Reagent for rapidly cleaning residual substances of cold pressing roller and use method of reagent

Abstract

The invention discloses a reagent for rapidly cleaning residual substances of a cold pressing roller, and relates to the technical field of battery processing, the reagent comprises the following components: a strong alkaline solution, an organic solvent with large polarity, polyethylene glycol monomethyl ether and water, the alkaline solution is NaOH or KOH, the organic solvent is absolute ethyl alcohol or methanol, and the water is distilled water. The ratio of the alkaline solution in the raw materials of the reagent is 10-20%, the ratio of the organic solvent in the raw materials of the reagent is 30-40%, the ratio of the methoxypolyethylene glycol in the raw materials of the reagent is 10-20%, and the ratio of the water in the raw materials of the reagent is 20-50%. The cold pressing roller cannot be damaged, the production efficiency of the cold pressing procedure is improved, the smoothness and flatness of the surface of the cold pressing pole piece are guaranteed, the service life of the cold pressing roller is prolonged, the maintenance cost is greatly saved, and meanwhile the whole reagent is easy in raw material obtaining, convenient to use and convenient to operate.

Description

Technical Field

[0001] The invention relates to the technical field of battery processing, and in particular to a reagent for quickly cleaning residual substances on a cold pressing roller and a use method thereof. Background Art

[0002] The process of lithium-ion battery mainly includes slurrying, coating, cold pressing, die-cutting and stripping, winding, shelling, liquid injection, welding, formation, etc. Among them, pole piece cold pressing is an important link in the production process of lithium-ion battery. Its purpose is to obtain pole pieces that meet the design requirements. Rolling is a very necessary process. After the pole piece is coated and dried, the peeling strength between the active material and the current collector foil is very low. At this time, it needs to be rolled to enhance the bonding strength between the active material and the foil to prevent peeling during electrolyte immersion and battery use. The rolling process can keep the surface of the pole piece smooth and flat, thereby preventing the hidden danger of battery short circuit caused by burrs on the surface of the pole piece piercing the diaphragm and improving the energy density of the battery; the rolling process can also compact the electrode material coated on the pole piece current collector, thereby reducing the volume of the pole piece, increasing the energy density of the battery, and improving the cycle life and safety performance of the lithium battery.

[0003] In the actual lithium battery negative electrode slurry process, SBR (styrene butadiene rubber) is usually used to improve the bonding performance between the slurry itself and the current collector. Since the surface of SBR is carboxyl-modified and hydrophilic, it can be stably suspended in water, but its adsorption to graphite is poor, resulting in the floating segregation of SBR during the drying process. During the cold pressing process of the pole piece, the roller will stick and it is difficult to remove. Usually, water or alcohol solvent is used for wiping, and the wiping effect is poor, which affects the quality of the subsequent cold pressing of the pole piece. In the industry, there is even a phenomenon of scrapped cold pressing rollers, which seriously causes a waste of resources. Based on the problems that the adhesive material on the cold pressing roller is difficult to remove and the maintenance cost is high, a reagent and a method for using the residual material on the cold pressing roller are proposed. Summary of the invention

[0004] The purpose of the present invention is to solve the problems in the prior art and to propose a reagent for quickly cleaning residual substances on a cold pressing roller and a method for using the reagent.

[0005] A reagent for quickly cleaning residual substances on a cold pressing roller comprises the following components: a strong alkaline solution, an organic solvent with a relatively large polarity, polyethylene glycol monomethyl ether and water.

[0006] Preferably, the alkaline solution is NaOH or KOH.

[0007] Preferably, the organic solvent is anhydrous ethanol or methanol.

[0008] Preferably, the proportion of alkaline solution in the reagent raw material is 10-20%, the proportion of organic solvent in the reagent raw material is 30-40%, the proportion of polyethylene glycol monomethyl ether in the reagent raw material is 10-20%, and the proportion of water in the reagent raw material is 20-50%.

[0009] Preferably, the proportion of alkaline solution in the reagent raw material is 10-20%, the proportion of organic solvent in the reagent raw material is 30-40%, the proportion of polyethylene glycol monomethyl ether in the reagent raw material is 10-20%, and the proportion of water in the reagent raw material is 20-50%.

[0010] The present invention also proposes a method for using a reagent to quickly clean residual substances on a cold pressing roller. The reagent is wetted with dust-free paper and then spread flat on the area of ​​the cold pressing roller with residual substances. After standing for 5 minutes, it is wiped with clean dust-free paper and then wiped with anhydrous ethanol.

[0011] Compared with the prior art, the present invention has the following advantages:

[0012] 1. The reagent and the method of use proposed in the present invention can quickly clean the residual substances on the cold pressing roller, and the reagent raw materials are easy to obtain, easy to use, and convenient to operate.

[0013] 2. The present invention cleans the cold pressing roller without damaging the cold pressing roller, thereby improving the production efficiency of the cold pressing process, ensuring the smoothness and flatness of the surface of the cold pressed electrode, and increasing the service life of the cold pressing roller, thereby greatly saving maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent in Example 1 of the present invention.

[0015] Figure 2 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent in Example 2 of the present invention.

[0016] Figure 3 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent in Example 3 of the present invention.

[0017] Figure 4 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent of Example 4 in the present invention.

[0018] Figure 5 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent of Comparative Example 1 in the present invention.

[0019] Figure 6 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent of Comparative Example 2 in the present invention.

[0020] Figure 7 This is a comparison of the before and after photos of the cold press roller being wiped with the reagent of comparative example 3 in the present invention. DETAILED DESCRIPTION

[0021] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0022] A reagent for quickly cleaning residual substances on a cold pressing roller comprises the following components: a strong alkaline solution, an organic solvent with a relatively large polarity, polyethylene glycol monomethyl ether and water.

[0023] The alkaline solution is NaOH or KOH.

[0024] The organic solvent is anhydrous ethanol or methanol.

[0025] The proportion of alkaline solution in the reagent raw material is 10-20%, the proportion of organic solvent in the reagent raw material is 30-40%, the proportion of polyethylene glycol monomethyl ether in the reagent raw material is 10-20%, and the proportion of water in the reagent raw material is 20-50%.

[0026] A method for using a reagent for quickly cleaning residual substances on a cold pressing roller. The reagent is wetted with dust-free paper and then spread flat on an area of ​​the cold pressing roller with residual substances. After standing for 5 minutes, the area is wiped with clean dust-free paper and then wiped with anhydrous ethanol.

[0027] The medium-strong alkaline solution of the reagent raw material can undergo a saponification reaction with a polymer compound binder such as SBR, converting it into a saponified product, thereby reducing the viscosity of the binder; the organic solvent with a relatively large polarity in the reagent raw material can clean the oil stains on the surface of the cold press roller; polyethylene glycol monomethyl ether has good water solubility and lubricity, and can quickly penetrate into the binder and the surface of the cold press roller to reduce the viscosity of the binder; water is used as a solvent to achieve a cleaning effect.

[0028] Example 1

[0029] Components of the reagent: 15% NaOH, 40% anhydrous ethanol, 20% polyethylene glycol monomethyl ether and 25% water;

[0030] S1. Mix 15% NaOH + 40% anhydrous ethanol + 20% polyethylene glycol monomethyl ether + 25% water to prepare a reagent;

[0031] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0032] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0033] Example 2

[0034] Components of the reagent: 10% NaOH, 30% anhydrous ethanol, 10% polyethylene glycol monomethyl ether and 50% water;

[0035] S1. Mix 10% NaOH + 30% anhydrous ethanol + 10% polyethylene glycol monomethyl ether + 50% water to prepare a reagent;

[0036] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0037] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0038] Example 3

[0039] Components of the reagent: 15% KOH, 40% anhydrous ethanol, 20% polyethylene glycol monomethyl ether and 25% water;

[0040] S1. Compared with Example 1, the NaOH in the formula raw material is replaced with KOH to prepare the reagent;

[0041] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0042] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0043] Example 4

[0044] Components of the reagent: 15% NaOH, 40% methanol, 20% polyethylene glycol monomethyl ether and 25% water;

[0045] S1. Compared with Example 1, the anhydrous ethanol in the formula raw material is replaced with methanol to prepare the reagent;

[0046] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0047] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0048] Comparative Example 1

[0049] Components of the reagent: 15% NaOH, 40% anhydrous ethanol and 45% water;

[0050] S1. Compared with Example 1, the polyethylene glycol monomethyl ether in the formula raw materials is eliminated to prepare the reagent;

[0051] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0052] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0053] Comparative Example 2

[0054] Components of the reagent: 15% NaOH, 20% polyethylene glycol monomethyl ether and 65% water;

[0055] S1. Compared with Example 1, the anhydrous ethanol in the formula raw materials is eliminated to prepare the reagent;

[0056] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0057] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0058] Comparative Example 3

[0059] Components of the reagent: 40% anhydrous ethanol, 20% polyethylene glycol monomethyl ether and 40% water;

[0060] S1. Compared with Example 1, the NaOH in the formula raw materials is eliminated to prepare the reagent;

[0061] S2. Wet the dust-free paper and spread it flat on the area where the cold press roller has residual material;

[0062] S3. After standing for 5 minutes, wipe it with clean dust-free paper, and then wipe the cold pressing roller with anhydrous ethanol.

[0063] Result analysis:

[0064] Reference Figure 1-7 As shown, Example 1 is a preferred example of the present invention, and the residual substances on the surface of the cold press roller are completely wiped clean, which can meet the technical requirements;

[0065] In Example 2, the contents of NaOH, anhydrous ethanol, and polyethylene glycol monomethyl ether were lowered, and the residual substances on the surface of the cold press roller were completely wiped clean, which met the technical requirements;

[0066] In Example 3, NaOH in the reagent raw material is replaced with KOH, and the residual substances on the surface of the cold press roller are completely wiped clean, which can meet the technical requirements;

[0067] In Example 4, the anhydrous ethanol in the reagent raw material is replaced with methanol, and the residual substances on the surface of the cold press roller are completely wiped clean, which can meet the technical requirements;

[0068] In Comparative Example 1, polyethylene glycol monomethyl ether was removed from the reagent raw materials, and residual substances were present on the surface of the cold press roller that were not wiped clean;

[0069] In Comparative Example 2, anhydrous ethanol was eliminated from the reagent raw materials, and residual substances were present on the surface of the cold press roller that were not wiped clean;

[0070] In Comparative Example 3, NaOH was eliminated from the reagent raw materials, and residual substances existed on the surface of the cold-pressing roller and were not wiped clean.

[0071] It can be seen from the above experimental results that the reagent of the present invention does not have a good cleaning effect when residual substances exist on the surface of the cold press roller after any component of the strong alkaline solution, the organic solvent with high polarity and the polyethylene glycol monomethyl ether is missing.

[0072] In summary, the reagent and the method of use proposed in the present invention can quickly clean the residual substances on the cold pressing roller without causing damage to the cold pressing roller, greatly saving the maintenance cost, and the reagent raw materials are easy to obtain, easy to use, and convenient to operate.

[0073] It is known from common technical knowledge that the present invention can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the above disclosed embodiments are only illustrative in all respects and are not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are included in the present invention.

Claims

1. A reagent for quickly cleaning residual substances on cold pressing rollers, characterized in that: The reagent comprises the following components: a strong alkaline solution, an organic solvent with a relatively large polarity, polyethylene glycol monomethyl ether and water.

2. The reagent for quickly cleaning residual substances on cold pressing rollers according to claim 1, characterized in that: The alkaline solution is NaOH or KOH.

3. The reagent for quickly cleaning residual substances on cold pressing rollers according to claim 1, characterized in that: The organic solvent is anhydrous ethanol or methanol.

4. The reagent for quickly cleaning residual substances on cold pressing rollers according to claim 1, characterized in that: The proportion of alkaline solution in the reagent raw material is 10-20%, the proportion of organic solvent in the reagent raw material is 30-40%, the proportion of polyethylene glycol monomethyl ether in the reagent raw material is 10-20%, and the proportion of water in the reagent raw material is 20-50%.

5. A method for using a reagent for quickly cleaning residual substances on a cold pressing roller according to any one of claims 1 to 4, characterized in that: The reagent was moistened with dust-free paper and then spread flat on the area of ​​the cold press roller with residual substances. After standing for 5 minutes, it was wiped with clean dust-free paper and then wiped with anhydrous ethanol.

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