CN115954522A

CN115954522A - Core shaping system and method

Info

Publication number: CN115954522A
Application number: CN202310019915.6A
Authority: CN
Inventors: 陈筠; 穆建华; 李龙
Original assignee: Sunwoda Electric Vehicle Battery Co Ltd
Current assignee: Sunwoda Electric Vehicle Battery Co Ltd
Priority date: 2023-01-06
Filing date: 2023-01-06
Publication date: 2023-04-11

Abstract

The application relates to the technical field of batteries, and discloses a roll core shaping system and a method, wherein the roll core shaping system comprises a stretching device, a rolling device and a hot pressing device, the stretching device is arranged at an upstream station of the rolling device or is arranged at the same station with the rolling device, the rolling device comprises a rolling platform, a roll rod and a rolling traction mechanism, and the rolling traction mechanism is connected to the roll rod and drives the roll rod to move so as to roll a roll core; the hot pressing device is arranged at a downstream station of the rolling device. The stretching, rolling and hot pressing of the roll core are realized through the stretching device, the rolling device and the hot pressing device, the stretching and shaping can be performed firstly before the hot pressing and shaping are performed after the roll core is wound, then the rolling and shaping can be performed, the problems that the winding stress release problem exists in the roll core and the isolation film and/or the free motion state exists in the isolation film can be effectively solved, and the abnormity that the follow-up pole piece or the isolation film is folded, the roll core is deformed or shifted and the like can be avoided.

Description

Core shaping system and method

Technical Field

The application relates to the technical field of battery manufacturing, in particular to a winding core shaping system and method.

Background

In the production of lithium batteries, the main modes for manufacturing the winding core include a winding mode and a lamination mode. The winding production mode is to form a basic winding core by winding the positive plate, the isolating film and the negative plate by a winding needle. In the current production and manufacturing process flow, after positive and negative pole pieces and an isolation film are wound, a winding core is directly transferred to a hot press for hot pressing and shaping, however, after a winding needle is separated from a winding needle after winding is completed, the pole pieces and the isolation film of the winding core have the release of winding stress or the pole pieces and the isolation film have the free motion state, so that the folding deformation or the displacement is very easy to occur, particularly the pole pieces are easy to occur near the corners of the winding core and the first pole piece at the innermost circle, the pole pieces are deformed integrally, the interface performance of a battery is invalid, even the positive and negative poles are in direct contact to generate short circuit, and the safety performance of the battery is invalid.

Disclosure of Invention

The present application is directed to solving at least one of the problems in the prior art. Therefore, the application provides a winding core shaping system and method, which can effectively solve the problems of wrinkling of a battery core pole piece/isolation film, deformation of a winding core and displacement of the pole piece.

Roll up core plastic system according to this application embodiment, including stretching device, roll-in device and hot press unit, wherein: the stretching device is arranged at an upstream station of the rolling device or arranged at the same station with the rolling device, and is used for stretching the cylindrical winding core along the radial direction of the cylindrical winding core; the rolling device comprises a rolling platform, a roller rod and a rolling traction mechanism, the rolling platform is provided with a first plane for bearing the winding core stretched by the stretching device, and the rolling traction mechanism is connected to the roller rod and drives the roller rod to move along a direction parallel to the first plane so as to roll the stretched winding core; the hot pressing device is arranged at a downstream station of the rolling device and is used for receiving the rolled core rolled by the rolling device and carrying out hot pressing.

The core shaping system of the embodiment of the application has the following beneficial effects at least: through stretching device, roll-in device and hot press unit realize rolling up the tensile of core, roll-in and hot pressing, and can roll up before the core is convoluteed and is accomplished back hot pressing setting, tensile plastic earlier, then roll-in plastic, can effectively solve the problem that pole piece and barrier film have coiling stress release problem and/or barrier film to have the free motion state in rolling up the core, avoid follow-up pole piece or barrier film fold, roll up the core and warp or shift etc. unusually, improve battery interfacial properties and security performance inefficacy problem, promote the electric core quality.

According to some embodiments of the application, the stretching device comprises a stretching traction mechanism and two support members, wherein the stretching traction mechanism is connected with at least one of the support members and can enable the two support members to move away from or towards each other along the rolling direction of the roller rod.

According to some embodiments of the application, the stretching device further comprises a mounting platform, a limiting part and two stretching traction mechanisms, wherein the stretching traction mechanisms are movably connected to the mounting platform, the stretching traction mechanisms are respectively connected to the supporting part, the limiting part is connected to the mounting platform, is positioned on one side of the stretching traction mechanisms, which deviates from each other, and is used for abutting against the stretching traction mechanisms.

According to some embodiments of the application, the support piece is a long rod-shaped structure, and two one sides of the support pieces which deviate from each other are provided with arc surfaces.

According to some embodiments of the application, the inside of the support piece is provided with an air flow channel, one side of the support piece, which deviates from each other, is provided with a plurality of air outlets, the air outlets are communicated with the air flow channel along the radial direction of the air flow channel, and the air flow channel is suitable for being connected with an air source.

According to some embodiments of the application, the rolling device comprises two roller rods and two rolling traction mechanisms, each roller rod is respectively connected to one rolling traction mechanism, the rolling traction mechanism can adjust the stroke of the roller rods, and the stroke comprises a first stroke of the roller rods moving in a direction parallel to the rolling platform and a second stroke of the roller rods moving in a direction perpendicular to the rolling platform.

According to some embodiments of the application, hot press unit includes heating mechanism, first clamp plate, second clamp plate and clamp plate actuating mechanism, heating mechanism is used for heating first clamp plate with at least one of second clamp plate, first clamp plate with the second clamp plate sets up in opposite directions, first clamp plate is used for bearing roll core, clamp plate actuating mechanism connects and orders about the second clamp plate moves with the pressfitting between primary importance and second place roll core, works as the second clamp plate is located the primary importance, first clamp plate with minimum distance L has between the second clamp plate.

According to some embodiments of the present application, the hot pressing device further comprises a limiting mechanism, the limiting mechanism is connected to the pressing plate driving mechanism, and the limiting mechanism is used for limiting a stroke of the pressing plate driving mechanism driving the second pressing plate to move.

According to some embodiments of the application, one side of the first pressing plate and one side of the second pressing plate, which face each other, are respectively connected with a pair of shaping molds, two pairs of shaping molds are aligned with each other, the shaping molds on the first pressing plate protrude out of the first pressing plate to a height H1, the shaping molds on the second pressing plate protrude out of the second pressing plate to a height H2, wherein H1+ H2 is equal to or less than L.

According to some embodiments of the application, a fixed surface is arranged on the fixing mold, the fixed surface is an arc surface, and the fixing surfaces in the fixing mold face each other and can surround to form a semicircular arc surface.

According to the application, the method for reshaping the winding core comprises the following steps:

stretching: stretching the cylindrical winding core after the winding needle is separated to a set stroke along the radial direction, and stretching the cylindrical winding core into the winding core with the width direction along the stretching direction;

rolling: rolling the winding core along the width direction of the stretched winding core;

hot pressing: and carrying out hot-press shaping on the rolled core.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

Fig. 1 is a schematic structural diagram of a core shaping system according to an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a stretching apparatus in an embodiment of the present application;

FIG. 3 is a schematic view of the stretching assembly of the present application in use to stretch a core;

FIG. 4 is a schematic structural view of a rolling device in an embodiment of the present application;

FIG. 5 is a schematic view of a roll bar rolling a core in a stretched state;

FIG. 6 is a schematic structural diagram of a hot press apparatus according to an embodiment of the present disclosure;

fig. 7 is a schematic diagram of a structure of a setting die in a hot press apparatus.

Reference numerals:

the device comprises a stretching device 100, a stretching traction mechanism 101, a support member 102, an installation platform 103, a limiting member 104, an arc surface 105 and an air outlet 106;

the device comprises a rolling device 200, a rolling platform 201, a roller rod 202, a vertical traction mechanism 203 and a horizontal traction mechanism 204;

the hot-pressing device comprises a hot-pressing device 300, a heating mechanism 301, a first pressing plate 302, a second pressing plate 303, a shaping mold 304, a shaping surface 305, a pressing plate driving mechanism 306 and a limiting mechanism 307;

conveyor 400, core 500, side 501.

Detailed Description

The conception and the resulting technical effects of the present application will be clearly and completely described in conjunction with the embodiments below, so that the objects, features and effects of the present application can be fully understood. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all embodiments, and other embodiments obtained by those skilled in the art without inventive efforts based on the embodiments of the present application belong to the protection scope of the present application.

In the description of the embodiments of the present application, if an orientation description is referred to, for example, the orientations or positional relationships indicated by "upper", "lower", "front", "rear", "left", "right", and the like are based on the orientations or positional relationships shown in the drawings, it is only for convenience of description and simplification of description, but not to indicate or imply that the referred apparatus or device must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present application.

In the description of the embodiments of the present application, if a feature is referred to as being "disposed", "fixed", "connected", or "mounted" to another feature, it can be directly disposed, fixed, or connected to the other feature or indirectly disposed, fixed, connected, or mounted to the other feature. In the description of the embodiments of the present application, if "a number" is referred to, it means one or more, if "a plurality" is referred to, it means two or more, if "greater than", "less than" or "more than" is referred to, it is understood that the number is not included, and if "greater than", "lower" or "inner" is referred to, it is understood that the number is included. If reference is made to "first" or "second", this should be understood to distinguish between features and not to indicate or imply relative importance or to implicitly indicate the number of indicated features or to implicitly indicate the precedence of the indicated features.

In the current production process flow, after positive and negative pole pieces and an isolation film are wound, a winding core is directly transferred to a hot press for hot pressing and shaping. The production process mode easily causes the fold deformation of the pole piece/isolating membrane and the free state displacement of the pole piece, and particularly easily causes the pole piece/isolating membrane to be folded and deformed at the corner of a winding core (between a large plane of the winding core and a corner arc transition area, the area has height difference and uneven stress of the pole piece) and the pole piece which is firstly folded at the innermost circle, so the performance of the battery cell is restricted by the manufacturing process flow, and the deformation problem of the battery cell with thicker thickness after being wound is particularly serious.

The embodiment of the application provides a roll up core plastic system, including stretching device, roll-in device and hot press unit, can effectively solve electric core pole piece/barrier film fold, roll up the problem that core warp and pole piece shifted to improve electric core interface performance and security performance. Embodiments of the present application are described below with reference to the accompanying drawings:

fig. 1 is the structural schematic diagram of the core shaping system of this application embodiment, refer to fig. 1 to fig. 3, the core shaping system of this application embodiment, including stretching device 100, roll-in device 200 and hot press unit 300, stretching device 100 is used for drawing the traction to the core 500 of rolling after the completion of convoluteing, will roll up core 500 from the circular or oval tube-shape after the coiling along the tensile distance of setting for of radial direction, form relatively flat structure, realize roll core 500 preliminary plastic so that follow-up roll-in, roll-in device 200 is used for carrying out the roll-in plastic to the core 500 of rolling after the stretch-out plastic, hot press unit 300 is used for carrying out the hot pressing design to the core 500 of rolling after the roll-in.

In this embodiment, after the winding core 500 is formed by winding, the winding core 500 is of a cylindrical structure, and the winding needle is left in the middle to pull out the axle center hole left.

The rolling device 200 comprises a rolling platform 201, a roller rod 202 and a rolling traction mechanism, the rolling platform 201 is provided with a first plane, the first plane is used for bearing a winding core 500 stretched by the stretching device 100, the roller rod 202 is parallel to the rolling platform 201, the rolling traction mechanism is connected to the roller rod 202, and drives the roller rod 202 to move along a direction parallel to the first plane so as to roll the stretched winding core 500.

The stretching device 100 may be disposed at an upstream station of the rolling device 200, or the stretching device 100 may be disposed at the same station as the rolling device 200. The term "station" refers to each position that a workpiece (or an assembly unit) occupies together with a movable part of a jig or a device relative to a fixed part of the device after being once clamped in order to perform a certain process. "process" refers to a portion of the process of all the steps that are performed continuously as the workpiece is machined or assembled at one station. In the embodiment of the present application, the winding core 500 may perform the stretching process by the stretching device 100 and perform the rolling process by the rolling device 200. The stretching device 100 may be disposed at an upstream station of the rolling device 200, so that the core 500 occupies different positions of a fixed portion (such as a frame or a ground) of the core shaping system during the stretching process and the rolling process, and the core 500 may be rolled by transferring to the rolling platform 201 after stretching; in other embodiments, the stretching device 100 may be disposed at the same station as the rolling device 200, so that the core 500 occupies the same position of the fixed part (such as the frame or the ground) of the core shaping system during the stretching process and the rolling process, for example, the core 500 may be stretched and rolled in sequence above the rolling platform 201, and may be rolled without transferring after stretching.

The hot pressing device 300 is disposed at a downstream station of the rolling device 200, and is configured to receive the roll core 500 rolled by the rolling device 200 and perform hot pressing. Therefore, the stretching, rolling and hot pressing of the winding core 500 are realized through the stretching device 100, the rolling device 200 and the hot pressing device 300, after the winding of the winding core 500 is completed, the stretching and shaping are firstly carried out, the winding core 500 is stretched from a wound round or oval cylinder shape along the radial direction for a set distance, a certain width is formed in the stretching direction, and two opposite large surfaces are formed in the thickness direction perpendicular to the stretching direction, so that the winding core 500 is stretched to form a relatively flat structure, the primary shaping of the winding core 500 is realized, then the rolling, shaping and hot pressing and shaping are carried out, the problem that the winding stress release exists in a pole piece and an isolation film in the winding core 500 and/or the problem that the isolation film has a free motion state can be effectively solved, and the abnormity that the following pole piece or isolation film folds, the winding core 500 deforms or shifts and the like is avoided.

In some embodiments, referring to fig. 2, the stretching apparatus 100 includes a stretching traction mechanism 101 and two support members 102, the support members 102 are adapted to be inserted into an axial hole of the winding core 500, the stretching traction mechanism 101 is connected to at least one support member 102, and is capable of moving the two support members 102 away from or toward each other along a rolling direction of the roller rod 202, so that the winding core 500 is stretched and pulled by driving the movement of the support members 102, the free state displacement of the pole pieces can be avoided by stretching traction while the pole pieces and the isolation film release the winding stress, so as to realize the primary shaping of the winding core 500, and then the rolling apparatus 200 is used for rolling, thereby effectively eliminating the wrinkle deformation problem of the pole pieces/isolation film.

In some embodiments, the stretching device 100 further includes a mounting platform 103 and a limiting member 104, and the limiting member 104 is connected to the mounting platform 103, so as to limit the maximum distance between the two supporting members 102 by limiting the stretching traction mechanism 101. For example: the stretching device 100 can include two stretching traction mechanisms 101, the two stretching traction mechanisms 101 are movably connected to the mounting platform 103 respectively, each stretching traction mechanism 101 is connected to the supporting piece 102 respectively and drives the supporting piece 102 to move respectively, so as to stretch the winding core 500, the limiting pieces 104 include 2 pieces, the two pieces are connected to the mounting platform 103 respectively, and the two pieces are located on one side where the stretching traction mechanisms 101 deviate from each other, so that the stretching traction mechanisms 101 are supported and held at set positions to limit the maximum stroke of the two stretching traction mechanisms 101 moving towards the direction of the deviation from each other, thereby limiting the maximum distance between the two supporting pieces 102, and avoiding damaging the winding core 500.

Alternatively, the stretching device 100 may include a stretching traction mechanism 101, where the stretching traction mechanism 101 is connected to one of the supporting members 102 and is configured to drive the supporting member 102 to move relative to the other supporting member 102, and the stretching device 100 further includes a stopper 104, where the stopper 104 is connected to the mounting platform 103 and is located on a side of the stretching traction mechanism 101 facing away from the other supporting member 102 and is configured to abut against the stretching traction mechanism 101 at a set position so as to limit a maximum stroke of the stretching traction mechanism 101 moving away from the other supporting member 102, so as to limit a maximum distance between the two supporting members 102 and avoid damaging the winding core 500.

The stretching traction mechanism 101 may be a linear motion mechanism such as a linear motor or an air cylinder, and has a base body and an output portion, the base body is mounted on the mounting platform 103, the corresponding support member 102 is driven to move by the movement of the output portion, and the limiting member 104 may be a block-shaped or column-shaped protruding member fixedly connected to the mounting platform 103 in the above manner, and may be configured to abut against the output portion of the stretching traction mechanism 101, so as to achieve mechanical limiting. Of course, the stretching traction mechanism 101 may also limit the maximum distance between the supporting members 102 by presetting its own stroke, and the limiting member 104 may serve as a mechanical limiting member, thereby improving the safety of the mechanism. Servo motor can be selected for use to the power component among the tensile drive mechanism 101, and servo motor has higher control accuracy, improves the control accuracy of corresponding support piece 102 stroke from this, can effectively avoid support piece 102 to stretch that roll core 500 stroke is too big and damage roll core 500 to and avoid support piece 102 to stretch the stroke undersize and lead to rolling core 500 plastic effect poor, influence the problem of follow-up roll-in.

In some embodiments, the supporting member 102 is a long rod-shaped structure, and is suitable for being inserted into the innermost circle of the winding core 500 along the axial direction of the winding core 500, the stretching and pulling mechanism 101 is connected to the supporting member 102 through a connecting member, so that the winding core 500 after winding can be stretched and pulled along the radial direction by driving the supporting member 102 to move away from each other, and the two supporting members 102 are provided with arc surfaces 105 at sides facing away from each other, and the arc surfaces 105 can be provided on the supporting member 102 in various ways, for example: the support member 102 may be a rod-like structure having a circular or oval cross-section, such that the outer side has a circular arc surface 105; alternatively, the supporting member 102 may be a rod-shaped structure having a cross section of an approximately polygonal shape, corners of which are rounded, thereby forming a circular arc surface 105 at the corners. Thus, damage to the pole piece or separator from the stretching process support 102 can be reduced. The end of the support 102 along the axial direction may be provided with a rounded corner, so as to reduce the damage to the pole piece or the isolation film when the support 102 moves axially.

The support member 102 may be of a relatively flat rod-like structure, that is, the size of the support member 102 in the stretching direction is larger than the size perpendicular to the stretching direction, and the flat rod-like structure is adopted, so that the contact area between the side surface of the support member 102 in the stretching direction and the inner ring of the winding core 500 can be reduced while the strength of the support member 102 is ensured, thereby reducing the gap between the pole pieces at the corner of the inner ring of the winding core 500, reducing the lithium ion transmission distance, and reducing the lithium deposition caused by the longer lithium ion transmission distance.

In addition, the supporting member 102 may be made of an abrasion-resistant material or the outer surface of the supporting member 102 is provided with a protective layer made of an abrasion-resistant material, which may be a polymer plastic material or a teflon material, so as to effectively reduce the abrasion of the supporting member 102 and the replacement cost.

In some embodiments, an air flow channel is arranged inside the support member 102, a plurality of air outlets 106 are arranged on the sides of the support member 102, which face away from each other, the air outlets 106 are communicated with the air flow channel along the radial direction of the air flow channel, and the air flow channel is suitable for being connected to an air source, so that the air source is connected when the support member 102 is recovered, the adsorption of the support member 102 to a pole piece or an isolation film can be effectively reduced by blowing air through the air outlets 106, the support member 102 is ensured to be smoothly separated from the winding core 500, and the probability of the pole piece or the isolation film being wrinkled or damaged is reduced.

In some embodiments, the rolling device 200 includes two roller rods 202 and two rolling traction mechanisms, the roller rods 202 are used for rolling the winding core 500, each roller rod 202 is connected to one rolling traction mechanism, the roller rods 202 are parallel to the rolling platform 201, so as to ensure the stress uniformity of the winding core 500, and the rolling traction mechanisms can adjust the stroke of the roller rods 202, thereby rolling the stretched winding core 500. Wherein, the stroke of the roller rod 202 includes a first stroke of the roller rod 202 moving in a direction parallel to the rolling platform 201, and a second stroke of the roller rod 202 moving in a direction perpendicular to the rolling platform 201. Therefore, the position of the roller rod 202 relative to the winding core 500 can be adjusted through the first stroke, the relative position between the two roller rods 202 can be adjusted, the position of the roller rod 202 pressed towards the winding core 500 can be adjusted through the second stroke, the rolling thickness of the winding core 500 can be determined, the roller rod 202 can roll the winding core 500 in the direction parallel to the rolling platform 201 through adjustment of the first stroke, and the first stroke and the second stroke can be reasonably adjusted according to the required stretching width of the winding core 500 and the rolling thickness.

The rolling traction mechanism can comprise a vertical traction mechanism 203 and a horizontal traction mechanism 204, wherein the vertical traction mechanism 203 is used for driving the roller rod 202 to move along the direction perpendicular to the rolling platform 201, the horizontal traction mechanism 204 is used for driving the roller rod 202 to move along the direction parallel to the rolling platform 201, the second stroke of the roller rod 202 is adjusted by starting and stopping the vertical traction mechanism 203, damage caused by overvoltage of a winding core 500 is avoided, the first stroke of the roller rod 202 is adjusted by starting and stopping the horizontal traction mechanism 204, a set distance is kept between the two roller rods 202, and collision damage is avoided. Both the vertical traction mechanism 203 and the horizontal traction mechanism 204 can adopt servo motors, and the servo motors have higher control precision, so that the corresponding position precision of the roller rod 202 is improved.

In the solution in which the stretching device 100 is arranged at a station upstream of the rolling device 200, the stretching device 100 may be provided with a transfer mechanism connected to the stretching traction mechanism 101 for moving the stretching traction mechanism 101 together with the support 102 above the rolling platform 201, whereby the stretching traction of the core 500 may be maintained before rolling. From this, during the roll-in, can make support piece 102 break away from book core 500 after roll rod 202 moves to setting for the position along the direction that is on a parallel with roll-in platform 201, roll core 500 can keep by the tensile state at the first half section of roll-in process from this, support piece 102 breaks away from roll core 500 back roll rod 202 and continues the roll-in to the border of rolling core 500, to improving the edge 500 pole piece inner circle of roll core and crumpling deformation and pole piece location and showing the effect, and be favorable to rolling core 500 corners and stereotype, this roll-in process accessible roll-in drive mechanism stops control and realizes. The transfer mechanism may be implemented by a mechanism for transferring an article, which is commonly used in a mechanized apparatus, such as a linear motor, a multi-axis robot arm, and the like.

The hot press device 300 can further apply stress to the winding core 500 under the conditions of high temperature and high pressure after the winding core 500 finishes the procedures of stretching traction and rolling shaping, so that the winding core 500 is shaped, the winding core 500 is prevented from deforming and shifting, and the bonding effect of the pole piece and the isolating membrane can be cured. In some embodiments, the hot pressing device 300 includes a heating mechanism 301, a first pressing plate 302, a second pressing plate 303, and a pressing plate driving mechanism 306, the heating mechanism 301 is configured to heat at least one of the first pressing plate 302 and the second pressing plate 303, the first pressing plate 302 and the second pressing plate 303 are disposed opposite to each other, the first pressing plate 302 is configured to carry the winding core 500, the pressing plate driving mechanism 306 is connected to and drives the second pressing plate 303 to move between a first position and a second position to press the winding core 500, and when the second pressing plate 303 is located at the first position, the first pressing plate 302 and the second pressing plate 303 have a minimum distance L therebetween, the winding core 500 is hot pressed between the first pressing plate 302 and the second pressing plate 303.

The method for shaping the winding core 500 by using the winding core shaping system of the embodiment can comprise the following steps:

stretching, namely stretching the winding core 500 which is separated from the winding needle by a stretching device 100 along a radial direction for a set stroke to form the winding core 500 with a set width along the stretching direction and a set thickness vertical to the stretching direction; the stretching and drawing mechanism 101 drives the two support members 102 to extend into the inner ring of the winding core 500, and drives at least one support member 102 to move along the radial direction of the winding core 500 for a set stroke so as to increase the distance between the two support members 102 and stretch the winding core 500 along the radial direction;

rolling, namely placing the stretched roll core 500 on a rolling platform 201, enabling the width direction of the roll core 500 to be parallel to the rolling platform 201, and adjusting the roller rod 202 to move through a rolling traction mechanism to realize rolling of the stretched roll core 500, wherein the support member 102 and the roll core 500 can be placed on the rolling platform 201 together, the roll core 500 is respectively rolled from the middle part to the side part 501 of the width direction of the roll core 500 through the two roller rods 202 under the condition that the support member 102 is located in the roll core 500 and moves away to the maximum distance, when the roller rod 202 is rolled to a set position, the two support members 102 can be drawn out first, and the roller rod 202 continues to roll to the edge of the width direction of the roll core 500 to the surface separated from the roll core; preferably, the winding core 500 has a width L ₁ The roller bar 202 is moved in the width direction to a distance L from the edge of the winding core 500 ₂ And satisfies the following conditions: l is more than or equal to 0.1 ₂ /L ₁ When the thickness is less than or equal to 0.3, the two supporting pieces 102 are pulled out, the roller rod 202 continues to roll towards the edge of the width direction of the winding core 500, and wrinkles caused by the fact that the supporting pieces 101 and the roller rod 202 jointly extrude the inner layer of the winding core 500 are avoided; more preferably, before the two supports 102 are extracted, the two supports 102 move towards each other by a set distance L ₃ Preferably, L ₃ Satisfies the following conditions: l is more than or equal to 0.05 ₃ /L ₁ Less than or equal to 0.3, so as to avoid wrinkles caused by the movement of the inner layer of the winding core 500 when the supporting member 102 is pulled out.

And (3) hot-pressing, wherein the heating mechanism 301 heats the first pressing plate 302 and/or the second pressing plate 303, the rolled core 500 is transferred to the first pressing plate 302 of the hot-pressing device 300, and the second pressing plate 303 moves to a first position towards the first pressing plate 302 along the thickness direction of the rolled core 500 so as to hot-press the rolled core 500 between the first pressing plate 302 and the second pressing plate 303, thereby realizing hot-pressing and shaping of the rolled core 500.

In specific implementation, after the supporting member 102 is separated from the winding core 500, the stretched winding core 500 may be fed into the rolling platform 201 of the rolling device 200 for rolling. For example, referring to fig. 1, the reforming system of some embodiments may include a conveyor belt 400, and the stretching device 100, the rolling device 200, and the hot pressing device 300 are disposed along the conveyor belt 400, and the conveyor belt 400 is used to sequentially convey the core 500 to the stretching device 100, the rolling device 200, and the hot pressing device 300. The rolling platform 201 and the first pressing plate 302 are located below the conveyer belt 400, the roller rod 202 is located above the conveyer belt 400 corresponding to the rolling platform 201, the second pressing plate 303 is located above the conveyer belt 400 corresponding to the first pressing plate 302, and the conveyer belt 400 can transfer the winding core 500 to the rolling platform 201 or the hot pressing platform and stay above the hot pressing platform for a set time length for rolling or hot pressing.

In some embodiments, the hot pressing apparatus 300 further includes a limiting mechanism 307, the limiting mechanism 307 may be connected to the pressing plate driving mechanism 306, and the limiting mechanism 307 is used for limiting the stroke of the pressing plate driving mechanism 306 for driving the second pressing plate 303 to move, thereby controlling the minimum distance between the first pressing plate 302 and the second pressing plate 303 required for hot pressing, so as to effectively prevent the core 500 from being damaged by overpressure when determining the pressure applied to the core 500. In other embodiments, the limiting mechanism 307 may also be disposed between the first pressing plate 302 and the second pressing plate 303, connected to the first pressing plate 302 or the second pressing plate 303, and may abut against between the first pressing plate 302 and the second pressing plate 303 when the first pressing plate 302 and the second pressing plate 303 move to the minimum distance from each other, so as to achieve mechanical limiting, and also effectively prevent the winding core 500 from being over-pressurized.

Because the particularity of rolling up core 500 structure, there are two turnings at the edge of rolling up core 500 width direction, roll up easy fold deformation of core 500 before the design pole piece/barrier film and pole piece free state shift, especially take place easily in naked electric core turning near (between roll up core 500 big plane and turning circular arc transition region, there is the difference in height in this region, pole piece atress is uneven) and the first pole piece of rolling over of inner circle, therefore in the later stage electric core use, the corner is usually inefficacy at first, the black spot appears, it is unusual to analyse lithium etc. to influence the life of electric core. In some embodiments, a pair of sizing dies 304 are attached to the sides of the first and

second platens

302, 303 facing each other, and the two pairs of sizing dies 304 are aligned with each other. The height of the shaping mold 304 on the first pressing plate 302 protruding out of the first pressing plate 302 is H1, the height of the shaping mold 304 on the second pressing plate 303 protruding out of the second pressing plate 303 is H2, wherein H1+ H2 is not more than L, so that interference to the movement of the second pressing plate 303 before the second pressing plate 303 of the shaping mold 304 moves to the first position can be avoided, the core 500 is fully heated, and meanwhile, all parts are uniformly stressed. Two pairs of design moulds 304 are arranged in the hot pressing in-process to support respectively and hold the side corner of the width direction who rolls up core 500, consequently roll up core 500's corner also can the atress when the hot pressing, realize comprehensive hot pressing design effect, reduce the probability that above-mentioned problem appears earlier in later stage electric core use in the corner to effectively promote electric core quality.

After core 500 is tensile and the roll-in, generally form curved surface at width direction's border corner, for optimizing the hot pressing effect of this corner, in some embodiments, be provided with on the design mould 304 and decide profile 305, design profile 305 is the arcwall face, and the design profile 305 in a pair of design mould 304 is towards each other and can surround into semicircular arc surface 105, agree with the corner appearance that core 500 roll-in back formed, thereby this corner can thermally equivalent and atress in hot pressing process, core 500 design effect is rolled up in the improvement.

The roll up core shaping system of this application embodiment realizes rolling up core 500 through draw gear, roll-in device 200 and hot press unit 300 and stretches plastic, roll-in plastic and hot pressing design in proper order, solves electric core pole piece barrier film fold, rolls up core 500 deformation and pole piece aversion problem to can improve electric core interface performance and security performance, promote electric core quality.

The embodiments of the present application have been described in detail with reference to the drawings, but the present application is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present application. Furthermore, the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

Claims

1. Roll up core plastic system, its characterized in that includes stretching device (100), roll-in device (200) and hot press unit (300), wherein:

the stretching device (100) is arranged at an upstream station of the rolling device (200) or is arranged at the same station with the rolling device (200), and the stretching device (100) is used for stretching the cylindrical winding core (500) along the radial direction of the cylindrical winding core (500);

the rolling device (200) comprises a rolling platform (201), a roller rod (202) and a rolling traction mechanism, wherein the rolling platform (201) is provided with a first plane, the first plane is used for bearing the winding core (500) stretched by the stretching device (100), and the rolling traction mechanism is connected to the roller rod (202) and drives the roller rod (202) to move along a direction parallel to the first plane so as to roll the stretched winding core (500);

the hot-pressing device (300) is arranged at a downstream station of the rolling device and is used for receiving the rolled core (500) rolled by the rolling device (200) and carrying out hot pressing.

2. Core shaping system according to claim 1, wherein the stretching device (100) comprises a stretching traction mechanism (101) and two support members (102), the stretching traction mechanism (101) being connected to at least one of the support members (102) and being able to move the two support members (102) away from or towards each other in the rolling direction of the roll bar (202).

3. The core shaping system according to claim 2, wherein the stretching device (100) further comprises a mounting platform (103) and a limiting member (104), and two stretching pulling mechanisms (101), the stretching pulling mechanisms (101) are movably connected to the mounting platform (103), each stretching pulling mechanism (101) is respectively connected to the supporting member (102), and the limiting member (104) is connected to the mounting platform (103) and located on the side of the stretching pulling mechanisms (101) facing away from each other for abutting against the stretching pulling mechanisms (101).

4. Core reshaping system according to claim 2, characterized in that the support members (102) are of elongate rod-like construction and that the sides of the two support members (102) facing away from each other are provided with circular arc surfaces (105).

5. Core shaping system according to claim 2, characterized in that an air flow channel is arranged inside the support member (102), and that the support member (102) is provided with a plurality of air outlets (106) on the sides facing away from each other, and that the air outlets (106) are connected to the air flow channel in the radial direction of the air flow channel, and the air flow channel is adapted to be connected to an air source.

6. The core shaping system according to claim 1, wherein the rolling device (200) comprises two roller bars (202) and two rolling traction mechanisms, each roller bar (202) being connected to one of the rolling traction mechanisms, respectively, the rolling traction mechanisms being capable of adjusting a stroke of the roller bars (202), the stroke comprising a first stroke in which the roller bars (202) are moved in a direction parallel to the rolling platform (201) and a second stroke in which the roller bars (202) are moved in a direction perpendicular to the rolling platform (201).

7. The core reshaping system of claim 1, wherein the hot pressing device (300) comprises a heating mechanism (301), a first pressing plate (302), a second pressing plate (303), and a pressing plate driving mechanism (306), wherein the heating mechanism (301) is configured to heat at least one of the first pressing plate (302) and the second pressing plate (303), the first pressing plate (302) and the second pressing plate (303) are disposed opposite to each other, the first pressing plate (302) is configured to carry the core (500), and the pressing plate driving mechanism (306) is configured to connect and drive the second pressing plate (303) to move between a first position and a second position for pressing the core (500), and when the second pressing plate (303) is in the first position, the first pressing plate (302) and the second pressing plate (303) have a minimum distance L therebetween.

8. The core reshaping system of claim 7, wherein the hot pressing device (300) further comprises a limiting mechanism (307), the limiting mechanism (307) is connected to the platen driving mechanism (306), and the limiting mechanism (307) is configured to limit a stroke of the platen driving mechanism (306) for driving the second platen (303) to move.

9. The core shaping system according to claim 7, wherein a pair of shaping molds (304) are respectively connected to the mutually facing sides of the first pressing plate (302) and the second pressing plate (303), two pairs of shaping molds (304) are aligned with each other, the height of the shaping molds (304) on the first pressing plate (302) protruding out of the first pressing plate (302) is H1, the height of the shaping molds (304) on the second pressing plate (303) protruding out of the second pressing plate (303) is H2, and H1+ H2 is less than or equal to L.

10. The core reshaping system according to claim 9, wherein the sizing die (304) is provided with a sizing surface (305), the sizing surface (305) is an arc surface, and the sizing surfaces (305) of the pair of sizing dies (304) face each other and can enclose a semicircular arc surface.

11. A core shaping method is characterized by comprising the following steps:

rolling: rolling the roll core along the width direction of the stretched roll core; hot pressing: and carrying out hot-press shaping on the rolled core.