Electrode dry coating apparatus

Abstract

The present invention relates to an electrode dry coating apparatus. This electrode dry coating apparatus comprises: a current collector supply unit which continuously supplies current collector foil by unwinding the current collector foil from a wound state; a coating unit which forms an electrode film which is to be coated on the current collector foil, while simultaneously passing the current collector foil therethrough and coating one surface of the current collector foil with the electrode film, wherein the coating unit comprises: a plurality of rolling rolls, some of which are arranged horizontally and the remainder of which are vertically arranged to have a ㄱ-shaped arrangement structure as a whole; and a first coating roll and a second coating roll which are installed under the lowermost rolling roll, and through which the electrode film formed by the rolling rolls and the current collector foil are passed and laminated; and a winding unit which winds a laminate that has passed through the coating unit. In the electrode dry coating apparatus of the present invention constructed as described above, a dry electrode film having uniform density and thickness may be continuously formed through multi-stage rolls arranged in horizontal and vertical directions and simultaneously may be laminated on current collector foil, thereby enabling the manufacture of a dry electrode having precise specifications.

Description

Electrode dry coating device

[0001] The present invention relates to an electrode coating device for a secondary battery, and more specifically, to an electrode dry coating device capable of continuously forming a dry electrode film of uniform density and thickness through multi-stage rolls arranged in horizontal and vertical directions and simultaneously laminating the dry electrode film to a current collector foil.

[0002] Unlike disposable primary batteries, lithium secondary batteries are rechargeable and reusable. They boast high output and excellent charge-discharge performance. Consequently, they are widely used in a variety of fields, from mobile IT devices like smartphones and laptops to power sources for electric vehicles and storage devices for power generated by wind and solar power.

[0003] Secondary batteries are composed of a positive electrode, a negative electrode, an electrolyte, and a separator. The positive and negative electrodes are manufactured into a secondary battery cell through an electrode process, which involves dispersing or dissolving active materials, conductive materials, and binders in a solvent to create a slurry, coating the slurry onto a current collector, and then drying it. The process then includes an assembly process and an activation process.

[0004] However, wet electrode manufacturing methods using solvents can sometimes produce defects such as pinholes and cracks during the drying process. Pinholes and cracks occur as the contained solvent evaporates. Furthermore, differences in solvent evaporation rates can cause powder floating, which degrades electrode quality.

[0005] To address the aforementioned issues, a dry manufacturing method for manufacturing electrodes without using solvents is known. This dry manufacturing method involves passing electrode powder containing an active material, a binder, and a conductive material through a calender roll. The electrode powder, having passed through the calender roll, is laminated and fixed to a current collector as a dry electrode film of a certain thickness.

[0006] In this regard, Korean Patent Publication No. 10-2022-0052852 (Electrode powder for manufacturing dry electrode for secondary battery, manufacturing method thereof, manufacturing method of dry electrode using same, dry electrode, secondary battery including same, energy storage device, and dry electrode manufacturing device) has been disclosed.

[0007] The disclosed dry electrode manufacturing device is a dry electrode manufacturing device, and comprises: a blender for mixing raw materials for a mixture including an active material, a conductive material, and a binder; a kneader for kneading the mixture to form a mixture lump to fiberize the binder; a crusher for crushing the mixture lump to form an electrode powder; a calender for forming the electrode powder into a mixture film; and a lamination roll for positioning and laminating the mixture film on at least one surface of a current collector.

[0008] However, the above-mentioned conventional dry electrode manufacturing device, although it is described that the powder is processed into a film form by calendering, does not disclose a specific configuration for forming it into a film form.

[0009] The purpose of the present invention is to provide an electrode dry coating device capable of continuously forming a dry electrode film of uniform density and thickness through multi-stage rolls arranged in horizontal and vertical directions and simultaneously laminating the same to a current collector foil.

[0010] As a technical solution for achieving the above object, the electrode dry coating device of the present invention includes: a current collector supply unit that continuously supplies a current collector foil in a wound state by unwinding it; a coating unit that forms an electrode film to be coated on the current collector foil and coats the electrode film on one surface of the current collector foil by passing the current collector foil through the current collector foil, some of which are arranged horizontally and the rest are arranged vertically, and has an overall L-shaped arrangement structure; a first coating roll and a second coating roll that are installed under the lowermost rolling roll and pass the electrode film formed by the rolling roll through the current collector foil and laminate them; and a winding unit that winds up a laminate that has passed through the coating unit.

[0011] In addition, the coating section is further provided with a pair of fixed support plates that are perpendicular to the ground and keep the rolling roll and the first and second coating rolls in parallel, and a plurality of roll driving sections that individually rotate the rolling roll and the first and second coating rolls.

[0012] In addition, the fixed support plate takes the form of a plate having a certain thickness, and each fixed support plate is provided with an L-shaped mounting space having a horizontal extension space extending horizontally as a passage penetrating in the thickness direction of the fixed support plate, and a vertical extension space extending vertically and connected to an end of the horizontal extension space, and a roll support block supporting both ends of the rolling roll and the first and second coating rolls is accommodated in the mounting space.

[0013] In addition, the rotation speed of the plurality of rolling rolls gradually increases from the uppermost rolling roll to the lowermost rolling roll, and the rotation speed of the first and second coating rolls is faster than the rotation speed of the lowermost rolling roll.

[0014] Additionally, the speeds of the first coating roll and the second coating roll are the same.

[0015] And, among the above rolling rolls, there are three or more rolling rolls arranged horizontally.

[0016] In addition, a gap adjustment unit is further included to adjust the gap between the adjacent rolling rolls, the gap between the first and second coating rolls, and the gap between the first coating roll and the rolling roll by adjusting the gap between the roll support blocks.

[0017] In addition, among the neighboring roll support blocks, a pressure slope is formed on one or both sides of the roll support blocks, and the gap adjustment unit includes a taper block that is interposed between the neighboring roll support blocks and contacts the roll support blocks, and a block driving unit that moves the taper block linearly so that the taper block presses the pressure slope to widen the gap between the roll support blocks.

[0018] In addition, the taper block has a female screw hole formed therein, and the block driving unit has a screw rod that is supported axially on a fixed support plate and is coupled to the female screw portion of the taper block, and a rod rotating unit that axially rotates the screw rod.

[0019] Additionally, a spacing indicator is installed between adjacent roll support blocks to indicate the spacing between the roll support blocks.

[0020] In addition, a heating means for heating the above rolling roll and the first and second coating rolls is further provided.

[0021] In addition, among the above rolling rolls, a powder hopper is installed on the upper portion of the first rolling roll and the second rolling roll on the upstream side to receive and supply electrode powder provided from the outside.

[0022] In addition, the current collector supply unit comprises: a support structure that provides support; a horizontal shaft that supports a current collector foil that is horizontally supported and wound on the support structure; and an unwinder that rotates the horizontal shaft, and the unwinder determines the rotation speed of the horizontal shaft based on the magnitude of the tension of the current collector foil transmitted to the horizontal shaft.

[0023] In addition, the winding unit includes a winding shaft that is horizontally supported on a fixed support plate and winds the laminate, and a winder that rotates the winding shaft, and the winder determines the rotation speed of the winding shaft according to the size of the tension of the laminate transmitted to the winding shaft.

[0024] The electrode dry coating device of the present invention, which is constructed as described above, can continuously form a dry electrode film of uniform density and thickness through multi-stage rolls arranged in horizontal and vertical directions and simultaneously laminate it to a current collector foil, thereby enabling the manufacture of a dry electrode having a precise specification.

[0025] Figures 1 and 2 are perspective views of an electrode dry coating device according to one embodiment of the present invention.

[0026] Figure 3 is a partially exploded perspective view of the dry coating device of Figure 1.

[0027] FIG. 4 is a drawing for explaining a gap adjustment method of each roll in a dry coating device according to one embodiment of the present invention.

[0028] Fig. 5 is an enlarged drawing showing the mounting structure of the dial gauge of Fig. 1.

[0029] FIG. 6 is a drawing for explaining the heating method of each roll in an electrode dry coating device according to one embodiment of the present invention.

[0030] FIG. 7 is a drawing for explaining the operation of a dry coating device according to one embodiment of the present invention.

[0031] Hereinafter, one embodiment according to the present invention will be described in more detail with reference to the attached drawings.

[0032] FIG. 1 and FIG. 2 are perspective views of an electrode dry coating device according to an embodiment of the present invention, and FIG. 3 is a partially exploded perspective view of the dry coating device of FIG. 1. In addition, FIG. 4 is a drawing for explaining a gap adjustment method of each roll in a dry coating device according to an embodiment of the present invention, and FIG. 5 is an enlarged drawing showing the mounting structure of the dial gauge of FIG. 1. In addition, FIG. 6 is a drawing for explaining a heating method of each roll in an electrode dry coating device according to an embodiment of the present invention.

[0033] As shown, the electrode dry coating device (10) according to the present embodiment includes a current collector supply unit (37), a coating unit (12), and a winding unit (40).

[0034] The current collector supply unit (37) continuously supplies the current collector foil (36) by unwinding it from a wound state. The current collector foil (36) is an aluminum foil having a certain width and is wound in a roll shape as shown in Fig. 3.

[0035] And the coating unit (12) forms an electrode film and simultaneously coats the formed electrode film on one side of the current collector foil. The coating unit (12) forms an electrode film to be coated on the current collector foil (36) and simultaneously passes the current collector foil through it and laminates the electrode film on one side of the current collector foil.

[0036] And the winding unit (40) winds the electrode laminate (39 in Fig. 7) that has passed through the coating unit (12). The electrode laminate (39) is a result of a dry electrode film being laminated on one side of a current collector foil (36).

[0037] The above coating unit (12) includes a base (11), a fixed support plate (13), a rolling roll, a roll support block (17), a gap adjustment unit (21), first and second coating rolls (15e, 15f), and a roll driving unit (33).

[0038] The base (11) is a horizontal plate fixed to the ground and supports the current collector supply unit (37) and the coating unit (12).

[0039] The fixed support plate (13) is a steel plate of a certain thickness that is vertically erected and fixed at the lower end to the base (11). The thickness of the fixed support plate (13) is 70 mm or more. The fixed support plates (13) are paired in pairs, and a rolling roll is accommodated between them. The specifications and shapes of the fixed support plates (13) on both sides are identical.

[0040] In addition, each fixed support plate (13) is provided with a mounting space (13f). The mounting space (13f) is an 'ㄱ'-shaped passage (hole) that penetrates the thickness direction of the fixed support plate (13). As illustrated in Fig. 3, the mounting space (13f) has a horizontal extension space (13a) that extends horizontally and a vertical extension space (13b) that is connected to an end of the horizontal extension space (13a) and extends vertically. The horizontal extension space (13a) and the vertical extension space (13b) each have a constant width and are bent at a right angle.

[0041] In addition, a plurality of vertical passages (13d) are provided on the upper portion of the horizontal extension space (13a). The vertical passages (13d) are holes into which screw rods (21b) are installed. The screw rods (21b) are capable of axial rotation while being accommodated in the vertical passages (13d).

[0042] Likewise, a number of horizontal passages (13c) are formed on the side of the vertical extension space (13b). The horizontal passages (13c) are also holes through which the screw rod (21b) passes. The screw rod (21b) can rotate about its axis while being accommodated in the horizontal passages (13c).

[0043] A plurality of roll support blocks (17) are installed within the mounting space (13f) of the fixed support plates (13) on both sides. The roll support blocks (17) have the same shape and are symmetrical with the rolling roll or coating roll interposed therebetween. The roll support blocks (17) are placed on the inward surfaces of the horizontal extension space (13a) and the vertical extension space (13b).

[0044] A roll support block (17) is built into the above-mentioned L-shaped mounting space, and the rolling roll and the first and second coating rolls are supported by the L-shaped support block. Consequently, the rolling roll and the first and second coating rolls have an overall L-shaped arrangement structure. That is, some rolling rolls are arranged horizontally, and the remaining rolling rolls and the first and second coating rolls are arranged vertically. Although the first and second coating rolls are named 'coating rolls' due to their function, their shape is identical to that of the rolling roll.

[0045] In this embodiment, there are three rolling rolls arranged horizontally. Furthermore, by arranging the rolls (rolling rolls, first and second coating rolls) in an L-shape as described above, it is easy to supply electrode powder from the hopper, and the overall size of the equipment is reduced, allowing for a compact configuration. Furthermore, since the rolls are arranged vertically, maintainability is excellent.

[0046] In this embodiment, a total of six roll support blocks (17) are applied. Among the plurality of roll support blocks (17), the roll support block (17) located at the corner where the horizontal extension space (13a) and the vertical extension space (13b) meet is fixed and does not move, and serves as a reference point for the remaining roll support blocks (17). The internal angle of the lower left vertex of the roll support block (17) fixed to the corner forms a right angle. In the following description, the roll support block fixed to the corner will be referred to as a 'fixed roll support block' for convenience.

[0047] The remaining two roll support blocks (17) accommodated in the horizontal extension space (13a) can be positionally adjusted in the horizontal direction. That is, the spacing between the two roll support blocks (17) or the spacing with respect to the fixed roll support block (17) can be adjusted. In addition, the spacing between the three roll support blocks (17) installed in the vertical extension space (13b) can be adjusted vertically below the fixed roll support block (17).

[0048] A separation prevention plate (18) is fixed to the edges on both sides of the above roll support block (17). The separation prevention plate (18) prevents the roll support block (17) from falling out of the fixed support plate (13).

[0049] In addition, as illustrated in Fig. 4, an end block (23) is fixed to the left end of the horizontal extension space (13a) and the lower end of the vertical extension space (13b), respectively. The end block (23) is a block-shaped member that interfaces with the taper block (19). A pressure inclined surface (23a) that is in contact with the taper block (19) described later is formed on the end block (23) provided in the horizontal extension space (13a).

[0050] In particular, among the neighboring roll support blocks, a pressure inclined surface (17b) is formed on one or both roll support blocks. The pressure inclined surface (17b) is an inclined portion inclined at a certain angle with respect to a vertical or horizontal plane.

[0051] Specifically, the right side of the two roll support blocks (17) accommodated in the horizontal extension space (13a) is not vertical but is inclined to form a pressure slope (17b). In contrast, the left side is vertical.

[0052] In addition, the bottom surfaces of the three roll support blocks (17) accommodated in the vertical extension space (13b) are all inclined to form a pressure inclined surface (17b). In the case of the uppermost roll support block (17) among the three roll support blocks (17), the pressure inclined surface (17b) is formed on both the bottom surface and the upper surface.

[0053] The above gap adjustment unit (21) is a component that adjusts the gap of the roll support block (17). The reason for adjusting the gap of the roll support block is to adjust the gap between adjacent rolling rolls, the gap between the first and second coating rolls, and the gap between the first coating roll and the rolling roll. By adjusting the gap between the rolling rolls and the gap between the rolling roll and the first coating roll, the thickness of the electrode film can be adjusted. In addition, by adjusting the gap between the first and second coating rolls, the pressing force of the electrode film against the current collector foil (36) can be controlled.

[0054] The gap adjustment unit (21) includes a taper block (19) and a block driving unit. The taper block (19) is a block-shaped member that is interposed between adjacent roll support blocks (17) and between the end block (23) and the roll support block (17) and that contacts the roll support block (17). One side of the taper block (19) is in contact with the pressure inclined surface (17b).

[0055] Since the pressure slope (17b) is inclined, when the taper block (19) is pulled in the direction of arrow a in Fig. 4, the pressure slope (17b) is pressed by the taper block and spreads in the direction of arrow b. This means that the gap between the adjacent roll support blocks (17) is widened.

[0056] The block drive unit causes the taper block (19) to move linearly, so that the taper block presses the pressure slope and widens the gap between the roll support blocks.

[0057] The above taper block (19) has a female screw hole (19a) formed therein. The female screw hole (19a) is a hole with a female screw thread formed on the inner surface, and is screw-connected with a screw rod (21b).

[0058] The block driving part includes a screw rod (21b) and a handle (21a) as a rod rotating part. The screw rod (21b) is a rod-shaped member having a male thread formed on a portion of the outer surface, and is screw-connected to the female thread hole (19a) of the taper block while being supported by the horizontal passage (13c) and the vertical passage (13d), respectively. It goes without saying that the taper block (19) moves linearly according to the axial rotation of the screw rod (21b).

[0059] The above handle (21a) functions as a rod rotation unit that rotates the screw rod (21b) about its axis. The handle (21a) is manually operated by the operator. In some cases, the gap adjustment unit (21) may be configured as an electric unit. For example, an electric unit can be implemented by applying a servo motor in place of the handle (21a).

[0060] Ultimately, the gap between the roll support blocks (17) is adjusted by rotating the handle (21a). The change in the gap between the roll support blocks (17) can be determined through the gap indicator. The gap indicator is installed between adjacent roll support blocks and indicates the gap between the roll support blocks. In the present embodiment, the gap indicator is a dial gauge (27 in Fig. 5).

[0061] In order to mount the above dial gauge (27), a first measuring block (28) is mounted on one side of the roll support block (17) (among the neighboring roll support blocks), and a second measuring block (29) is mounted on the other side of the roll support block (17).

[0062] The main body (27a) of the dial gauge (27) is fixed to the first measuring block (28), and the sensor button (27d) is in contact with the second measuring block (29). When the gap of the roll support block (17) changes, the sensor button (27d) moves back and forth and indicates the gap after the change. The worker adjusts the gap of the roll support block while looking at the dial gauge (27).

[0063] Meanwhile, the above-mentioned rolling roll is a roll installed horizontally in parallel between fixed support plates (13). Both ends of the rolling roll are supported axially on roll support blocks (17). Of course, the gap of the rolling roll is adjusted by adjusting the spacing of the roll support blocks (17).

[0064] The above rolling rolls include a first rolling roll (15a), a second rolling roll (15b), a third rolling roll (15c), and a fourth rolling roll (15d).

[0065] The first, second, and third rolling rolls (15a, 15b, and 15c) are arranged horizontally within a horizontal extension space (13a) and are parallel to each other. The gap between the second rolling roll (15b) and the third rolling roll (15c) is narrower than the gap between the first rolling roll (15a) and the second rolling roll (15b). In this embodiment, there are three rolling rolls arranged horizontally. The number of rolling rolls arranged horizontally may vary depending on the embodiment.

[0066] In addition, the fourth rolling roll (15d) is arranged vertically below the third rolling roll (15c) and in parallel. The gap between the fourth rolling roll (15d) and the third rolling roll (15c) is narrower than the gap between the second rolling roll (15b) and the third rolling roll (15c). The fourth rolling roll is arranged vertically below the third rolling roll. The number of rolling rolls arranged vertically may also vary.

[0067] The first coating roll (15e) and the second coating roll (15f) are installed under the lowest rolling roll, i.e., the fourth rolling roll (15d). The first coating roll (15e) is positioned under the fourth rolling roll (15d), and the second coating roll (15f) is arranged parallel to the lower portion of the first coating roll (15e). The third rolling roll (15c) to the second coating roll (15f) are arranged vertically and parallel to each other.

[0068] The gap between the first coating roll (15e) and the second coating roll (15f) is wider than the gap between the fourth rolling roll (15d) and the first coating roll (15e). The first and second coating rolls (15e, 15f) pass the electrode film (39a) that is finally rolled by passing through the fourth rolling roll (15d) and the first coating roll (15e) and simultaneously pass the current collector foil (36) through and laminate them. Therefore, the gap between the first and second coating rolls (15e, 15f) is wider than the gap between the fourth rolling roll and the first coating roll by the thickness of the current collector foil (36).

[0069] The first and second coating rolls (15e, 15f) pass between the first, second, third and fourth rolling rolls and between the fourth rolling roll and the first coating roll, and simultaneously pass the film-formed electrode film (39a) and the current collector foil (36) through them to combine them, and then transfer them to the winding unit (40).

[0070] In addition, the first rolling roll (15a) to the fourth rolling roll (15d) and the first and second coating rolls (15e, 15f) described above are individually rotated by the roll driving unit (33). As shown in Fig. 2, the roll driving unit (33) is located on the outside of the fixed support plate (13) and is independently driven to output rotational force.

[0071] By the above-mentioned roll driving unit (33), the first rolling roll (15a) to the fourth rolling roll (15d) and the first and second coating rolls (15e, 15f) rotate at different rotation speeds.

[0072] That is, the second rolling roll (15b) rotates 50% faster than the rotation speed of the first rolling roll (15a). In addition, the third rolling roll (15c) rotates 50% faster than the second rolling roll (15b), and the fourth rolling roll (15d) rotates 50% faster than the third rolling roll (15c). In addition, the first coating roll (15e) rotates faster than the fourth rolling roll (15d). However, the rotation speed of the second coating roll (15f) is the same as the rotation speed of the first coating roll (15e).

[0073] Ultimately, the rotation speed of the plurality of rolling rolls gradually increases from the uppermost rolling roll to the lowermost rolling roll, the rotation speed of the first and second coating rolls is faster than the rotation speed of the lowermost rolling roll, and the rotation speeds of the first and second coating rolls are the same. The rotation direction of each rolling roll and coating roll is indicated by an arrow in Fig. 7.

[0074] As illustrated in Fig. 7, a powder hopper (51) is installed above the first rolling roll (15a) and the second rolling roll (15b). The powder hopper (51) receives electrode material powder provided from the outside and supplies it between the first and second rolling rolls (15a, 15b).

[0075] In addition, the first rolling roll (15a) to the fourth rolling roll (15d) and the first and second coating rolls (15e, 15f) are equipped with heating means. The heating means heats the first to fourth rolling rolls and the first and second coating rolls (15e, 15f) to a temperature of 200°C or lower. The rolling rolls and the coating rolls are heated within a temperature range from room temperature to 200°C.

[0076] In this embodiment, a heater rod (31) is applied as the heating means described above. The heater rod (31) is a heating member built into each of the rolling rolls (15a, 15b, 15c, 15d) and the first and second coating rolls (15e, 15f), and generates heat by power provided from the outside to heat the rolling rolls and coating rolls.

[0077] Meanwhile, the current collector supply unit (37) continuously supplies the current collector foil (36) by unwinding it. The current collector foil (36) supplied from the current collector supply unit (37) passes between the first coating roll (15e) and the second coating roll (15f), meets and combines with the electrode film, and is then wound in the winding unit (40).

[0078] The current supply unit (37) includes a support structure (37a), a horizontal shaft (38e), and an unwinder (38).

[0079] The support structure (37a) is an element fixed to the upper part of the base (11) and is spaced apart from the coating portion (12). The horizontal shaft (38e) supports the current collector foil (36) that is supported and wound around the support structure (37a) so as to be axially rotatable.

[0080] The unwinder (38) rotates the horizontal shaft (38e) to allow the current collector foil (36) to be released. The unwinder (38) includes a torque output unit (38a), a driven pulley (38c), and a belt (38b).

[0081] The torque output unit (38a) is mounted on the support structure (37a) and outputs rotational force. In addition, the driven pulley (38c) is a member fixed to the end of the horizontal shaft (38e) (the end of the horizontal shaft (38e) is connected to the driven pulley (38c) while passing through the support structure (37a).) and is connected to the torque output unit (38a) via a belt (38b). For this purpose, the torque output unit (38a) is provided with a drive pulley (not shown) on which the belt (38b) is filled. When the torque output unit (38a) is driven to rotate the horizontal shaft (38e), the current collector foil (36) is unwound at a constant speed.

[0082] In particular, the control of the rotation speed of the horizontal shaft (38e) is determined based on the tension of the collector foil (36) transmitted to the horizontal shaft (38e). For example, when the tension of the collector foil (36) during transport becomes greater than the set tension, the rotation speed of the horizontal shaft increases. Conversely, when the tension of the collector foil becomes less than the set tension, the rotation speed of the horizontal shaft decreases.

[0083] The winding unit (40) winds the electrode laminate (39) that has passed through the coating unit (12). The winding unit (40) includes a winding shaft (43e) and a winder (41).

[0084] The winding shaft (43e) is a shaft that is supported so as to be axially rotatably on a fixed support plate (13) on one side. The winding shaft (43e) is maintained horizontally and is axially rotated by the winder (41). The winding shaft (43e) winds the electrode laminate (39) through axial rotation.

[0085] The winder (41) includes a torque output unit (41a), a belt (41b), and a driven pulley (41c). The torque output unit (41a) outputs rotational force while being fixed to the outer side of the fixed support plate (13). In addition, the driven pulley (38c) is fixed to the end of the winding shaft (43e) and is connected to the torque output unit (41a) via a belt (41b). Of course, the torque output unit (41a) is provided with a drive pulley (not shown) on which the belt (41b) is filled. When the torque output unit (41a) is driven to rotate the winding shaft (43e), the electrode laminate (39) is wound.

[0086] Also, similar to the unwinder (38), the rotation speed of the take-up shaft (43e) is determined by the tension of the electrode laminate (39) transmitted to the take-up shaft (43e). That is, when the tension of the electrode laminate (39) during transport becomes greater than the set tension, the rotation speed of the take-up shaft (43e) increases, and when the tension becomes less than the set tension, the rotation speed of the take-up shaft (43e) decreases.

[0087] Figure 7 is a drawing for explaining the operation of a dry coating device (10) according to one embodiment of the present invention.

[0088] The coating device (10) of this embodiment has a structure that continuously supplies electrode powder and current collector foil (36) to produce an electrode laminate (39).

[0089] The roll driving unit (33) is operated while the above powder hopper (51) is filled with electrode powder (53). As the roll driving unit (33) is operated, the electrode powder (53) passes through the first rolling roll (15a) and the second rolling roll (15b), the second rolling roll (15b) and the third rolling roll (15c), the third rolling roll (15c) and the fourth rolling roll (15d), and the fourth rolling roll (15d) and the first coating roll (15e), and is formed into an electrode film (39a), and then passes between the first coating roll (15e) and the second coating roll (15f).

[0090] At this time, the current collector foil (36) supplied from the current collector supply unit (37) also passes through the first coating roll (15e) and the second coating roll (15f) and meets and is combined with the electrode film (39a). That is, the electrode film (39a) is tightly fixed to one side of the current collector foil (36).

[0091] In addition, the electrode laminate (39) that has passed through the coating section (12) is wound on the winding section (40) to complete the electrode dry coating process.

[0092] Above, the present invention has been described in detail through specific examples, but the present invention is not limited to the above examples, and various modifications are possible by a person of ordinary skill within the scope of the technical idea of ​​the present invention.

[0093] It is industrially applicable because it is possible to continuously form a dry electrode film of uniform density and thickness through multi-stage rolls arranged in horizontal and vertical directions and simultaneously laminate it to a current collector foil.

Claims

1. A current collector supply unit that continuously supplies current collector foil by unwinding the current collector foil in a wound state; A coating unit having a plurality of rolling rolls having an L-shaped arrangement structure overall, some of which are arranged horizontally and others are arranged vertically, and a first coating roll and a second coating roll that are arranged vertically below the lowest rolling roll and that pass and combine the electrode film formed by the rolling roll and the current collector foil; wherein the electrode film to be coated on a current collector foil is formed while simultaneously passing the current collector foil through the rolling roll and coating the electrode film on one side of the current collector foil; A winding unit for winding the laminate that has passed through the above coating unit is included. Electrode dry coating device.

2. In paragraph 1, In the above coating part, A pair of fixed support plates that are perpendicular to the ground and keep the rolling roll and the 1st and 2nd coating rolls parallel, It further includes a plurality of roll driving units that individually rotate the above rolling roll and the first and second coating rolls. Electrode dry coating device.

3. In paragraph 2, The above fixed support plate takes the form of a plate having a certain thickness, Each fixed support plate is provided with an L-shaped mounting space having a horizontal extension space extending horizontally as a passage extending in the thickness direction of the fixed support plate, and a vertical extension space extending vertically and connected to the end of the horizontal extension space. In the mounting space, a roll support block that supports both ends of the rolling roll and the first and second coating rolls is accommodated. Electrode dry coating device.

4. In paragraph 2, The rotation speed of the above plurality of rolling rolls is The rotation speed gradually increases from the uppermost rolling roll to the lowermost rolling roll, and the rotation speed of the first and second coating rolls is faster than the rotation speed of the lowermost rolling roll. Electrode dry coating device.

5. In paragraph 4, The speeds of the first coating roll and the second coating roll are the same. Electrode dry coating device.

6. In paragraph 2, Among the above rolling rolls, there are three or more rolling rolls arranged horizontally. Electrode dry coating device.

7. In paragraph 3, A gap adjustment unit is further included to adjust the gap between adjacent rolling rolls, the gap between the first and second coating rolls, and the gap between the first coating roll and the rolling roll by adjusting the gap between the above roll support blocks. Electrode dry coating device.

8. In paragraph 7, Among the neighboring roll support blocks, a pressure slope is formed on one or both sides of the roll support blocks, The above gap adjustment unit, A tapered block that is interposed between adjacent roll support blocks and is interviewed by the roll support blocks, Equipped with a block driving unit that moves the taper block in a straight line, presses the taper block against the pressure slope, and widens the gap between the roll support blocks. Electrode dry coating device.

9. In paragraph 8, The above taper block has a female screw hole formed, The above block driving part is, A screw rod that is supported rotatably on a fixed support plate and is connected to the female screw portion of the taper block, Having a rod rotation part that rotates the screw rod, Electrode dry coating device.

10. In paragraph 7, Between the neighboring roll support blocks, Equipped with a spacing indicator that indicates the spacing of the roll support blocks, Electrode dry coating device.

11. In paragraph 2, A heating means for heating the above rolling roll and the first and second coating rolls is further provided. Electrode dry coating device.

12. In paragraph 2, Among the above rolling rolls, a powder hopper is installed on the upper part of the first rolling roll and the second rolling roll on the upstream side to receive and supply electrode powder provided from the outside. Electrode dry coating device.

13. In paragraph 2, The above-mentioned power supply unit; It comprises a support structure that provides support, a horizontal shaft that supports a current collector foil that is horizontally supported and wound on the support structure, and an unwinder that rotates the horizontal shaft. The unwinder is; The rotation speed of the horizontal shaft is determined based on the tension of the collector foil transmitted to the horizontal shaft. Electrode dry coating device.

14. In paragraph 13, The above winding part; It includes a winding shaft that is supported horizontally on a fixed support plate and winds the laminate, and a winder that rotates the winding shaft. The winder; The rotation speed of the winding shaft is determined according to the size of the tension of the laminate transmitted to the winding shaft. Electrode dry coating device.

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