Pole piece, battery core pole group and battery core

Abstract

The utility model relates to the technical field of batteries, and discloses a pole piece, a battery core pole group and a battery core. The pole piece comprises a pole piece body, one side of the pole piece body is provided with a pair of notches, a protruding part is formed between the pair of notches, and the protruding part is suitable for being matched with the lower surface of a battery cell cover plate; and the tab is at least partially positioned in one of the notches and is connected with the pole piece body. According to the utility model, the lug boss matched with the lower surface of the battery cell cover plate is arranged on the pole piece body, so that a gap between the battery cell cover plate and the pole piece body can be effectively filled, and the space utilization rate in the battery cell is improved; meanwhile, the volume of a battery cell pole group formed by the pole piece can be increased, and the energy density of a battery cell formed by the battery cell pole group is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to an electrode sheet, a cell electrode assembly, and a cell. Background Technology

[0002] A battery cell is a device that can both store and release electrical energy. It generally consists of a cover, a housing, and an array of electrodes housed within the housing. To ensure smooth current flow through the cell, the terminals on the cover are electrically connected to the tabs on the electrode array. Furthermore, to improve the ease of connection between the terminals and tabs, the tabs are usually higher than the surface of the electrode array. This creates a gap between the cover and the electrode array surface, which in turn affects the utilization of the cell's internal space. Utility Model Content

[0003] In view of this, the present invention provides an electrode sheet, a cell electrode assembly, and a cell to solve the problem of low internal space utilization of the cell.

[0004] In a first aspect, this utility model provides an electrode sheet, comprising:

[0005] The electrode body has a pair of notches on one side, and a protrusion is formed between the pair of notches. The protrusion is adapted to mate with the lower surface of the cell cover plate.

[0006] The tab is at least partially located within one of the notches and connected to the electrode body.

[0007] Beneficial Effects: This invention, by providing a protrusion on the electrode body that mates with the lower surface of the cell cover, not only effectively fills the gap between the cell cover and the electrode body, improving the internal space utilization of the cell, but also increases the volume of the cell electrode assembly formed by the electrode, thereby increasing the energy density of the cell. Furthermore, at least a portion of the tab is located within the notch, meaning the remaining portion of the tab is exposed outside the notch. This provides operational space for connecting the tab to the terminal post, reducing the difficulty of connection and minimizing the possibility of damage to the electrode body during the connection process. Moreover, by providing a notch on the electrode body, operators can clearly identify the area of ​​the tab on the electrode body, reducing the time consumed during installation.

[0008] In one alternative embodiment, the height of the protrusion is 1mm-8mm.

[0009] Beneficial effects: By reasonably setting the height of the protrusion, the protrusion can effectively fill the gap between the cell cover and the electrode body, while avoiding assembly problems caused by interference with the cell cover due to its excessive height.

[0010] In one alternative embodiment, the tab and the protrusion are integrally formed with the electrode body.

[0011] Beneficial effects: The tabs and protrusions are integrally molded with the electrode body, which makes the connection between the tabs, protrusions and electrode body more stable, enhances the overall structural strength of the electrode, and effectively reduces the risk of loosening and breakage that may occur during the use of the battery cell due to loose connections between components.

[0012] In one alternative implementation, the size of the electrode tab increases from small to large along the direction from the tab to the electrode body.

[0013] Beneficial effects: Increasing the size of the tabs increases the connection area between the tabs and the electrode body, improving the stability and safety of the connection. Furthermore, as the tab size gradually increases, the current can be distributed more evenly and efficiently throughout the electrode body, ensuring the uniformity of current distribution during charging and discharging, reducing local polarization caused by uneven current distribution, thereby improving the charging and discharging efficiency of the cell and extending its cycle life.

[0014] Secondly, this utility model also provides a battery cell electrode assembly, including: a positive electrode sheet, a negative electrode sheet, and a separator, wherein the positive electrode sheet, the separator, and the negative electrode sheet are stacked, and both the positive electrode sheet and the negative electrode sheet are the aforementioned electrode sheets, wherein the tabs of the positive electrode sheet and the tabs of the negative electrode sheet are misaligned, and the tabs of the positive electrode sheet correspond to the notches of the negative electrode sheet where no tabs are provided, and the tabs of the negative electrode sheet correspond to the notches of the positive electrode sheet where no tabs are provided.

[0015] Beneficial effects: Using the aforementioned electrode material for both the positive and negative electrodes allows the resulting cell electrode assembly to have protrusions that mate with the cell cover plate. This fills the gap between the cell cover plate and the cell terminals, resulting in a more rational and compact internal space and improved energy storage capacity. Secondly, the staggered arrangement of the positive and negative electrode tabs effectively avoids the risk of short circuits between the positive and negative electrodes, improving the electrical safety of the cell electrode assembly and ensuring the normal charging and discharging process. Similarly, the alignment of the positive electrode tab with the notch on the negative electrode, and vice versa, also helps prevent short circuits between the positive and negative electrodes.

[0016] Thirdly, this utility model also provides a battery cell, comprising:

[0017] The housing has a cavity and an opening communicating with the cavity;

[0018] A cell cover plate is disposed on the opening and seals the cavity. The cell cover plate is provided with an electrode post, one end of which is located inside the cavity.

[0019] A plastic sheet abuts against the lower surface of the cell cover and has a through hole suitable for the electrode post to pass through; a plurality of the above-mentioned cell electrode groups are disposed in the cavity and arranged side by side along their stacking direction; the electrode tab abuts against and is welded to the lower surface of the electrode post; the protrusion abuts against the plastic sheet.

[0020] Beneficial effects: By providing an opening on the housing that communicates with its cavity, operators can easily assemble the cell electrode assembly and other related structures into the housing, improving assembly convenience. Furthermore, using a cell cover plate to seal the opening ensures the cell's airtightness, reducing the possibility of external moisture, dust, and other impurities entering the cell, ensuring the cleanliness and stability of the internal environment, and thus extending the cell's lifespan. Secondly, the direct welding of the electrode post and electrode tab in this invention, compared to connecting the electrode tab and electrode post with a connecting piece, reduces the internal space occupied by the connecting piece in the height direction of the housing, improving the utilization rate of the internal space, and allowing the cell to store more energy in the same volume. Moreover, the plastic plate placed between the cell electrode assembly and the cell cover plate prevents short circuits between the cell electrode assembly and the cell cover plate; it also limits the movement of the cell electrode assembly, preventing it from moving up and down along the opening direction of the housing during cell assembly. Furthermore, by setting the aforementioned cell electrode assembly inside the cell, the protrusions on the cell electrode assembly can fill the original gap between the plastic plate and the top of the cell electrode assembly. In this way, not only is the internal space utilization of the cell improved, but the energy density of the cell is also increased.

[0021] In one alternative embodiment, the lower surface of the plastic sheet is recessed toward the cell cover to form a first groove, and at least a portion of the protrusion is inserted into the first groove.

[0022] Beneficial effects: By providing a first groove on the plastic plate, the plastic plate and the protrusion are quickly positioned, reducing the time consumed in installation and positioning. Furthermore, by having at least a portion of the protrusion inserted into the first groove, a larger operating space is created between the plastic plate and the notch, reducing the difficulty of connecting the tab and the terminal and ensuring the stability of their connection. In addition, inserting at least a portion of the protrusion into the first groove also allows for a more compact internal layout of the battery cell.

[0023] In one optional embodiment, the lower surface of the cell cover is recessed to form a second groove, and the upper surface of the plastic plate is provided with a first boss that matches the second groove, the first boss being disposed opposite to the first groove.

[0024] Beneficial effects: By setting the first protrusion on the plastic sheet, the strength of the plastic sheet can be improved and the amount of deformation can be reduced. Furthermore, by setting a second groove on the lower surface of the cell cover that matches the first protrusion, the cell cover can be correctly assembled with the plastic sheet in a short time, improving installation efficiency.

[0025] In one optional embodiment, the lower surface of the plastic sheet is provided with a limiting protrusion, which abuts against the upper surface of the notch.

[0026] Beneficial effects: The limiting protrusion abuts against the upper surface of the notch, effectively preventing the cell electrode assembly from shifting vertically relative to the plastic plate due to external forces such as vibration and shaking during the use of the cell. This ensures that each component always maintains a relatively fixed position, thereby guaranteeing the stability of the overall cell structure during operation.

[0027] In one optional embodiment, the upper surface of the cell cover plate is provided with a second boss that matches the second groove, and the height of the second boss is 0-3mm.

[0028] Beneficial effects: By setting a second protrusion on the cell cover, the strength of the cell cover can be improved and the deformation of the cell cover can be reduced. Furthermore, setting the height of the second protrusion between 0-3mm ensures that the cell cover has sufficient structural strength while preventing interference with other components due to the second protrusion being too high. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of an electrode sheet according to an embodiment of the present utility model;

[0031] Figure 2 This is a schematic diagram of another electrode structure according to an embodiment of the present utility model;

[0032] Figure 3 This is a schematic diagram of the structure of a battery cell according to an embodiment of the present utility model;

[0033] Figure 4 This is a schematic diagram of the structure of a battery cell from another perspective, according to an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Electrode body; 101. Notch; 102. Protrusion; 2. Electrode tab; 3. Cell electrode assembly; 4. Cell cover plate; 401. Electrode post; 402. Second groove; 403. Explosion-proof valve; 5. Plastic plate; 501. First groove; 502. Limiting protrusion; 503. Vent hole. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0037] To address the issue of low internal space utilization in battery cells, this invention provides an electrode sheet, a battery cell electrode assembly, and a battery cell.

[0038] The following is combined with Figures 1 to 4 The following describes embodiments of the present invention.

[0039] According to embodiments of the present invention, on the one hand, such as Figures 1 to 3 As shown, an electrode is provided, including: an electrode body 1 and an electrode tab 2.

[0040] Specifically, a pair of notches 101 are provided on one side of the electrode body 1, and a protrusion 102 is formed between the pair of notches 101. The protrusion 102 is adapted to cooperate with the lower surface of the cell cover plate 4. At least a portion of the tab 2 is located in one of the notches 101 and is connected to the electrode body 1.

[0041] This embodiment, by providing a protrusion 102 on the electrode body 1 that mates with the lower surface of the cell cover plate 4, can not only effectively fill the gap between the cell cover plate 4 and the electrode body 1, improving the space utilization rate inside the cell, but also increase the volume of the cell electrode assembly 3 composed of the electrode, thereby increasing the energy density of the cell composed of the cell electrode assembly 3. Furthermore, at least a portion of the tab 2 is located within the notch 101, meaning the remaining portion of the tab 2 is exposed outside the notch 101. This provides operational space for connecting the tab 2 to the terminal post 401, reducing the difficulty of connection and minimizing the possibility of damage to the electrode body 1 during the connection process. Further, by providing the notch 101 on the electrode body 1, the operator can clearly identify the area of ​​the tab 2 on the electrode body 2, reducing the time consumed during the installation process.

[0042] According to one embodiment of the present invention, such as Figures 1 to 3As shown, the height of the protrusion 102 is 1mm-8mm. By reasonably setting the height of the protrusion 102, the protrusion 102 can effectively fill the gap between the cell cover plate 4 and the electrode body 1, while avoiding assembly problems caused by interference with the cell cover plate 4 due to its excessive height.

[0043] According to one embodiment of this utility model, the tab 2 and the protrusion 102 are integrally formed with the electrode body 1. The integral forming process of the tab 2, the protrusion 102, and the electrode body 1 ensures a more stable connection, enhances the overall structural strength of the electrode, and effectively reduces the risk of loosening or breakage that may occur during the use of the battery cell due to loose connections between components. Specifically, the tab 2 and the protrusion 102 can be directly formed on the electrode body 1 using a die-cutting process.

[0044] According to one embodiment of the present invention, such as Figure 1 and Figure 2 As shown, the size of tab 2 gradually increases from small to large along the direction from tab 2 to electrode body 1. This increasing size increases the connection area between tab 2 and electrode body 1, improving the stability and safety of the connection point. Furthermore, as the size of tab 2 gradually increases, the current can be more evenly and efficiently distributed throughout electrode body 1, ensuring uniform current distribution during charging and discharging, reducing local polarization caused by uneven current distribution, thereby improving the charging and discharging efficiency of the battery cell and extending its cycle life.

[0045] According to an embodiment of the present invention, on the other hand, as... Figure 3 As shown, a battery cell electrode assembly 3 is also provided, including: a positive electrode sheet, a negative electrode sheet and a separator. The positive electrode sheet, the separator and the negative electrode sheet are stacked. Both the positive electrode sheet and the negative electrode sheet are the aforementioned electrode sheets. The tabs 2 of the positive electrode sheet and the tabs 2 of the negative electrode sheet are misaligned. The tabs 2 of the positive electrode sheet correspond to the notch 101 of the negative electrode sheet where no tab 2 is provided. The tabs 2 of the negative electrode sheet correspond to the notch 101 of the positive electrode sheet where no tab 2 is provided.

[0046] Both the positive and negative electrodes use the aforementioned electrode material, enabling the cell electrode assembly 3 formed by them to also have a protrusion 102 that cooperates with the cell cover plate 4. This fills the gap between the cell cover plate 4 and the cell electrode post 401, making the internal space of the cell more reasonable and compact, and improving the energy storage capacity of the cell. Secondly, the staggered arrangement of the tabs 2 of the positive electrode and the tabs 2 of the negative electrode effectively avoids the risk of short circuit between the positive and negative electrodes, improves the electrical safety of the cell electrode assembly 3, and ensures the normal operation of the cell charging and discharging process. Similarly, the tabs 2 of the positive electrode correspond to the notch 101 of the negative electrode where no tab 2 is provided, and the tabs 2 of the negative electrode correspond to the notch 101 of the positive electrode where no tab 2 is provided, which also helps to prevent short circuit between the positive and negative electrodes.

[0047] According to an embodiment of the present invention, on the other hand, as... Figure 3 and Figure 4 As shown, a battery cell is also provided, including: a housing, a battery cell cover plate 4, a plastic plate 5, and multiple battery cell electrode groups 3.

[0048] Specifically, the housing has a cavity and an opening communicating with the cavity; the cell cover plate 4 is disposed on the opening and seals the cavity, and the cell cover plate 4 is provided with a pole post 401, one end of the pole post 401 being located inside the cavity; the plastic plate 5 abuts against the lower surface of the cell cover plate 4 and is provided with a through hole suitable for the pole post 401 to pass through; a plurality of the above-mentioned cell electrode groups 3 are disposed in the cavity and arranged side by side along their stacking direction, the electrode tab 2 abuts against and is welded to the lower surface of the pole post 401; the protrusion 102 abuts against the plastic plate 5.

[0049] This embodiment improves assembly convenience by providing an opening on the housing that communicates with its cavity, facilitating the assembly of the cell electrode assembly 3 and other related structures into the housing. Furthermore, the cell cover plate 4 seals the opening, ensuring the cell's airtightness and reducing the possibility of external moisture, dust, and other impurities entering the cell, thus guaranteeing the cleanliness and stability of the internal environment and extending the cell's lifespan. Secondly, in this embodiment, the electrode post 401 is directly welded to the electrode tab 2. Compared to connecting the electrode tab 2 and the electrode post 401 via a connecting piece, this reduces the internal space occupied by the connecting piece in the housing height direction, improving the utilization rate of the internal space and allowing the cell to store more energy in the same volume. Furthermore, a plastic plate 5 is placed between the cell electrode assembly 3 and the cell cover plate 4. This prevents short circuits between the cell electrode assembly 3 and the cell cover plate 4 and also limits the movement of the cell electrode assembly 3 along the opening direction of the housing during the assembly process. Furthermore, by providing the aforementioned cell electrode group 3 inside the cell in this embodiment, the protrusions 102 on the cell electrode group 3 can fill the original gap between the plastic plate 5 and the top of the cell electrode group 3. In this way, not only is the internal space utilization of the cell improved, but the energy density of the cell is also increased.

[0050] According to one embodiment of the present invention, such as Figure 3 As shown, the lower surface of the plastic plate 5 is recessed towards the cell cover plate 4 to form a first groove 501, and at least a portion of the protrusion 102 is inserted into the first groove 501. By providing the first groove 501 on the plastic plate 5, it is easy to quickly position the plastic plate 5 and the protrusion 102, shortening the time consumed in installation and positioning. Furthermore, by having at least a portion of the protrusion 102 inserted into the first groove 501, a larger operating space can be formed between the plastic plate 5 and the notch 101, reducing the difficulty of connecting the tab 2 and the terminal 401 and ensuring the stability of their connection. In addition, inserting at least a portion of the protrusion 102 into the first groove 501 also allows for a more compact internal layout of the cell.

[0051] According to one embodiment of the present invention, such as Figure 3 As shown, the lower surface of the cell cover plate 4 is recessed to form a second groove 402, and the upper surface of the plastic plate 5 is provided with a first boss that matches the second groove 402. The first boss is positioned opposite to the first groove 501. By providing the first boss on the plastic plate 5, the strength of the plastic plate 5 can be improved and the deformation of the plastic plate 5 can be reduced. Furthermore, by providing the second groove 402 that matches the first boss on the lower surface of the cell cover plate 4, the cell cover plate 4 and the plastic plate 5 can be correctly assembled in a short time, improving installation efficiency.

[0052] According to one embodiment of the present invention, such as Figure 3As shown, the lower surface of the plastic plate 5 is provided with a limiting protrusion 502, which abuts against the upper surface of the notch 101. The abutment between the limiting protrusion 502 and the upper surface of the notch 101 effectively prevents the cell electrode assembly 3 from shifting vertically relative to the plastic plate 5 due to external forces such as vibration and shaking during the use of the cell, ensuring that each component always maintains a relatively fixed positional relationship, thereby ensuring the stability of the overall structure of the cell during operation.

[0053] According to one embodiment of the present invention, such as Figure 3 As shown, the upper surface of the cell cover plate 4 is provided with a second protrusion that matches the second groove 402, and the height of the second protrusion is 0-3mm. By providing a second protrusion on the cell cover plate 4, the strength of the cell cover plate 4 can be improved and the deformation of the cell cover plate 4 can be reduced. Furthermore, setting the height of the second protrusion between 0-3mm ensures that the cell cover plate 4 has sufficient structural strength while preventing interference with other components due to the second protrusion being too high.

[0054] According to one embodiment of this utility model, an explosion-proof valve 403 is provided on the cell cover plate 4, and an exhaust hole 503 corresponding to the explosion-proof valve 403 is provided on the plastic plate 5. By providing the explosion-proof valve 403, the pressure of the cell can be released and the air can be vented in time when the cell undergoes thermal expansion, thus preventing heat spread. Furthermore, the exhaust hole 503 on the plastic plate 5 can ensure smooth airflow, ensuring that the gas can be discharged from the cell in a timely and smooth manner, maintaining the stability of the internal air pressure of the cell.

[0055] In one example, the explosion-proof valve 403 is disposed on the bottom wall of the second groove 402, and the vent 503 is disposed on the surface of the first boss facing the second groove 402.

[0056] Although 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 all fall within the scope defined by the appended claims.

Claims

1. A pole piece, characterized in that, include: The electrode body (1) has a pair of notches (101) on one side, and a protrusion (102) is formed between the pair of notches (101). The protrusion (102) is adapted to cooperate with the lower surface of the cell cover plate (4). The tab (2) is located at least partially within one of the notches (101) and is connected to the electrode body (1).

2. The pole piece of claim 1, wherein The height of the protrusion (102) is 1mm-8mm.

3. The pole piece according to claim 1 or 2, characterized in that The tab (2) and the protrusion (102) are integrally formed with the electrode body (1).

4. The pole piece according to claim 1 or 2, characterized in that Along the direction from the tab (2) to the electrode body (1), the size of the tab (2) increases from small to large.

5. An electrode group of a battery cell, characterized by comprising: include: A positive electrode, a negative electrode, and a separator are stacked together. The positive electrode and the negative electrode are both electrodes as described in any one of claims 1 to 4. The tabs (2) of the positive electrode and the tabs (2) of the negative electrode are misaligned. The tabs (2) of the positive electrode correspond to the notches (101) of the negative electrode where the tabs (2) are not provided. The tabs (2) of the negative electrode correspond to the notches (101) of the positive electrode where the tabs (2) are not provided.

6. An electric cell characterized by include: The housing has a cavity and an opening communicating with the cavity; A cell cover plate (4) is disposed on the opening and seals the cavity. A terminal post (401) is provided on the cell cover plate (4), and one end of the terminal post (401) is located in the cavity. The plastic sheet (5) abuts against the lower surface of the battery cell cover (4) and has a through hole suitable for the electrode post (401) to pass through; The battery cell electrode assembly (3) according to multiple claims 5 is disposed in the cavity and arranged side by side along its stacking direction, the electrode tab (2) abuts against and is welded to the lower surface of the electrode post (401); the protrusion (102) abuts against the plastic plate (5).

7. The electric cell of claim 6, wherein, The lower surface of the plastic sheet (5) is recessed toward the battery cell cover plate (4) to form a first groove (501), and at least a portion of the protrusion (102) is inserted into the first groove (501).

8. The battery cell according to claim 7, characterized in that, The lower surface of the cell cover plate (4) is recessed to form a second groove (402), and the upper surface of the plastic plate (5) is provided with a first boss that matches the second groove (402). The first boss is arranged opposite to the first groove (501).

9. The battery cell according to any one of claims 6 to 8, characterized in that, The lower surface of the plastic sheet (5) is provided with a limiting protrusion (502), which abuts against the upper surface of the notch (101).

10. The battery cell according to claim 8, characterized in that, The upper surface of the cell cover plate (4) is provided with a second protrusion that matches the second groove (402), and the height of the second protrusion is 0-3mm.

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