A current collector recovery method and recovery equipment

Abstract

The present invention relates to a method for recycling a current collector, comprising the following steps: S1, laminating the A surface of the waste current collector with the A surface of the normal current collector; S2, plating through an acid plating tank and then a conductive tank; S3, drying; S4, peeling, obtaining separated waste current collectors and a normal current collector with single-sided coating; S5, laminating the B surface of the waste current collector with the B surface of the normal current collector; S6, repeating the above steps S2-S4; S7, obtaining a recyclable current collector and a normal current collector with double-sided coating; S8, recycling the current collector, crushing, and remaking. The present invention laminates and peels the waste current collector with the normal current collector twice, and processes one side each time with the same processing steps, so that the metal on one side of the waste current collector is dissolved and the one side of the normal current collector is plated, so that the current collector film is produced while the waste current collector is effectively processed, and the recycling and production are carried out simultaneously, which greatly improves the efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of current collectors, and in particular to a current collector recovery method and recovery equipment. Background Art

[0002] The current collector is one of the important components of the battery and plays the role of gathering current. Since the weight of the current collector plays a crucial role in the energy density of the battery, the current collector of the existing battery is lighter and thinner than the previous current collector. The method to reduce the weight is to stack a metal layer on a layer of polymer film to form a thin current collector.

[0003] The existing current collector production process often requires vacuum coating to deposit metal on the surface of the film, but the vacuum coating process has the following problems: since the energy absorbed by the material to be evaporated is very high, there is a certain probability that the film will be burned through when layered on it, making the product unqualified and greatly wasting raw materials.

[0004] Therefore, how to effectively recycle discarded current collectors and reduce losses for enterprises has become an urgent problem to be solved in the industry. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a current collector recovery method and recovery equipment.

[0006] The technical solution of the present invention is as follows:

[0007] A method for recovering a current collector, characterized by comprising the following steps:

[0008] S1, laminating the A surface of the waste current collector and the A surface of the normal current collector to obtain a first composite film;

[0009] S2, passing the first composite film through an acid plating tank and a conductive tank in sequence for corrosion and electroplating;

[0010] S3, drying the first composite film;

[0011] S4, peeling off the first composite film to obtain a separated waste current collector and a normal current collector with a single-side coating;

[0012] S5, laminating the B surface of the waste current collector and the B surface of the normal current collector to obtain a second composite film;

[0013] S6, repeating the above steps S2-S4 for the second composite film to complete coating, drying and peeling;

[0014] S7, obtaining a recyclable current collector and a normal current collector with double-sided coating;

[0015] S8. Recover, crush and remake the recyclable current collector.

[0016] The present invention according to the above solution is characterized in that the step S1 further comprises:

[0017] S101, the waste current collector and the normal current collector are passed through respective unwinding rollers for film conveying;

[0018] S102, the waste current collector and the normal current collector are laminated on one side through two extrusion composite rollers.

[0019] The present invention according to the above solution is characterized in that the step S2 further comprises:

[0020] S201, the first composite film passes through an acid plating tank to corrode and dissolve the metal on one side of the waste current collector;

[0021] S202, the first composite film passes through the conductive tank, and its normal current collector side contacts the conductive roller, forming an electroplating loop in the acid plating tank, and electroplating is performed on the normal current collector side.

[0022] The present invention according to the above scheme is characterized in that the acid plating tank in step S2 contains a plating solution, and the plating solution is acidic.

[0023] The present invention according to the above scheme is characterized in that step S8 comprises the following steps:

[0024] S801, placing the recyclable fluid obtained in step S7 into a pulverizer;

[0025] S802, drying to obtain current collector recycled material;

[0026] S803, the current collector recycled material is mixed with polymethyl methacrylate, phthalate, alkyl aryl phosphate, and solvent, and put into a film making machine to obtain a film;

[0027] S804, double-sided evaporation of the thin film to obtain a current collector.

[0028] Furthermore, in step S802, the drying temperature is 70° C. and the drying time is 24 hours.

[0029] Furthermore, in step S803, the film making machine is a casting machine, and the thickness of the obtained film is 3-6 um.

[0030] The present invention according to the above solution is characterized in that the step S8 further includes:

[0031] S9, pick out the unqualified discarded current collectors and repeat steps S1-S8.

[0032] On the other hand, the present invention also provides a recycling device for implementing the collector recycling method of the above-mentioned scheme, characterized in that it includes two extrusion composite rollers, an acid plating tank, a conductive tank, a drying box and a stripping device, the two extrusion composite rollers are used to bond the waste collector and the normal collector to form a composite film, and the composite film is released through the extrusion composite rollers, passes through the acid plating tank, the conductive tank and the drying box in turn, and is finally separated by the stripping device.

[0033] The present invention according to the above scheme is characterized in that two parallel conductive rollers are provided in the conductive groove, and the conductive rollers are in contact with the normal current collector side of the composite film.

[0034] Furthermore, an extrusion roller is provided above the conductive roller.

[0035] The present invention according to the above scheme has the following beneficial effects:

[0036] The present invention laminates and peels off the waste current collector and the normal current collector for a second time, and processes one side at a time with the same processing steps. In this process, the metal on one side of the waste current collector is dissolved, and the normal current collector side is plated. This achieves the production of the current collector film while effectively processing the waste current collector, and carries out recycling and production at the same time, which greatly improves efficiency and prevents waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a flowchart of the method of the present invention;

[0038] Figure 2 It is a schematic diagram of the structure of the recycling equipment of the present invention.

[0039] In the figure, 1, extrusion composite roller; 2, acid plating tank; 3, conductive tank; 4, conductive roller; 5, extrusion roller; 6, drying box; 7, stripping device; 81, first roller; 82, second roller; 83, third roller; 84, fourth roller;

[0040] 101. Waste current collector; 102. Normal current collector. DETAILED DESCRIPTION

[0041] In order to better understand the purpose, technical solution and technical effect of the present invention, the present invention is further explained below in conjunction with the accompanying drawings and embodiments. At the same time, it is stated that the embodiments described below are only used to explain the present invention and are not used to limit the present invention.

[0042] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0043] The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. "Several" means two or more, unless otherwise clearly and specifically defined.

[0044] like Figure 1 As shown, a method for recycling a current collector comprises the following steps:

[0045] S1, laminating the A surface of the waste current collector and the A surface of the normal current collector to obtain a first composite film;

[0046] In this embodiment, step S1 further includes:

[0047] S101, the waste current collector and the normal current collector are passed through respective unwinding rollers for film conveying;

[0048] S102, laminating the opposite surfaces of the waste current collector and the normal current collector together through two extrusion laminating rollers, that is, completing single-sided lamination to form a first composite film.

[0049] S2, passing the first composite film through an acid plating tank and a conductive tank in sequence, and performing corrosion and electroplating at the same time;

[0050] In this embodiment, step S2 further includes:

[0051] S201, the first composite film passes through an acid plating tank, a second roller and titanium blue are arranged at the bottom of the acid plating tank, a copper ball as an anode is placed in the titanium blue, and an acidic electroplating solution is placed in the acid plating tank. The acidic substance in the electroplating solution will corrode the metal on one side of the waste current collector, thereby dissolving in the electroplating solution;

[0052] S202, the first composite film passes through a conductive tank, in which a conductive roller is provided, and the conductive roller contacts one side of the normal current collector of the first composite film (at this time, the B side of the normal current collector), so that the B side of the normal current collector serves as the cathode, and because the copper ball in the acid plating tank serves as the anode, combined with the electroplating solution, an electroplating circuit can be formed, and the B side of the normal current collector is plated in the acid plating tank.

[0053] S3, drying the first composite film;

[0054] S4, peeling off the first composite film to obtain a separated waste current collector and a normal current collector with a single-side coating;

[0055] S5, laminating the B surface of the waste current collector and the B surface of the normal current collector to obtain a second composite film;

[0056] S6, repeating the above steps S2-S4 for the second composite film to complete coating, drying and peeling;

[0057] In this embodiment, step S4 uses a stripping device to separate the first composite film. At this time, the B surface of the waste current collector and the B surface of the normal current collector are processed; entering step S5, the treated B surfaces of the two are bonded together to expose the A surface to form a second composite film, and the A surface of the waste current collector and the A surface of the normal current collector are processed through an acid plating tank, a conductive tank, and a drying box, and then stripped;

[0058] S7. Obtain a recyclable current collector and a normal current collector with double-sided coating.

[0059] Therefore, the present invention laminates and peels off the waste current collector and the normal current collector for a second time, and processes one side each time with the same processing steps. In this process, the metal on one side of the waste current collector is dissolved and the normal current collector is plated, thereby achieving the production of the current collector film while effectively processing the waste current collector.

[0060] In the present invention, the steps of recycling the current collector are: S8, recycling, crushing and remaking the recyclable current collector, which specifically includes the following steps:

[0061] S801, placing the recyclable fluid obtained in step S7 into a pulverizer;

[0062] S802, drying to obtain the current collector recycled material, wherein the drying temperature is 70° C. and the drying time is 24 hours;

[0063] S803, the current collector recycled material is mixed with 20-30% polymethyl methacrylate, 10-20% phthalate, 3-5% alkyl aryl phosphate, and 30-47% solvent in a weight ratio, and put into a film making machine for film making, wherein the film making machine is a casting machine, and finally a film with a thickness of 3-6um is formed; wherein the solvent is a mixture of tetrahydrofuran and toluene, and the weight ratio of the two is 2:1.

[0064] S804, double-sided evaporation of the thin film to obtain a current collector.

[0065] Due to the double-sided evaporation process, the evaporated material melts and evaporates at a high temperature. When it is layered on the current collector, there is a certain probability that holes will be burned in the current collector film, resulting in unqualified products. Therefore, after step S8, it also includes: S9, picking out the unqualified discarded current collector, and repeating steps S1-S8.

[0066] like Figure 2As shown, on the other hand, the present invention also provides a recycling device for implementing the collector recycling method of the above-mentioned scheme, including two extrusion composite rollers 1, an acid plating tank 2, a conductive tank 3, a drying box 6 and a stripping device 7. The two extrusion composite rollers are used to bond the waste collector 101 and the normal collector 102 to form a composite film, and pass through the acid plating tank 2, the conductive tank 3 and the drying box 6 in sequence, and finally pass through the stripping device 7 for separation.

[0067] In this embodiment, two parallel conductive rollers 4 are provided in the conductive slot, and the conductive rollers 4 are in contact with the normal current collector side of the composite film. An extrusion roller 5 is provided above the conductive roller 4 to prevent the electroplating solution from remaining on the conductive roller and scratching the film.

[0068] In this embodiment, a first roller 81 and a third roller 83 are provided at both ends of the opening of the acid plating tank, a second roller 82 is provided inside the acid plating tank, and a fourth roller 84 is provided between the conductive tank and the drying box. The above rollers can effectively flatten the film and turn the film at the same time.

[0069] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for recovering a current collector, characterized in that: The following steps are involved: S1, laminating the A surface of the waste current collector and the A surface of the normal current collector to obtain a first composite film; S2, passing the first composite film through an acid plating tank and a conductive tank in sequence for corrosion and electroplating; S3, drying the first composite film; S4, peeling off the first composite film to obtain a separated waste current collector and a normal current collector with a single-side coating; S5, laminating the B surface of the waste current collector and the B surface of the normal current collector to obtain a second composite film; S6, repeating the above steps S2-S4 for the second composite film to complete coating, drying and peeling; S7, obtaining a recyclable current collector and a normal current collector with double-sided coating; S8. Recover, crush and remake the recyclable current collector.

2. The current collector recovery method according to claim 1, characterized in that: Step S1 also includes: S101, the waste current collector and the normal current collector are passed through respective unwinding rollers for film conveying; S102, the waste current collector and the normal current collector are laminated on one side through two extrusion composite rollers.

3. The current collector recovery method according to claim 1, characterized in that: Step S2 also includes: S201, the first composite film passes through an acid plating tank to corrode the metal on one side of the waste current collector; S202, the first composite film passes through the conductive tank, and its normal current collector side contacts the conductive roller, forming an electroplating loop in the acid plating tank, and electroplating is performed on the normal current collector side.

4. The method for recovering a current collector according to claim 1, characterized in that: The acid plating tank in step S2 contains an acidic electroplating solution.

5. The method for recovering a current collector according to claim 1, characterized in that: Step S8 includes the following steps: S801, placing the recyclable fluid obtained in step S7 into a pulverizer; S802, drying to obtain current collector recycled material; S803, the current collector recycled material is mixed with polymethyl methacrylate, phthalate, alkyl aryl phosphate, and solvent, and put into a film making machine to obtain a film; S804, double-sided evaporation of the thin film to obtain a current collector.

6. The method for recovering the current collector according to claim 5, characterized in that: In step S802, the drying temperature is 70°C and the drying time is 24 hours.

7. The method for recovering a current collector according to claim 5, characterized in that: In step S803, the film making machine is a casting machine, and the thickness of the film obtained is 3-6 um.

8. The method for recovering a current collector according to claim 1, characterized in that: After step S8, the following steps are also included: S9, pick out the unqualified discarded current collectors and repeat steps S1-S8.

9. A recycling device for implementing the current collector recycling method according to any one of claims 1 to 8, characterized in that: It includes two extrusion composite rollers, an acid plating tank, a conductive tank, a drying box and a stripping device. The two extrusion composite rollers are used to bond the waste current collector and the normal current collector to form a composite film. The composite film is released through the extrusion composite rollers, passes through the acid plating tank, the conductive tank and the drying box in sequence, and is finally separated by the stripping device.

10. The recycling device according to claim 9, characterized in that Two parallel conductive rollers are arranged in the conductive groove, and the conductive rollers are in contact with the normal current collector side of the composite film.

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