Battery cell coating apparatus and coating method

Abstract

The application provides a kind of electric core film wrapping device and film wrapping method, electric core film wrapping device includes lower film wrapping component, and upper film wrapping component located above lower film wrapping component, lower film wrapping component includes lower film folding piece, lower pressing plate and lower elastic unit, lower pressing plate is slidably arranged above lower film folding piece, lower film folding piece has lower film folding knife separately arranged at both sides of electric core, when upper film folding piece continues to move downward, lower pressing plate slides downward and compresses lower elastic unit, so that lower film folding knife penetrates through lower pressing plate and folds both sides of lower film body upward into upper flange, upper flange is connected to the outside of lower flange through adhesive layer.The electric core film wrapping device provided by the application can first wrap the upper film body on the electric core, then wrap the lower film body on the electric core, and bond the lower film body on both sides of the upper film body by heating the upper film body and the lower film body at both ends of the electric core to realize the film wrapping of the electric core, thereby improving the film wrapping efficiency of the electric core.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power battery processing, in particular to a battery cell film wrapping device. BACKGROUND

[0002] In the process of battery cell production, Mylar film needs to be wrapped outside the battery cell, and the whole wrapping process is relatively complex, which specifically includes the following steps:

[0003] First step: first place the Mylar film on the jig, then place the battery cell on the Mylar film, and then install the positive terminal plate into the positive electrode of the battery cell;

[0004] Second step: connect and fix the Mylar film with the positive terminal plate and the negative top cover bottom through bottom hot melting;

[0005] Third step: the film wrapping robot clamps one side corner of the Mylar film and folds the Mylar film by 180° to wrap the battery cell;

[0006] Fourth step: connect and fix the Mylar film with the positive terminal plate and the negative top cover top through top hot melting;

[0007] Fifth step: the upper pressing knife folds the film downward, and the lower pressing knife folds the film upward to seal the Mylar film;

[0008] Sixth step: connect and fix the Mylar film with the positive terminal plate and the negative top cover side through side hot melting;

[0009] Seventh step: seven C-shaped finger glue is pasted to fix and seal.

[0010] The above seven steps are the general steps of wrapping the Mylar film for the battery cell, and the process beat is generally 6-8 seconds. As can be seen, the current battery cell film wrapping process has the problems of complex process, many actions in the process, and many stations. In addition, due to the long production beat, the production capacity of the battery cell is seriously limited.

[0011] In addition, many devices are used in the process of wrapping the battery cell, including the circulating jig, the film wrapping machine, the upper hot melting mechanism, the lower hot melting mechanism, the side hot melting mechanism, the upper pressing knife mechanism, the lower pressing knife mechanism, and the glue sticking machine, etc., so that the cost of the whole battery cell film wrapping is high. SUMMARY

[0012] Therefore, the present application aims to provide a battery cell film wrapping device to improve the film wrapping efficiency of the battery cell.

[0013] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0014] An electric cell film-wrapping device for wrapping an upper film body and a lower film body on an electric cell, the electric cell film-wrapping device comprising a lower film-wrapping assembly and an upper film-wrapping assembly above the lower film-wrapping assembly, wherein,

[0015] The lower film-wrapping assembly comprises a lower film folding member, a lower pressing plate and a lower elastic unit, the lower pressing plate is arranged above the lower film folding member for supporting the lower film body and the electric cell on the lower film body, the lower film folding member has lower film folding knives arranged on both sides of the electric cell and capable of penetrating through the lower pressing plate, and the lower elastic unit is arranged between the lower film folding member and the lower pressing plate, and the lower film body is provided with adhesive layers on both sides of the electric cell;

[0016] The upper film-wrapping assembly comprises an upper film folding member, an upper pressing plate and an upper elastic unit, the upper pressing plate is arranged above the upper film folding member and capable of adsorbing the upper film body, the upper film folding member has upper film folding knives arranged on both sides of the electric cell and capable of penetrating through the upper pressing plate, and the upper elastic unit is arranged between the upper film folding member and the upper pressing plate;

[0017] When the upper film folding member is driven to move downward by external force, the upper film body can be placed on the upper surface of the electric cell, the upper elastic unit is compressed to store energy, and the upper film folding knives are driven to penetrate through the upper pressing plate to fold the two sides of the upper film body downward into lower flanges;

[0018] When the upper film folding member continues to move downward, the lower pressing plate can slide downward and compress the lower elastic unit, so that the lower film folding knives can penetrate through the lower pressing plate to fold the two sides of the lower film body upward into upper flanges, and the upper flanges are connected to the outer sides of the lower flanges through the adhesive layers to wrap the upper film body and the lower film body on the electric cell;

[0019] The upper film body and the lower film body can be wrapped on end covers at both ends of the electric cell by being heated.

[0020] Further, the elastic modulus of the upper elastic unit is smaller than that of the lower elastic unit.

[0021] Further, the upper film folding knives are arranged in multiple along the length direction of the electric cell.

[0022] The lower film folding knives are arranged in multiple along the length direction of the electric cell, and the lower film folding knives and the upper film folding knives are staggered.

[0023] Further, the adhesive layers and the upper film folding knives are staggered.

[0024] Further, the outer surface of the upper film folding knives is provided with an anti-adhesive layer.

[0025] Further, the upper pressing plate is guided to slide on the upper folding film piece.

[0026] And / or, the lower pressing plate is guided to slide on the lower folding film piece.

[0027] Further, a plurality of hot melt heads are arranged around the circumference of the end cover are further included.

[0028] The upper film body and the lower film body are wrapped on the end cover due to being heated by the hot melt heads.

[0029] Further, the upper elastic unit and / or the lower elastic unit includes a plurality of springs.

[0030] Further, a cavity is formed in the upper pressing plate, a bottom surface of the upper pressing plate is provided with a plurality of through holes in communication with the cavity, the cavity can be in communication with an external negative pressure part, and the upper film body is adsorbed on the upper pressing plate through the through holes.

[0031] Compared with the prior art, the present application has the following advantages:

[0032] The electric core film wrapping device can wrap the upper film body on the electric core first, then wrap the lower film body on the electric core, and then bond the lower film body on both sides of the upper film body, and heat the upper film body and the lower film body at both ends of the electric core to achieve the film wrapping of the electric core, thereby improving the film wrapping efficiency of the electric core and reducing the production cost.

[0033] In addition, another object of the present application is to provide an electric core film wrapping method for wrapping the upper film body and the lower film body on the electric core, the electric core film wrapping method comprising the following steps:

[0034] Placing the electric core on the lower film body;

[0035] Pressing the upper film body against the upper surface of the electric core, then folding the two side portions of the upper film body downward to form lower flanges, and making the lower flanges adhere to the two sides of the electric core and remain;

[0036] Folding the two side portions of the lower film body upward to form upper flanges, and making the upper flanges adhere to the outer side of the lower flanges;

[0037] Heating the upper film body and the lower film body around the end cover at both ends of the electric core, so that the upper film body and the lower film body are wrapped on the end cover.

[0038] The electric core film wrapping method can wrap the upper film body on the electric core first, then wrap the lower film body on the electric core, and then bond the lower film body on the upper film body, which is conducive to achieving the film wrapping of the electric core and improving the film wrapping efficiency of the electric core. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which form a part of this application, are intended to provide further understanding of the application and are incorporated herein in their entirety, and together with the general description of the application and the detailed description of specific embodiments of the application, explain the application. In the drawings:

[0040] Figure 1 Structure schematic view of the electric core film coating device according to the embodiment of the application in one perspective view;

[0041] Figure 2 Structure schematic view of the electric core film coating device according to the embodiment of the application in another perspective view;

[0042] Figure 3 Structure schematic view of the electric core film coating device according to the embodiment of the application in one perspective view;

[0043] Figure 4 Structure schematic view of the electric core film coating device according to the embodiment of the application in another perspective view;

[0044] Figure 5 Structure schematic view of the upper and lower folding film pieces according to the embodiment of the application;

[0045] Figure 6 Structure schematic view of the electric core film coating device according to the embodiment of the application in a film coating state;

[0046] Figure 7 Structure schematic view of the upper and lower film bodies according to the embodiment of the application in a folding state;

[0047] Figure 8 Structure schematic view of the electric core film coating device according to the embodiment of the application in a hot melting state.

[0048] Explanation of reference signs:

[0049] 1. Upper folding film piece; 101. Upper folding film knife; 102. Connecting column;

[0050] 2. Upper pressing plate; 201. Upper guide column; 202. Upper limiting block; 203. Upper knife passing hole;

[0051] 3. Upper film body;

[0052] 4. Electric core; 401. End cover;

[0053] 5. Lower pressing plate; 501. Lower knife passing hole;

[0054] 6. Lower folding film piece; 601. Lower folding film knife; 602. Lower limiting block; 603. Lower guide column;

[0055] 7. Lower film body; 701. Adhesive layer;

[0056] 8, upper elastic unit; 9, lower elastic unit; 10, hot melting head. DETAILED DESCRIPTION

[0057] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0058] In the description of the present application, it should be noted that if the terms indicating the orientation or position relationship such as "upper", "lower", "inner", "back" and the like appear, they are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, if the terms "first", "second" and the like appear, they are also only for the purpose of description and cannot be understood as indicating or implying relative importance.

[0059] The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0060] Embodiment one

[0061] The present embodiment relates to a kind of electric core film wrapping device, for the upper film body 3 and lower film body 7 are wrapped in electric core 4 outside.The overall constitution is, this electric core film wrapping device includes lower film wrapping component, and the upper film wrapping component located above lower film wrapping component.

[0062] Wherein, lower film wrapping component includes lower film folding piece 6, lower pressing plate 5 and lower elastic unit 9.Lower pressing plate 5 is slidably arranged above lower film folding piece 6, for supporting lower film body 7 and the electric core 4 located on lower film body 7, lower film folding piece 6 has lower film folding knife 601 that can be arranged through lower pressing plate 5 and is separately arranged at the two sides of electric core 4.Lower elastic unit 9 is arranged between lower film folding piece 6 and lower pressing plate 5, and lower film body 7 is provided with adhesive layer 701 located at the two sides of electric core 4.

[0063] Upper film wrapping component includes upper film folding piece 1, upper pressing plate 2 and upper elastic unit 8.Upper pressing plate 2 is slidably arranged above upper film folding piece 1, and can adsorb upper film body 3, upper film folding piece 1 has upper film folding knife 101 that can be arranged through upper pressing plate 2 and is separately arranged at the two sides of electric core 4, and upper elastic unit 8 is arranged between upper film folding piece 1 and upper pressing plate 2.

[0064] When the upper folding film piece 1 in the embodiment is driven to move downward by external force, the upper film body 3 can be pressed on the upper surface of the battery cell 4, the upper elastic unit 8 is compressed to store energy, and the upper folding film knife 101 is driven to pass through the upper pressing plate 2, and the upper folding film knife 101 folds the two sides of the upper film body 3 downward to form lower flanges. When the upper folding film piece 1 continues to move downward, the lower pressing plate 5 can slide downward and compress the lower elastic unit 9, so that the lower folding film knife 601 can pass through the lower pressing plate 5 and fold the two sides of the lower film body 7 upward to form upper flanges, and the upper flanges are connected to the outer sides of the lower flanges through the adhesive layer 701, so as to wrap the upper film body 3 and the lower film body 7 around the battery cell 4. The upper film body 3 and the lower film body 7 can be wrapped around the end cover 401 at both ends of the battery cell 4 due to heating.

[0065] Based on the overall introduction as above, an exemplary structure of the battery cell film wrapping device in the embodiment is shown in Figure 1 and Figure 2 The structure of the lower film wrapping assembly will be described first. The lower folding film piece 6 in the embodiment has a rectangular plate structure, and the lower folding film knives 601 are arranged on both sides of the lower folding film piece 6 and protrude from the top of the lower folding film piece 6. As preferred, the lower folding film knives 601 on each side are arranged in multiple numbers along the length direction of the lower folding film piece 6. The lower pressing plate 5 is guided to slide above the lower folding film piece 6 and also has a rectangular shape, which is simple in structure and easy to arrange and implement.

[0066] The lower pressing plate 5 is supported above the lower folding film piece 6 by the elastic force of the lower elastic unit 9. The middle part of the upper surface of the lower pressing plate 5 is provided with a lower film body 7 placement area, and the lower film body 7 is specifically laid on the lower film body 7 placement area. The battery cell 4 to be wrapped is placed on the upper surface of the lower film body 7. As preferred, the lower film body 7 placement area is located in the middle part of the lower pressing plate 5 and in the middle part of the two lower folding film pieces 6, which is beneficial to improve the stability of the lower film wrapping assembly in use. In addition, the two ends of the lower film body 7 and the end cover 401 of the battery cell 4 are located outside the lower pressing plate 5, which is beneficial to the heating of the upper film body 3 and the lower film body 7 wrapped around the end cover 401 of the battery cell 4 by the hot melting head 10, so as to facilitate the wrapping of the lower film body 7 and the lower film body 7 on the end cover 401.

[0067] In the embodiment, the lower folding film knives 601 on both sides of the lower folding film piece 6 are respectively arranged corresponding to the two sides of the battery cell 4, and the lower pressing plate 5 is provided with lower knife passing holes 501 allowing the lower folding film knives 601 to pass through. After the lower folding film knives 601 pass through the lower knife passing holes 501, the lower film body 7 on both sides of the battery cell 4 can be folded upward by 90° to form the upper flanges.

[0068] As a preferred implementation, under the elastic force of the lower elastic unit 9, the lower folding film knife 601 in the initial state is retracted in the corresponding lower cutting hole 501, which facilitates the timely emergence of the lower folding film knife 601 from the lower cutting hole 501, thereby forming the upper turning edge, and further facilitating the improvement of the efficiency of the battery cell 4 film wrapping.

[0069] To improve the stability of the lower pressing plate 5 in use, the lower pressing plate 5 in the embodiment guides and slides on the lower folding film member 6. Specifically, as shown in FIGS. 3 and Figure 4 , two downwardly extending lower guide columns 603 are provided on the bottom of the lower pressing plate 5 and pass through the lower folding film member 6, and a lower limiting block 602 is provided at the bottom end of each guide column. The lower pressing plate 5 guides and slides on the lower folding film member 6 through the two lower guide columns 603, and is limited from being removed from the lower folding film member 6 by the abutment of the lower limiting block 602 with the bottom of the lower folding film member 6. The structure of the lower guide column 603 and the lower limiting block 602 is simple and easy to process and form, and has good use effect. Of course, the number of lower guide columns 603 and lower limiting blocks 602 can also be increased or decreased according to the use requirements during specific implementation.

[0070] The lower elastic unit 9 in the embodiment includes a plurality of lower springs provided between the lower pressing plate 5 and the lower folding film member 6. As a preferred implementation, the lower springs in the embodiment are two, which are respectively sleeved on the lower guide columns 603 and abut against the lower pressing plate 5 and the lower folding film member 6 at both ends. Here, by sleeving the lower springs on the lower guide columns 603, the stability of the lower springs in use is improved, and the product of the lower springs is mature, easy to install, and has good use effect.

[0071] The structure of the upper film wrapping assembly in the embodiment is shown in FIGS. 3 and Figure 5 The upper folding film member 1 is also a rectangular plate structure, which is located directly above the lower pressing plate 5. The upper folding film knives 101 are provided on both sides of the upper folding film member 1 and extend out of the bottom of the upper folding film member 1. As a preferred, the upper folding film knives 101 on both sides are a plurality of upper folding film knives 101 arranged at intervals along the length direction of the upper folding film member 1, and the upper folding film knives 101 and the lower folding film knives 601 are arranged in a staggered manner in the length direction of the battery cell 4. In this way, when the upper folding film knives 101 abut against the outside of the upper turning edge, the abutment of the lower folding film knives 601 against the outside of the lower turning edge will not interfere with each other, thereby improving the connection effect and the adhesion between the upper turning edge and the lower turning edge.

[0072] In addition, in order to apply external force to the upper pressing plate 2, two connection columns 102 are also provided on the top of the upper pressing plate 2 and arranged at intervals. The power output end of the external driving device can be connected with the connection column 102, so as to apply external force to the upper folding film knife 101, thereby driving the upper folding film member 1 to move upward and downward.

[0073] In this embodiment, the upper pressure plate 2 slides below the upper folded film member 1 and is also rectangular. A placement area for the upper film body 3 is formed on the lower surface of the upper pressure plate 2, where the upper film body 3 can be adsorbed. As a preferred embodiment, a cavity is formed within the upper pressure plate 2, and the bottom surface of the upper pressure plate 2 has multiple through holes communicating with the cavity. The cavity can communicate with an external negative pressure unit, and the upper film body 3 is adsorbed onto the upper pressure plate 2 through the through holes. Here, the structure of the cavity and through holes is simple, easy to process and form, and works well with the negative pressure unit to adsorb the upper film body 3 effectively. Figure 1 and Figure 2 As shown, the upper membrane 3 and the lower membrane 7 are placed in the upper membrane 3 placement area and are in one-to-one correspondence, with their two ends also slightly extending out of the upper pressure plate 2.

[0074] In this embodiment, the upper folding film blades 101 located on both sides of the upper folding film member 1 are respectively provided on both sides of the battery cell 4. The upper pressure plate 2 is provided with upper passing holes 203 that allow each upper folding film blade 101 to pass through freely. After the upper folding film blade 101 passes through the upper passing holes 203, it can fold the upper film body 3 located on both sides of the battery cell 4 downward by 90° to form the aforementioned lower folded edge.

[0075] As a preferred embodiment, under the elastic force of the upper elastic unit 8, the upper folding blade 101 in the initial state retracts into the corresponding upper through-blade hole 203. This facilitates the upper folding blade 101 to pass through the upper through-blade hole 203 in a timely manner, thereby forming a lower folded edge, which in turn helps to improve the efficiency of the cell 4 coating.

[0076] To improve the stability of the upper pressure plate 2, in this embodiment, the upper pressure plate 2 is guided and slidably mounted on the upper folding film member 1. Specifically, as follows: Figure 2 As shown, the upper pressure plate 2 has two upwardly extending upper guide posts 201 at its top end, which pass through the upper folding film member 1. Each upper guide post 201 has an upper limit block 202 at its top. The upper pressure plate 2 slides on the upper folding film member 1 guided by the two upper guide posts 201, and the upper pressure plate 2 is prevented from detaching from the upper folding film member 1 by the contact between the upper limit block 202 and the top of the upper folding film member 1. The structure of the upper guide posts 201 and the upper limit block 202 is simple, easy to process and form, and has good performance. Of course, in specific implementations, the number of upper guide posts 201 and upper limit blocks 202 can be adjusted according to usage requirements.

[0077] In this embodiment, the upper elastic unit 8 includes multiple upper springs disposed between the upper pressure plate 2 and the upper folding film member 1. As a preferred embodiment, two upper springs are used, each sleeved on the upper guide post 201, with both ends abutting against the upper pressure plate 2 and the upper folding film member 1, respectively. Here, by sleeved on the upper guide post 201, the stability of the upper springs during use is improved, and the upper springs are mature products, easy to install, and have good performance.

[0078] In this embodiment, when the upper pressing plate 2 presses the upper film body 3 on the battery cell 4 to fold the film, the upper spring is in a compressed state, and the lower spring is in an initial state, and the lower pressing plate 5 remains stationary. Only when the upper flange is formed and the upper pressing plate 2 continues to press the battery cell 4 downward, the lower spring will be compressed and deformed. Therefore, in specific implementation, the elastic modulus of the upper elastic unit 8 is less than the elastic modulus of the lower elastic unit 9.

[0079] In addition, the adhesive layer 701 in this embodiment can be two continuous strips as shown in Figure 1 In specific implementation, the adhesive layer 701 can be made of double-sided tape or sprayed glue. Since the upper flange is adhered to the outside of the lower flange, such a continuous adhesive layer 701 will be adhered to the outside of the upper film folding knife 101. But this adhesion will not affect the extrusion of the upper film folding knife 101, and when the upper film folding knife 101 is extruded between the upper flange and the lower flange, the upper film body 3 and the lower film body 7 will not be damaged.

[0080] To prevent the adhesive layer 701 from being partially adhered to the upper film folding knife 101, thereby affecting the film folding effect of the upper film folding knife 101, the outer surface of the upper film folding knife 101 can also be provided with an anti-adhesive layer in this embodiment. In specific implementation, a layer of Teflon can be provided on the outer surface of the upper film folding knife 101 to improve the anti-adhesive effect and wear resistance of the upper film folding knife 101.

[0081] It should be noted that, in addition to the two continuous strip structures as shown in Figure 2 , the adhesive layer 701 can also be staggered with the upper film folding knife 101. That is, the adhesive layer 701 is discontinuously arranged in multiple sections. In this way, when the upper flange is adhered to the lower flange, the adhesive layer 701 will not contact the upper film folding knife 101, thereby preventing the upper film folding knife 101 from being contaminated, and at the same time, the extrusion effect of the upper film folding knife 101 from between the upper flange and the lower flange is better.

[0082] In this embodiment, as shown in Figure 8 , the battery cell film wrapping device further comprises a plurality of hot melt heads 10 arranged circumferentially around the end cover 401, and the hot melt heads 10 are used to heat the upper film body 3 and the lower film body 7, so as to wrap the upper film body 3 and the lower film body 7 around the end cover 401.

[0083] The electric core film wrapping device described in the embodiment is used, first, the upper film body 3 is adsorbed on the upper film body 3 placing area, then the connecting column 102 is used to apply downward external force to the upper folding film piece 1, and the whole upper film wrapping assembly is driven to move downward. After the upper pressing plate 2 presses the upper film body 3 on the surface of the electric core 4, the external force continues to drive the upper folding film piece 1 to move downward, so that the upper elastic unit 8 is compressed and stored, the upper folding film knife 101 can pass through the upper knife hole 203 downward under the action of the upper elastic unit 8, and the upper film body 3 is folded downward by 90° on both sides to form a lower flange, so that the lower flange is attached to both sides of the electric core 4, and the upper folding film knife 101 keeps extruding the lower flange, ensuring that the upper flange is attached to both sides of the electric core 4. At this time, the upper pressing plate 2 cancels the adsorption of the upper film body 3.

[0084] Then continue to press the upper folding film piece 1 downward, the lower elastic unit 9 is extruded by the lower pressing plate 5, the lower elastic unit 9 is compressed and stored, and the two lower folding film knives 601 on the lower folding film piece 6 pass through the lower pressing plate 5, and the two sides of the lower film body 7 are folded upward by 90° to form an upper flange, and the adhesive layer 701 on the upper flange is attached to the outside of the lower flange, and the lower folding film knife 601 keeps extruding the upper flange, ensuring that the upper flange and the lower flange are attached to both sides of the electric core 4. The electric core film wrapping device at this time is shown in Figure 6 and Figure 7 .

[0085] Then a plurality of hot melting heads 10 are arranged around the end cover 401, the upper film body 3 and the lower film body 7 around the end cover 401 are heated by the hot melting heads 10, so that the upper film body 3 and the lower film body 7 are wrapped outside the end cover 401. Finally, an upward external force is applied to the connecting column 102, the upper elastic unit 8 releases the stored energy and pushes the upper pressing plate 2, so that the upper folding film knife 101 returns to the upper pressing plate 2, until the upper pressing plate 2 is separated from the upper film body 3 and returns to the initial state.

[0086] At the same time, the lower elastic unit 9 also releases the stored energy and pushes the lower pressing plate 5 downward, so that the lower folding film knife 601 returns to the lower pressing plate 5, thereby releasing the restriction on both sides of the electric core 4, completing the film wrapping of the electric core 4, and finally the electric core 4 wrapped with the film is taken off from the lower pressing plate 5.

[0087] The electric core film wrapping device in the embodiment can first wrap the upper film body 3 on the electric core 4, then wrap the lower film body 7 on the electric core 4, and then wrap the upper film body 3 and the lower film body 7 on both ends of the electric core 4 by the lower film body 7, so as to realize the film wrapping of the electric core 4, thereby improving the film wrapping efficiency of the electric core 4 and reducing the production cost.

[0088] Embodiment two

[0089] The embodiment relates to a cell film wrapping method for wrapping an upper film body 3 and a lower film body 7 on a cell 4 respectively. The cell film wrapping method comprises the following steps.

[0090] The cell 4 is placed on the lower film body 7, the upper film body 3 is pressed on the upper surface of the cell 4, the two side portions of the upper film body 3 are folded downward to form lower flanges, and the lower flanges are attached to the two sides of the cell 4, and the state of the lower flanges is maintained by two upper film folding knives 101.

[0091] The two side portions of the lower film body 7 are folded upward to form upper flanges, the upper flanges are attached to the outer sides of the lower flanges, and the state of the upper flanges is maintained by two lower film folding knives 601. The upper film body 3 and the lower film body 7 around the end cover 401 of the two ends of the cell 4 are heated, the upper film body 3 and the lower film body 7 are wrapped on the end portion of the cell 4, and the film wrapping of the cell 4 is completed.

[0092] The cell film wrapping method provided in the embodiment is used for wrapping the upper film body 3 on the cell 4 first, then wrapping the lower film body 7 on the cell 4, and attaching the lower film body 7 to the upper film body 3, which is beneficial to realize the film wrapping of the cell 4 and improve the film wrapping efficiency of the cell 4.

[0093] The above only describes the preferred embodiment of the application, and is not used to limit the application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the application should be included in the protection scope of the application.

Claims

1. An electric cell film wrapping device for wrapping an upper film body (3) and a lower film body (7) around an electric cell (4), characterized in that: the electric cell film wrapping device comprises a lower film wrapping assembly and an upper film wrapping assembly above the lower film wrapping assembly, wherein the lower film wrapping assembly comprises a lower film folding piece (6), a lower pressing plate (5) and a lower elastic unit (9), the lower pressing plate (5) is arranged above the lower film folding piece (6) and is used for supporting the lower film body (7) and the electric cell (4) on the lower film body (7), the lower film folding piece (6) has lower film folding knives (601) arranged on both sides of the electric cell (4) and capable of penetrating through the lower pressing plate (5), and the lower elastic unit (9) is arranged between the lower film folding piece (6) and the lower pressing plate (5), and the lower film body (7) is provided with an adhesive layer (701) on both sides of the electric cell (4); the upper film wrapping assembly comprises an upper film folding piece (1), an upper pressing plate (2) and an upper elastic unit (8), the upper pressing plate (2) is arranged above the upper film folding piece (1) and is capable of adsorbing the upper film body (3), the upper film folding piece (1) has upper film folding knives (101) arranged on both sides of the electric cell (4) and capable of penetrating through the upper pressing plate (2), and the upper elastic unit (8) is arranged between the upper film folding piece (1) and the upper pressing plate (2); when the upper film folding piece (1) is driven to move downward under external force, the upper film body (3) can be pressed on the upper surface of the electric cell (4), the upper elastic unit (8) is compressed to store energy, and the upper film folding knives (101) penetrate through the upper pressing plate (2) to fold down the two sides of the upper film body (3) into lower flanges; when the upper film folding piece (1) continues to move downward, the lower pressing plate (5) can slide downward and compress the lower elastic unit (9), so that the lower film folding knives (601) can penetrate through the lower pressing plate (5) and fold up the two sides of the lower film body (7) into upper flanges, and the upper flanges are connected to the outer sides of the lower flanges through the adhesive layer (701) to wrap the upper film body (3) and the lower film body (7) around the electric cell (4); the upper film body (3) and the lower film body (7) can be wrapped around end covers (401) at both ends of the electric cell (4) by being heated.

2. The electric cell film wrapping device according to claim 1, characterized in that: the elastic modulus of the upper elastic unit (8) is smaller than the elastic modulus of the lower elastic unit (9).

3. The electric cell film wrapping device according to claim 1, characterized in that: the upper film folding knives (101) are a plurality of upper film folding knives arranged along the length direction of the electric cell (4); the lower film folding knives (601) are a plurality of lower film folding knives arranged along the length direction of the electric cell (4), and the lower film folding knives (601) and the lower film folding knives (601) are arranged alternately.

4. The electric cell film wrapping device according to claim 1, characterized in that: the adhesive layer (701) and the upper film folding knives (101) are arranged alternately. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 5. The battery cell film wrapping device according to claim 1, characterized in that: the outer surface of the upper film folding knife (101) is provided with an anti-sticking layer.

6. The battery cell film wrapping device according to claim 1, characterized in that: the upper pressing plate (2) is guided to slide on the upper film folding member (1); and / or, the lower pressing plate (5) is guided to slide on the lower film folding member (6).

7. The battery cell film wrapping device according to claim 1, characterized in that: further comprising a plurality of hot melt heads arranged circumferentially around the end cover (401); the upper film body (3) and the lower film body (7) are wrapped around the end cover (401) due to being heated by the hot melt heads.

8. The battery cell film wrapping device according to claim 1, characterized in that: the upper elastic unit (8) and / or the lower elastic unit (9) comprises a plurality of springs.

9. The battery cell film wrapping device according to any one of claims 1 to 8, characterized in that: a cavity is formed in the upper pressing plate (2), the bottom surface of the upper pressing plate (2) is provided with a plurality of through holes in communication with the cavity, the cavity is capable of communicating with an external negative pressure part, and the upper film body (3) is adsorbed on the upper pressing plate (2) through the through holes.

10. An electrode core film wrapping method for wrapping an upper film body (3) and a lower film body (7) on an electrode core (4), characterized by, The battery cell film wrapping method is based on the battery cell film wrapping device according to any one of claims 1 to 9, and comprises the following steps: placing the battery cell (4) on the lower film body (7); pressing the upper film body (3) against the upper surface of the battery cell (4), then folding the two side portions of the upper film body (3) downward to form lower flanges, and making the lower flanges adhere to the two sides of the battery cell (4) and remain; folding the two side portions of the lower film body (7) upward to form upper flanges, and making the upper flanges adhere to the outside of the lower flanges; heating the upper film body (3) and the lower film body (7) around the end cover (401) of the battery cell (4), so that the upper film body (3) and the lower film body (7) wrap around the end cover (401).

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