Pole piece, pole core, battery and vehicle
By designing the electrode sheets that extend along two adjacent sides of the body, the problem of excessive temperature caused by the small overcurrent area of the electrode is solved, and the effect of reducing the current density and temperature is achieved, and the risk of short circuit of the positive and negative electrodes is avoided.
Patent Information
- Application Number
- CN202421755646.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-23
- Publication Date
- 2025-05-30
- Estimated Expiration
- 2034-07-23
AI Technical Summary
In the prior art, the length and size of the electrode ear are small, resulting in a smaller overcurrent area and a larger current density, which can easily lead to excessive temperature of the electrode ear, which can lead to a risk of short circuit of the positive and negative electrodes.
A pole piece is designed, with the pole ear extending along two adjacent sides of the body, increasing the overcurrent area of the pole ear, dispersing or reducing the current density, thereby reducing the risk of local temperature of the pole ear.
By increasing the overcurrent area of the pole ear, the current density and local temperature of the pole ear are reduced, the risk of short circuit of the positive and negative electrodes is effectively avoided, and the safety and performance of the battery are improved.
Smart Images
Figure CN222927518U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, and particularly to a pole piece, a pole core, a battery and a vehicle. Background Art
[0002] As an important component of a battery, the quality of the pole piece directly affects the performance of the battery. The pole piece generally includes a current collector and an active layer disposed on the surface of the current collector. Among them, a blank area that is not coated with the active layer is usually reserved on one side of the current collector as a tab, and the tab is used to connect to a pole column and allow current to flow through.
[0003] Assuming that the dimension of the tab along the edge direction of the active layer is the length dimension of the tab, the length dimension of the tab in the prior art is usually small, resulting in a small current-carrying area of the tab and a large current density carried. Therefore, when the charging current or the discharging current increases, the tab is likely to have an over-high temperature. The over-high temperature of the tab will cause local thermal shrinkage of the separator between the positive electrode sheet and the negative electrode sheet, and there is a risk of short circuit between the positive and negative electrodes. Summary of the Utility Model
[0004] In view of this, the utility model provides a pole piece, a pole core, a battery and a vehicle to solve or improve the problem that the length dimension of the tab in the prior art is usually small, resulting in a small current-carrying area of the tab.
[0005] In a first aspect, the utility model provides a pole piece, comprising:
[0006] A body part, comprising a current collector and an active layer disposed on the surface of the current collector, the body part having adjacent first and second sides;
[0007] A first tab and a second tab, the first tab is disposed on the first side of the body part and connected to the current collector, the second tab is disposed on the second side of the body part and connected to the current collector, and the first tab and the second tab are connected.
[0008] Advantageous Effects: The first tab extends along the first side, and the second tab extends along the second side. Compared with the tab in the prior art, the tab in the embodiment of the utility model extends along two adjacent sides of the body part, so the extension length is longer, thereby increasing the current-carrying area of the tab, dispersing or reducing the current density of the tab, and further reducing the risk of over-high local temperature of the tab.
[0009] In an optional embodiment, both the current collector and the active layer are rectangular structures, and the length and width of the current collector are respectively greater than the length and width of the active layer;
[0010] One pair of adjacent long sides and wide sides of the current collector are flush with one pair of adjacent long sides and wide sides of the active layer respectively. The overlapping part of the current collector and the active layer together constitutes the body part. The part of the current collector protruding from the first side of the body part constitutes the first pole ear part, and the part protruding from the second side of the body part constitutes the second pole ear part.
[0011] In a second aspect, the present invention provides a pole core, including a positive electrode sheet, a negative electrode sheet, and a separator. At least one of the positive electrode sheet and the negative electrode sheet is configured as the electrode sheet described above, and the separator is disposed between the active layer of the positive electrode sheet and the active layer of the negative electrode sheet.
[0012] In an optional embodiment, the area of the active layer of the negative electrode sheet is larger than the area of the active layer of the positive electrode sheet.
[0013] In an optional embodiment, the positive electrode sheets and the negative electrode sheets are arranged alternately, and the separator is disposed between adjacent positive electrode sheets and negative electrode sheets;
[0014] Wherein, the first pole ear parts of the positive electrode sheet are connected to each other, and / or, the second pole ear parts of the positive electrode sheet are connected to each other;
[0015] The first pole ear parts of the negative electrode sheet are connected to each other, and / or, the second pole ear parts of the negative electrode sheet are connected to each other.
[0016] In an optional embodiment, it further includes a first connection structure and a second connection structure. The first pole ear parts are connected by the first connection structure, and the second pole ear parts are connected by the second connection structure. The first connection structure extends along the first side, and the second connection structure extends along the second side.
[0017] In an optional embodiment, the connection area between the first pole ear parts extends along the first side of the body part.
[0018] In an optional embodiment, the connection area between the second pole ear parts extends along the second side of the body part.
[0019] In an optional embodiment, the first pole ear parts and / or the second pole ear parts are bonded, welded or riveted with conductive adhesive.
[0020] In a third aspect, the present invention further provides a battery, including the electrode sheet described above, or including the pole core described above.
[0021] Beneficial effects: The battery includes the electrode sheet, and thus includes all the above-mentioned advantages of the electrode sheet. Similarly, if the battery includes the battery cell, it also includes all the above-mentioned advantages of the battery cell, so this will not be elaborated herein.
[0022] In a fourth aspect, the present utility model further provides a vehicle, including the battery as described above.
[0023] Beneficial effects: The vehicle includes the battery, and thus includes all the above-mentioned advantages of the battery, so this will not be elaborated herein. Description of the Drawings
[0024] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0025] Figure 1 It is a schematic structural diagram of an electrode sheet according to an embodiment of the present utility model;
[0026] Figure 2 It is Figure 1 the C-C cross-sectional view in
[0027] Figure 3 It is Figure 1 the D-D cross-sectional view in
[0028] Figure 4 It is a schematic structural diagram of a pole core according to an embodiment of the present utility model;
[0029] Figure 5 It is a schematic structural diagram of another pole core according to an embodiment of the present utility model;
[0030] Figure 6 It is an exploded schematic diagram of a pole core according to an embodiment of the present utility model.
[0031] Explanation of the reference numerals:
[0032] 1, body part; 101, current collector; 102, active layer; 103, first side; 104, second side; 2, first pole ear; 3, second pole ear; 4, connection area; 5, separator. Specific Embodiments
[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.
[0034] In the prior art, the length dimension of the tab is usually small, resulting in a small current-carrying area of the tab, while the current density carried is large. During fast charging, more heat accumulates in the tab and the temperature rises more significantly. For example, during 3C charging, the highest temperature of the tab is about 43°C, while the highest temperature of the large surface of the battery is about 33°C. The too high temperature of the tab easily causes local thermal shrinkage of the separator 5 between the positive electrode sheet and the negative electrode sheet, posing a risk of short circuit between the positive and negative electrodes.
[0035] To solve or improve the technical problem that in the prior art, the length dimension of the tab is usually small, resulting in a small current-carrying area of the tab, while the current density carried is large, the embodiments of the present utility model provide a pole piece, a pole core, a battery, and a vehicle.
[0036] The following combines Figures 1 to 6 , and describes the pole piece in the embodiments of the present utility model.
[0037] Specifically, the pole piece includes a body portion 1, a first tab portion 2, and a second tab portion 3.
[0038] Among them, the body portion 1 includes a current collector 101 and an active layer 102 provided on the surface of the current collector 101. The body portion 1 has an adjacent first side 103 and a second side 104. Among them, the current collector 101 is provided as a metal foil. Optionally, when the pole piece is used as a negative electrode piece, the current collector 101 can be provided as a copper foil; when the pole piece is used as a positive electrode piece, the current collector 101 can be provided as an aluminum foil. Optionally, the active layer 102 can be formed by an active material coated on the surface of the current collector 101. The active materials of the positive electrode piece and the negative electrode piece are different, and the selection of the active materials of the positive electrode piece and the negative electrode piece belongs to the content well-known to those skilled in the art and is not the focus of the discussion in this article, so it will not be elaborated here.
[0039] The first tab portion 2 is provided on the first side 103 of the body, and the first tab portion 2 is connected to the current collector 101. The second tab portion 3 is provided on the second side 104 of the body, and the second tab portion 3 is connected to the current collector 101. The first tab portion 2 and the second tab portion 3 are connected.
[0040] In this embodiment, during the use of the electrode tab, the first electrode ear 2 and the second electrode ear 3 can transmit current simultaneously, so that the current is dispersed on the first electrode ear 2 and the second electrode ear 3.
[0041] In the prior art, the electrode ear is provided on one side of the current collector 101, that is, it only extends along the edge of one side of the current collector 101, and the extension length is short. In this application, the first electrode ear 2 is arranged along the first side 103, and the second electrode ear 3 is arranged along the second side 104. Compared with the electrode ear in the prior art, the electrode ear in the embodiment of the present invention is arranged along two adjacent sides of the body part 1, so the extension length is longer, thereby increasing the current-carrying area of the electrode ear, dispersing or reducing the current density of the electrode ear, and further reducing the risk of excessive local temperature of the electrode ear.
[0042] Reference Figure 1 As shown, in some embodiments provided by the present invention, both the current collector 101 and the active layer 102 are rectangular structures, and the length and width of the current collector 101 are respectively greater than the length and width of the active layer 102. For example, as shown in Figure 1 As shown, the length of the current collector 101 refers to the dimension of the current collector 101 in the a direction in the figure, and the width of the current collector 101 refers to the dimension of the current collector 101 in the b direction in the figure.
[0043] A pair of adjacent long sides and wide sides of the current collector 101 are respectively flush with a pair of adjacent long sides and wide sides of the active layer 102, and the overlapping part of the current collector 101 and the active layer 102 together constitutes the body part 1. The part of the current collector 101 protruding from the first side 103 of the body part 1 constitutes the first electrode ear 2, and the part of the current collector 101 protruding from the second side 104 of the body part 1 constitutes the second electrode ear 3.
[0044] In this embodiment, by setting both the current collector 101 and the active layer 102 as rectangular structures, it is convenient to process with existing manufacturing equipment. And by aligning two adjacent side edges of the active layer 102 with two adjacent side edges of the current collector 101 respectively, the other two side edges of the current collector 101 naturally protrude from the other two side edges of the active layer 102, thus forming electrode ears. In this way, the structure of the electrode tab can be simplified and the processing difficulty of the electrode tab can be reduced.
[0045] In some embodiments provided by the present invention, active layers 102 are provided on both surfaces of the current collector 101, and the projections of the active layers 102 on both sides of the current collector 101 coincide. In this embodiment, by providing active layers 102 on both surfaces of the current collector 101, when the electrode tab is used as a positive electrode tab, negative electrode tabs can be provided on both sides of it, or when the electrode tab is used as a negative electrode tab, positive electrode tabs can be provided on both sides of it, so as to make full use of the available space of the battery and improve the performance and energy density of the battery.
[0046] In an alternative embodiment, the difference between the length of the current collector 101 and the length of the active layer 102 is greater than or equal to 0.2 cm.
[0047] In an alternative embodiment, the difference between the width of the current collector 101 and the width of the active layer 102 is greater than or equal to 0.2 cm.
[0048] An electrode core is also provided in an embodiment of the present utility model.
[0049] Specifically, the electrode core includes a positive electrode plate, a negative electrode plate, and a separator 5. At least one of the positive electrode plate and the negative electrode plate is configured as the electrode plate described above. The separator 5 is disposed between the active layer 102 of the positive electrode plate and the active layer 102 of the negative electrode plate.
[0050] It can be understood that when the electrode plate is used as the positive electrode plate, the current collector 101 and the active layer 102 of the electrode plate are configured as the positive current collector 101 and the positive active layer 102; when the electrode plate is used as the negative electrode plate, the current collector 101 and the active layer of the electrode plate are configured as the negative current collector 101 and the negative active layer 102. The related content of the positive current collector 101, the positive active layer 102, the negative current collector 101, and the negative active layer 102 belongs to the prior art and is not the focus of the discussion in this article, so it will not be elaborated here.
[0051] It should be noted that the electrode core includes the electrode plate described above, so it simultaneously includes all the above advantages of the electrode plate, so it will not be elaborated here.
[0052] In some embodiments provided by the present utility model, the positive electrode plates and the negative electrode plates are alternately arranged in sequence, and a separator 5 is disposed between adjacent positive electrode plates and negative electrode plates. For example, the number of both the positive electrode plates and the negative electrode plates is set to at least two.
[0053] Among them, the first pole ears 2 of the positive electrode plates are connected to each other, and / or the second pole ears 3 of the positive electrode plates are connected to each other.
[0054] The first pole ears 2 of the negative electrode plates are connected to each other, and / or the second pole ears 3 of the negative electrode plates are connected to each other.
[0055] In this embodiment, by providing a plurality of positive electrode plates and negative electrode plates, and connecting the pole ears of all the positive electrode plates to form a parallel structure, and connecting the pole ears of all the negative electrode plates to form a parallel structure, the total internal resistance of the battery can be effectively reduced, the energy efficiency can be improved, and a larger current can be allowed to pass, so that the battery supports a higher discharge rate. In addition, the compactness of the battery can also be improved, so as to achieve a higher energy density in a limited space.
[0056] Reference Figure 4 and Figure 5As shown, in some embodiments provided by the present utility model, the connection region 4 between the first pole lugs 2 extends along the first side 103 of the body portion 1.
[0057] Since the first pole lugs 2 are arranged along the first side 103 of the body portion 1, in this embodiment, by arranging the connection region 4 between the first pole lugs 2 to extend along the first side 103 of the body portion 1, on the one hand, the connection strength between the first pole lugs 2 can be improved, so that a firm connection is formed between the first pole lugs 2; on the other hand, the contact range between the first pole lugs 2 can be increased, ensuring the conductive effect between the first pole lugs 2.
[0058] Reference Figure 4 and Figure 5 As shown, in some embodiments provided by the present utility model, the connection region 4 between the second pole lugs 3 extends along the second side 104 of the body portion 1.
[0059] Since the second pole lugs 3 are arranged along the second side 104 of the body portion 1, in this embodiment, by arranging the connection region 4 between the second pole lugs 3 to extend along the second side 104 of the body portion 1, on the one hand, the connection strength between the second pole lugs 3 can be improved, so that a firm connection is formed between the second pole lugs 3; on the other hand, the contact range between the second pole lugs 3 can be increased, ensuring the conductive effect between the second pole lugs 3.
[0060] In some embodiments provided by the present utility model, the first pole lugs 2 and / or the second pole lugs 3 are adhesively bonded with conductive adhesive. By adhesively bonding the first pole lugs 2 or the second pole lugs 3 with conductive adhesive, loosening caused by mechanical vibration can be prevented, and the conductive adhesive can increase the contact surface between the first pole lugs 2 or the second pole lugs 3, thereby effectively reducing the resistance.
[0061] Of course, the first pole lugs 2 and / or the second pole lugs 3 can also be welded. By welding the first pole lugs 2 or the second pole lugs 3, the connection strength between the first pole lugs 2 or the second pole lugs 3 can be improved, and the anti-vibration ability and anti-impact ability between the first pole lugs 2 or the second pole lugs 3 can be enhanced.
[0062] Of course, the first pole lugs 2 and / or the second pole lugs 3 can also be riveted. By riveting the first pole lugs 2 or the second pole lugs 3, the processing speed is faster and it is easy to realize automation, thereby improving the production efficiency of the battery. In addition, the consistency and repeatability of each riveting point are relatively high, making the connection quality of each part more consistent. Moreover, riveting is not likely to have an impact on or damage the surrounding area.
[0063] Reference Figure 4As shown, optionally, the connection area 4 is set as a continuous structure, thereby improving the connection strength of the tab. Or, refer to Figure 5 As shown, optionally, the connection area 4 is set as an intermittent structure, thereby simplifying the structure of the connection structure and reducing the cost of the battery.
[0064] In some embodiments provided by the present utility model, the area of the active layer 102 of the negative electrode sheet is larger than the area of the active layer 102 of the positive electrode sheet. Since during the charging process, lithium ions move from the positive electrode sheet to the negative electrode sheet, by making the area of the active layer 102 of the negative electrode sheet larger than the area of the active layer 102 of the positive electrode sheet, the receiving area of the active layer 102 of the negative electrode sheet can be increased, so that all the lithium ions released by the positive electrode sheet can be received by the negative electrode sheet, reducing the problem of lithium deposition in the battery.
[0065] Refer to Figure 4 and Figure 5 As shown, in some embodiments provided by the present utility model, the first tab portions 2 of the positive electrode sheet and the first tab portions 2 of the negative electrode sheet are distributed along a first direction and are respectively arranged on both sides of the electrode core. The second tab portions 3 of the positive electrode sheet and the second tab portions 3 of the negative electrode sheet are distributed along a second direction and are respectively arranged at both ends of the electrode core. The first direction and the second direction intersect, for example, they are perpendicular to each other. For example, refer to Figure 4 and Figure 5 As shown, the first direction is the a direction in the figure, and the second direction is the b direction in the figure.
[0066] In this embodiment, by respectively arranging the first tab portions 2 of the positive electrode sheet and the first tab portions 2 of the negative electrode sheet on both sides of the electrode core, the problem that the first tab portions 2 of the positive electrode sheet and the first tab portions 2 of the negative electrode sheet come into contact and cause a short circuit can be avoided. Similarly, by respectively arranging the second tab portions 3 of the positive electrode sheet and the second tab portions 3 of the negative electrode sheet at both ends of the electrode core, the problem that the second tab portions 3 of the positive electrode sheet and the second tab portions 3 of the negative electrode sheet come into contact and cause a short circuit can be avoided. Furthermore, the tab portions of the positive electrode sheet and the tab portions of the negative electrode sheet can not only make full use of the space inside the battery, but also have sufficient extension length, and the tab portions of the positive and negative electrodes will not come into contact and cause a short circuit problem.
[0067] In the embodiments of the present utility model, a battery is also provided.
[0068] Specifically, the battery includes the electrode sheets as described above. Or, the battery includes the electrode core as described above.
[0069] It should be noted that since the battery includes the electrode sheets, it also includes all the above advantages of the electrode sheets. Similarly, if the battery includes the electrode core, it also includes all the above advantages of the electrode core, so this will not be elaborated here.
[0070] In the embodiments of the present utility model, a vehicle is also provided.
[0071] Specifically, the vehicle includes the battery as described above.
[0072] It should be noted that since the vehicle includes the battery, it also includes all the above-mentioned advantages of the battery, so no further elaboration will be made here.
[0073] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.
Claims
1. A pole piece, characterized in that: include: A main body (1) comprising a current collector (101) and an active layer (102) disposed on the surface of the current collector (101), wherein the main body (1) has a first side (103) and a second side (104) adjacent to each other; A first pole ear portion (2) and a second pole ear portion (3), wherein the first pole ear portion (2) is arranged on a first side (103) of the main body portion (1) and is connected to the current collector (101), and the second pole ear portion (3) is arranged on a second side (104) of the main body portion (1) and is connected to the current collector (101), and the first pole ear portion (2) and the second pole ear portion (3) are connected.
2. The pole piece according to claim 1, characterized in that: The current collector (101) and the active layer (102) are both rectangular structures, and the length and width of the current collector (101) are respectively greater than the length and width of the active layer (102); A pair of adjacent long sides and wide sides of the current collector (101) are respectively flush with a pair of adjacent long sides and wide sides of the active layer (102); the overlapping portions of the current collector (101) and the active layer (102) together constitute the main body (1); the portion of the current collector (101) protruding from the first side (103) of the main body (1) constitutes the first pole ear portion (2); and the portion of the current collector (101) protruding from the second side (104) of the main body (1) constitutes the second pole ear portion (3).
3. A pole core, characterized in that: The invention comprises a positive electrode sheet, a negative electrode sheet and a separator (5), wherein at least one of the positive electrode sheet and the negative electrode sheet is configured as the electrode sheet as claimed in any one of claims 1 to 2, and the separator (5) is configured between the active layer (102) of the positive electrode sheet and the active layer (102) of the negative electrode sheet.
4. The pole core according to claim 3, characterized in that: The area of the active layer (102) of the negative electrode sheet is greater than the area of the active layer (102) of the positive electrode sheet.
5. The pole core according to claim 3, characterized in that: The positive electrode sheets and the negative electrode sheets are arranged alternately, and the separator (5) is arranged between adjacent positive electrode sheets and negative electrode sheets; wherein, The first electrode lugs (2) of the positive electrode sheets are connected to each other, and / or the second electrode lugs (3) of the positive electrode sheets are connected to each other; The first electrode lug portions (2) of the negative electrode sheets are connected to each other, and / or the second electrode lug portions (3) of the negative electrode sheets are connected to each other.
6. The pole core according to claim 5, characterized in that: The connection area (4) between the first pole lug portions (2) is arranged to extend along the first edge (103) of the main body portion (1).
7. The pole core according to claim 5, characterized in that: The connection area (4) between the second pole lug portions (3) is arranged to extend along the second edge (104) of the main body portion (1).
8. The pole core according to claim 5, characterized in that: The first pole lug portions (2) and / or the second pole lug portions (3) are bonded, welded or riveted with conductive adhesive.
9. A battery, characterized in that: It comprises a pole piece as described in any one of claims 1 to 2, or it comprises a pole core as described in any one of claims 3 to 8.
10. A vehicle, characterized in that: Comprising the battery as claimed in claim 9.