Electrode slurry provider, coating device and die coater

Abstract

The present specification relates to an electrode slurry provider, a coating apparatus and a die coater.

Description

[Technical field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0153054, filed with the Korean Intellectual Property Office on November 9, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present specification relates to an electrode slurry provider, a coating apparatus and a die coater. [Background technology]

[0003] In recent years, the demand for environmentally friendly alternative energy sources has been increasing due to rising energy source prices caused by the depletion of fossil fuels and growing concern over environmental pollution. As a result, research into various power generation technologies such as atomic, solar, wind, and tidal power has been ongoing, and there is also a high interest in power storage devices to use the energy produced in this way more efficiently.

[0004] In particular, the demand for batteries as an energy source is increasing rapidly as technological development and demand for mobile devices increases, and much research is being conducted into batteries that can meet this demand.

[0005] Typically, in terms of battery shape, there is a high demand for thin-walled rectangular secondary batteries and pouch-type secondary batteries that can be applied to products such as mobile phones, etc. In terms of materials, there is a high demand for lithium secondary batteries such as lithium ion batteries and lithium ion polymer batteries that have advantages such as high energy density, discharge voltage, and output stability.

[0006] In general, a secondary battery includes an electrode assembly in which a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode are stacked. The positive electrode and the negative electrode are manufactured by coating an electrode slurry containing an active material on a current collector.

[0007] For coating the electrodes with the electrode slurry, the electrode slurry is provided from a tank storing the electrode slurry in a number of branches into a number of lines, and coating is carried out for each line.

[0008] At this time, research is required to provide a uniform flow rate for each line. Summary of the Invention [Problem to be solved by the invention]

[0009] The present disclosure seeks to provide an electrode slurry provider, a coating apparatus and a die coater. [Means for solving the problem]

[0010] One embodiment of the present specification provides an electrode slurry providing device including: a tank for storing electrode slurry; a main pipe having one end connected to the tank; and two or more branch pipes configured to discharge the electrode slurry flowing in from the main pipe, wherein the point at which the branch pipes are connected to the main pipe becomes gradually lower as the point at which the branch pipes are connected to the main pipe becomes farther from the tank.

[0011] Another embodiment herein includes two or more pumps, each located at a point where the branch pipe and the main pipe are connected.

[0012] Another embodiment of the present specification is a method for manufacturing a water supply system comprising: a water supply system for supplying a water to a tank; and a water supply system for supplying a water supply to the tank. The ratio of the height difference (B) between one end of the main pipe connected to the tank and the point where the branch pipe and the main pipe are connected in the gravity direction is 2:1 to 3:1.

[0013] In another embodiment of the present specification, the main pipe includes a connecting pipe connected to the tank, and a straight pipe coupled to the connecting pipe and connected to the two or more branch pipes.

[0014] In another embodiment of the present specification, the angle between a plane perpendicular to the direction of gravity and the central axis of the straight tube is not less than 5 degrees and not more than 25 degrees.

[0015] Yet another embodiment of the present disclosure provides a coating apparatus or die coater that dispenses the electrode slurry provided from the electrode slurry providing apparatus described above. Effect of the Invention

[0016] The electrode slurry providing device according to the present specification can supply electrode slurry at a uniform flow rate from one electrode slurry tank to a plurality of branch pipes, regardless of the physical properties of the electrode slurry.

[0017] The electrode slurry providing device according to the present specification can increase the number of branch pipes per tank. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a cross-sectional view of a conventional electrode slurry providing device. [Diagram 2] FIG. 2 is a cross-sectional view of an electrode slurry provider according to the present disclosure. [Diagram 3] FIG. 2 is a bottom view of an electrode slurry provider according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, the present invention will be described in detail with reference to the drawings. However, the drawings are for illustrative purposes only and the scope of the present invention is not limited by the drawings.

[0020] 2 is a cross-sectional view of the electrode slurry providing apparatus 1 according to the present specification, and FIG. 3 is a bottom view of the electrode slurry providing apparatus 1 according to the present specification. The electrode slurry providing apparatus 1 includes a tank 10, a main pipe 20, and a branch pipe 30.

[0021] In the electrode slurry coating process, a tank 10 that supplies electrode slurry to a coating device discharges the electrode slurry through one main pipe 20, and the main pipe 20 supplies the electrode slurry discharged from the tank 10 to the coating device (not shown) through a plurality of branch pipes 30 that are individually connected to pumps (not shown). At this time, the type of the coating device is not particularly limited as long as it is a device that can coat the electrode slurry, and may be, for example, a comma coater, a spin coater, a slot die coater, or the like.

[0022] Here, the electrode slurry providing device 1, the tank 10, the main pipe 20 and the branch pipe 30 can each be formed from a metal material having a certain rigidity, and any material may be used as long as it can withstand the pressure caused by the supply of the electrode slurry.

[0023] The tank 10 may be cylindrical in shape as long as it can store the electrode slurry. The bottom surface of the tank 10 has a convex shape so that the electrode slurry stored in the tank can be used efficiently, and the electrode slurry stored in the tank can be discharged to the main pipe 20 from a discharge port provided at the lowest position of the convex shape.

[0024] In the conventional electrode slurry providing device 1 as shown in FIG. 1, the main pipe 20 connected to the tank 10 is disposed horizontally with the ground, and the branch pipes are formed at the same height, resulting in a problem that the flow rate of the electrode slurry discharged through each branch pipe is different. Specifically, the flow rate of the electrode slurry is higher in the branch pipe located closer to the tank, and the flow rate of the electrode slurry is lower in the branch pipe located relatively farther from the tank. In addition, if the viscosity of the electrode slurry is too low or too high, the electrode slurry may not even be discharged to the branch pipe located farther from the tank. This phenomenon becomes more serious as the amount of electrode slurry in the tank is smaller.

[0025] In contrast, in the electrode slurry providing device 1 according to the present specification, as shown in Fig. 2, one end of the main pipe 20 connected to the tank 10 is obliquely disposed higher than the other end. The flow rate of the electrode slurry can be made uniform so that the electrode slurry is discharged uniformly to each of the branch pipes 30.

[0026] The inclination of the main pipe 20 may be inclined at an acute angle to the horizontal plane, and the inclination can be changed in consideration of the type and viscosity of the electrode slurry, etc. For example, the inclination can be adjusted to 5 degrees or more and 25 degrees or less, preferably 10 degrees or more and 20 degrees or less.

[0027] The main pipe 20 may include a connecting pipe 21 connected to the tank 10, and a straight pipe 23 coupled to the connecting pipe 21 and connected to the two or more branch pipes 30. In this case, an angle between a plane perpendicular to the gravity direction and a central axis of the straight pipe 23 may be adjusted to 5 degrees or more and 25 degrees or less, preferably 10 degrees or more and 20 degrees or less.

[0028] One end of the main pipe 20 is connected to the tank 10, and a side portion of the main pipe 20 is connected to at least one branch pipe 30. The electrode slurry discharged from the tank 10 is moved to the branch pipe 30, in other words, the electrode slurry discharged from the tank 10 is moved to a pump (not shown) individually provided in the branch pipe 30 solely by the head of the electrode slurry, i.e., the pressure force due to height. By arranging the main pipe 20 at an angle, the electrode slurry discharged from the tank can be transferred to each individual branch pipe 30 solely by the head of the electrode slurry, i.e., the pressure force due to height, at a more uniform flow rate, to the pump (not shown) individually provided in the branch pipe 30.

[0029] A step is also formed in the height of a pump (not shown) located at the connection point between each branch pipe 30 and the main pipe 20, so that an equal flow rate can be discharged to each branch pipe 30 regardless of the physical properties of the electrode slurry.

[0030] The head of the electrode slurry discharged from the tank is supplied to a pump (not shown) provided individually in the branch pipe 30. In other words, the pressure force due to the height of the electrode slurry is A distance (A) between one end of the main pipe connected to the tank and a point where the branch pipe and the main pipe are connected on a plane perpendicular to the direction of gravity; The gravity direction can be adjusted through the ratio of the height difference (B) between one end of the main pipe connected to the tank and the point where the branch pipe and the main pipe are connected.

[0031] First, in the conventional electrode slurry supplying apparatus, if we check the ratio of A:B through FIG. 1, since the heights of all the branch pipes are equal, B is constant, A1:B is 4:1, A2:B is 5:1, A3:B is 6:1, and A4:B is 7:1.

[0032] In contrast, the electrode slurry providing device 1 according to the present specification is as follows: A distance (A) between one end of the main pipe connected to the tank and a point where the branch pipe and the main pipe are connected on a plane perpendicular to the direction of gravity; The ratio of the height difference (B) between one end of the main pipe connected to the tank and the point where the branch pipe and the main pipe are connected in the gravity direction is adjusted to 2:1 to 3:1.

[0033] In the electrode slurry providing apparatus 1 according to the present specification shown in FIG. 2, when checking the ratios of A:B, A1:B1, A2:B2, A3:B3 and A4:B4 are 2:1 to 3:1, respectively.

[0034] The A1:B1 is the ratio of the distance (A1) between one end of the main pipe 20 connected to the tank 10 and the point where the first branch pipe 30' and the main pipe 20 are connected on a plane perpendicular to the direction of gravity, to the height difference (B1) between one end of the main pipe 20 connected to the tank 10 and the point where the first branch pipe 30' and the main pipe 20 are connected in the direction of gravity.

[0035] The A2:B2 is the ratio of the distance (A2) between one end of the main pipe 20 connected to the tank 10 and the point where the second branch pipe 30'' and the main pipe 20 are connected on a plane perpendicular to the direction of gravity, to the height difference (B2) between one end of the main pipe 20 connected to the tank 10 and the point where the second branch pipe 30'' and the main pipe 20 are connected in the direction of gravity.

[0036] The A3:B3 is the ratio of the distance (A3) between one end of the main pipe 20 connected to the tank 10 and the point where the third branch pipe 30''' and the main pipe 20 are connected on a plane perpendicular to the direction of gravity, to the height difference (B3) between one end of the main pipe 20 connected to the tank 10 and the point where the third branch pipe 30''' and the main pipe 20 are connected in the direction of gravity.

[0037] The A4:B4 is the ratio of the distance (A4) between one end of the main pipe 20 connected to the tank 10 and the point where the fourth branch pipe 30'''' and the main pipe 20 are connected on a plane perpendicular to the direction of gravity, to the height difference (B4) between one end of the main pipe 20 connected to the tank 10 and the point where the fourth branch pipe 30'''' and the main pipe 20 are connected in the direction of gravity.

[0038] At least one branch pipe 30 can be connected to a side portion of the main pipe 20. Specifically, two or more branch pipes 30 can be provided, three or more branch pipes can be provided, and two to ten branch pipes can be provided. Since a more uniform flow rate can be supplied regardless of the physical properties of the liquid than in the past, the number of branch pipes that can supply a uniform flow rate from one tank is increased compared to the past.

[0039] Another embodiment of the present specification provides a coating device that discharges the electrode slurry provided from the electrode slurry providing device. The type and form of the coating device are not particularly limited as long as it can discharge the electrode slurry provided from the electrode slurry providing device and coat it on a substrate. For example, the coating device may be a comma coater, a spin coater, a slot die coater, etc.

[0040] At this time, the coating device may be connected to one branch pipe of the electrode slurry supplying device, and the coating devices connected to each branch pipe may be different or the same.

[0041] Another embodiment of the present specification provides a die coater for discharging the electrode slurry provided from the electrode slurry providing device described above. The die coater includes two or more dies and a shim provided between the dies so that the electrode slurry can be discharged.

[0042] Those skilled in the art will understand that the present invention can be embodied in other specific forms without changing the technical idea or essential features of the present invention. Therefore, the above-described embodiments are illustrative in all respects and are not limiting. The scope of the present invention is defined by the claims rather than the above detailed description, and various embodiments derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0043] 1: Electrode slurry supply device 10: Tank 20: Main piping 21: Connecting pipe 23: Straight tube 30: Branch piping 30': First branch pipe 30'': Second branch pipe 30''': 3rd branch pipe 30'': 4th branch pipe

Claims

1. a tank for containing the electrode slurry; A main pipe connected at one end to the tank; and The electrode slurry is discharged from the main pipe. The further away from the tank the point where the branch pipe and the main pipe are connected, the lower the point where the branch pipe and the main pipe are connected; an electrode slurry providing apparatus including two or more pumps each located at a point where the branch pipe and the main pipe are connected;

2. A distance (A) between one end of the main pipe connected to the tank and a point where the branch pipe and the main pipe are connected on a plane perpendicular to the direction of gravity; 2. The electrode slurry providing apparatus of claim 1, wherein a ratio of a height difference (B) between one end of the main pipe connected to the tank and a point where the branch pipe and the main pipe are connected in a gravity direction is 2:1 to 3:

1.

3. The electrode slurry providing apparatus according to claim 1 , wherein the main pipe includes a connecting pipe connected to the tank, and a straight pipe coupled to the connecting pipe and connected to the two or more branch pipes.

4. 4. The electrode slurry providing apparatus according to claim 3, wherein an angle between a plane perpendicular to the direction of gravity and a central axis of the straight tube is 5 degrees or more and 25 degrees or less.

5. A coating apparatus that discharges an electrode slurry provided from the electrode slurry providing apparatus according to any one of claims 1 to 4.

6. A die coater that discharges an electrode slurry provided from the electrode slurry providing device according to any one of claims 1 to 4.

7. A die coater that ejects an electrode slurry provided from an electrode slurry providing device, The electrode slurry providing device is a tank for containing the electrode slurry; A main pipe connected at one end to the tank; and The electrode slurry is discharged from the main pipe. A die coater, wherein the point where the branch pipe and the main pipe are connected becomes gradually lower as the point where the branch pipe and the main pipe are connected becomes farther from the tank.

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