and reduce the production cost; in addition, the length of the effective welded pole lug is increased, which can significantly reduce the internal resistance of the battery, improve the consistency of the battery pressure difference, and increase the service life of the battery.
[0025] In one embodiment, the end surface of the winding core 3 is divided into a first semicircular area and a second semicircular area. The first tab group 21 is located in the first semicircular area, the second tab group 22 is located in the second semicircular area, and the first tab group 21 and the second tab group 22 are connected.
[0026] In this embodiment, the first electrode tab group 21 and the second electrode tab group 22 are respectively arranged to occupy half of the end surface of the winding core 3 , which can increase the stability of welding and reduce the welding short circuit rate.
[0027] In one embodiment, the pole lugs in the first pole lug group 21 are defined as first pole lugs 11, and the pole lugs in the second pole lug group 22 are defined as second pole lugs 12. When the pole piece 1 is in an expanded state, the plurality of first pole lugs 11 are arranged at intervals, and a gap is formed between two adjacent first pole lugs 11. The plurality of second pole lugs 12 are arranged one by one in the gap formed between each two adjacent first pole lugs 11.
[0028] Specifically, in one embodiment, when the pole piece 1 is in the unfolded state, in the winding direction, the height of the first pole lug 11 decreases, and the height of the second pole lug 12 increases. When the pole piece 1 is in the unfolded state, in the winding direction, the length of the first pole lug 11 increases, and the length of the second pole lug 12 increases.
[0029] In one embodiment, the number of the first electrode tabs 11 is the same as the number of the second electrode tabs 12 .
[0030] In this embodiment, the pole piece 1 is defined to have an initial end 101 and a terminal end 102 when wound, the initial end 101 is located at the innermost layer of the winding core 3, and the terminal end 102 is located at the outermost layer of the winding core 3. The pole tabs are sequentially the first pole tab 11, the second pole tab 12, the first pole tab 11, the second pole tab 12... the second pole tab 12, the first pole tab 11, the second pole tab 12, and the terminal end 102 starting from the initial end 101 of the pole piece 1. The first pole tab 11 and the second pole tab 12 are arranged in pairs starting from the initial end 101 to form a plurality of pole tab pairs, and the first pole tab 11 and the second pole tab 12 in each pole tab pair are located in the same layer of the multi-layer structure formed after winding, so the first pole tab 11 and the second pole tab 12 in each pole tab pair have the same length.
[0031] In one embodiment, when the pole piece 1 is in a wound state, the lengths of the first pole tab 11 and the second pole tab 12 in any layer of the multilayer structure are the same, and the sum of the lengths of the first pole tab 11 and the second pole tab 12 is the circumference of the layer.
[0032] In one embodiment, the electrode sheet 1 includes a positive electrode sheet and a negative electrode sheet, the electrode tab includes a positive electrode tab and a negative electrode tab, the positive electrode tab is connected to the coating area 13 of the positive electrode sheet, and the negative electrode tab is connected to the coating area 13 of the negative electrode sheet. The winding core 3 is wound by sequentially combining the diaphragm, the positive electrode sheet, the diaphragm and the negative electrode sheet.
[0033] In this embodiment, the winding core 3 is wound after being compounded with a separator, a positive electrode sheet, a separator and a negative electrode sheet in sequence. After winding, the negative electrode sheet is located at the outermost layer of the winding core 3, and the separator is located at the innermost layer of the winding core 3.
[0034] Furthermore, in one embodiment, the positive electrode sheet and the negative electrode sheet are placed in opposite directions, so that the positive electrode tab and the negative electrode tab are respectively arranged at two ends of the winding core 3.
[0035] In this embodiment, when the positive electrode ear and the negative electrode ear are respectively arranged at the two ends of the winding core 3, the wound battery is a high-rate system battery. Therefore, the DC internal resistance of the high-rate system battery can be effectively reduced and the service life of the battery can be improved. Since the number of effective welded electrode ears of the battery is increased, the current flow capacity is improved, the heat generation is reduced, and the cycle performance is improved.
[0036] In one possible implementation manner, the wound battery further includes a busbar, and the busbar is welded to the tab.
[0037] In this embodiment, after the first tab group 21 and the second tab group 22 are pushed and arranged, they can be bent, flattened or ultrasonically welded, and then laser welded with the busbar, thereby reducing the risk of short circuit and improving the tab welding rate.
[0038] In the description of the present disclosure, it is necessary to understand that the orientation or positional relationship indicated by the directional words is usually based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present disclosure; the directional words "inside" and "outside" refer to the inside and outside relative to the outline of each component itself.
[0039] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between one or more components or features shown in the figure and other components or features. It should be understood that spatially relative terms include not only the orientation of the components as described in the figure, but also different orientations in use or operation. For example, if the components in the accompanying drawings are inverted as a whole, the components "above other components or features" or "above other components or features" will include the situation where the components are "below other components or structures" or "below other components or structures". Therefore, the exemplary term "above" may include both "above" and "below". In addition, these components or features may also be positioned at other different angles (e.g., rotated 90 degrees or other angles), and this article is intended to include all of these situations.
[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, parts, components and / or combinations thereof.
[0041] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein.
[0042] The present disclosure has been described through the above-mentioned embodiments, but it should be understood that the above-mentioned embodiments are only for the purpose of example and description, and are not intended to limit the present disclosure to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present disclosure is not limited to the above-mentioned embodiments, and more variations and modifications can be made according to the teachings of the present disclosure, and these variations and modifications all fall within the scope of protection claimed by the present disclosure. The scope of protection of the present disclosure is defined by the attached claims and their equivalents.
Claims
1. A wound battery, comprising a winding core (3), wherein the winding core (3) is a multilayer structure formed by winding a pole piece (1) and a separator in a winding direction, wherein the pole piece (1) comprises a coating area (13) and a pole ear connected to the coating area (13), and the pole piece (1) has a wound state and an unfolded state, and is characterized in that: The pole lugs form a first pole lug group (21) and a second pole lug group (22) when the pole piece (1) is in a wound state. The pole lugs in the first pole lug group (21) are pushed from the innermost layer to the outermost layer of the winding core (3), and the pole lugs in the second pole lug group (22) are pushed from the outermost layer to the innermost layer of the winding core (3); wherein the distance between the side of the pole lug away from the coating area (13) and the coating area (13) is defined as the height of the pole lug. In the first pole lug group (21), the height of the pole lug increases layer by layer from the outermost layer to the innermost layer of the winding core (3); and in the second pole lug group (22), the height of the pole lug decreases layer by layer from the outermost layer to the innermost layer of the winding core (3).
2. The wound battery according to claim 1, characterized in that: The end surface of the winding core (3) is divided into a first semicircular area and a second semicircular area, the first pole lug group (21) is located in the first semicircular area, the second pole lug group (22) is located in the second semicircular area, and the first pole lug group (21) and the second pole lug group (22) are connected.
3. The wound battery according to claim 1, characterized in that: The pole lugs in the first pole lug group (21) are defined as first pole lugs (11), and the pole lugs in the second pole lug group (22) are defined as second pole lugs (12). When the pole piece (1) is in an unfolded state, a plurality of the first pole lugs (11) are arranged at intervals, a gap is formed between two adjacent first pole lugs (11), and a plurality of the second pole lugs (12) are arranged in the gap in a one-to-one correspondence.
4. The wound battery according to claim 3, characterized in that: When the pole piece (1) is in an unfolded state, in the winding direction, the height of the first pole lug (11) decreases gradually, while the height of the second pole lug (12) increases gradually.
5. The wound battery according to claim 3, characterized in that: When the pole piece (1) is in an unfolded state, in the winding direction, the length of the first pole lug (11) increases gradually, and the length of the second pole lug (12) increases gradually.
6. The wound battery according to claim 3, characterized in that: The number of the first pole tabs (11) is the same as the number of the second pole tabs (12).
7. The wound battery according to claim 3, characterized in that: When the pole piece (1) is in a wound state, the first pole lug (11) and the second pole lug (12) located in any layer of the multilayer structure have the same length, and the sum of the lengths of the first pole lug (11) and the second pole lug (12) is the circumference of the layer.
8. The wound battery according to claim 1, characterized in that: The electrode sheet (1) comprises a positive electrode sheet and a negative electrode sheet, the electrode tab comprises a positive electrode tab and a negative electrode tab, the positive electrode tab is connected to the coating area (13) of the positive electrode sheet, the negative electrode tab is connected to the coating area (13) of the negative electrode sheet, and the winding core (3) is wound by sequentially combining the separator, the positive electrode sheet, the separator and the negative electrode sheet.
9. The wound battery according to claim 8, characterized in that: The positive electrode sheet and the negative electrode sheet are placed in opposite directions, so that the positive electrode tab and the negative electrode tab are respectively arranged at two ends of the winding core (3).
10. The wound battery according to claim 1, characterized in that: It also includes a busbar, which is welded to the tab.