Gradient porous bubble nickel current collector integrated bamboo-based thin layer graphite electrode

Abstract

The utility model discloses a gradient pore foam nickel current collector integration bamboo base thin layer graphite electrode belongs to the electrochemical material preparation technical field, including current collector, bamboo base thin layer graphite active layer, foam nickel framework and sleeve, bamboo base thin layer graphite active layer sets up on the outer wall of current collector bottom, foam nickel framework sets up on the outer wall of bamboo base thin layer graphite active layer, and the sleeve is connected and is sleeved on the current collector, and the inside cavity of sleeve is filled with electrolyte molten salt, the utility model electrode realizes the high -efficient graphitization of bamboo base biomass under low temperature (less than or equal to 900 DEG C) through the directional migration of ion in molten salt electrolysis process and the synergistic effect of pore, and the graphitization degree is as high as 50 70%, and is suitable for lithium electricity negative pole, super capacitor and other fields.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical material preparation technology, and specifically relates to the green synthesis of bamboo-based thin-layer graphite, specifically a gradient-pore nickel foam current collector integrated bamboo-based thin-layer graphite electrode. Background Technology

[0002] Biomass carbon materials have broad application prospects in the field of electrochemical energy storage due to their wide availability, low cost, and diverse structures. However, the graphitization of traditional biomass-derived carbon usually requires extremely high temperatures (≥2800°C), resulting in extremely high energy consumption (≥15 kWh / kg). Furthermore, high temperatures can easily lead to material structural collapse, a decrease in specific surface area, and deterioration of electrochemical performance. Although some studies have used metal catalysts (such as iron and nickel) to lower the graphitization temperature, the degree of graphitization is generally low (typically <20%), and residual metal impurities affect the cycling stability of the electrode.

[0003] Molten salt electrochemistry, as an emerging graphitization technology, can promote the ordering of carbon materials by driving ion migration through an electric field at relatively low temperatures (≤900°C), and has the potential to combine low-temperature energy saving with high graphitization degree. However, in existing methods, the interfacial bonding between the carbon precursor and the current collector is poor, the charge transport efficiency is low, and carbon pollution and insufficient structural stability exist in the molten salt environment. Utility Model Content

[0004] The purpose of this invention is to solve the problems of high temperature, high energy consumption, low graphitization degree and poor interfacial bonding in existing biomass carbon graphitization, and to provide a gradient pore foam nickel current collector integrated bamboo-based thin-layer graphite electrode, which realizes the integrated integration of low-temperature and high-efficiency graphitization and electrode structure.

[0005] This utility model is achieved through the following technical solution: A gradient-pore nickel foam current collector integrated with bamboo-based thin-film graphite electrode includes a current collector, a bamboo-based thin-film graphite active layer, a nickel foam skeleton, and a sleeve. The bamboo-based thin-film graphite active layer is disposed on the outer wall of the bottom of the current collector, the nickel foam skeleton is disposed on the outer wall of the bamboo-based thin-film graphite active layer, and the sleeve is connected and fitted onto the current collector, with both the bamboo-based thin-film graphite active layer and the nickel foam skeleton located inside the sleeve. The internal cavity of the sleeve is filled with molten electrolyte salt.

[0006] As a preferred technical solution, the nickel foam skeleton includes a circuit connection layer, an intermediate transition layer and an electrolyte contact anti-carbon layer arranged sequentially from the inside out, and a bamboo-based thin-layer graphite active layer is located between the circuit connection layer and the current collector.

[0007] As a preferred technical solution, the sleeve is made of dense yttrium-stabilized zirconium dioxide ceramic.

[0008] As a preferred technical solution, the thickness of the circuit connection layer, the thickness of the intermediate transition layer, and the thickness of the electrolyte contact anti-carbon layer are all ≤80µm.

[0009] As a preferred technical solution, the porosity of the circuit connection layer is ≥85%, and the pore size is 280-300μm; the porosity of the intermediate transition layer is >15% and <85%, and the pore size is 180-220μm; the porosity of the electrolyte contact carbon-resistant layer is ≤15%, and the pore size is 80-100μm.

[0010] Compared with the prior art, the beneficial effects of this utility model are as follows: 1) Low-temperature, high-efficiency graphitization: During operation, this electrode utilizes the electric field driven by molten salt electrolysis to induce ion directional migration and pore confinement effects, achieving high efficiency at temperatures ≤900°C. 0 High-efficiency graphitization of bamboo charcoal is achieved under C conditions, with a graphitization degree of up to 50-70%, reducing energy consumption by more than 60%, making it suitable for applications such as lithium battery anodes and supercapacitors.

[0011] 2) Gradient porosity synergistic effect: The electrode adopts a three-layer nickel foam skeleton structure, which optimizes electrolyte wetting, ion transport and electronic conduction paths, thereby improving the overall dynamic performance of the electrode.

[0012] 3) Integrated structural design: The thin-layer graphite active layer based on bamboo is tightly bonded to the current collector, which reduces interfacial impedance and enhances mechanical stability and cycle life.

[0013] 4) Oxygen ion conduction function: On the one hand, the bushing selectively conducts oxygen ions and blocks electrons during electrolysis. On the other hand, it acts as a physical barrier to prevent short circuit between the working electrode and the counter electrode.

[0014] 5) Green and sustainable: The electrode uses bamboo biomass as a carbon source, which is low-cost, environmentally friendly, and suitable for large-scale production. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the specific embodiments of this utility model, the accompanying drawings used in the specific embodiments will be briefly introduced below. In the drawings, the components or parts are not necessarily drawn to actual scale.

[0016] Figure 1 This is a schematic diagram of the structure of the electrode of this utility model.

[0017] In the figure: 1. Current collector; 2. Thin-layer graphite active layer based on bamboo; 3. Circuit connection layer; 4. Intermediate transition layer; 5. Electrolyte contact anti-carbon layer; 6. Sleeve; 7. Electrolyte molten salt; 8. Nickel foam skeleton. Detailed Implementation

[0018] The embodiments of the present utility model will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the present utility model and are not intended to limit its scope of protection. It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning understood by those skilled in the art to which this utility model pertains.

[0019] like Figure 1 As shown, this embodiment provides an integrated gradient porosity nickel foam current collector and bamboo-based thin-film graphite electrode, including a current collector 1, a bamboo-based thin-film graphite active layer 2, a nickel foam skeleton 8, and a sleeve 6. The bamboo-based thin-film graphite active layer 2 is disposed on the outer wall of the bottom of the current collector 1, the nickel foam skeleton 8 is disposed on the outer wall of the bamboo-based thin-film graphite active layer 2, and the sleeve 6 is fitted and connected to the current collector 1, with both the bamboo-based thin-film graphite active layer 2 and the nickel foam skeleton 8 located inside the sleeve 6. The internal cavity of the sleeve 6 is filled with an electrolyte molten salt 7.

[0020] The nickel foam skeleton 8 comprises, from the inside out, a circuit connection layer 3, an intermediate transition layer 4, and an electrolyte contact carbon-resistant layer 5, with a bamboo-based thin-layer graphite active layer 2 located between the circuit connection layer 3 and the current collector 1. The circuit connection layer 3 has a thickness ≤80µm, a porosity ≥85%, and a pore size of 280-300µm; it is used to inhibit carbon deposition and promote electrolyte diffusion. The intermediate transition layer 4 has a thickness ≤80µm, a porosity >15% and <85%, and a pore size of 180-220µm; it is used to balance ion transport and provide mechanical support. The electrolyte contact carbon-resistant layer 5 has a thickness ≤80µm, a porosity ≤15%, and a pore size of 80-100µm; it is used to effectively transfer electrons, enhance the conductivity of the current collector 1, and support the bamboo-based thin-layer graphite active layer 2. The bamboo-based thin-layer graphite active layer 2 is used for thin-layer graphite growth and enhances the interfacial bonding strength with the current collector 1.

[0021] The sleeve 6 is made of dense yttrium-stabilized zirconium dioxide ceramic. Its function is to selectively conduct oxygen ions and block electrons during electrolysis, and to act as a physical barrier to prevent short circuits between the working electrode and the counter electrode.

[0022] The gradient-pore nickel foam current collector integrated with bamboo-based thin-layer graphite electrode described in this embodiment achieves efficient graphitization of the bamboo carbonized derivative carbon precursor at low temperatures by designing a three-layer nickel foam framework 8 with gradient pore size. This is achieved in conjunction with the directional migration of ions and the pore confinement effect during the electrolysis process of the electrolyte molten salt 7. This results in a tightly bonded bamboo-based thin-layer graphite active layer 2 and current collector 1 structure, significantly improving the electrode's conductivity, mechanical stability, and electrochemical performance. The bamboo-based thin-layer graphite active layer 2 is formed in situ graphitized on the nickel foam framework 8 using bamboo carbonized derivative carbon as a precursor via molten salt electrochemistry, achieving a graphitization degree of 50-70%. The sleeve 6, made of dense yttrium-stabilized zirconium dioxide (YSZ) ceramic, serves as the oxygen ion conducting layer on the outermost layer of the electrode. This sleeve 6 has a dual function: firstly, it selectively conducts oxygen ions and blocks electrons during electrolysis; secondly, it acts as a physical barrier to prevent short circuits between the working electrode and the counter electrode. Ultimately, this can significantly improve graphitization efficiency and protect the internal current collector structure.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model, and they should all be covered within the scope of the claims and specification of this utility model.

Claims

1. A gradient-pore nickel foam current collector integrated with bamboo-based thin-film graphite electrode, characterized in that: It includes a current collector, a bamboo-based thin-layer graphite active layer, a nickel foam skeleton, and a sleeve. The bamboo-based thin-layer graphite active layer is disposed on the outer wall of the bottom of the current collector, the nickel foam skeleton is disposed on the outer wall of the bamboo-based thin-layer graphite active layer, and the sleeve is connected and fitted onto the current collector. Both the bamboo-based thin-layer graphite active layer and the nickel foam skeleton are located inside the sleeve, and the internal cavity of the sleeve is filled with electrolyte molten salt.

2. The gradient-pore nickel foam current collector integrated with bamboo-based thin-film graphite electrode according to claim 1, characterized in that: The nickel foam skeleton includes, from the inside out, a circuit connection layer, an intermediate transition layer, and an electrolyte contact anti-carbon layer, with a bamboo-based thin-layer graphite active layer located between the circuit connection layer and the current collector.

3. The gradient-pore nickel foam current collector integrated with bamboo-based thin-film graphite electrode according to claim 1 or 2, characterized in that: The sleeve is made of dense yttrium-stabilized zirconium dioxide ceramic.

4. The gradient-pore nickel foam current collector integrated with bamboo-based thin-film graphite electrode according to claim 2, characterized in that: The thickness of the circuit connection layer, the intermediate transition layer, and the electrolyte contact carbon-resistant layer are all ≤80µm.

5. The gradient-pore nickel foam current collector integrated with bamboo-based thin-film graphite electrode according to claim 2, characterized in that: The porosity of the circuit connection layer is ≥85%, and the pore size is 280-300μm; the porosity of the intermediate transition layer is >15% and <85%, and the pore size is 180-220μm. The porosity of the electrolyte contact layer is ≤15%, and the pore size is 80-100μm.

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