All-solid-state battery electrode plate stack surface pressure compression apparatus and all-solid-state battery electrode plate stack press equipment provided therewith

Abstract

This all-solid-state battery electrode plate stack surface pressure compression apparatus of the present invention as described above has good productivity by enabling the compressing of a continuously supplied electrode plate stack to progress at a rapid speed, and has good compression efficiency by applying heat to a compressed portion at the same time as the compressing.

Description

Surface pressure compression device for electrode laminates for all-solid-state batteries and press equipment for electrode laminates for all-solid-state batteries equipped with the same

[0001] The present invention relates to a surface pressure compression device for compressing a laminate of electrode plates for an all-solid-state battery while simultaneously conveying it, and to a press equipment for a laminate of electrode plates for an all-solid-state battery equipped with the same. More specifically, the invention relates to a surface pressure compression device for a laminate of electrode plates for an all-solid-state battery that enables rapid compression by allowing the compression of the laminate of electrode plates to be performed continuously.

[0002] Various types of rechargeable batteries are used in a wide range of applications, from mobile phones, camcorders, and laptop computers to electric vehicles and energy storage systems (ESS). Rechargeable batteries have the advantages of being rechargeable, having a low self-discharge rate, and being free from the memory effect. However, because they use liquid electrolytes, there is a risk of fire or explosion due to thermal runaway during charging and discharging.

[0003] To address these issues, research is being conducted on all-solid-state batteries that utilize solid electrolytes instead of liquid electrolytes. An all-solid-state battery is a battery that uses a solid electrolyte. Solid electrolytes have a higher energy density than liquid electrolytes, relatively shorter charging times, and are safer due to a lower risk of explosion or fire. The solid electrolyte is positioned between the positive and negative electrodes, providing a pathway for lithium ions to pass through. The electrical performance of an all-solid-state battery improves as the contact area between the positive and negative electrodes and the solid electrolyte increases.

[0004] This is because increasing the contact area between the anode, cathode, and solid electrolyte shortens the ion transport path and reduces interfacial resistance, thereby improving battery efficiency. Lower interfacial resistance facilitates the movement of lithium ions, increasing electrochemical reaction efficiency and potentially enhancing the battery's output and energy density.

[0005] For this reason, the production process of all-solid-state batteries includes a step of compressing the electrode stack (a stack of a positive electrode, solid electrolyte, and negative electrode). The reason for compressing the electrode stack is to eliminate voids within the stack, thereby increasing the contact area between the positive and negative electrodes and the electrolyte and improving battery performance.

[0006] Conventional surface compression devices for compressing electrode plate laminates include a pair of pressure rollers. The electrode plate laminate is compressed as it passes between the pressure rollers. However, this type of pressure roller compression device has the disadvantage of not having high compression efficiency for electrode plate laminates. This is because the electrode plate laminate is compressed only by line contact as it passes between the pressure rollers during transport.

[0007] Pre-compression applies excessively high local pressure to the compression area, which can cause excessive deformation or material damage to the electrode plate laminate. In addition, because it is difficult to apply uniform pressure across the entire electrode plate laminate, there is a possibility that internal voids may not be completely removed. There is a need for a surface pressure compression device capable of producing an electrode plate laminate with good performance by applying uniform pressure to the entire surface of the electrode plate laminate to efficiently remove internal voids. In this regard, Korean Registered Patent Publication No. 10-2549831 (Method for manufacturing an all-solid-state battery) has been disclosed.

[0008] The present invention was created to resolve the above-mentioned problems and aims to provide a surface pressure compression device for an all-solid-state battery electrode plate laminate that has good productivity and good compression efficiency by applying heat to the compression portion simultaneously with compression.

[0009] The surface pressure compression device for a laminated electrode plate for an all-solid-state battery according to the present invention, as a means of solving the problem to achieve the above objective, receives an electrode plate for an all-solid-state battery continuously transmitted from the outside and moves it along an internal transport path while compressing it, and comprises: a support structure that provides support force; a plurality of guide rolls that are rotatably provided on the support structure and provide said transport path; a drive roll that is rotatably installed on the support structure; a roll drive unit that rotates the drive roll; a pressing unit that is positioned corresponding to the drive roll and applies a compression force toward the drive roll; and a circulation belt that contacts the drive roll and the guide roll, receives the rotational force of the drive roll when the drive roll rotates, and moves in a circulating motion along said transport path, passing between the pressing unit and the drive roll while overlapping with the electrode plate transmitted from the outside.

[0010] In addition, the drive roll is equipped with a heater that heats the electrode plate laminate that is compressed while passing through the drive roll and the pressing unit.

[0011] In addition, multiple pressing units are installed along the circumferential direction of the drive roll.

[0012] In addition, the pressing unit comprises a plurality of pressure rollers that press the electrode plate body toward the driving roller, a roller housing that rotatably supports the pressure rollers, and a spacing adjustment unit that adjusts the spacing of the pressure rollers relative to the driving rollers.

[0013] In addition, an additional compression unit is provided to further compress the electrode plate laminate separated from the circulation belt after passing between the drive roll and the pressing unit.

[0014] In addition, it further has a temperature control module that heats the circulation belt to transfer heat to the electrode plate body in contact with the circulation belt.

[0015] In addition, it includes a tension control unit that controls the tension of the circulation belt by applying pressure to the circulation belt.

[0016] In addition, a meandering control sensor is further provided to detect meandering of the circulation belt during circulation of the above-mentioned circulation belt.

[0017] Meanwhile, in another aspect of the present invention, a press machine for an all-solid-state battery is provided, comprising: an electrode plate laminate surface pressure pressing device; and an additional pressing unit that passes the electrode plate laminate separated from the circulation belt after passing between the drive roll and the pressing unit and performs additional pressing.

[0018] In this case, the additional compression unit is equipped with rollers facing each other, so that the electrode plate laminate that has passed through the surface pressure compression device can be pressed by linear pressure as it passes between the rollers.

[0019] The surface pressure compression device for an all-solid-state battery electrode laminate according to the present invention, as described above, can perform compression on a continuously supplied electrode laminate at a high speed, thereby providing good productivity, and also has good compression efficiency by applying heat to the compression portion simultaneously with compression.

[0020] In addition, since the electrode plate laminate can be uniformly compressed through surface pressure and then linear pressure applied to achieve the desired thickness, compression with uniform density occurs, and defects such as bubble formation do not occur.

[0021] FIG. 1 is a drawing showing the overall configuration of a surface pressure compression device for an all-solid-state battery according to one embodiment of the present invention.

[0022] Figures 2 and 3 are drawings to explain the circulation structure and role of the circulation belt in the surface pressure compression device of Figure 1.

[0023] FIG. 4 is a diagram showing the transport path of a laminated electrode in a surface pressure compression device according to one embodiment of the present invention.

[0024] FIGS. 5 and FIGS. 6 are drawings for explaining the operation method of the pressing unit illustrated in FIGS. 1.

[0025] Figure 7 is an enlarged view of part A of Figure 1, and Figure 8 is an enlarged view of part B of Figure 1.

[0026] Hereinafter, one embodiment according to the present invention will be described in more detail with reference to the attached drawings.

[0027] FIG. 1 is a drawing showing the overall configuration of a press equipment for a solid-state battery electrode plate laminate according to an embodiment of the present invention, and FIG. 2 and FIG. 3 are drawings for explaining the circulation structure and role of the circulation belt in the surface pressure compression device of the press equipment for a solid-state battery electrode plate laminate of FIG. 1. In addition, FIG. 4 is a drawing showing the conveying path of the electrode plate laminate in the surface pressure compression device, and FIG. 5 and FIG. 6 are drawings for explaining the operation method of the pressing unit shown in FIG. 1.

[0028] The press equipment for a solid-state battery electrode plate laminate according to the present embodiment is equipment that compresses the electrode plate laminate (101) for a solid-state battery while moving it along a transport path. The reason for compressing the electrode plate laminate (101) is that if the electrode plate laminate (101) forming layers is compressed in the thickness direction, the structure becomes dense and internal voids are eliminated, thereby expanding the contact area of ​​the solid electrolyte with respect to the positive and negative electrodes.

[0029] The electrode plate stacking press equipment for an all-solid-state battery according to the present embodiment is equipped with a surface pressure pressing device (20) and an additional pressing part (60).

[0030] The surface pressure compression device (20) of the present embodiment can transfer the electrode plate body (100) delivered from the electrode plate laminate supply unit (10) to the additional compression unit (60) after surface pressure. The 'surface pressure' is a compression in which a pressure member (in this embodiment, a drive roller and a circulation belt) in contact with the upper and lower surfaces of the object, i.e., the electrode plate laminate, is pressed toward the electrode plate laminate.

[0031] In the same concept, the electrode plate body (101) that is compressed while passing between the rollers is compressed in a state of line contact with the rollers, so it can be called line pressing. The electrode plate laminate (101) compressed by the surface pressure compression device (20) can be moved to an additional compression section (60) and further compressed. That is, the electrode plate laminate (101) that has passed through the surface pressure compression device (20) is pressed by line pressure while passing between the rollers.

[0032] Additionally, the electrode plate laminate (101) can be moved in a state laminated on a base film (103), as shown in FIG. 1. The base film (103) is peeled off and removed after the compression of the electrode plate laminate (101) is completed. However, according to the embodiment, only the electrode plate laminate (101) may be transported without applying the base film (103).

[0033] In this embodiment, a supply unit (10) may be located on the upstream side of the continuous surface pressure compression device (20), and an additional compression unit (60) may be located on the downstream side. The supply unit (10) serves to continuously deliver the electrode plate laminate (101) to be compressed to the surface pressure compression device (20).

[0034] The additional compression unit (60) further compresses the electrode plate body (101) that has passed through the surface compression compression device (20). That is, the electrode plate stack (101), which has been separated from the circulation belt (23) after passing between the drive roll and the pressing unit, is passed through and further compressed. The electrode plate stack (101) passes between the rollers (61) of the additional compression unit (60), is compressed, and then transferred to a subsequent process.

[0035] The surface pressure compression device (20) according to the present embodiment includes a support structure (21), a plurality of guide rolls (21a), a driving roll (31), a roll driving unit, a pressing unit (40), a circulation belt (23), a temperature control module (25), a tension control unit (35), a meandering control sensor (47), and a temperature sensor (27).

[0036] The support structure (21) serves to support the components constituting the surface pressure compression device (20). That is, it fixes and supports various elements including the guide roll (21a), the drive roll (31), the roll drive unit, and the pressing unit (40) to ensure that each element operates smoothly. As long as it can perform this role, the configuration of the support structure (21) can be implemented in various forms.

[0037] Additionally, the guide roll (21a) is rotatably mounted on the support structure (21) and, together with the drive roll (31), provides a conveying path for the circulation belt (23). As shown in FIG. 2, the circulation belt (23) continuously circulates along the guide roll (21a) and the drive roll (31). During the circulation movement of the circulation belt (23), the guide roll (21a) rotates due to friction with the circulation belt (23).

[0038] The drive roll (31) is rotatably installed on the support structure (21) and rotates by a motor (33). The motor (33) is a roll drive unit that operates by a control signal transmitted from a control unit (not shown) to rotate the drive roll (31). The rotational speed of the drive roll (31) is adjustable. The circulation belt (23) receives the rotational force of the drive roll (31) and performs a circulating motion.

[0039] In particular, a heater (31a) is installed inside the drive roll (31). The heater (31a) heats the electrode plate laminate (101) that is compressed while passing between the drive roll (31) and the pressing unit (40). When heat is applied to the electrode plate laminate (101) while it is being compressed, the compression efficiency can be increased. The operation of the heater (31a) is also controlled by a control unit not shown. Ultimately, the drive roll (31) serves the dual function of moving the circulation belt (23) and releasing heat. The pressing unit (40) is positioned correspondingly on the outer circumference of the drive roll (31) and provides a pressing force toward the drive roll. Multiple pressing units (40) are installed along the circumferential direction of the drive roll (31). In this embodiment, two sets of pressing units (40) are applied.

[0040] The pressing unit (40) includes a roll housing (41), a pressure roll (43), and a gap adjustment part (45).

[0041] The roll housing (41) rotatably supports the pressure roll (43). The roll housing (41) is slidably supported on the support structure (21) and can move back and forth relative to the drive roll (31). The support structure (21) is equipped with a supporter (not shown) that supports the roll housing (41).

[0042] The pressure roller (43) is rotatably mounted on the inside of the roll housing (41). In this embodiment, two pressure rollers (43) are applied inside the roll housing (41). However, the number of pressure rollers (43) applied may vary depending on the embodiment. The pressure roller (43) comes into contact with the circulation belt (23) and presses the circulation belt (23) toward the drive roller (31). The electrode plate laminate (101) that is overlapping the circulation belt (23) is compressed in the thickness direction between the pressure roller (43) and the drive roller (31). Since a total of four pressure rollers (43) are applied, compression can be performed four times.

[0043] The spacing between each pressure roll (43) and the driving roll (31) is set differently. The spacing of the pressure roll (43) relative to the outer surface of the driving roll (31) is such that the spacing of the pressure roll (43) at the beginning, entering in the direction of arrow e in FIG. 1 (Fig. 8), is relatively wide, and gradually narrows as it goes downstream.

[0044] The above gap adjustment unit (45) serves to adjust the gap of the pressure roll (43) relative to the drive roll (31). The gap adjustment unit (45) is an actuator that moves the roll housing (41) while fixed to the support structure (21). FIG. 6 shows the roll housing (41) retracted in the direction of arrow k. FIG. 5 also shows the roll housing (41) moved toward the drive roll (31) in the direction of arrow m. As the roll housing (41) moves closer to the drive roll (31), the pressure applied to the electrode plate laminate (101) increases.

[0045] The circulation belt (23) is supported on the outer surface of the guide roll (21a) and the drive roll (31) and moves in a circulating motion by receiving the driving force of the drive roll (31). The circulation belt (23) can be made of stainless steel. The circulation belt (23) has a certain width and thickness. The thickness of the circulation belt (23) can be varied, for example, it can have a thickness of 0.3 m to 0.5 mm. The diameter of the guide roll (21a) supporting the circulation belt (23) is at least 160 times the thickness of the circulation belt (23). The circulation belt (23) always maintains a taut state. The tension of the circulation belt (23) is achieved by the tension control unit (35) described later.

[0046] As described above, the circulation belt (23) is in contact with the drive roll (31) and the guide roll (21a), and when the drive roll rotates, it receives the rotational force of the drive roll and moves in a circulating motion along the conveying path.

[0047] In particular, the circulation belt (23) serves as a carrier for transporting the electrode plate body (101). That is, as shown in FIGS. 1 and 7, the electrode plate stack (101) entering from the supply unit (10) in the direction of arrow a joins the circulation belt (23), moves in an overlapping state with the circulation belt (23), and passes between the pressure roll (43) and the drive roll (31) of the pressing unit and is compressed. In addition, the electrode plate stack (101) that has passed through the pressure roll (43) and the drive roll (31) is separated from the circulation belt (23) and moves toward the additional compression unit (60) along the direction of arrow g. The electrode plate stack (101) passes through the surface pressure compression device (20) along the path shown in FIG. 4.

[0048] The temperature control module (25) heats the circulation belt (23) so that heat is transferred to the electrode plate body (101) in contact with the circulation belt. The electrode plate laminate (101) is indirectly heated by the temperature control module (25). The output temperature of the temperature control module (25) is adjustable.

[0049] The temperature control module (25) heats the circulation belt (23). Since the electrode plate body (101) overlaps the circulation belt (23), the heat output from the temperature control module (25) is transferred to the electrode plate body (101). Consequently, the temperature control module (25) heats the electrode plate laminate (101) through the circulation belt (23) to increase the compression efficiency. The temperature control module (25) can heat the circulation belt (23) to a temperature of 150°C to 170°C.

[0050] In addition, the temperature sensor (27) detects the temperature of the circulation belt (23) in real time and transmits the detected data to the temperature control module (25). The temperature control module (25) maintains the temperature of the circulation belt (23) within the above temperature range based on the temperature information received from the temperature sensor (27).

[0051] The tension control unit (35) elastically presses a portion of the circulation belt (23) in the direction of arrow p of FIG. 3 to control the tension of the circulation belt (23). That is, it keeps the circulation belt (23) taut. The tension control unit (35) maintains the tension of the circulation belt (23) constant by reflecting the amount of expansion and contraction when the circulation belt expands or contracts due to heat provided by the temperature control module (25). The circulation belt (23) can be kept taut by the tension control unit (27).

[0052] The tension control unit (35) includes an actuator (35a) and a connecting body (35b). The actuator (35a) is operated by a separate control unit and adjusts the position of the connecting body (35b). The connecting body (35b) is an assembly that rotatably supports some guide rolls (21a) and presses the circulation belt (23) in the direction of arrow p in Fig. 3 by the actuator (35a). Of course, the stronger the force applied in the direction of arrow p, the stronger the tension of the circulation belt (23).

[0053] Additionally, the meandering control sensor (47) detects meandering during the circulation movement of the circulation belt (23). The detection results of the meandering control sensor (47) are transmitted to a separate control unit. When meandering occurs, the control unit returns the circulation belt (23) that has meandered to its normal position.

[0054] It is important that the circulation belt formed from the above stainless steel material circulates flat without wrinkles and comes into surface contact with the electrode plate laminate. To this end, the operation of the temperature control module (25) and the tension control unit (35) is important.

[0055] The electrode plate laminate surface pressure compression device (20) for an all-solid-state battery according to the present embodiment, as described above, compresses the electrode plate laminate (101) while conveying it, thereby making the structure of the electrode plate laminate dense and expanding the contact area between the positive and negative electrodes and the solid electrolyte. In particular, during the compression process by the driving roll (31) and the pressing unit (40), the compression efficiency is good due to the heat generated by the driving roll (31) and the heat transferred through the temperature control module (25).

[0056] The circulation belt (23) circulates along the conveying path and passes the electrode plate stack between the drive roll (31) and the guide roll (21a), thereby enabling continuous pressing while in contact with the electrode plate. This continuous structure maximizes efficiency in the mass production process and enables the production of electrode plate stacks of uniform quality. In addition, through the temperature control module (25) and the temperature sensor (27), quality degradation caused by temperature changes during the pressing process can be prevented. The electrode plate stack, which is uniformly pressed throughout after passing through the above-mentioned surface pressure pressing device for all-solid-state batteries, passes through the additional pressing section (60) and is pressed by line contact to be compressed to an appropriate thickness and density.

[0057] 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.

[0058] The surface pressure compression device for all-solid-state batteries according to the present invention applies heat to the part where the electrode plate laminate is compressed while being transported, thereby improving compression efficiency and enabling the production of high-quality products, making it industrially applicable.

Claims

1. A compression device that receives an electrode plate for an all-solid-state battery continuously delivered from the outside, moves it along an internal transport path, and compresses it, A supporting structure that provides support; A plurality of guide rolls rotatably provided on a support structure and providing the above transfer path; A drive roller rotatably installed on a support structure; A roll drive unit that rotates a drive roll; and A pressing unit positioned corresponding to the above-mentioned drive roll and applying a pressing force toward the drive roll; A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized by including a circulation belt that contacts the drive roll and guide roll, receives the rotational force of the drive roll when the drive roll rotates, and moves in a circulating motion along the conveying path while passing between the pressing unit and the drive roll in a state overlapping with an electrode plate body transmitted from the outside.

2. In Paragraph 1, In the above drive roller, A surface pressure compression device for an all-solid-state battery electrode laminate, characterized by including a heater that heats the electrode laminate being compressed while passing through a drive roll and a pressing unit.

3. In Paragraph 1, The above pressing unit, A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized by having multiple units installed along the circumferential direction of the drive roller.

4. In Paragraph 3, The above pressing unit is, A plurality of pressure rollers that press the electrode plate body toward the driving roller side, and A roll housing that rotatably supports a pressure roll, and A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized by including a gap adjustment unit that adjusts the gap of a pressure roll relative to a driving roll.

5. In Paragraph 1, A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized by further including a temperature control module that heats the above-mentioned circulation belt to transfer heat to the electrode plate body in contact with the circulation belt.

6. In Paragraph 1, A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized by including a tension control unit that controls the tension of the circulation belt by applying pressure to the circulation belt.

7. In Paragraph 1, A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized by further including a meandering control sensor that detects meandering of the circulation belt during circulation of the above-mentioned circulation belt.

8. In Paragraph 1, A surface pressure compression device for an all-solid-state battery electrode plate laminate, characterized in that the above-mentioned circulation belt is made of stainless steel and has a thickness of 0.3 m to 0.5 mm.

9. A surface pressure compression device for a laminated electrode according to any one of claims 1 to 8; and A press equipment for a solid-state battery electrode plate laminate, characterized by including an additional compression unit that passes the electrode plate laminate separated from the circulation belt after passing between the above-mentioned drive roll and pressing unit and performs additional compression.

10. In Paragraph 9, The above additional compression unit is equipped with rollers facing each other, A press equipment for a solid-state battery electrode laminate, characterized in that the electrode laminate passing through the above surface pressure compression device is pressed by linear pressure while passing between the above rollers.

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