An apparatus for continuous deposition of carbon films on metal surfaces by capacitively coupled plasma
By using capacitively coupled plasma technology to continuously deposit carbon films on metal surfaces, the problems of low deposition efficiency, high cost, and poor bonding strength in existing technologies have been solved. This has enabled efficient and low-cost carbon film deposition, improved the performance of current collectors, and made it suitable for chemical energy storage devices such as secondary batteries and supercapacitors.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TENGXIAN TOPTECH ELECTRONIC CO LTD
- Filing Date
- 2025-05-29
- Publication Date
- 2026-06-16
AI Technical Summary
Existing methods for depositing carbon films on current collector surfaces suffer from problems such as low deposition efficiency, high cost, low bonding strength, and high equipment maintenance costs, making it difficult to meet the needs of industrial continuous production.
Using capacitively coupled plasma technology, a vacuum system consisting of a vacuum chamber, an oil diffusion pump, a Roots pump, and a mechanical pump, combined with an asymmetric electrode and a mixing chamber, is used to achieve continuous deposition of carbon films, improve the uniformity of gas distribution and the temperature of the coating area, and enhance the adhesion between the carbon film and the metal strip.
It enables continuous roll-to-roll production of carbon films, improving production efficiency and carbon film quality, enhancing the corrosion resistance and conductivity of current collectors, meeting the requirements of high energy density and high power density energy storage devices, and extending battery life.
Smart Images
Figure CN224362872U_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of thin film preparation technology, and in particular to an apparatus for continuously depositing carbon films on metal surfaces via capacitively coupled plasma. Background Technology
[0002] Due to its high conductivity, high specific surface area, high temperature stability, and good corrosion resistance, carbon materials are used to modify the surface of current collectors (including aluminum foil, copper foil, and nickel foil) to improve their corrosion resistance in batteries, while also maintaining good conductivity.
[0003] Currently, the most common surface modification of current collectors involves depositing carbon films on the current collector surface, primarily through physical vapor deposition (PVD), carbon coating, and chemical vapor deposition (CVD). PVD suffers from low deposition efficiency and high cost, hindering its widespread adoption. Carbon coating is low-cost, but requires the addition of binders to the coating slurry, increasing the coating's internal resistance. Furthermore, the bonding strength between the carbon coating and the current collector body is weak, leading to easy detachment over long-term use, further increasing battery internal resistance and causing failure. In traditional thermochemical vapor deposition (CVD) processes, the carbon source decomposition temperature is generally high, requiring high-temperature decomposition of the carbon source gas to deposit carbon atoms onto the current collector surface. In industrial continuous production, equipment needs to maintain high temperatures for extended periods, resulting in high operating costs for components and equipment. Utility Model Content
[0004] The main purpose of this invention is to provide a device for continuously depositing carbon films on metal surfaces by capacitively coupling plasma.
[0005] The objective of this utility model can be achieved by adopting the following technical solution:
[0006] An apparatus for continuously depositing carbon films on metal surfaces via capacitively coupled plasma includes a vacuum chamber, an oil diffusion pump, a Roots pump, a mechanical pump, vacuum valves, vacuum pipes, take-up and untake-up rollers 1 and 2, an upper guide roller, a lower guide roller, a left electrode, a right electrode, a gas distribution pipe, a vacuum chamber partition, an inlet pipe, a gas mass flow meter, a mixing box, and a process gas inlet.
[0007] The vacuum chamber includes a trolley, a cavity with a vacuum gate, and the take-up and release roller one, the take-up and release roller two, the upper guide roller, the lower guide roller, the right electrode, and a portion of the gas distribution pipe corresponding to the right electrode, the vacuum chamber partition and the air inlet pipe are all installed on the trolley.
[0008] The left electrode and a portion of the gas distribution pipe, the inlet pipe, and the gas mass flow meter corresponding to the left electrode are installed on the cavity;
[0009] When the trolley closes with the cavity, the sealing plate on the trolley and the cavity together form the vacuum chamber. The take-up and release roller one, the take-up and release roller two, the upper guide roller, the lower guide roller, the left electrode, the right electrode and the gas distribution pipe are located inside the vacuum chamber through the vacuum gate.
[0010] The oil diffusion pump, the Roots pump, and the mechanical pump together form a vacuum pump group, which is connected to the vacuum chamber via the vacuum pipe equipped with the vacuum valve.
[0011] Preferably, the left electrode and the right electrode are arranged in pairs opposite each other in the vacuum chamber, and the distance between a pair of left electrodes and right electrodes arranged opposite each other is 3 to 10 cm.
[0012] Preferably, the width of the left electrode is 5 to 50 cm, and the width of the right electrode is 2 to 40 cm.
[0013] Preferably, the area of the left electrode is 1.1 to 3 times that of the right electrode.
[0014] Preferably, the mixing chamber is provided with two or more process gas inlets. After the process gases are mixed in the mixing chamber, they are respectively introduced into the gas distribution pipe located in the vacuum chamber through the pipeline equipped with the gas mass flow meter.
[0015] Preferably, the left and right electrodes, arranged opposite to each other, are electrically connected to a radio frequency power supply via wires.
[0016] Preferably, the gas distribution pipe is provided with a small hole, the diameter of which is 0.1 to 2 mm.
[0017] Preferably, the left electrode and the right electrode are composed of two parts: an electrode plate and a water-cooling plate, with the water-cooling plate disposed on the back of the left electrode and the right electrode.
[0018] The beneficial effects of this technology are:
[0019] 1. By combining the trolley and the cavity into a vacuum chamber, the equipment can move the winding and unwinding mechanism of the equipment into the external space during the production process. This allows on-site personnel to quickly change rolls with the help of tooling. At the same time, by setting up a continuous winding system, continuous roll-to-roll production of CVD carbon film is realized, which improves production efficiency.
[0020] 2. In some embodiments, by setting asymmetrical electrodes, that is, setting different widths for the left and right electrodes, the temperature of the coating area is increased, so that more carbon source gas is cracked in the plasma area, and the temperature of the metal strip in the plasma area can be increased, thereby improving the quality of carbon film deposition and increasing the bonding force between the carbon film and the metal strip.
[0021] 3. At the same time, the device is equipped with a gas mixing box. When using multiple process gases, different process gases are first quantitatively introduced into the gas mixing box. After the gases are mixed evenly in the gas mixing box, they are sent into the reaction zone between the left and right electrodes in the vacuum chamber through the gas inlet pipe. By setting multiple small holes on the gas distribution pipe, the uniformity of gas distribution after entering the vacuum chamber is improved, ensuring the uniformity of the deposited carbon film.
[0022] 4. After depositing a carbon film on the surface of metal strips (such as aluminum foil, etched aluminum foil, perforated aluminum foil, sintered aluminum foil, copper foil, nickel foil, perforated nickel or stainless steel foil, etc.), it can be used as a current collector for chemical energy storage devices such as secondary batteries and supercapacitors. It has corrosion resistance and good conductivity, which can effectively reduce internal resistance, meet the requirements of energy storage devices for high energy density and high power density, and extend battery life. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of a preferred embodiment of an apparatus for continuously depositing a carbon film on a metal surface by capacitively coupled plasma according to the present invention.
[0024] Figure 2 This is a schematic diagram of the separation of the trolley from the cavity in a preferred embodiment of an apparatus for continuously depositing a carbon film on a metal surface by capacitively coupled plasma according to the present invention.
[0025] Figure 3 In a preferred embodiment of the apparatus for continuously depositing carbon films on metal surfaces via capacitively coupled plasma according to the present invention, Figure 1 A magnified view of part A in the middle.
[0026] The annotations in the attached figures are explained as follows:
[0027] 1. Vacuum chamber; 2. Oil diffusion pump; 3. Roots pump; 4. Mechanical pump; 5. Vacuum valve; 6. Vacuum pipeline; 7. Take-up / release roller one; 8. Take-up / release roller two; 9. Upper guide roller; 10. Lower guide roller; 11. Left electrode; 12. Right electrode; 13. Gas distribution pipe; 14. Vacuum chamber partition; 15. Inlet pipe; 16. Gas mass flow meter; 17. Mixing box; 18. Process gas inlet; 19. Trolley; 20. Traction metal strip; 21. Vacuum gate; 22. Cavity; 23. Sealing plate; 111. Electrode plate; 122. Water-cooled plate; 131. Small hole. Detailed Implementation
[0028] To enable those skilled in the art to understand the technical solution of this utility model more clearly, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of this utility model is not limited thereto.
[0029] like Figure 1 The apparatus shown is for continuously depositing carbon films on metal surfaces via capacitively coupled plasma, characterized in that it comprises: a vacuum chamber 1, an oil diffusion pump 2, a Roots pump 3, a mechanical pump 4, a vacuum valve 5, a vacuum pipe 6, a take-up and release roller 1 7, a take-up and release roller 2 8, an upper guide roller 9, a lower guide roller 10, a left electrode 11, a right electrode 12, a gas distribution pipe 13, a vacuum chamber partition 14, an inlet pipe 15, a gas mass flow meter 16, a mixing box 17, and a process gas inlet 18;
[0030] like Figure 2 As shown, the vacuum chamber 1 includes a trolley 19, a cavity 22 with a vacuum gate 21, a take-up roller 7, a take-up roller 8, an upper guide roller 9, a lower guide roller 10, a right electrode 12 and a portion of the gas distribution pipe 13 corresponding to the right electrode 12, a vacuum chamber partition 14, an air inlet pipe 15, and is installed on the trolley 19.
[0031] The left electrode 11 and a portion of the gas distribution pipe 13, the inlet pipe 15, and the gas mass flow meter 16 corresponding to the left electrode 11 are installed on the cavity 22;
[0032] When the trolley 19 and the cavity 22 are closed, the sealing plate on the trolley 19 and the cavity 22 form a vacuum chamber 1. The take-up and release roller 1 7, the take-up and release roller 2 8, the upper guide roller 9, the lower guide roller 10, the left electrode 11, the right electrode 12, and the gas distribution pipe 13 are located inside the vacuum chamber 1 through the vacuum gate 21.
[0033] Vacuum chamber partition 14 divides vacuum chamber 1 into two parts: one part is the take-up and unwinding area where take-up and unwinding roller 1 7, take-up and unwinding roller 2 8 and multiple guide rollers are located, and the other part is the reaction coating area where multiple sets of electrodes, including left electrode 11 and right electrode 12, are located.
[0034] The above method helps to keep the metal strip clean in the winding and unwinding area, and also reduces the volume of the reaction coating area, making the distribution of reaction gas in the reaction coating area more uniform.
[0035] The oil diffusion pump 2, Roots pump 3, and mechanical pump 4 form a vacuum pump group, which is connected to the vacuum chamber 1 through a vacuum pipe 6 equipped with a vacuum valve 5.
[0036] In this embodiment, four left electrodes 11 and four right electrodes 12 are arranged in pairs facing each other and in parallel within the vacuum chamber 1, with a spacing of 4.5 cm between a pair of left electrodes 11 and right electrodes 12 arranged in opposite directions.
[0037] The width of the left electrode 11 is 12.5cm, the width of the right electrode 12 is 8cm, and the lengths of the left and right electrodes 12 are equal. In order to make the carbon film thickness on the surface of the metal strip uniform, the lengths of the left and right electrodes 12 must be greater than the width of the metal strip.
[0038] The left electrode 11 and the right electrode 12 are composed of two parts: an electrode plate 111 and a water-cooling plate 122. In this embodiment, the electrode plate 111 is made of graphite, and the water-cooling plate 122 is disposed on the back of the electrode plate 111 and has a flow channel inside, through which circulating cooling water can be introduced.
[0039] Before the equipment operates, the rolled metal strip is first installed on either the first unwinding roller or the second take-up roller 8. The metal strip 20 is then pulled through the guide roller between itself and the reaction coating zone, then passes between the left and right electrodes 12 in the reaction coating zone, and finally passes through another set of guide rollers to fix the metal strip sheet onto another take-up roller. In this embodiment, the metal strip used is a 20μm thick copper foil.
[0040] The apparatus for continuous carbon film deposition in this embodiment includes the following steps during the film deposition process:
[0041] 1. Close the trolley 19 and the cavity 22, and evacuate the vacuum chamber 1 to 2 to 5 × 10⁻³ Pa.
[0042] 2. Hydrogen, Ar and carbon source gas are introduced into the process gas inlet 18 on the mixing box 17 respectively. The flow ratio of hydrogen, Ar and carbon source gas is 2:5:3. The carbon source gas is one or more organic gases such as alkanes, alkenes, and alkynes. In this embodiment, ethylene is used as the carbon source gas. After the above three process gases are mixed in the mixing box 17, they are introduced into the gas distribution pipe 13 located in the vacuum chamber 1 through the pipeline equipped with gas mass flow meter 16. The orifice 131 on the gas distribution pipe 13 has a diameter of 0.2 mm.
[0043] The flow rate of the mixed gas introduced into each gas distribution pipe 13 is 100 sccm (standard-state cubic centimeter per minute, abbreviated as sccm).
[0044] 3. When the vacuum chamber pressure is 2-15 Pa, turn on the take-up and unwind motor to pull the metal strip 20 to move in the reaction coating area of the vacuum chamber 1. Then turn on the radio frequency power supply and deposit a carbon film at a frequency of 80 kHz and a radio frequency power of 5000 W.
[0045] The metal strip continuously passes through the reactive coating zone, is drawn onto the take-up and unwinding rollers after passing through the guide rollers, and is wound up to obtain a current collector modified by surface deposition of carbon film, which can be used in electrochemical energy storage devices.
[0046] The above are merely further embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed by this utility model, based on the technical solution and concept of this utility model, shall fall within the protection scope of this utility model.
Claims
1. An apparatus for continuously depositing carbon films on a metal surface via capacitively coupled plasma, characterized in that: It includes a vacuum chamber (1), an oil diffusion pump (2), a Roots pump (3), a mechanical pump (4), a vacuum valve (5), a vacuum pipe (6), a take-up and release roller 1 (7), a take-up and release roller 2 (8), an upper guide roller (9), a lower guide roller (10), a left electrode (11), a right electrode (12), a gas distribution pipe (13), a vacuum chamber partition (14), an inlet pipe (15), a gas mass flow meter (16), a mixing box (17), and a process gas inlet (18); The vacuum chamber (1) includes a trolley (19) and a cavity (22) with a vacuum gate (21). The take-up roller 1 (7), the take-up roller 2 (8), the upper guide roller (9), the lower guide roller (10), the right electrode (12), and a portion of the gas distribution pipe (13) corresponding to the right electrode (12), the vacuum chamber partition (14), and the air inlet pipe (15) are all installed on the trolley (19). The left electrode (11) and a portion of the gas distribution pipe (13), the air inlet pipe (15), and the gas mass flow meter (16) corresponding to the left electrode (11) are installed on the cavity (22); When the trolley (19) and the cavity (22) are closed, the sealing plate on the trolley (19) and the cavity (22) constitute the vacuum chamber (1). The take-up and release roller 1 (7), the take-up and release roller 2 (8), the upper guide roller (9), the lower guide roller (10), the left electrode (11), the right electrode (12) and the gas distribution pipe (13) are located inside the vacuum chamber (1) through the vacuum gate (21). The oil diffusion pump (2), the Roots pump (3), and the mechanical pump (4) form a vacuum pump group, and are connected to the vacuum chamber (1) through the vacuum pipe (6) equipped with the vacuum valve (5).
2. The apparatus for continuously depositing carbon films on metal surfaces via capacitively coupled plasma according to claim 1, characterized in that: The left electrode (11) and the right electrode (12) are arranged in pairs opposite each other in the vacuum chamber (1), and the distance between the pair of left electrodes (11) and right electrodes (12) is 3 to 10 cm.
3. The apparatus for continuously depositing carbon films on a metal surface via capacitively coupled plasma according to claim 2, characterized in that: The width of the left electrode (11) is 5 to 50 cm, and the width of the right electrode (12) is 2 to 40 cm.
4. The apparatus for continuously depositing carbon films on a metal surface via capacitively coupled plasma according to claim 3, characterized in that: The area of the left electrode (11) is 1.1 to 3 times that of the right electrode (12).
5. The apparatus for continuously depositing a carbon film on a metal surface via capacitively coupled plasma according to claim 4, characterized in that: The mixing chamber (17) is provided with two or more process gas inlets (18). After the process gas is mixed in the mixing chamber (17), it is introduced into the gas distribution pipe (13) located in the vacuum chamber (1) through the pipeline provided with the gas mass flow meter (16).
6. The apparatus for continuously depositing carbon films on a metal surface via capacitively coupled plasma according to claim 5, characterized in that: The left electrode (11) and the right electrode (12), which are arranged opposite to each other, are electrically connected to a radio frequency power supply via wires.
7. The apparatus for continuously depositing a carbon film on a metal surface via capacitively coupled plasma according to claim 6, characterized in that: The gas distribution pipe (13) is provided with a small hole (131), and the diameter of the small hole (131) is 0.1 to 2 mm.
8. The apparatus for continuously depositing a carbon film on a metal surface via capacitively coupled plasma according to claim 7, characterized in that: The left electrode (11) and the right electrode (12) are composed of two parts: an electrode plate (111) and a water-cooling plate (122). The water-cooling plate (122) is disposed on the back of the left electrode (11) and the right electrode (12).