Vibration-suppressive coating device for dry electrode material

Abstract

The vibration-suppressive coating device for dry electrode material of the present invention, which is configured as described above, is hardly affected by vibration generated by a motor during operation, thus having excellent operational precision. Accordingly, a dry electrode sheet having uniform density and uniform thickness can be continuously produced.

Description

Vibration-suppressing dry electrode material coating device

[0001] The present invention relates to an electrode material coating device for a secondary battery that coats electrode materials on both sides of a current collector transported along a transport path, and more specifically, to a vibration-suppressing dry electrode material coating device that has excellent coating precision as it is hardly affected by motor vibration during operation.

[0002] Unlike primary batteries, which are used once and then discarded, secondary batteries are rechargeable batteries that can be reused repeatedly and possess high output and excellent charge / discharge performance. Accordingly, secondary batteries are used importantly in various fields, ranging from mobile IT devices such as smartphones and laptop computers to power sources for electric vehicles and storage devices for storing electricity generated from wind or solar power generation.

[0003] A secondary battery has a basic composition of a positive electrode, a negative electrode, an electrolyte, and a separator. The positive electrode and the negative electrode are each manufactured into a secondary battery cell through an electrode process in which an active material, a conductive material, and a binder are dispersed or dissolved in a solvent to prepare a slurry, and the slurry is coated onto a current collector and then dried, followed by an assembly process and an activation process.

[0004] However, wet electrode manufacturing methods using solvents may result in defects such as pinholes or cracks during the drying process. Pinholes or cracks occur as the contained solvent evaporates. In addition, powder flotation occurs due to differences in the solvent evaporation rate, and powder flotation is a cause of degraded electrode quality.

[0005] To solve the aforementioned problems, a dry manufacturing method for producing electrodes without using a solvent is known. The dry manufacturing method is performed by passing an electrode material powder containing an active material, a binder, and a conductive material through a plurality of calender rolls. The electrode material powder that has passed through the calender rolls is laminated and fixed to a current collector as a dry electrode film having a certain thickness.

[0006] Regarding dry coating devices, Korean published patent application No. 10-2023-0142043 (Dry coating device for electrode active material) has been disclosed. The disclosed coating device is a dry coating device for dry coating a secondary battery active material onto a current collector, comprising: a first roller and a second roller installed adjacently spaced apart by a predetermined distance and fiberizing an active material supplied while rotating in different directions; a third roller and a fourth roller positioned parallel to the first roller and the second roller and installed adjacently spaced apart by a predetermined distance, fiberizing an active material supplied while rotating in different directions; and elastic bodies installed between the first roller and the second roller, between the second roller and the third roller, and between the third roller and the fourth roller, wherein the first roller and the second roller have a configuration in which they are connected by blocks. However, the conventional coating device has the disadvantage that, during operation, vibrations generated from the motor are transmitted to the rollers.

[0007] The present invention aims to provide a vibration-suppressing dry electrode coating device that has excellent operational precision as it is hardly affected by vibrations generated by a motor during operation.

[0008] The vibration-suppressing dry electrode material coating device of the present invention, as a means of solving the problem for achieving the above objective, comprises: a support structure providing support; a housing installed on the support structure that passes a current collector to be coated through; a rolling unit having a plurality of rolling rolls that are mutually paralleled within the housing, roll electrode material powder introduced from the outside to coat the current collector, and whose spacing can be adjusted; a rolling roll drive unit that rotates the rolling rolls so that the electrode material powder passes through the rolling rolls in sequence and is coated on the current collector; and a spacing support structure that supports the rolling roll drive unit and is installed separately from the support structure to suppress vibrations generated from the rolling roll drive unit from being transmitted to the rolling unit.

[0009] In addition, the above-mentioned rolling roll drive unit includes a motor corresponding one-to-one to the rolling roll, and each motor is connected to the rolling roll through a coupling.

[0010] In addition, the above-mentioned spaced support structure is provided with a linear guide that is straightly extended in the longitudinal direction and a carrier plate that is slidably supported on the linear guide and supports a motor.

[0011] In addition, the above-mentioned spacing support structure further includes a synchronization means for moving the carrier plate simultaneously with the rolling roll when adjusting the spacing of the rolling roll.

[0012] In addition, the above synchronization means comprises: a sensor unit that detects the movement of a rolling roll; a synchronization signal output unit that receives the detection information from the sensor unit and generates a movement signal of a carrier plate; and a plate transfer unit that moves the carrier plate by means of the synchronization signal output unit.

[0013] In addition, the plate transfer unit includes a rack gear fixed to a carrier plate, a synchronous motor installed on a spaced support structure and controlled by a synchronous signal output unit, and a drive gear that meshes with the rack gear and rotates by the synchronous motor.

[0014] In addition, the motor is a water-cooled motor, and a cooling water supply unit that circulates cooling water to the motor is further provided.

[0015] The vibration-suppressing dry electrode material coating device of the present invention, as described above, is hardly affected by vibrations generated by the motor during operation, so it has excellent operational precision and can continuously produce dry electrode sheets with uniform density and thickness.

[0016] FIG. 1 is a front view of a vibration-suppressing dry electrode material coating device according to one embodiment of the present invention.

[0017] FIG. 2 is a perspective view of the electrode material coating device illustrated in FIG. 1.

[0018] Figure 3 is a front view showing the rolling unit of Figure 1 separately.

[0019] FIG. 4 is a side view illustrating the principle of vibration suppression in the coating device illustrated in FIG. 1.

[0020] Figure 5 is a plan view of Figure 4.

[0021] FIG. 6 is a drawing illustrating a modified example of a coating device according to one embodiment of the present invention.

[0022] FIG. 7 is a diagram illustrating the simultaneous movement method of the carrier plate illustrated in FIG. 6.

[0023] Hereinafter, one embodiment according to the present invention will be described in more detail with reference to the attached drawings.

[0024] FIG. 1 is a front view of a vibration-suppressing dry electrode material coating device (10) according to one embodiment of the present invention, and FIG. 2 is a perspective view of the electrode material coating device shown in FIG. 1. In addition, FIG. 3 is a front view showing the rolling unit of FIG. 1 separately, and FIG. 4 is a side view to explain the principle of vibration suppression in the coating device shown in FIG. 1. FIG. 5 is a plan view of FIG. 4.

[0025] As described above, the vibration-suppressing dry electrode coating device (10) according to the present embodiment includes a support structure (13), a rolling unit (20), a rolling roll drive unit, and a spaced support structure (15).

[0026] The electrode material coating device (10) is a device that passes a current collector (101) continuously supplied from the outside and continuously coats electrode material (103) on both sides of the current collector (101). The current collector (101) receives electrode material (103) on both sides while passing through the rolling unit (20). The result of coating electrode material (103) on both sides of the current collector (101) is an electrode sheet (100). The electrode material (103) is produced by rolling electrode material powder supplied through a hopper (31) using a plurality of rolling rolls. In particular, in the coating device (10) of this embodiment, vibrations generated from the motor (33) during operation are hardly transmitted to the rolling unit (20), so there is no decrease in precision due to vibration. The support structure (13) serves to support the rolling unit (20) while fixed on the ground. A plurality of guide rolls (11) may be installed in the support structure (13). The electrode sheet (100) is moved to an external winding section while supported by a guide roll (11).

[0027] The rolling unit (20) is installed on the upper part of the support structure (13). The rolling unit (20) includes a housing (21), a plurality of rolling rolls (27), a fixing plate (25), a roll support block (22), a block pusher (23), and a plurality of control valves (24).

[0028] A rolling unit (20) is separately illustrated in FIG. 3. The housing (21) allows the current collector (101) to be coated to pass through from the bottom and is fixed horizontally to the upper part of the support structure (13). As shown in FIG. 4, the housing (21) is open vertically. The current collector (101) passes downward through the interior of the housing (21). While the current collector (101) passes through the housing (21), electrode material (103) is coated on both sides of the current collector (101).

[0029] Additionally, a guide rail (21a) is mounted on the housing (21). Two guide rails (21a) are mutually parallel and extend horizontally. The guide rail (21a) supports the roll support block (22) so that it can slide. The roll support block (22) can slide while supported by the guide rail (21a). As will be described later, as the roll support block (22) moves up and down, the gap of the rolling roll (27) can be adjusted. Also, when the gap of the rolling roll (27) is adjusted, the thickness of the electrode material (103) can be adjusted.

[0030] The roll support block (22) is a block-shaped member that is positionally adjustable and supported on the guide rail (21a). Two roll support blocks (22) form a pair and have a rolling roll (27) between them. Both ends of the rolling roll (27) are supported by the roll support block (22) and are rotatable. Adjacent rolling rolls (27) rotate in opposite directions.

[0031] Rolling rolls (27) are received in a housing (21) in parallel with each other and roll electrode powder fed from a hopper (31), and coat the surface of a current collector (101) passing between some of the rolling rolls. Rolling rolls (27) are received in a housing (21) in parallel with each other and, as mentioned, both ends are supported by roll support blocks (22). The rolling rolls are arranged in parallel in the transverse direction and are spaced apart at intervals corresponding to the thickness of the electrode material to be produced. The spacing of the rolling rolls is adjusted by adjusting the spacing of the roll support blocks (22).

[0032] Additionally, the fixed plate (25), as shown in FIG. 3, is a plate-shaped member fixed vertically to the housing (21) and fixes some rolling rolls (27) in place. That is, it prevents the rolling rolls from moving along the guide rail (21a). The rolling rolls (27) fixed to the fixed plate (25) are only capable of rotational movement in place.

[0033] However, other rolling rolls other than the rolling roll (27) tied to the fixed plate (25) can be positioned along the longitudinal direction of the guide rail (21a). Therefore, based on the fixed rolling roll (27), if the left rolling roll in the drawing of FIG. 3 moves to the right, the gap between the rolling rolls (27) narrows, allowing a thinner electrode material (103) to be formed. Similarly, if the right rolling roll in the drawing of FIG. 3 moves to the left, the gap between the rolling rolls narrows, allowing the electrode material (103) to be formed thinner.

[0034] The rolling roll (27) fixed to the fixed plate (25) is a rolling roll located in the center among a plurality of rolling rolls. When there is an even number of rolling rolls, one of the two rolling rolls located at the very center is fixed to the fixed plate (25).

[0035] Each rolling roll can rotate by receiving rotational force from the rolling roll drive unit. The rolling roll drive unit will be described later.

[0036] The hopper (31) is located above two rolling rolls (27) located at the left and right ends of a plurality of rolling rolls and supplies electrode material powder. The electrode material powder passes between the two rolling rolls located at the ends, is rolled once, and then starts toward the current collector (101).

[0037] The circumferential speeds of the aforementioned rolling rolls are all different. The circumferential speed of the rolling rolls located at the left and right ends is the slowest, and the circumferential speed of the two rolling rolls passing through the current collector (101) is the fastest. The circumferential speed of the rolling rolls gradually increases from the end rolling rolls (27) to the central rolling rolls.

[0038] As the circumferential speed of the rolling rolls gradually increases toward the center as described above, the electrode material powder fed into the hopper (31) can pass between each rolling roll (27) and move to the current collector (101) to be coated. It is a known fact that the current collector passing through two rollers rotating at different speeds is conveyed by adhering to the outer surface of the relatively faster roller.

[0039] The block pusher (23) is a hydraulic actuator mounted between each roll support block (22) and adjusts the spacing between adjacent roll support blocks (22). Adjusting the spacing of the block support blocks (22) means adjusting the spacing of the rolling rolls. The reason for adjusting the spacing of the rolling rolls is to adjust the thickness of the electrode material (103). The block pusher (23) is operated by a pusher drive unit. The pusher drive unit includes a hydraulic supply unit (37) and a plurality of control valves (24) as shown in FIG. 1. The hydraulic supply unit (37) is a unit including a hydraulic pump and a hydraulic fluid tank, is connected to the control valve (24), and transmits hydraulic pressure to the control valve (24).

[0040] The control valve (24) is a proportional control valve and is connected to each block pusher (23) and transmits hydraulic pressure to the block pusher (23). The block pusher (23) operates by the transmitted hydraulic pressure to adjust the spacing of adjacent roll support blocks (22). Each block pusher (23) can be controlled independently through the control valve (24).

[0041] Meanwhile, the rolling roll drive unit rotates each rolling roll (27) so that the electrode material powder passes through the rolling rolls (27) in sequence and is coated on the current collector (101). That is, each rolling roll (27) is rotated at a different speed so that the powder passes through the rolling rolls in sequence and reaches the current collector (101).

[0042] The rolling roll drive unit includes a motor (33). The motor (33) corresponds one-to-one with the rolling roll (27) and is connected to the rolling roll (27) through a coupling (35). The rotational force of the motor (33) can be transmitted to the rolling roll (27) through the coupling (35).

[0043] In particular, the rolling roll drive unit is supported by a spaced support structure (15) as shown in FIG. 4. The spaced support structure (15) supports the rolling roll drive unit, but is installed separately from the support structure (13) to suppress vibrations generated in the rolling roll drive unit from being transmitted to the rolling unit.

[0044] Since the spacing support structure (15) is spaced apart from the support structure (13) and the rolling unit (20), vibrations generated in the rolling roll drive unit, that is, vibrations generated from the motor (33), are hardly transmitted to the rolling unit (20). Almost all vibrations are transmitted to the ground through the spacing support structure (15). A linear guide (15a) and a carrier plate (34) are further installed on the upper part of the spacing support structure (15). The linear guide (15a) is a straight member that is horizontally extended parallel to the guide rail (21a) and supports the carrier plate (34).

[0045] The carrier plate (34) is a plate-shaped member that supports the motor (33) and has a slider (34a) on its bottom surface. The slider (34a) is supported so as to be slidable on the linear guide (15a).

[0046] The motor (33) can move along the longitudinal direction of the linear guide (15a) while supported by the carrier plate (34). That is, when the rolling roll (27) is moved by the block pusher (23), the motor (33) can be pulled along by the rolling roll (27). Since the rolling roll (27) and the motor (33) are connected by a coupling (35), the motor (33) can move along the rolling roll (27).

[0047] The above motor (33) is a water-cooled motor. As illustrated in enlarged view in FIG. 2, the motor (33) is provided with an inlet (33a) and an outlet (33b).

[0048] The inlet port (33a) is a port that receives cooling water delivered from the cooling water supply unit (39) through the cooling water circulation pipe (51). Additionally, the outlet port (33b) is a hole through which cooling water that has completed heat exchange with the motor is discharged. The discharged cooling water is returned to the cooling water supply unit (39) through the cooling water circulation pipe (51), cooled, and then circulated back to the motor (33).

[0049] Additionally, as illustrated in FIG. 4, a roll heating unit (28) is applied to each rolling roll (27). The roll heating unit (28) heats the rolling roll to enable more efficient rolling of the electrode material (103). The roll heating unit (28) includes a heater (28a) and a heater driver (28c). The heater (28a) is a linear heating element installed inside the rolling roll and generates heat by power transmitted through the heater driver (28c). The heating temperature of the heater (28a) can be controlled through the heater driver (28c).

[0050] FIG. 6 is a drawing illustrating a modified example of a coating device (10) according to one embodiment of the present invention, and FIG. 7 is a drawing for explaining the method of simultaneous movement of the carrier plate (34) shown in FIG. 6.

[0051] In this description, the 'simultaneous movement' of the carrier plate (34) refers to the simultaneous movement of the rolling roll (27) and the carrier plate (34). That is, it means that when the rolling roll (27) moves, the carrier plate (34) moves simultaneously through the action of the synchronization means.

[0052] As described above, a synchronization means is installed in the spacing support structure (15). The synchronization means serves to move the carrier plate (34) simultaneously with the rolling roll when adjusting the spacing of the rolling roll (27). By applying the synchronization means, the motor (33) itself receives driving force and can perform translational movement almost simultaneously with the rolling roll (27). That is, the motor (33) does not move by being pulled by the rolling roll (27), but moves on its own by the applied driving force.

[0053] The synchronization means includes a sensor unit (41), a synchronization signal output unit (43), and a plate transfer unit (45). The synchronization means is applied in a one-to-one correspondence to each motor (33).

[0054] The sensor unit (41) is a sensor installed on one side of the carrier plate (34) and detects the movement of the rolling roll (27). For example, when the rolling roll (27) moves to adjust the gap between the rolling rolls, it detects the direction of movement and the distance of movement of the rolling roll (27).

[0055] The information detected by the sensor unit (41) is transmitted to the synchronization signal output unit (43). The synchronization signal output unit (43) receives the detection information from the sensor unit and generates a movement signal for the carrier plate (34). That is, the plate transfer unit (45) is driven based on the received sensing information.

[0056] The plate transfer unit (45) is controlled by the synchronization signal output unit (43) and moves the carrier plate. The plate transfer unit (45) includes a synchronization motor (45a), a drive gear (45b), and a rack gear (45c).

[0057] The synchronous motor (45a) is installed on the upper side of the spaced support structure (15) and outputs driving force based on a signal transmitted from the synchronous signal output unit. The driving force of the synchronous motor (45a) is transmitted to the rack gear (45c) through the driving gear (45b).

[0058] The rack gear (45c) is a gear fixed to the carrier plate (34) and meshes with the drive gear (45b). The drive gear (45b) meshes with the rack gear (45c) and transmits the rotational force of the synchronous motor (45a) to the rack gear (45c) so that the position of the carrier plate (34) is adjusted.

[0059] Although the present invention has been described in detail through specific embodiments, the present invention is not limited to the above embodiments, and various modifications can be made by those skilled in the art within the scope of the technical concept of the present invention.

[0060] The vibration-suppressing dry electrode material coating device of the present invention is virtually unaffected by vibrations generated by a motor, resulting in excellent operational precision. Since it continuously produces electrode sheets with uniform density and thickness, it is suitable for industrial use.

Claims

1. A supporting structure that provides load-bearing capacity; A rolling unit installed on a support structure, comprising a housing through which a current collector to be coated passes, and a plurality of rolling rolls that are mutually parallel and accommodated within the housing, rolling electrode material powder introduced from the outside to coat the current collector, and having adjustable spacing; A rolling roll drive unit that rotates the above rolling rolls so that electrode material powder passes through the rolling rolls in sequence and is coated on the current collector; and A vibration-suppressing dry electrode coating device characterized by including a spaced support structure installed separately from the support structure to support the rolling roll drive unit and suppress vibrations generated in the rolling roll drive unit from being transmitted to the rolling unit.

2. In Paragraph 1, The above rolling roll drive unit is, A vibration-suppressing dry electrode coating device characterized by including a motor corresponding to a rolling roll in a one-to-one manner, wherein each motor is connected to the rolling roll through a coupling.

3. In Paragraph 2, The above-mentioned spaced support structure includes, A linear guide extended in a straight line in the longitudinal direction, and A vibration-suppressing dry electrode coating device characterized by having a carrier plate that is slidably supported on a linear guide and supports a motor.

4. In Paragraph 3, The above-mentioned spaced support structure includes, A vibration-suppressing dry electrode coating device characterized by further including a synchronization means for moving a carrier plate simultaneously with the rolling roll when adjusting the gap of the rolling roll.

5. In Paragraph 4, The above synchronization means is, A sensor unit that detects the movement of rolling rolls, and A synchronization signal output unit that receives detection information from the sensor unit and generates a movement signal for the carrier plate, and A vibration-suppressing dry electrode material coating device characterized by having a plate transfer unit that moves a carrier plate by means of a synchronization signal output unit.

6. In Paragraph 5, The above plate transfer unit is, A rack gear fixed to a carrier plate, and A synchronous motor installed on a spaced support structure and controlled by a synchronous signal output unit, and A vibration-suppressing dry electrode coating device characterized by including a drive gear that meshes with the above rack gear and rotates by a synchronous motor.

7. In Paragraph 2, The above motor is, It is a water-cooled motor, and A vibration-suppressing dry electrode material coating device characterized by further being equipped with a cooling water supply unit that circulates cooling water to the motor.

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