Battery cell cover plate and battery cell

Abstract

The utility model relates to lithium battery technical field provides a kind of battery cell cover plate and battery cell, including cover plate body, pole bottom plate and plastic part;Plastic part is located on cover plate body, and installation groove is formed in plastic part, and through hole is opened in installation groove, and pole bottom plate is located in installation groove, and is contacted with cover plate body by through hole;Wherein, the edge of at least one side of plastic part is opened with vent, and vent is communicated with installation groove, to be used for discharging accumulated electrolyte.The utility model, by the establishment of vent on plastic part, makes that accumulated electrolyte can be discharged in time, avoids that electrolyte is accumulated for a long time.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a cell cover plate and a cell. Background Technology

[0002] Lithium-ion batteries are widely used in various industries due to their advantages such as large capacity, high operating voltage, strong charge retention, and long cycle life. The battery cell is the smallest unit of a lithium battery pack, and it generally consists of electrode components, electrolyte, bare cell insulating sheets, a cover plate (usually integrating terminals, filling holes, explosion-proof valves, etc.), and a casing. During connection, the cover plate is fixedly connected to the casing, creating a sealed space for the electrode components.

[0003] The cover plate typically includes the terminal post, a light aluminum sheet, an upper plastic layer, a lower plastic layer, and a sealing ring. In related technologies, in the battery pack of blade cells, the cell is generally placed sideways with the cover plate upright. Electrolyte often accumulates in the gap between the terminal post base and the lower plastic rib. Over time, the electrolyte reacts with lithium ions to produce lithium dendrites. As time goes on, the lithium dendrites gradually grow outward along the gap between the terminal post base and the lower plastic rib, eventually causing a short circuit between the terminal post base and the light aluminum sheet or the casing, resulting in a safety malfunction. Utility Model Content

[0004] This utility model provides a cell cover plate and a cell to solve the defects of the prior art, which are difficult to drain the electrode liquid and have high safety risks over a long period of time.

[0005] The first aspect of this utility model provides a battery cell cover plate, comprising: a cover plate body, a terminal base plate, and a plastic component; the plastic component is disposed on the cover plate body, a mounting groove is formed in the plastic component, a through hole is opened in the mounting groove, the terminal base plate is disposed in the mounting groove, and a portion of the terminal base plate is located in the through hole; wherein, a vent is opened on at least one edge of the plastic component, the vent communicating with the mounting groove for draining accumulated electrolyte.

[0006] According to the battery cell cover provided by this utility model, a first spacer rib assembly is provided between the two sides of the electrode base plate along the length direction and the edge of the plastic part on the same side. The first spacer rib assembly is used for the discharge of electrolyte in the mounting groove and also for limiting the electrode base plate.

[0007] According to the battery cell cover provided by this utility model, the first spacer rib assembly includes a plurality of side-by-side limiting ribs, and the plurality of limiting ribs are evenly spaced along the length direction of the edge of the plastic part.

[0008] According to the battery cell cover plate provided by this utility model, each of the limiting ribs is provided with a guide slope, and the guide slope is provided between the top surface of the limiting rib and the side of the limiting rib near the mounting groove.

[0009] According to the battery cell cover plate provided by this utility model, the width of each of the limiting ribs in the length direction is 0.7-1.2mm.

[0010] According to the battery cell cover plate provided by this utility model, the distance between adjacent limiting ribs in the length direction is 1-1.5mm.

[0011] According to the battery cell cover plate provided by this utility model, a second spacer rib assembly is provided at the bottom of the mounting groove along the length direction, and the second spacer rib assembly is arranged adjacent to the first spacer rib assembly.

[0012] According to the battery cell cover provided by this utility model, the minimum distance between the two sides of the electrode base plate along the length direction and the edge of the plastic part on the same side is greater than or equal to 3.5mm-5mm.

[0013] According to the battery cell cover provided by this utility model, one of the two side walls of the plastic part is lower in the thickness direction than the other, and the vent is located on the side wall of the lower side wall.

[0014] The second aspect of this utility model provides a battery cell, including the battery cell cover plate described in any of the above claims.

[0015] The present invention provides a battery cell cover and a battery cell, which allows the accumulated electrolyte to be discharged in a timely manner by opening a vent on the plastic part, thus avoiding the long-term accumulation of electrolyte. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a partial structural schematic diagram of the battery cell provided by this utility model.

[0018] Figure 2 This is one of the internal structural schematic diagrams of the battery cell cover plate provided by this utility model.

[0019] Figure 3 This is the second schematic diagram of the internal structure of the battery cell cover provided by this utility model.

[0020] Figure label:

[0021] 1. Cell cover plate; 2. Cell; 11. Cover plate body; 12. Plastic part; 121. Drain port; 122. Mounting groove; 123. Through hole; 124. First side wall; 125. Second side wall; 13. First spacer rib assembly; 131. Limiting rib; 1311. Guide slope; 14. Second spacer rib assembly; 15. Terminal base plate. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions 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 scope of protection of this utility model.

[0023] In the description of the embodiments of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of clarifying the embodiments of this utility model and simplifying the description, and 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. Therefore, they should not be construed as limitations on the embodiments of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model according to the specific circumstances.

[0025] In this embodiment of the utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0027] The following is combined Figures 1-3 This invention describes a battery cell cover plate, comprising a cover plate body 11, a terminal base plate 15, and a plastic component 12. The plastic component 12 is disposed on the cover plate body 11, and an installation groove 122 is formed within the plastic component 12. A through hole 123 is provided within the installation groove 122. The terminal base plate 15 is disposed within the installation groove 122, and a portion of the terminal base plate 15 is located within the through hole 123. At least one edge of the plastic component 12 has a drain port 121, which communicates with the installation groove 122 to drain accumulated electrolyte. Typically, electrolyte seeps into the gap between the terminal base plate 15 and the plastic component 12. Over time, the electrolyte accumulates around the terminal base plate 15. Over time, the electrolyte reacts with lithium ions to produce lithium dendrites. As time progresses, the lithium dendrites gradually grow outward along the gap between the terminal base plate 15 and the plastic component, leading to faults such as short circuits. In this embodiment, a vent 121 is opened on one side of the plastic part 12 and the vent 121 is connected to the mounting groove 122, so that the electrode liquid can be discharged in time, avoiding the situation of lithium dendrites growing outward due to long-term accumulation, improving safety performance, and reducing the risk of short circuit between the electrode base plate 15 and the cover plate or shell caused by lithium dendrite growth.

[0028] Specifically, the cover plate body 11 includes a light aluminum sheet, on which a plastic part 12 is formed. The plastic part 12 serves as an installation platform for the electrode base plate 15. The electrode base plate 15 has a columnar solid portion located within a through hole and spaced from the inner wall of the through hole 123. The plastic part 12 as a whole can act as an insulating layer, providing a certain degree of protection. In this embodiment, by opening a vent 121 on one side of the plastic part 12, the electrolyte can be allowed to flow out in a timely manner, avoiding long-term accumulation of electrolyte and reducing the risk of short circuit.

[0029] The plastic component 12 is made of rigid plastic, which provides sufficient strength, rigidity, and durability to ensure that the battery cover can withstand external pressure, vibration, impact, and other factors during actual use without deformation or damage. Specifically, engineering plastics or injection-molded rigid plastics can be used. For example, polypropylene, polycarbonate, and other materials can be used.

[0030] In the specific setup, the bottom surface of the vent 121 is flush with the bottom surface of the mounting groove 122, which facilitates the timely discharge of electrolyte and avoids long-term accumulation of electrolyte.

[0031] It is understandable that lithium batteries, especially blade batteries, require careful installation and placement, such as... Figure 1 As shown, the terminals of cell 2 are usually oriented downwards, and electrolyte often exists in the gap between the terminal base plate 15 and the plastic part 12. The electrolyte flows downwards, such as... Figure 3 The flow direction is shown. In related technologies, to achieve high structural strength in the plastic part 12, a grid-like reinforcing rib structure is often set in the area outside the mounting groove 122. This results in a "barrier" structure around the mounting perimeter, causing the electrolyte to accumulate in the space between the electrode base plate 15 and the mounting groove 122. Prolonged accumulation of the electrolyte will react with lithium ions to produce lithium dendrites, which will gradually grow outwards along the gap between the electrode base plate 15 and the plastic part 12. In this embodiment, by opening a drain port 121 on the side, the electrolyte accumulated in the mounting groove 122 can be drained in a timely manner, thus avoiding the problem of lithium dendrite growth due to prolonged accumulation.

[0032] In specific settings, such as Figure 3 As shown, the vent 121 is constructed with a notch structure, which is located at the bottom of the mounting groove 122 along the electrolyte flow direction. This allows the accumulated electrolyte to be discharged in time, preventing lithium dendrites from growing along the gap between the electrode base plate 15 and the plastic part 12.

[0033] In some embodiments, the cell cover plate 1 structure includes first spacer rib assemblies 13 between the two sides of the electrode base plate 15 in the width direction Y and the edge of the plastic part 12 on the same side. The first spacer rib assemblies 13 are used for electrolyte drainage from the mounting groove 122 and also for limiting the position of the electrode base plate 15. In conventional cell cover plates 1, the mounting perimeter is a raised rib structure, which creates a storage space between the mounting groove 122 and the electrode base plate 15, making electrolyte drainage difficult. In this embodiment, the first spacer rib assemblies 13 allow the storage space between the mounting groove 122 and the electrode base plate 15 to communicate with the outside, thereby facilitating electrolyte drainage.

[0034] Specifically, the first spacer rib assembly 13 forms the overall outline of the mounting groove 122. This method makes the mounting groove 122 have an intermittent gap structure around it. The intermittent gap structure enables the internal storage space of the mounting groove 122 to be connected with the external space, thus avoiding the long-term accumulation of electrolyte.

[0035] It should be understood that in blade batteries, the cell cover 1 of a single cell 2 is typically a rectangular parallelepiped structure with a length direction X and a width direction Y, and the length distance is much greater than the width distance, thus forming a long strip structure. In this embodiment, the length direction X is as follows: Figure 3 The direction of electrolyte flow.

[0036] Understandably, the space between the traditional electrode base plate 15 and the mounting groove 122 is a relatively enclosed space, making it difficult for the electrolyte to drain. This causes lithium dendrites to easily grow along the gap between the electrode base plate 15 and the plastic part 12, resulting in short circuits and other problems, thus reducing the service life of the battery cell 2. In this embodiment, the first spacer rib assembly 13, in conjunction with the structure of the drain port 121 in the aforementioned embodiment, allows the electrolyte to drain promptly from the accumulation space between the mounting groove 122 and the electrode base plate 15, effectively preventing the growth of lithium dendrites along the gap between the electrode base plate 15 and the plastic part 12.

[0037] In conjunction with the above embodiments, the specific structure of the first spacer rib assembly 13 includes multiple parallelly arranged limiting ribs 131, which are evenly spaced along the length direction X of the edge of the plastic part 12. The first spacer rib assembly 13 needs to enable the electrolyte in the mounting groove 122 to flow out in a timely manner to avoid long-term accumulation. In this embodiment, there is a certain gap between the limiting ribs 131, which allows the electrolyte to drain through the gaps, and the limiting ribs 131 also ensure the overall structural strength of the plastic part 12.

[0038] Specifically, such as Figure 2 , Figure 3As shown, the mounting groove 122 has multiple limiting ribs 131 arranged side by side on two opposite sides in the direction of high difficulty in wiping sweat, and the multiple limiting ribs 131 cover a part of the length of the edge. That is, the first spacer rib assembly 13 forms part of the length edge of the mounting groove 122, and the other part of the length edge of the mounting groove 122 is a continuous "barrier-like" rib structure. This method takes into account both the structural strength of the plastic part 12 and the connectivity of the mounting groove 122.

[0039] It is understandable that the plastic part 12 needs to bear a part of the force, thus requiring the plastic part 12 to have a certain structural strength. In this embodiment, the spaced limiting ribs 131 can define the overall outline shape of the mounting groove 122 on the one hand, and on the other hand, the limiting ribs 131 can strengthen the overall structural strength of the plastic part 12, making the overall structural strength higher.

[0040] In conjunction with the above embodiments, each limiting rib 131 is provided with a guide slope 1311, which is located between the top surface of the limiting rib 131 and the side of the limiting rib 131 near the mounting groove 122. Normally, the limiting rib 131 is integrally formed with the plastic part 12. In this embodiment, the guide slope 1311 facilitates the installation of the pole base plate 15 and avoids interference problems during installation.

[0041] Specifically, guide slopes 1311 are provided on both sides of the lower limit ribs 131, which allows the pole base plate 15 to be guided by the guide slopes 1311 during installation, thus facilitating the installation of the pole base plate 15.

[0042] In conjunction with the above embodiments, a second spacer rib assembly 14 is provided at the bottom of the mounting tank 122 along the length X direction (electrolyte flow direction), and the second spacer rib assembly 14 is arranged adjacent to the first spacer rib assembly 13. If the electrolyte accumulates in the mounting tank 122 for a long time, there is a risk that lithium dendrites will grow along the gap between the electrode base plate 15 and the plastic part 12. In this embodiment, by providing a spacer rib structure at the bottom of the mounting tank 122 along the electrolyte flow direction, this method can facilitate the timely discharge of electrolyte and prevent electrolyte accumulation in the mounting tank 122.

[0043] Specifically, the second spacer rib assembly 14 has the same structure as the first spacer rib assembly, both including multiple parallel limiting ribs 131. The difference is that the second spacer rib assembly 14 is arranged along the width direction Y of the plastic part 12, which makes the bottom of the mounting groove 122 open in the length direction, so that the electrolyte will not accumulate in the mounting groove 122.

[0044] In the first spacer assembly 13 and the second spacer assembly 14, the distance between adjacent limiting ribs 131 can be set to be the same or different. In this embodiment, the spacing W between adjacent limiting ribs 131 is not specifically limited, and it can be adjusted according to the position and design requirements.

[0045] It is understandable that the second spacer rib assembly 14 serves as one side of the mounting groove 122. On the one hand, it can cooperate with the adjacent first spacer rib assembly to form the outline shape of the edge of the mounting groove 122. On the other hand, it can discharge the electrolyte in time through the gap between the adjacent limiting ribs 131 in the second spacer rib assembly 14, so as to avoid the electrolyte from accumulating in the mounting groove 122.

[0046] In conjunction with the above embodiments, the distance W between adjacent limiting ribs 131 in the length direction X is 1-1.5mm. Most of the electrolyte is discharged through the gap between adjacent limiting ribs 131. However, an excessively large gap will affect the overall structural strength, which is not conducive to improving the life of the battery cell 2. On the other hand, an excessively small gap will increase the processing difficulty and affect the timely discharge of electrolyte. In this embodiment, the distance W between adjacent limiting ribs 131 is limited to 1-1.5mm, which can balance the overall strength of the plastic part 12 and the smoothness of electrolyte flow, thereby improving the overall life of the battery cell 2.

[0047] Specifically, the gap between adjacent limiting ribs 131 is 1.2mm. With this gap distance, the molding of the limiting ribs 131 is simple and can enhance the overall structural strength of the plastic part 12, achieving a balance between electrolyte flow and strength.

[0048] In conjunction with the above embodiments, the width of each limiting rib 131 in the length direction X is t = 0.7-1.2 mm. As part of the battery cell 2, the cover plate has a limited overall structure. In this embodiment, by limiting the width t of each limiting rib 131, the arrangement of multiple limiting ribs 131 can be realized, thereby improving the overall structural strength of the plastic part 12.

[0049] Specifically, the width t of the limiting rib 131 affects the number of limiting ribs 131 provided in the confined space and the strength of a single limiting rib 131. In this embodiment, by limiting the width of the limiting rib 131 to between 0.7-1.2 mm, both the strength and the number of limiting ribs 131 can be considered, thereby balancing strength and smooth electrolyte flow within the confined space. For example, a single limiting diameter width of 0.7 mm allows for the arrangement of more limiting ribs 131 in the same location. Alternatively, a single limiting diameter width of 1.2 mm reduces the number of limiting ribs 131 arranged in the same location, but increases the strength of a single limiting rib 131.

[0050] In conjunction with the above embodiments, the distance A between the two sides of the electrode base plate 15 along its length X and the edge of the plastic part 12 on the same side is 3.5mm-5mm. Electrolyte accumulates between the mounting groove 122 and the side wall of the electrode base plate 15. In this embodiment, by increasing the distance between the electrode base plate 15 along its length X and the plastic part 12, the width of the electrode base plate 15 is narrowed. This minimizes electrolyte accumulation and allows for timely discharge of the electrolyte.

[0051] Specifically, the distance between the two side walls of the electrode base plate 15 in the length direction X and the plastic part 12 is usually small, which results in the electrolyte not having a timely outflow channel. If the distance is too large, it will lead to a decrease in the overall structural strength and an increase in the defect rate during the production process. In this embodiment, by limiting the distance on both sides, it is possible to facilitate the timely discharge of electrolyte and ensure the overall structural strength.

[0052] In some embodiments, one of the two opposing sidewalls of the plastic part 12 is lower in height along the thickness direction Z than the other, and the drain port 121 is located on the sidewall of the sidewall with the lower height. Specifically, the plastic part 12 has a first sidewall 124 and a second sidewall 125 opposing each other, the first sidewall 124 being higher than the second sidewall 125, and the drain port 121 being located on the second sidewall 125. By placing the drain port 121 on the second sidewall 125, the electrolyte can be discharged in a timely manner without affecting the overall structural strength of the cover plate.

[0053] Specifically, the pole base plate 15 is disposed on the main body in the width direction Y between the first side wall 124 and the second side wall 125, and a grid-shaped reinforcing rib is provided on the plastic part 12 on the side away from the pole base plate 15, which improves the overall strength of the plastic part 12.

[0054] like Figure 1 As shown, a second aspect of this utility model provides a battery cell 2, including the battery cell cover plate 1 provided in any of the above embodiments. The battery cell 2 includes a housing, an electrode assembly, an electrolyte, a bare battery cell 2 insulating sheet, and the battery cell cover plate 1, wherein the battery cell cover plate 1 is the battery cell cover plate 1 provided in the above embodiments.

[0055] Specifically, the battery cell 2 provided in this example has the battery cell cover plate 1 structure of any of the aforementioned embodiments. Therefore, the battery cell 2 in this embodiment has the characteristic effects of each of the aforementioned battery cell cover plate 1 structures. To avoid redundancy in the effect description, it will not be repeated here.

[0056] Through the above description of the embodiments, those skilled in the art can clearly understand that by opening the vent 121 on the plastic part 12, the accumulated electrolyte can be discharged in a timely manner, avoiding prolonged accumulation of electrolyte. Furthermore, by spaced out multiple limiting posts, the overall structural strength of the plastic part 12 can be taken into account, and the timely discharge of electrolyte can be achieved, thereby improving the service life of the battery cell 2.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A battery cell cover plate, characterized in that, include: The cover plate body, the pole base plate, and the plastic part; the plastic part is disposed on the cover plate body, the plastic part has a mounting groove formed in the plastic part, the mounting groove has a through hole, the pole base plate is disposed in the mounting groove, and a part of the pole base plate is located in the through hole; The plastic part has a vent on at least one side edge, and the vent is connected to the mounting groove to drain the accumulated electrolyte.

2. The cell cover plate according to claim 1, characterized in that, The electrode base plate is provided with first spacer ribs on both sides of its width direction and between the plastic part on the same side. The first spacer ribs are used to drain the electrolyte in the mounting groove and to limit the position of the electrode base plate.

3. The cell cover plate according to claim 2, characterized in that, The first spacer rib assembly includes a plurality of side-by-side limiting ribs, which are evenly spaced along the length of the edge of the plastic part.

4. The cell cover plate according to claim 3, characterized in that, Each of the limiting ribs is provided with a guide slope, which is located between the top surface of the limiting rib and the side of the limiting rib near the mounting groove.

5. The cell cover plate according to claim 3, characterized in that, Each of the aforementioned limiting ribs has a width of 0.7-1.2 mm in the length direction.

6. The cell cover plate according to claim 3, characterized in that, The spacing between adjacent limiting ribs in the length direction is 1-1.5mm.

7. The cell cover plate according to claim 2 or 3, characterized in that, A second spacer rib assembly is provided at the bottom along the length of the mounting groove, and the second spacer rib assembly is arranged adjacent to the first spacer rib assembly.

8. The cell cover plate according to claim 1, characterized in that, The distance between the two sides of the pole base plate along its length and the edge of the plastic part on the same side is 3.5mm-5mm.

9. The cell cover plate according to any one of claims 1-3, characterized in that, One of the two opposing sidewalls of the plastic part is lower in the thickness direction than the other, and the vent is located on the sidewall of the sidewall with the lower height.

10. A battery cell, characterized in that, Includes the cell cover plate as described in any one of claims 1-9.

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