A lithium battery separator production device and its production process

Abstract

The present invention provides a production device and a production process for a lithium battery separator, which relates to the technical field of lithium battery separator production. The device includes a mixing device, an extrusion device, a longitudinal film stretching device, a transverse film stretching device, and a winding device arranged in sequence. The transverse film stretching device includes a heating box body. At one end inside the heating box body, there is a feeding guide roller. On one side of the feeding guide roller, and respectively on the upper and lower parts of the heating box body, there are multiple independent film stretching mechanisms. Between the multiple independent film stretching mechanisms, there are respectively temperature control mechanisms. On one side of the multiple temperature control mechanisms, there are respectively monitoring units. At the other end inside the heating box body, there is a discharging guide roller. Through the transverse film stretching device, the present invention monitors the passing material, retrieves the areas that need to be stretched emphatically, heats the middle of the areas that need to be stretched emphatically, and cools down both ends thereof, so that the heated areas are stretched more, and the cooled areas are stretched less, thereby avoiding the problem of thicker edges of the film and increasing the effective width.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery separator production, and specifically relates to a lithium battery separator production device and its production process. Background Art

[0002] In the production of lithium battery separators, transverse stretching is one of the necessary processes. In the prior art, after the film is stretched, the two sides of the film are thicker, there is a certain gap between the actual effective width and the width that the equipment can reach, the flatness of the two sides of the film is not good, and the utilization rate of large slitting is low. At the same time, after the film enters the extraction process, the thick edges are prone to curling. In actual production, when the separator passes through the extraction tank, after the separator is roughly leveled, a flanging operation needs to be carried out, and the purpose is to flatten the wrinkled edge material through the operation of other equipment.

[0003] The main reason is that the stretching of the film is uneven during the stretching process. In order to ensure that the film does not shift on the guide roller, the middle part of the guide roller has a slightly larger diameter than the two ends, the principle cylinder belt and the belt roller; resulting in a larger stretching amount in the middle during stretching of the film and a smaller stretching amount on both sides, resulting in thicker sides.

[0004] According to a transverse stretching and extraction process of a lithium battery separator provided by a patent document with the application number CN201710599461.9, it includes a primary transverse stretching step and an extraction step carried out in sequence. Before the separator is extracted and passed through the film, the thick edges on both sides of the separator are cut off. After cutting the edges, then carry out extraction and passing through the film. There is no curling of the thick edges, it flattens quickly, no flanging is required, the film passing efficiency is high, and it also avoids operators from coming into contact with dichloromethane for a long time during the film passing process; when the film enters the secondary transverse stretching, there are no thick edges, the effective width has a very small gap with the actual width reached by the equipment, and the effective width increases.

[0005] However, the above patent does not fundamentally solve the problem of thicker sides and cannot meet the production requirements. Summary of the Invention

[0006] In view of the above problems, the present invention provides a lithium battery separator production device and its production process, aiming to solve the technical problems that after the film is stretched, the two sides of the film are thicker, there is a certain gap between the actual effective width and the width that the equipment can reach, and the flatness of the two sides of the film is not good as mentioned in the above background art.

[0007] To achieve the above object, the present invention provides the following technical solution: A lithium battery separator production device, comprising a mixing device, an extrusion device, a longitudinal film pulling device, a transverse film pulling device, and a winding device arranged in sequence. The transverse film pulling device includes a heating box body. One end inside the heating box body is provided with a feeding guide roller. On one side of the feeding guide roller, and respectively on the upper and lower parts of the heating box body, there are multiple independent film pulling mechanisms. Between the multiple independent film pulling mechanisms, there are respectively temperature control mechanisms. On one side of the multiple temperature control mechanisms, there are respectively monitoring units. The other end inside the heating box body is provided with a discharging guide roller.

[0008] Further, one end of the heating box body is provided with a feeding port, and the other end is provided with a discharging port. On both sides of the heating box body, there are respectively multiple film pulling chutes, and outside the multiple film pulling chutes, there are respectively closed covers.

[0009] Further, the independent film pulling mechanism includes a film pulling motor. The film pulling motor is arranged on one side of the heating box body. The execution end of the film pulling motor is coaxially connected to a film pulling drive gear. The film pulling drive gear is meshed with a film pulling control gear. The film pulling control gear is coaxially connected to the middle of a film pulling linkage shaft. The two ends of the film pulling linkage shaft are respectively rotatably connected to a rotating shaft bracket. Multiple rotating shaft brackets are all arranged on one side of the heating box body. The two ends of the film pulling linkage shaft are respectively coaxially connected to a linkage bevel gear. Multiple linkage bevel gears are respectively meshed with a film pulling unit. Multiple film pulling units are symmetrically arranged on both sides of the heating box body. Multiple film pulling units are symmetrically arranged at both ends of a film pulling roller. The two ends of the film pulling roller are respectively slidably connected to both sides of the heating box body. The two ends of the film pulling roller are respectively rotatably connected to one end of the temperature control mechanism.

[0010] Further, the film pulling unit includes a driven bevel gear. The driven bevel gear is meshed with the linkage bevel gear. The driven bevel gear is coaxially connected to the upper end of a film pulling lead screw. The two ends of the film pulling lead screw are respectively rotatably connected to a lead screw bracket. Multiple lead screw brackets are all arranged on one side of the heating box body. The middle of the film pulling lead screw is threadedly connected to a film pulling control block. One side of the film pulling control block is rotatably connected to one end of the film pulling roller.

[0011] Further, the temperature control mechanism includes multiple heating units. The multiple heating units are arranged oppositely. The two ends of the multiple heating units are respectively arranged in the middle of a driven unit. In the middle of the driven unit, above and below the multiple heating units, there are respectively multiple cooling units. The two ends of the multiple driven units are respectively rotatably connected to the two ends of the multiple independent film pulling mechanisms.

[0012] Further, the heating unit includes a plurality of electric heating rods, which are linearly arranged and can independently control the heating temperature. The plurality of electric heating rods are arranged inside the reflection cover. Heating fixing blocks are respectively arranged at both ends of the reflection cover, and the plurality of heating fixing blocks are respectively arranged in the middle of the plurality of driven units.

[0013] Further, the driven unit includes an upper driven block, which is rotatably connected to one end of the independent film pulling mechanism in its upper middle part. A driven slider is arranged on one side of the upper driven block. One end of the driven slider is slidably connected to a driven upper rod. The lower end of the driven upper rod is arranged at one end of an upper fixing block. A plurality of temperature control fixing rods are arranged on the bottom surface of the upper fixing block. The lower ends of the plurality of temperature control fixing rods are provided with a lower fixing block. One end of the lower fixing block is arranged at the upper end of a driven lower rod. The lower end of the driven lower rod is arranged at the upper part of a lower driven block, and the lower driven block is rotatably connected to one end of the independent film pulling mechanism in its lower middle part.

[0014] Further, the cooling unit includes a plurality of semiconductor refrigeration chips, which are linearly arranged and can independently control the heating temperature. The plurality of semiconductor refrigeration chips are arranged on one side of a heat dissipation housing. Cooling fans are respectively arranged at both ends of the heat dissipation housing. Both ends of the heat dissipation housing are respectively connected to external air extraction devices through hoses. Cooling fixing blocks are respectively arranged at both ends of the heat dissipation housing, and the plurality of cooling fixing blocks are respectively arranged in the middle of the plurality of driven units.

[0015] Further, the monitoring unit includes a plurality of industrial cameras, which are linearly arranged. The plurality of industrial cameras are arranged inside the heating box body through monitoring brackets.

[0016] According to the above technical solution, a lithium battery separator production process will also be provided, including the following steps:

[0017] S1. Feeding: After pre-treating raw materials such as PP and pore-forming agent according to the formula in the mixing device, they are transported to the extrusion device;

[0018] S2. Casting: A PP cast film with a high β-crystal content and good β-crystal morphological uniformity is obtained by outputting through the extrusion device;

[0019] S3. Longitudinal stretching: The cast film is longitudinally stretched at a certain temperature through the longitudinal film pulling device, and pores are formed by using the characteristic that β-crystals are prone to form pores under tensile stress;

[0020] S4. Transverse stretching: The material is transversely stretched at a higher temperature through the transverse film pulling device to expand the pores and improve the uniformity of the pore size distribution at the same time;

[0021] S5. Final shaping and winding: The diaphragm is heat-treated at high temperature through a winding device to reduce its thermal shrinkage rate and improve its dimensional stability.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] The passing materials are monitored by a transverse film stretching device to retrieve the areas that need to be stretched emphatically. The middle part of the areas that need to be stretched emphatically is heated, and the two ends are cooled, so that the heated areas are stretched more, and the cooled areas are stretched less, thus avoiding the problem of thicker edges of the film and increasing the effective width. Description of the Drawings

[0024] Figure 1 is a schematic diagram of the external structure of the present invention;

[0025] Figure 2 is a schematic sectional view of the internal structure of the present invention;

[0026] Figure 3 is a schematic front view of the sectional internal structure of the present invention;

[0027] Figure 4 is a schematic diagram of the structure of the independent film stretching mechanism of the present invention;

[0028] Figure 5 is a schematic diagram of the structure of the temperature control mechanism of the present invention;

[0029] Figure 6 is a schematic exploded view of the structure of the temperature control mechanism of the present invention;

[0030] Figure 7 is a schematic diagram of the structure of the heating unit of the present invention;

[0031] Figure 8 is a schematic diagram of the structure of the driven unit of the present invention;

[0032] Figure 9 is a schematic sectional view of the structure of the cooling unit of the present invention;

[0033] Figure 10 is a schematic diagram of the structure of the monitoring unit of the present invention.

[0034] In the figure: 1. Heating box; 11. Feeding port; 12. Discharging port; 13. Film pulling chute; 14. Enclosure; 2. Feeding guiding roller; 3. Independent film pulling mechanism; 31. Film pulling motor; 32. Film pulling driving gear; 33. Film pulling control gear; 34. Film pulling linkage shaft; 35. Rotating shaft bracket; 36. Linkage bevel gear; 37. Film pulling unit; 371. Driven bevel gear; 372. Film pulling lead screw; 373. Lead screw bracket; 374. Film pulling control block; 38. Film pulling roller; 4. Temperature control mechanism; 41. Heating unit; 411. Electric heating rod; 412. Reflector; 413. Heating fixing block; 42. Driven unit; 421. Upper driven block; 422. Driven sliding block; 423. Upper driven rod; 424. Upper fixing block; 425. Temperature control fixing rod; 426. Lower fixing block; 427. Lower driven rod; 428. Lower driven block; 43. Cooling unit; 431. Semiconductor refrigeration chip; 432. Heat dissipation housing; 433. Heat dissipation fan; 434. Cooling fixing block; 5. Monitoring unit; 51. Industrial camera; 52. Monitoring bracket; 6. Discharging guiding roller. Embodiment

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as a limitation to the present invention.

[0036] Next, the embodiments of the present invention will be described according to its overall structure.

[0037] For the embodiment, please refer with emphasis to Figures 1-3 , a lithium battery separator production device, including a mixing device, an extrusion device, a longitudinal film pulling device, a transverse film pulling device, and a winding device arranged in sequence. The transverse film pulling device includes a heating box 1. One end inside the heating box 1 is provided with a feeding guiding roller 2. On one side of the feeding guiding roller 2, and on the upper and lower parts of the heating box 1, a plurality of independent film pulling mechanisms 3 are respectively provided. Between the plurality of independent film pulling mechanisms 3, a temperature control mechanism 4 is respectively provided. On one side of the plurality of temperature control mechanisms 4, a monitoring unit 5 is respectively provided. The other end inside the heating box 1 is provided with a discharging guiding roller 6. One end of the heating box 1 is provided with a feeding port 11, and the other end is provided with a discharging port 12. On both sides of the heating box 1, a plurality of film pulling chutes 13 are respectively opened. Outside the plurality of film pulling chutes 13, enclosures 14 are respectively provided. The film stretched by the longitudinal film pulling device enters the heating box 1 from the feeding port 11, bypasses the feeding guiding roller 2, and then passes through the plurality of independent film pulling mechanisms 3 and the plurality of temperature control mechanisms 4 at intervals, and then bypasses the discharging guiding roller 6 and is output from the discharging port 12.

[0038] For the embodiment, please refer with emphasis to Figure 4, the independent film pulling mechanism 3 includes a film pulling motor 31, the film pulling motor 31 is arranged on one side of the heating box body 1, the execution end of the film pulling motor 31 is coaxially connected to a film pulling driving gear 32, the film pulling driving gear 32 is engaged and connected to a film pulling control gear 33, the film pulling control gear 33 is coaxially connected to the middle of a film pulling linkage shaft 34, both ends of the film pulling linkage shaft 34 are respectively rotationally connected to a rotating shaft bracket 35, and a plurality of the rotating shaft brackets 35 are all arranged on one side of the heating box body 1. Both ends of the film pulling linkage shaft 34 are respectively coaxially connected to a linkage bevel gear 36, and a plurality of the linkage bevel gears 36 are respectively engaged and connected to film pulling units 37. A plurality of the film pulling units 37 are symmetrically arranged on both sides of the heating box body 1, and a plurality of the film pulling units 37 are symmetrically arranged at both ends of a film pulling roller 38. Both ends of the film pulling roller 38 are respectively slidably connected to both sides of the heating box body 1, and both ends of the film pulling roller 38 are respectively rotationally connected to one end of the temperature control mechanism 4. The film pulling unit 37 includes a driven bevel gear 371, the driven bevel gear 371 is engaged and connected to the linkage bevel gear 36, the driven bevel gear 371 is coaxially connected to the upper end of a film pulling lead screw 372, both ends of the film pulling lead screw 372 are respectively rotationally connected to a lead screw bracket 373, and a plurality of the lead screw brackets 373 are all arranged on one side of the heating box body 1. The middle of the film pulling lead screw 372 is threadedly connected to a film pulling control block 374, and one side of the film pulling control block 374 is rotationally connected to one end of the film pulling roller 38. This design drives the film pulling driving gear 32 to rotate through the film pulling motor 31, and then drives two linkage bevel gears 36 to rotate simultaneously through the film pulling control gear 33 and the film pulling linkage shaft 34. Furthermore, through the engagement and cooperation of two driven bevel gears 371 with two linkage bevel gears 36 respectively, two film pulling lead screws 372 are driven to rotate. Through the threaded cooperation of two film pulling lead screws 372 with two film pulling control blocks 374 respectively, two film pulling control blocks 374 and the film pulling roller 38 are driven to move up and down.

[0039] For the embodiment, please refer to Figures 5-9 , the temperature control mechanism 4 includes a plurality of heating units 41, a plurality of the heating units 41 are arranged oppositely, both ends of a plurality of the heating units 41 are respectively arranged in the middle of a driven unit 42, and a plurality of cooling units 43 are respectively arranged above and below the middle of the driven unit 42 and both ends of a plurality of the heating units 41. Both ends of a plurality of the driven units 42 are respectively rotationally connected to both ends of a plurality of the independent film pulling mechanisms 3. This design heats both sides of the area that needs to be stretched emphatically through two heating units 41, making it easier to stretch, and cools both sides of both ends of the area that needs to be stretched emphatically through four cooling units 43, making its toughness slightly higher and facilitating the stretching at the heated part.

[0040] The heating unit 41 includes a plurality of electric heating rods 411. The plurality of electric heating rods 411 are arranged linearly and can control the heating temperature separately. The plurality of electric heating rods 411 are arranged inside the reflector 412. Heating fixing blocks 413 are respectively arranged at both ends of the reflector 412. The plurality of heating fixing blocks 413 are respectively arranged in the middle of the plurality of driven units 42. This design precisely heats the areas that need to be stretched emphatically, especially both sides of the film, through the plurality of electric heating rods 411 arranged linearly.

[0041] The driven unit 42 includes an upper driven block 421. The upper driven block 421 is rotatably connected to one end of the independent film pulling mechanism 3 in its upper middle part. A driven slider 422 is arranged on one side of the upper driven block 421. One end of the driven slider 422 is slidably connected to a driven upper rod 423. The lower end of the driven upper rod 423 is arranged at one end of an upper fixing block 424. A plurality of temperature control fixing rods 425 are arranged on the bottom surface of the upper fixing block 424. The lower ends of the plurality of temperature control fixing rods 425 are provided with a lower fixing block 426. One end of the lower fixing block 426 is arranged at the upper end of a driven lower rod 427. The lower end of the driven lower rod 427 is arranged at the upper part of a lower driven block 428. The lower driven block 428 is rotatably connected to one end of the independent film pulling mechanism 3 in its lower middle part. This design enables the two driven blocks in the driven unit 42 to move respectively following the upper and lower independent film pulling mechanisms 3, so that the two temperature control fixing rods 425 always remain parallel to the film, that is, the distances between the two heating units 41 and the four cooling units 43 and the film always remain unchanged.

[0042] The cooling unit 43 includes a plurality of semiconductor refrigeration chips 431. The plurality of semiconductor refrigeration chips 431 are arranged linearly and can control the heating temperature separately. The plurality of semiconductor refrigeration chips 431 are arranged on one side of a heat dissipation housing 432. Heat dissipation fans 433 are respectively arranged at both ends of the heat dissipation housing 432. Both ends of the heat dissipation housing 432 are respectively connected to an external air extraction device through hoses. Cooling fixing blocks 434 are respectively arranged at both ends of the heat dissipation housing 432. The plurality of cooling fixing blocks 434 are respectively arranged in the middle of the plurality of driven units 42. This design cools the film by facing the refrigerating surface of the semiconductor refrigeration chips 431 towards the film, and the heat dissipation side faces the inside of the heat dissipation housing 432. The heat is output to the external air extraction device through the heat dissipation fans 433 at both ends via the hoses.

[0043] For the embodiment, please refer emphatically to Figure 10 The monitoring unit 5 includes a plurality of industrial cameras 51. The plurality of industrial cameras 51 are arranged linearly. The plurality of industrial cameras 51 are arranged inside the heating box body 1 through monitoring brackets 52. This design monitors the aperture and hole density on the film through the plurality of industrial cameras 51 and divides the areas that need to be stretched emphatically.

[0044] Embodiment, a production process for a lithium battery separator, comprising the following steps:

[0045] S1. Feeding: After pre-treating raw materials such as PP and pore-forming agent according to the formula in the mixing device, they are transported to the extrusion device;

[0046] S2. Casting: Output through the extrusion device to obtain a PP cast film with a high β-crystal content and good β-crystal morphological uniformity;

[0047] S3. Longitudinal stretching: The cast film is longitudinally stretched at a certain temperature through a longitudinal film stretching device, and pores are formed by utilizing the characteristic that β-crystals are prone to form pores under tensile stress;

[0048] S4. Transverse stretching: The material is transversely stretched at a higher temperature through a transverse film stretching device to expand the pores and improve the uniformity of the pore size distribution at the same time;

[0049] S5. Fixing and winding: The separator is heat-treated at a high temperature through a winding device to reduce its thermal shrinkage rate and improve its dimensional stability. This design passes.

[0050] Operating principle of the transverse film stretching device: First, the film stretched by the longitudinal film stretching device enters from the feed port 11, bypasses the feed guiding roller 2, and then passes through multiple independent film stretching mechanisms 3 and multiple temperature control mechanisms 4 at intervals, and then bypasses the discharge guiding roller 6 and is output from the discharge port 12; After bypassing the feed guiding roller 2, the first monitoring unit 5 monitors the pore diameter and pore density on the film through multiple industrial cameras 51, and divides the key stretching area; After the film bypasses the first independent film stretching mechanism 3 and passes through the first temperature control mechanism 4, two heating units 41 heat both sides of the area that needs to be stretched emphatically, making it easier to stretch, and four cooling units 43 cool both ends of the area that needs to be stretched emphatically, making its toughness slightly higher and facilitating stretching at the heated area; At the same time, the first independent film stretching mechanism 3 and the second independent film stretching mechanism 3 drive the film stretching driving gear 32 to rotate through the film stretching motor 31, and then drive two linkage bevel gears 36 to rotate simultaneously through the film stretching control gear 33 and the film stretching linkage shaft 34. Furthermore, two driven bevel gears 371 are respectively engaged with the two linkage bevel gears 36 to drive two film stretching lead screws 372 to rotate. Through the threaded cooperation of the two film stretching lead screws 372 and two film stretching control blocks 374 respectively, two film stretching control blocks 374 and the film stretching roller 38 move up and down, forming a pulling force to stretch the film; In this way, it passes through multiple monitoring units 5, multiple independent film stretching mechanisms 3 and multiple temperature control mechanisms 4, and finally bypasses the discharge guiding roller 6 and is output from the discharge port 12.

[0051] Although embodiments of the present invention have been shown and described, the specific embodiments are merely explanations of the present invention and not limitations thereof. The specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions and variations that do not make creative contributions to the embodiments as needed, but as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. A lithium battery separator production device, comprising a mixing device, an extrusion device, a longitudinal film stretching device, a transverse film stretching device, and a winding device arranged in sequence, Characterized in that: The transverse film stretching device includes a heating box body (1). One end inside the heating box body (1) is provided with a feeding guide roller (2). On one side of the feeding guide roller (2), multiple independent film stretching mechanisms (3) are respectively provided on the upper and lower parts of the heating box body (1). Temperature control mechanisms (4) are respectively arranged between the multiple independent film stretching mechanisms (3). Monitoring units (5) are respectively arranged on one side of the multiple temperature control mechanisms (4). The other end inside the heating box body (1) is provided with a discharging guide roller (6); The temperature control mechanism (4) includes multiple heating units (41). The multiple heating units (41) are arranged oppositely. Both ends of the multiple heating units (41) are respectively arranged in the middle of the driven unit (42). Multiple cooling units (43) are respectively arranged above and below the middle of the driven unit (42) and the multiple heating units (41). Both ends of the multiple driven units (42) are respectively rotatably connected to both ends of the multiple independent film stretching mechanisms (3); The driven unit (42) includes an upper driven block (421). The upper driven block (421) is rotatably connected to one end of the independent film stretching mechanism (3) in its upper middle part. One side of the upper driven block (421) is provided with a driven slider (422). One end of the driven slider (422) is slidably connected to a driven upper rod (423). The lower end of the driven upper rod (423) is arranged at one end of an upper fixing block (424). The bottom surface of the upper fixing block (424) is provided with multiple temperature control fixing rods (425). The lower ends of the multiple temperature control fixing rods (425) are provided with a lower fixing block (426). One end of the lower fixing block (426) is arranged at the upper end of a driven lower rod (427). The lower end of the driven lower rod (427) is arranged at the upper part of a lower driven block (428). The lower driven block (428) is rotatably connected to one end of the independent film stretching mechanism (3) in its lower middle part.

2. The lithium battery separator production device according to claim 1, Characterized in that: One end of the heating box body (1) is provided with a feeding port (11), and the other end is provided with a discharging port (12). Multiple film stretching chutes (13) are respectively opened on both sides of the heating box body (1). Sealing covers (14) are respectively arranged outside the multiple film stretching chutes (13).

3. The lithium battery separator production device according to claim 1, Characterized in that: The independent film pulling mechanism (3) includes a film pulling motor (31). The film pulling motor (31) is arranged on one side of the heating box body (1). The execution end of the film pulling motor (31) is coaxially connected to a film pulling drive gear (32). The film pulling drive gear (32) is meshed and connected to a film pulling control gear (33). The film pulling control gear (33) is coaxially connected to the middle of a film pulling linkage shaft (34). The two ends of the film pulling linkage shaft (34) are respectively rotatably connected to a rotating shaft bracket (35). A plurality of the rotating shaft brackets (35) are all arranged on one side of the heating box body (1). The two ends of the film pulling linkage shaft (34) are respectively coaxially connected to a linkage bevel gear (36). A plurality of the linkage bevel gears (36) are respectively meshed and connected to a film pulling unit (37). A plurality of the film pulling units (37) are symmetrically arranged on both sides of the heating box body (1). A plurality of the film pulling units (37) are symmetrically arranged at both ends of a film pulling roller (38). The two ends of the film pulling roller (38) are respectively slidably connected to both sides of the heating box body (1). The two ends of the film pulling roller (38) are respectively rotatably connected to one end of the temperature control mechanism (4).

4. The lithium battery separator production equipment according to claim 3, characterized in that: The film pulling unit (37) includes a driven bevel gear (371). The driven bevel gear (371) is meshed and connected to the linkage bevel gear (36). The driven bevel gear (371) is coaxially connected to the upper end of a film pulling lead screw (372). The two ends of the film pulling lead screw (372) are respectively rotatably connected to a lead screw bracket (373). A plurality of the lead screw brackets (373) are all arranged on one side of the heating box body (1). The middle of the film pulling lead screw (372) is threadedly connected to a film pulling control block (374). One side of the film pulling control block (374) is rotatably connected to one end of the film pulling roller (38).

5. The lithium battery separator production equipment according to claim 1, characterized in that: The heating unit (41) includes a plurality of electric heating rods (411). The plurality of electric heating rods (411) are arranged in a linear arrangement and the heating temperature can be controlled separately. The plurality of electric heating rods (411) are arranged inside a reflector (412). The two ends of the reflector (412) are respectively provided with heating fixing blocks (413). The plurality of heating fixing blocks (413) are respectively arranged in the middle of the plurality of driven units (42).

6. The lithium battery separator production equipment according to claim 1, characterized in that: The cooling unit (43) includes a plurality of thermoelectric cooling chips (431). The plurality of thermoelectric cooling chips (431) are arranged linearly and can be individually controlled for heating temperature. The plurality of thermoelectric cooling chips (431) are disposed on one side of a heat dissipation housing (432). Heat dissipation fans (433) are respectively provided at both ends of the heat dissipation housing (432). External air extraction devices are respectively connected to both ends of the heat dissipation housing (432) through hoses. Cooling fixing blocks (434) are respectively provided at both ends of the heat dissipation housing (432). The plurality of cooling fixing blocks (434) are respectively disposed in the middle of the plurality of driven units (42).

7. An apparatus for producing a lithium battery separator according to claim 1, wherein: The monitoring unit (5) includes a plurality of industrial cameras (51). The plurality of industrial cameras (51) are arranged linearly and are disposed inside the heating box (1) through monitoring brackets (52).

8. A production process for a lithium battery separator, using the apparatus for producing a lithium battery separator according to any one of claims 1-7, wherein: It includes the following steps: S1. Feeding: After pre-treating the PP and pore-forming agent raw materials according to the formula in the mixing device, they are transported to the extrusion device; S2. Casting: A PP cast film with a high β-crystal content and good β-crystal morphological uniformity is obtained by outputting through the extrusion device; S3. Longitudinal stretching: The cast film is longitudinally stretched at a certain temperature by a longitudinal film stretching device, and pores are formed by using the characteristic that β-crystals are prone to form pores under tensile stress; S4. Transverse stretching: The material is transversely stretched at a higher temperature by a transverse film stretching device to expand the pores and improve the uniformity of the pore size distribution at the same time; S5. Shaping and winding: The separator is heat-treated at a high temperature by a winding device to reduce its thermal shrinkage rate and improve dimensional stability.

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