Battery cell packaging structure, packaging device and battery cell
Patent Information
- Application Number
- CN202522329817.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-03
- Publication Date
- 2026-09-29
- Estimated Expiration
- 2035-11-03
AI Technical Summary
[0004]有鉴于此，本实用新型提供了一种电芯封装结构、封装设备及电芯，以解决电芯注液污染精封区域的PP层而造成封装不良的问题
[0006]有益效果：通过在冲坑区与气袋区设置预封边，且预封边包括沿X方向间隔设置的第一预封段和第二预封段，使得预封边上具有连通冲坑区与气袋区的通道，通道可以允许后续电芯注液过程中的电解液通过，以及电芯化成过程中所产生的气体由冲坑区导入气袋区的气袋中，则保证电芯注液及排气的同时，可以减少电解液对精封区域PP层的污染，从而保证后续的精封效果，避免出现封装不良，并且通过设置第一预封段的长度大于第二预封段的长度，使得通道偏离预封边沿X方向的中心设置，则在电芯注液及化成等后续工序中，可以保持电芯的具有第二预封段的一侧抬起一定的角度，从而保证电解液不会污染通道，进一步保证后续精封的封装效果，提高电芯的可靠性。
Smart Images
Figure CN224817219U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of battery technology, specifically to cell packaging structure, packaging equipment, and cell. Background Technology
[0002] A battery cell consists of electrode groups and an encapsulation film disposed on the outside of the electrode groups. The encapsulation film typically includes an outer nylon layer, an intermediate aluminum layer, and an inner heat-sealing layer. The heat-sealing layer is made of PP (Polypropylene). After being heated and melted, the PP layer acts as an adhesive, bonding the two encapsulation films together to form a sealed internal cavity of the battery cell to accommodate the electrode groups.
[0003] The battery cell packaging process typically includes top-side sealing, electrolyte filling, pre-sealing, formation, degassing, and final sealing. During top-side sealing, the PP layer is not contaminated by the electrolyte, resulting in a relatively good seal. However, final sealing is performed after electrolyte filling, and some electrolyte adheres to the PP layer in the final-sealed area. Consequently, during subsequent final sealing, this contaminated PP layer often results in poor sealing and can easily lead to encapsulation defects. Utility Model Content
[0004] In view of this, the present invention provides a battery cell packaging structure, packaging equipment and battery cell to solve the problem of poor packaging caused by electrolyte injection contaminating the PP layer in the precision sealing area.
[0005] In a first aspect, this utility model provides a battery cell packaging structure, comprising: an electrode assembly, including an electrode assembly body and electrode tabs; and a packaging film, including a perforated area and an air bag area spaced apart along the Y direction. The perforated area has perforations suitable for placing the electrode assembly body in the perforations. A first sealing edge is provided on the side of the perforated area away from the air bag area along the Y direction. A second sealing edge and a third sealing edge are provided on both sides of the packaging film along the X direction. A pre-sealing edge is provided between the perforated area and the air bag area. The pre-sealing edge includes a first pre-sealing segment and a second pre-sealing segment spaced apart along the X direction. A channel is formed between the first pre-sealing segment and the second pre-sealing segment. The length of the first pre-sealing segment along the X direction is greater than the length of the second pre-sealing segment along the X direction.
[0006] Beneficial effects: By setting a pre-sealing edge in the punching area and the air bag area, and the pre-sealing edge including a first pre-sealing section and a second pre-sealing section spaced apart along the X direction, a channel is formed on the pre-sealing edge connecting the punching area and the air bag area. The channel allows the electrolyte to pass through during the subsequent cell liquid injection process, and the gas generated during the cell formation process to be introduced from the punching area into the air bag in the air bag area. This ensures that while the cell liquid injection and venting are carried out, the contamination of the PP layer in the fine sealing area by the electrolyte can be reduced, thereby ensuring the subsequent fine sealing effect and avoiding poor sealing. Furthermore, by setting the length of the first pre-sealing section to be greater than the length of the second pre-sealing section, the channel is set off from the center of the pre-sealing edge along the X direction. In subsequent processes such as cell liquid injection and formation, the side of the cell with the second pre-sealing section can be raised at a certain angle, thereby ensuring that the electrolyte will not contaminate the channel, further ensuring the subsequent fine sealing effect and improving the reliability of the cell.
[0007] In one alternative implementation, the ratio between the length of the second pre-sealed section and the length of the first pre-sealed section along the X direction ranges from 1 / 5 to 1 / 3.
[0008] Beneficial effects: By reasonably setting the length ratio of the first pre-sealing section to the second pre-sealing section, it is possible to ensure that the second pre-sealing section is processed and formed smoothly, and to ensure that the channel deviates from the center of the X direction of the pre-sealing edge to a moderate degree, effectively preventing the electrolyte from flowing out of the channel and contaminating the channel, thereby ensuring the encapsulation effect of subsequent fine sealing.
[0009] In one optional implementation, the dimension of the channel along the X direction ranges from 10 mm to 30 mm.
[0010] Beneficial effects: It can ensure smooth electrolyte flow, improve the electrolyte injection efficiency of the cell, ensure the smooth discharge of gas during the cell formation process, maintain the sealing strength of the pre-sealed edge, prevent electrolyte backflow and contamination of the channel, and thus ensure the encapsulation effect of subsequent fine sealing.
[0011] In one alternative embodiment, the tab extends from the side of the third sealing edge on the encapsulation film, the first pre-sealed section is connected to the second sealing edge, and the second pre-sealed section is connected to the third sealing edge.
[0012] Beneficial effects: By setting a relatively short second pre-sealing section in the pre-sealing edge to connect with the third sealing edge with the tab, that is, the channel is set towards the tab in the X direction, the side where the tab is located can be raised at a certain angle during subsequent liquid injection and formation processes. This facilitates the lifting of the cell packaging structure, thereby ensuring that the electrolyte does not contaminate the channel and also preventing the tab from being damaged by pressure.
[0013] In one alternative embodiment, the cell packaging structure is adapted to be placed at an angle to the horizontal plane, with the side containing the third sealing edge higher than the side containing the second sealing edge.
[0014] Beneficial effects: The channel is set on the side where the tab is located, and the cell packaging structure is placed with the tab side raised. This can prevent the electrolyte in the pit area from flowing to the air bag area through the channel, thus avoiding electrolyte contamination of the channel and ensuring the subsequent fine sealing effect. At the same time, during the cell formation process, the gas generated can smoothly enter the air bag area from the pit area through the channel, ensuring the normal discharge of gas inside the cell.
[0015] In one optional embodiment, the angle between the cell packaging structure and the horizontal plane is 30° to 60°.
[0016] Beneficial effects: It can effectively avoid electrolyte contamination of the channels in the flushing area, ensuring the subsequent fine sealing effect, and also ensure that the electrolyte fully wets the electrode assembly, improving the overall performance of the cell.
[0017] In one alternative embodiment, the cell packaging structure further includes a fourth sealing edge, which is located on the side of the air bag area opposite to the pit area along the Y direction.
[0018] In one optional embodiment, the pre-sealing edge is adapted to be finely sealed after cell formation and venting. The thickness of the pre-sealing edge in the Z direction at the fine sealing front is a first preset thickness, and the thickness of the pre-sealing edge in the Z direction after fine sealing is a second preset thickness. The first preset thickness is 1.1 to 1.5 times the second preset thickness.
[0019] Beneficial effects: It can reduce the temperature and pressure required for pre-sealing, ensure that the pre-sealed edge has a certain sealing strength, ensure the smooth progress of liquid injection and formation processes, reduce the operational difficulty of subsequent fine sealing processes, and improve the production yield of battery cells.
[0020] Secondly, this utility model also provides a packaging device for packaging the above-mentioned battery cell packaging structure. The packaging device includes: a device body; a precision sealing head connected to the device body. The precision sealing head is used to precision seal the pre-sealed edge. The precision sealing head includes a sealing head body and a protrusion connected to the sealing head body. The protrusion corresponds to the channel.
[0021] Beneficial effects: By setting the precision sealing head, which includes the head body and the protrusion, the precision sealing head layer is "T" shaped, with the protrusion corresponding to the channel. The area on both sides of the protrusion along the X direction on the precision sealing head corresponds to the first pre-sealing section and the second pre-sealing section. This allows for the simultaneous precision sealing of the first pre-sealing section, the second pre-sealing section, and the channel, ensuring the smooth progress of the precision sealing process.
[0022] Thirdly, this utility model also provides a battery cell, which is manufactured from the aforementioned battery cell packaging structure. Since the battery cell includes the battery cell packaging structure and has the same effects as the battery cell packaging structure, it will not be described in detail here. Attached Figure Description
[0023] 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.
[0024] Figure 1 This is a schematic diagram of the encapsulation film structure after top-side sealing according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the encapsulation film structure after pre-sealing according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the encapsulation film structure after pre-sealing according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the encapsulation film structure after precision sealing, according to an embodiment of the present invention. Figure 5 This is a schematic diagram of the structure of a precision sealing head according to an embodiment of the present utility model; Figure 6 This is a schematic diagram of the structure of a battery cell according to an embodiment of the present utility model; Figure 7 This is a schematic diagram of the top-side sealing structure of a pre-improved encapsulation film structure.
[0025] Explanation of reference numerals in the attached figures: 1. Tab; 2. Encapsulation film; 201. First sealing edge; 202. Second sealing edge; 203. Third sealing edge; 204. Fourth sealing edge; 21. Punching area; 22. Air bag area; 23. Pre-sealing edge; 231. First pre-sealing section; 232. Second pre-sealing section; 233. Channel; 24. Fine sealing edge; 3. Fine sealing head; 31. Head body; 32. Protrusion. Detailed Implementation
[0026] 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.
[0027] Soft-pack battery cells use aluminum-plastic film as the outer casing material. This film is a multi-layered film composed of an outer nylon layer, adhesive, an inner aluminum foil layer, and an inner heat-sealing layer (PP), forming the outer packaging material for the soft-pack battery. The PP layer, after being heat-melted, acts as an adhesive, bonding the two aluminum-plastic film layers together to form a sealed internal cavity within the battery cell. The sealing processes typically involve top and side sealing, pre-sealing, and precision sealing. Pre-sealing is temporary, while precision sealing is removed along with the soft-pack air bag, requiring relatively lower sealing standards; it only needs to maintain a tight seal during battery cell production. However, top and side sealing and precision sealing accompany the entire lifecycle of the soft-pack battery cell, needing to withstand years or even decades of testing under various complex operating conditions, thus requiring excellent sealing performance.
[0028] The packaging process for soft-pack batteries is as follows: front-end process → top-side sealing → electrolyte injection → pre-sealing → formation → DEGAS → fine sealing → subsequent processes. During top-side sealing of soft-pack batteries, the PP layer is not contaminated by the electrolyte, resulting in good sealing performance. However, after electrolyte injection, some electrolyte contamination adheres to the PP layer in the fine-sealing area. During fine sealing, this contaminated PP layer often results in poor sealing performance, easily leading to encapsulation defects. A common practice in existing technologies is to increase the sealing temperature and pressure during fine sealing. However, this approach easily leads to over-sealing, where too much of the PP layer is melted, causing the aluminum layer to be exposed in the electrolyte, resulting in poor edge resistance, which is a serious concern in soft-pack batteries.
[0029] The following is combined Figures 1 to 7 The following describes embodiments of the present invention.
[0030] According to embodiments of the present invention, in one aspect, a cell packaging structure is provided, such as... Figures 1 to 4As shown, the battery cell packaging structure includes: an electrode assembly and a packaging film 2. The electrode assembly includes an electrode assembly body and electrode tabs 1; the packaging film 2 includes a perforated area 21 and an air pocket area 22 spaced apart along the Y direction. The perforated area 21 has perforations suitable for placing the electrode assembly body. A first sealing edge 201 is provided on the side of the perforated area 21 opposite to the air pocket area 22 along the Y direction. A second sealing edge 202 and a third sealing edge 203 are provided on both sides of the packaging film 2 along the X direction. A pre-sealing edge 23 is provided between the perforated area 21 and the air pocket area 22. The pre-sealing edge 23 includes a first pre-sealed section 231 and a second pre-sealed section 232 spaced apart along the X direction. A channel 233 is formed between the first pre-sealed section 231 and the second pre-sealed section 232. The dimension of the first pre-sealed section 231 along the X direction is larger than the dimension of the second pre-sealed section 232 along the X direction. Here, the X direction refers to... Figures 1 to 4 The direction indicated by the middle arrow ("X") is the direction of the Y direction. Figures 1 to 4 The direction of the "Y" indicated by the middle arrow.
[0031] It should be noted that the battery cell packaging structure has two perpendicular X, Y, and Z directions, such as... Figures 1 to 4 As shown, the X, Y, and Z directions form a rectangular coordinate system.
[0032] It should be noted that the area covered by the pre-sealed edge 23 is the area of the battery cell that needs to be finely sealed in the end.
[0033] By applying the cell packaging structure of this embodiment, a pre-sealing edge 23 is provided between the punching area 21 and the air bag area 22. The pre-sealing edge 23 includes a first pre-sealing section 231 and a second pre-sealing section 232 spaced apart along the X direction. This allows the pre-sealing edge 23 to have a channel 233 connecting the punching area 21 and the air bag area 22. The channel 233 allows the electrolyte to pass through during the subsequent cell electrolyte injection process, and the gas generated during the cell formation process is introduced from the punching area 21 into the air bag in the air bag area 22. This ensures that the cell electrolyte injection and venting are carried out simultaneously, while reducing the risk of electrolyte buildup. Less electrolyte contamination of the PP layer in the precision sealing area ensures the subsequent precision sealing effect and avoids poor sealing. Furthermore, by setting the length of the first pre-sealing section 231 to be greater than the length of the second pre-sealing section 232, the channel 233 is offset from the center of the pre-sealing edge 23 in the X direction. In subsequent processes such as cell electrolyte injection and formation, the side of the cell with the second pre-sealing section 232 can be raised at a certain angle, thereby ensuring that the electrolyte does not contaminate the channel 233, further ensuring the subsequent precision sealing effect and improving the reliability of the cell.
[0034] In one embodiment, the ratio of the length of the second pre-sealing segment 232 to the length of the first pre-sealing segment 231 along the X direction ranges from 1 / 5 to 1 / 3. If the ratio is less than 1 / 5, the size of the second pre-sealing segment 232 is too small, making it difficult to process and form; if the ratio is greater than 1 / 3, the size of the second pre-sealing segment 232 is relatively too large, and the channel 233 is not sufficiently offset from the center of the pre-sealing edge 23 along the X direction. In subsequent cell electrolyte injection and formation processes, electrolyte may flow out of the channel 233, contaminating the channel 233 and affecting the subsequent fine sealing effect. Therefore, by reasonably setting the length ratio of the first pre-sealing segment to the second pre-sealing segment, it is possible to ensure that the second pre-sealing segment 232 can be processed and formed smoothly, and that the channel 233 is appropriately offset from the center of the pre-sealing edge along the X direction, effectively preventing electrolyte from flowing out of the channel 233 and contaminating the channel 233, thereby ensuring the subsequent fine sealing effect.
[0035] Optionally, the ratio between the length of the second pre-sealed section 232 and the length of the first pre-sealed section 231 is any one of 1 / 5, 1 / 4, 7 / 24, 1 / 3, or a value between any two of these values.
[0036] In one embodiment, the dimension of channel 233 along the X direction ranges from 10 mm to 30 mm. If the dimension of channel 233 along the X direction is less than 10 mm, the channel 233 is too small, the electrolyte flow is not smooth, which may affect the electrolyte injection efficiency of the cell. In addition, during the cell formation process, the gas may not be able to pass smoothly through channel 233 into the gas bag area 22, resulting in the gas in the pit area 21 not being fully discharged, which seriously affects the pass rate of the cell. If the dimension of channel 233 along the X direction is greater than 30 mm, the sealing area of the pre-sealing edge 23 is reduced accordingly, which may reduce the sealing strength of the pre-sealing edge 23. In subsequent processes, poor sealing is likely to occur. Furthermore, the electrolyte injected into the pit area 21 is likely to flow back from channel 233 into the gas bag, contaminating channel 233 and causing poor sealing effect in subsequent fine sealing. Therefore, controlling the channel size in the X direction within the range of 10 mm to 30 mm can ensure smooth electrolyte flow, improve cell electrolyte injection efficiency, ensure smooth gas discharge during cell formation, maintain the sealing strength of the pre-sealed edge 23, prevent electrolyte backflow and contamination of the channel 233, and thus ensure the encapsulation effect of subsequent fine sealing.
[0037] Optionally, the dimension of channel 233 along the X direction is any value of 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, or a value between any two of these values.
[0038] In one embodiment, the tab 1 extends from the side of the third sealing edge 203 on the encapsulation film 2. The first pre-sealing section 231 is connected to the second sealing edge 202, and the second pre-sealing section 232 is connected to the third sealing edge 203. By setting the relatively short second pre-sealing section 232 of the pre-sealing edge 23 to connect with the third sealing edge 203 where the tab 1 is located, that is, the channel 233 is biased towards the tab 1 in the X direction, the side of the cell where the tab 1 is located can be raised at a certain angle during subsequent electrolyte injection, formation, and DEGAS processes. This facilitates the lifting of the cell encapsulation structure, thereby ensuring that the electrolyte does not contaminate the channel 233 and also preventing the tab 1 from being damaged by pressure.
[0039] In one embodiment, the cell packaging structure is adapted to be placed at an angle to the horizontal plane, with the vertical distance from the third sealing edge 203 to the horizontal plane being greater than the vertical distance from the second sealing edge 202 to the horizontal plane along a direction perpendicular to the horizontal plane. It should be noted that placing the cell packaging structure at an angle to the horizontal plane means that the cell packaging structure is tilted relative to the horizontal plane during the liquid injection, formation, and DEGAS processes. The direction perpendicular to the horizontal plane is the vertical direction, and the vertical distance refers to the distance along the vertical direction. The greater vertical distance from the third sealing edge 203 to the horizontal plane than the greater vertical distance from the second sealing edge 202 to the horizontal plane makes the side of the cell packaging structure where the third sealing edge 203 is located higher than the side where the second sealing edge 202 is located along the vertical direction. In other words, by raising the third sealing edge 203, the electrode on the cell packaging structure... The side with tab 1 is higher than the side without tab 1. Due to gravity, the electrolyte in the pit area 21 will mainly flow to the lower side of the cell. The channel 233 is set on the side with tab 1, and the cell packaging structure is placed with the tab side raised. This can prevent the electrolyte in the pit area 21 from flowing to the air bag area 22 through the channel 233, thus avoiding electrolyte contamination of the channel 233 and ensuring the subsequent fine sealing effect. At the same time, during the cell formation process, the gas generated can smoothly enter the air bag area 22 from the pit area 21 through the channel, ensuring the normal discharge of gas inside the cell.
[0040] In one embodiment, the angle between the cell packaging structure and the horizontal plane is 30° to 60°. If the angle is less than 30°, the tilt of the cell packaging structure is insufficient, and the electrolyte may still flow into the channel 233, contaminating the channel 233 and affecting the subsequent fine sealing effect. If the angle is greater than 60°, the cell packaging structure is over-tilted, making it difficult for the electrolyte to wet the electrode assembly, affecting the overall performance of the cell. Therefore, controlling the angle between the cell packaging structure and the horizontal plane within the range of 30° to 60° can effectively prevent electrolyte contamination of the channel 233 in the pit area 21, ensuring the subsequent fine sealing effect, and also ensure that the electrolyte fully wets the electrode assembly, improving the overall performance of the cell. In actual operation, placing the cell packaging structure at an angle of 30° to 60° can be achieved using specialized tooling fixtures.
[0041] Optionally, the angle between the cell packaging structure and the horizontal plane is any value of 30°, 35°, 40°, 45°, 50°, 55°, or 60°, or a value between any two of these values.
[0042] In one embodiment, further combination Figure 3 and Figure 4 As shown, the cell packaging structure also includes a fourth sealing edge 204, which is located on the side of the air bag area 22 facing away from the punched pit area 21 along the Y direction. By setting the fourth sealing edge 204 on the side of the air bag area 22 facing away from the punched pit area 21 along the Y direction, the first sealing edge 201, the third sealing edge 203, the second sealing edge 202, and the fourth sealing edge 204 are connected end to end in sequence, thus completing the circumferential sealing of the packaging film 2, making the packaging film 2 form a sealed inner cavity, which facilitates the subsequent formation process.
[0043] It should be noted that the encapsulation film 2 has two films that are interlocked with each other along the Z direction, and at least one film is provided with a perforation, and the body part of the electrode assembly is located in the perforation; the fourth sealing edge 204 is a sealing edge that is processed after the cell liquid injection process, and plays the role of temporarily sealing the inner cavity of the cell. After the cell completes formation, DEGAS and fine sealing, the fourth sealing edge 204 will be cut off together with the air bag area 22.
[0044] In one embodiment, the pre-sealing edge 23 is adapted to be finely sealed after the cell is formed and vented. The thickness of the pre-sealing edge 23 in the Z direction at the fine sealing front is a first preset thickness, and the thickness of the pre-sealing edge 23 in the Z direction after fine sealing is a second preset thickness. The first preset thickness is 1.1 to 1.5 times the second preset thickness. It should be noted that the process of processing the pre-sealed edge 23 is a pre-refined sealing process. The thickness of the pre-sealed edge 23 after fine sealing is the final target thickness. Specifically, by controlling the sealing temperature and pressure to be lower than the temperature and pressure during traditional fine sealing, the thickness of the pre-sealed edge 23 before fine sealing is 1.1 to 1.5 times the thickness after fine sealing. This makes the thickness of the PP layer on the inner side of the encapsulation film 1.1 to 1.5 times the final target thickness. Therefore, by limiting the first preset thickness to 1.1 to 1.5 times the second preset thickness, the temperature and pressure required for pre-refined sealing can be reduced, while ensuring that the pre-sealed edge 23 has a certain sealing strength, ensuring the smooth progress of processes such as liquid injection and formation, reducing the operational difficulty of subsequent fine sealing processes, and improving the production yield of battery cells.
[0045] The sealing process of the battery cell packaging structure in this embodiment is as follows: front-end process → top-side sealing → pre-sealing → electrolyte injection → pre-sealing → formation → DEGAS → sealing → subsequent processes. The top-side sealing is used to form the first sealing edge 201, the second sealing edge 202, and the third sealing edge 203. After the top-side sealing, the battery cell packaging structure forms as shown in the image. Figure 1The structure shown; pre-sealing is used to process and form pre-sealed edges 23, which, after pre-sealing, form as shown. Figure 2 The structure shown; pre-sealing is used to form the fourth edge seal 204, and after pre-sealing, it forms as shown. Figure 3 The structure shown; fine sealing is used to encapsulate based on pre-sealed edge 23 to form fine sealed edge 24, forming as shown. Figure 4 The structure shown.
[0046] The traditional battery cell sealing process is: front-end process → top-side sealing → electrolyte injection → pre-sealing → formation → DEGAS → fine sealing → subsequent processes. It does not include the pre-fine sealing step; pre-sealing is performed directly after top-side sealing and electrolyte injection, forming a process like... Figure 7 The structure shown, and with Figure 7 The structure shown undergoes formation and DEGAS processes, followed by precision sealing to form a shape as shown. Figure 4 As shown in the fine seal edge 24, during the formation and DEGAS process, since there is no isolation structure between the punched area 21 and the air bag area 22, the electrolyte in the punched area 21 is prone to contaminating the inner PP layer of the fine seal area used to form the fine seal edge 24, resulting in poor encapsulation.
[0047] In this embodiment, the cell packaging structure adds a pre-sealing step after top-side sealing and before electrolyte injection. The pre-sealing edge 23 formed by this pre-sealing differs from ordinary continuous sealing; it forms two independent sealing areas (i.e., the first pre-sealing section 231 and the second pre-sealing section 232). A channel 233 is formed between the two independent sealing areas, allowing electrolyte and gas to enter and exit. The channel 233 is biased towards the tab, ensuring that the tab side of the cell remains raised at a certain angle during electrolyte injection and subsequent formation and DEGAS processes. This does not affect the electrolyte injection process and allows for... Ensure that the electrolyte does not contaminate the unsealed channel 233; in addition, during pre-sealing, control the sealing temperature and pressure to be lower than the temperature and pressure during normal sealing, and control the PP layer thickness to be 1.1-1.5 times the final target thickness. Subsequently, continue to proceed with the normal process flow as in ordinary packaging, while keeping one side of the cell tab raised by 30°~60°. After the cell completes DEGAS sealing, trim off the excess edges. At this time, perform the final sealing, using a specially made T-shaped sealing head 3 to heat-press the PP layer to the final target thickness.
[0048] The cell packaging structure of this embodiment corresponds to a brand-new top-side sealing to fine sealing process, which solves the problem of poor fine sealing effect due to electrolyte contamination of the PP layer.
[0049] According to an embodiment of this utility model, in another aspect, a packaging device is also provided. This packaging device is used to package the aforementioned battery cell packaging structure. The packaging device includes: a device body and a precision sealing head 3. The precision sealing head 3 is connected to the device body and is used to precision seal the pre-sealed edge 23. The precision sealing head 3 includes a head body 31 and a protrusion 32 connected to the head body 31. The protrusion 32 corresponds to the channel 233. By setting the precision sealing head 3 to include the head body 31 and the protrusion 32, the precision sealing head 3 is "T"-shaped. The protrusion 32 corresponds to the channel 233. The areas on both sides of the protrusion 32 along the X direction on the precision sealing head 3 correspond to the first pre-sealed section 231 and the second pre-sealed section 232, allowing simultaneous precision sealing of the first pre-sealed section 231, the second pre-sealed section 232, and the channel 233, ensuring the smooth progress of the precision sealing process. The packaging device is a heat-sealing device. Further combined with... Figure 5 As shown, the number of precision sealing heads 3 in the packaging equipment is one pair, and the pair of precision sealing heads 3 are arranged opposite to each other to achieve heat sealing of the battery cell packaging structure.
[0050] It should be noted that since the PP layers corresponding to the first pre-sealing section 231 and the second pre-sealing section 232 have already undergone a pre-sealing process, while the channel 233 has not been sealed, the required sealing stroke for the first pre-sealing section 231 and the second pre-sealing section 232 is slightly shorter during the final sealing process, while the required sealing stroke for the channel 233 is longer, in order to ensure the sealing strength of the channel 233.
[0051] According to an embodiment of this utility model, another aspect provides a battery cell, which is manufactured from the aforementioned battery cell packaging structure. It should be noted that the battery cell packaging structure is composed of... Figure 4 The structure shown is cut to remove the airbag area 22, thus forming the structure shown. Figure 6 The battery cell shown.
[0052] 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 battery cell packaging structure, characterized in that, include: The pole assembly includes the pole assembly body and the pole tabs; The encapsulation film includes a perforated area and an air bag area spaced apart along the Y direction. The perforated area has perforations suitable for placing the electrode assembly body. A first sealing edge is provided on the side of the perforated area away from the air bag area along the Y direction. A second sealing edge and a third sealing edge are provided on both sides of the encapsulation film along the X direction. A pre-sealing edge is provided between the perforated area and the air bag area. The pre-sealing edge includes a first pre-sealing segment and a second pre-sealing segment spaced apart along the X direction. A channel is formed between the first pre-sealing segment and the second pre-sealing segment. The length of the first pre-sealing segment along the X direction is greater than the length of the second pre-sealing segment along the X direction.
2. The cell packaging structure according to claim 1, characterized in that, Along the X direction, the ratio between the length of the second pre-sealed section and the length of the first pre-sealed section ranges from 1 / 5 to 1 / 3.
3. The cell packaging structure according to claim 1, characterized in that, The dimension of the channel along the X direction ranges from 10 mm to 30 mm.
4. The cell packaging structure according to claim 1, characterized in that, The tab extends from the side of the third sealing edge on the encapsulation film, the first pre-sealed section is connected to the second sealing edge, and the second pre-sealed section is connected to the third sealing edge.
5. The cell packaging structure according to claim 4, characterized in that, The cell packaging structure is adapted to be placed at an angle to the horizontal plane, and along a direction perpendicular to the horizontal plane, the vertical distance from the third sealing edge to the horizontal plane is greater than the vertical distance from the second sealing edge to the horizontal plane.
6. The cell packaging structure according to claim 5, characterized in that, The angle between the cell packaging structure and the horizontal plane is 30°~60°.
7. The cell packaging structure according to claim 1, characterized in that, The cell packaging structure also includes a fourth sealing edge, which is located on the side of the air bag area away from the pit area along the Y direction.
8. The cell packaging structure according to any one of claims 1 to 7, characterized in that, The pre-sealing edge is suitable for fine sealing after cell formation and venting. The thickness of the pre-sealing edge in the Z direction at the fine sealing front is a first preset thickness, and the thickness of the pre-sealing edge in the Z direction after fine sealing is a second preset thickness. The first preset thickness is 1.1 to 1.5 times the second preset thickness.
9. A packaging device, characterized in that, The packaging equipment is used to package the battery cell packaging structure according to any one of claims 1 to 8, and the packaging equipment includes: Equipment body; A precision sealing head is connected to the equipment body. The precision sealing head is used to precision seal the pre-sealed edge. The precision sealing head includes a head body and a protrusion connected to the head body. The protrusion corresponds to the channel.
10. A battery cell, characterized in that, The battery cell is manufactured from the battery cell packaging structure described in any one of claims 1 to 8.