A flexible transparent battery based on alloy thin film electrodes

Abstract

The utility model discloses a kind of flexible transparent battery based on alloy thin film electrode, it is related to flexible energy storage device technical field, including substrate, alloy electrode layer, MXene-Si@C gel active layer, PEDOT:PSS buffer layer, solid electrolyte layer, core-shell structure, encapsulation layer from bottom to top are sequentially arranged;The alloy electrode layer is Ag-X alloy thin film, and thickness is 5-20nm;The MXene-Si@C gel active layer is the porous MXene-Si@C structure of 100-300nm thickness;Wherein, carbon shell thickness 10nm, particle size distribution: 50-100nm, dry film thickness is 100-300nm.The utility model alloy thin film component optimization: by doping trace Cu, Zn or Ti (1-10wt%), inhibit Ag oxidation and promote film adhesion, CuAg alloy oxidation resistance is improved 40%;Alloy-MXene interface bonding: doping metal (such as Ti) in alloy and MXene surface functional group (-O, -F) form Ti-O-Ti or Ti-F bond, reduce interface contact resistance.

Description

Technical Field

[0001] This utility model relates to the field of flexible energy storage device technology, specifically to a flexible transparent battery based on alloy thin film electrodes. Background Technology

[0002] Traditional flexible batteries are limited by the volume expansion effect of silicon anodes, resulting in short cycle life (<200 cycles). Transparent electrodes (such as ITO) have poor mechanical flexibility and are expensive; A single conductive network (such as carbon materials) cannot simultaneously achieve high transparency and high conductivity.

[0003] Pure silver films are easily oxidized to form Ag₂O, which leads to a decrease in conductivity; It is difficult to achieve both high light transmittance and mechanical flexibility in alloy films with high Ag content (>90%). The poor interfacial compatibility between the alloy film and MXene gel affects the charge transport efficiency.

[0004] Comparison of related technologies: CN113488658A: Discloses an MXene / silicon composite electrode, but does not solve the problems of transparency and interface stability; US20220109021A1: Uses silver nanowire transparent electrodes, but silver is easily oxidized and has poor compatibility with silicon.

[0005] CN114597241A: Discloses a transparent Ag nanowire electrode, but does not solve the Ag oxidation problem. Therefore, a flexible transparent battery suitable for wearable devices, foldable screen phones, and other applications requiring high flexibility and optical performance is designed. Utility Model Content

[0006] The purpose of this invention is to provide a flexible transparent battery based on alloy thin film electrodes, thereby solving the above-mentioned technical problems.

[0007] The objective of this utility model can be achieved through the following technical solutions: A flexible transparent battery based on alloy thin film electrodes includes, from bottom to top, a substrate, an alloy electrode layer, an MXene-Si@C gel active layer, a PEDOT:PSS buffer layer, a solid electrolyte layer, a core-shell structure, and an encapsulation layer; The substrate can be any one of the following materials: polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polydimethylsiloxane (PDMS). The alloy electrode layer is an Ag-X alloy thin film, where X = Cu / Zn / Ti, Ag accounts for 90-99 wt%, and the thickness is 5-20 nm; the mass percentage of the Ag:X thin film is 99%-90%:1%-10%. The MXene-Si@C gel active layer is a porous MXene-Si@C structure with a thickness of 100-300 nm; wherein, the carbon shell thickness is 10 nm, the particle size distribution is 50-100 nm, and the dry film thickness is 100-300 nm.

[0008] As a further aspect of this invention, the thickness of the PEDOT:PSS buffer layer is 150-400nm.

[0009] As a further embodiment of this invention: the solid electrolyte layer is a 10-60μm PEO-based polymer solid electrolyte with inorganic fillers (such as TiO2, ZnO, In2O3, Al2O3 and Ga2O3).

[0010] As a further embodiment of this invention: the core-shell structure is LiFePO4@MXene, the diameter of the LiFePO4 core is 30-500nm; the thickness of the MXene shell is 1-60nm, and the dry film thickness is 80-600nm.

[0011] As a further embodiment of this invention: the encapsulation layer is a PET / Al composite film with a thickness of 50±5μm.

[0012] As a further aspect of this invention: the gradient alloy electrode layer and the MXene layer in the MXene-Si@C gel active layer form an interpenetrating structure.

[0013] The beneficial effects of this utility model are: 1. Alloy film composition optimization: By doping with trace amounts of Cu, Zn, or Ti (1-10 wt%), Ag oxidation is suppressed and film adhesion is improved, resulting in a 40% increase in the oxidation resistance of CuAg alloys; 2. Alloy-MXene interface bonding: The doped metal (such as Ti) in the alloy forms Ti-O-Ti or Ti-F bonds with the functional groups (-O, -F) on the MXene surface, reducing the interfacial contact resistance; 3. Alloy Thin Film-MXene Hybrid Conductive Network: An ultrathin silver film is deposited on the substrate by magnetron sputtering and forms an interpenetrating structure with the MXene gel layer, achieving high transmittance (>75% at 550nm wavelength) and low surface resistivity (<9Ω / sq). 4. Biomimetic pomegranate structure encapsulation: Microcavity encapsulation of Si@C particles is constructed in MXene gel, and an alloy film serves as an external conductive framework to suppress volume expansion; 5. Gradient Porosity Design: The electrode transitions from a dense alloy layer on the substrate side to a porous MXene-Si@C active layer, balancing ion / electron transport with active material loading (>2mAh / cm³). 2 ); 6. The core-shell structure (LiFePO4@MXene) combines the high safety and stability of lithium iron phosphate (LiFePO4) with that of MXene (such as Ti3C2T). X High conductivity and adjustable structure; 7. Core-shell structures (LiFePO4@MXene) exist in lithium-ion batteries as nano- to micron-sized composite particles, with lithium iron phosphate (LiFePO4) at the core and uniformly coated with MXene sheets on the outside. This structure significantly improves electrode performance through a synergistic effect of physical and chemical processes. This invention improves conversion efficiency and stability, and has high practical value and broad application prospects. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings.

[0015] Figure 1 This is a schematic diagram of the structure of this application; Figure 2 This is the transmittance spectrum of the composite electrode in Embodiment 1 of this application; Figure 3 This is the transmittance spectrum of the composite electrode in Embodiment 2 of this application. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0017] Please see Figure 1 As shown, this utility model is a flexible transparent battery based on alloy thin film electrodes, including a substrate 1, an alloy electrode layer 2, an MXene-Si@C gel active layer 3, a PEDOT:PSS buffer layer 4, a solid electrolyte layer 5, a core-shell structure 6 (positive electrode layer), and an encapsulation layer 7 arranged sequentially from bottom to top.

[0018] An Ag-based alloy thin film (target material is Ag-X alloy, X=Cu / Zn / Ti) is deposited on substrate 1 by magnetron sputtering to form alloy electrode layer 2; MXene colloid and Si@C powder were added to 3-aminopropyltriethoxysilane and ethanol / deionized water at a mass ratio of 3:1 to obtain MXene-Si@C gel, which was then coated on the surface of alloy electrode layer 2 and dried to form MXene-Si@C gel active layer 3. The flexible substrate was impregnated in the diluted PEDOT:PSS solution and dried to obtain PEDOT:PSS buffer layer 4. PEO and LiTFSI were mixed in a molar ratio of 15:1 and added to acetonitrile to obtain an electrolyte, which was then coated on the surface of PEDOT:PSS buffer layer 4 and dried to form a solid electrolyte layer 5. Ti3C2T x The dispersion was added to the LiFePO4 precursor solution and mixed. The resulting dispersion was subjected to hydrothermal reaction, cooling and centrifugation, washing, drying and annealing to obtain the positive electrode layer. A flexible battery is obtained by hot-pressing a PET / Al composite film to encapsulate the positive electrode and a flexible substrate containing a solid electrolyte layer to form an encapsulation layer 7.

[0019] Example 1: like Figure 2 As shown, a flexible transparent battery based on an alloy thin-film electrode includes polyimide (PI) as a flexible substrate 1.

[0020] The alloy electrode layer is an Ag-Cu alloy thin film with a thickness of 10 nanometers; the mass percentage of the Ag:X thin film is 96%:4%. The MXene-Si@C gel active layer is a porous MXene-Si@C structure with a thickness of 200 nm; wherein, the carbon shell has a thickness of 10 nm and a particle size distribution of 60 nm. The PEDOT:PSS buffer layer has a thickness of 200nm; The solid electrolyte layer is a 20μm PEO-based polymer solid electrolyte with 1% In2O3 filler. The cathode layer has a core-shell structure (LiFePO4@MXene), with a core (LiFePO4) diameter of 200 nm and a shell (MXene) thickness of 10 nm, resulting in a dry film thickness of 300 nm. The encapsulation layer is a PET / Al composite film with a thickness of 48μm.

[0021] Performance testing of the obtained flexible transparent battery: Light transmittance: 75.2% (380nm-760nm wavelength); Surface resistivity: 9Ω / sq; Ionic conductivity: 1.5×10 -4 S / cm; Antioxidant properties (85% humidity, 72 hours): Resistance increased by only 7% (pure Ag film increased by 25%). Electrochemical performance: Areometric capacity: 2.3 mAh / cm³ 2 (0.1C, voltage window 0.01-1.5V vs. Li / Li+). Cyclic stability: 84% capacity retention after 1000 cycles (1C charge / discharge); Bending test: Capacity decay <3% after 2000 cycles (1mm radius); Scratch adhesion: Critical load 15N (ASTM C1624 standard).

[0022] Example 2: like Figure 3 As shown, a flexible transparent battery based on an alloy thin-film electrode includes a polyethylene terephthalate (PET) substrate 1.

[0023] The alloy electrode layer is an Ag-Ti alloy thin film with a thickness of 8 nm; the mass percentage of the Ag:X thin film is 98.5%:1.5%. The MXene-Si@C gel active layer is a porous MXene-Si@C structure with a thickness of 100 nm; wherein, the carbon shell has a thickness of 10 nm and a particle size distribution of 50 nm. The PEDOT:PSS buffer layer has a thickness of 150nm; The solid electrolyte layer is a 20μm PEO-based polymer solid electrolyte with 0.5% d Ga2O3 filler. The cathode layer has a core-shell structure (LiFePO4@MXene), with a core (LiFePO4) diameter of 300 nm and a shell (MXene) thickness of 30 nm, resulting in a dry film thickness of 450 nm. The encapsulation layer is a PET / Al composite film with a thickness of 50μm.

[0024] Performance testing of the obtained flexible transparent battery: Light transmittance: 75.64%, surface resistivity: 9.3 Ω / sq; ionic conductivity: 1.6 × 10⁻⁶ -4 S / cm; Antioxidant properties (85% humidity, 72 hours): Resistance increased by only 6% (pure Ag film increased by 25%). Electrochemical performance: Areometric capacity: 2.4 mAh / cm³ 2 (0.1C, voltage window 0.01-1.5V vs. Li / Li) + ); Cyclic stability: 86% capacity retention after 1000 cycles (1C charge / discharge); Bending test: Capacity decay <3% after 2000 cycles (1mm radius); Interfacial bonding strength (scratch test): critical load 18N (better than CuAg's 15N, pure Ag film is 9N).

[0025] The above description provides a detailed account of one embodiment of the present invention. However, this description is merely a preferred embodiment and should not be construed as limiting the scope of the present invention. All equivalent variations and improvements made within the scope of the claims of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A flexible transparent battery based on an alloy thin-film electrode, characterized in that, The structure consists of, from bottom to top, a substrate (1), an alloy electrode layer (2), an MXene-Si@C gel active layer (3), a PEDOT:PSS buffer layer (4), a solid electrolyte layer (5), a core-shell structure (6), and an encapsulation layer (7). The alloy electrode layer (2) is an Ag-X alloy thin film with a thickness of 5-20 nm; The MXene-Si@C gel active layer (3) is a porous MXene-Si@C structure with a thickness of 100-300 nm; wherein, the carbon shell thickness is 10 nm, the particle size distribution is 50-100 nm, and the dry film thickness is 100-300 nm.

2. A flexible transparent battery based on an alloy thin-film electrode according to claim 1, characterized in that, The thickness of the PEDOT:PSS buffer layer (4) is 150-400 nm.

3. A flexible transparent battery based on an alloy thin-film electrode according to claim 1, characterized in that, The core-shell structure (6) is LiFePO4@MXene, with the LiFePO4 core having a diameter of 30-500nm; the MXene shell having a thickness of 1-60nm; and the dry film having a thickness of 80-600nm.

4. A flexible transparent battery based on an alloy thin-film electrode according to claim 1, characterized in that, The encapsulation layer (7) is a PET / Al composite film with a thickness of 50±5μm.

5. A flexible transparent battery based on an alloy thin-film electrode according to claim 1, characterized in that, The alloy electrode layer (2) and the MXene layer in the MXene-Si@C gel active layer (3) form an interpenetrating structure.

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