Filamentous fungus biomass membrane, quasi-solid electrolyte and preparation method and application of filamentous fungus biomass membrane and quasi-solid electrolyte

Abstract

The invention belongs to the technical field of lithium / sodium batteries, and particularly relates to a filamentous fungus biomass membrane, a quasi-solid electrolyte and a preparation method and application of the filamentous fungus biomass membrane and the quasi-solid electrolyte. The preparation method of the filamentous fungus biomass membrane provided by the invention comprises the following steps: performing first-stage culture on filamentous fungus spores to obtain filamentous fungi; the filamentous fungi are soaked in a treatment solution for second-stage culture, and treated filamentous fungi are obtained; the treated filamentous fungi are subjected to cold pressing, and the filamentous fungus biomass film is obtained; the treatment solution is a transition metal salt solution or deionized water. The mycelia of the prepared filamentous fungus biomass membrane present a one-dimensional structure, the cell wall of the one-dimensional structure presents the unique characteristic of natural interweaving of a crystalline region and an amorphous region, the prepared quasi-solid electrolyte has high conductivity, and when the quasi-solid electrolyte is applied to a lithium / sodium metal battery, the comprehensive performance of the battery can be improved, and the service life of the battery is prolonged. And excellent capacity retention ratio and rate capability are shown.

Description

Technical Field

[0001] This invention belongs to the field of lithium / sodium battery technology, specifically relating to a filamentous fungal biomass membrane and a quasi-solid-state electrolyte, as well as their preparation methods and applications. Background Technology

[0002] Energy storage devices, as a key technological bridge connecting clean energy and end-user electricity, are of great research significance. Currently, the representative commercial rechargeable battery is the liquid lithium-ion battery. However, it has two significant drawbacks: first, the graphite anode has reached near its theoretical capacity, making it difficult to meet the demands of high-energy-density applications as the market expands; second, liquid batteries typically use organic solvents as electrolyte components, which are volatile and flammable, posing safety hazards during use and failing to suppress lithium dendrite formation, often leading to short-circuit failure. To address these issues, quasi-solid-state and all-solid-state lithium metal batteries have been developed in this field. Furthermore, sodium batteries, with their abundant sodium resources and wider temperature range, are also being explored as a novel energy storage system.

[0003] Polymer solid-state electrolytes exhibit good mechanical flexibility, effectively suppressing lithium dendrite growth and possessing superior electrode interface compatibility. However, conventional polymer solid-state electrolytes typically incorporate lithium or sodium salts into the polymer matrix, utilizing highly polar functional groups to promote salt dissociation and relying primarily on the movement of polymer chain segments within amorphous regions for ion transport. Such electrolytes often suffer from insufficient ionic conductivity at room temperature due to high crystallinity, thus limiting overall battery performance. Biomass materials offer advantages such as wide availability, renewability, environmental friendliness, unique natural structures, and tunable physicochemical structures. Rich in polar groups, biomass materials can facilitate rapid lithium-ion transport through ion interactions or weak coordination, inducing uniform lithium deposition. Furthermore, fibrous biomass materials possess a natural one-dimensional structure, providing abundant physical transport pathways for lithium ions. Therefore, fibrous biomass materials hold immense potential in electrolyte applications.

[0004] Related technologies disclose the preparation of biomass cellulose-based polymer solid electrolytes by combining nanocellulose with a polymer matrix and achieving bonding, polymer chain segment shearing, and cross-linking through gamma irradiation. Another related technology discloses the preparation of bio-based polymer solid electrolyte membranes by combining biomass binders such as lignin and sericin with lithium salts. However, the biomass solid electrolytes prepared by the above-mentioned technologies usually involve using biomass through multiple complex chemical processing steps to obtain a single component (such as cellulose or lignin) as the biomass electrolyte. In the process of chemical processing, the inherent natural structure of biomass is often destroyed, failing to fully utilize its natural ordered structural advantages, thus resulting in low conductivity. Summary of the Invention

[0005] The purpose of this invention is to provide a filamentous fungal biomass membrane and a quasi-solid electrolyte, as well as their preparation method and application. The filamentous fungal biomass membrane prepared by this invention utilizes the fibrous structure of filamentous fungi and the cell wall structure composed of interwoven crystalline chitin and amorphous dextran to provide a continuous and stable transport path for ion migration, thereby improving the conductivity of the prepared quasi-solid electrolyte.

[0006] To achieve the objectives of this invention, the following technical solutions are provided: A method for preparing a filamentous fungal biofilm includes the following steps: Filamentous fungal spores were cultured in the first stage to obtain filamentous fungi; The filamentous fungi were immersed in a treatment solution for a second stage of culture to obtain the treated filamentous fungi; The treated filamentous fungi are cold-pressed to obtain the filamentous fungal biofilm; The treatment solution is a transition metal salt solution or deionized water.

[0007] Preferably, the filamentous fungi include Aspergillus niger, Aspergillus oryzae, Trichoderma reesei, or Penicillium chrysogenum.

[0008] Preferably, the first stage of culture is carried out in a culture medium, which includes a sugar source, a nitrogen source and water, and the mass ratio of the sugar source, nitrogen source and water is 2~3:1.5~2:100; the temperature of the first stage of culture is 25~40℃ and the time is 16~72h.

[0009] Preferably, the transition metal salt in the transition metal salt solution includes copper salt, iron salt, manganese salt, or zinc salt; the concentration of the transition metal salt solution is 0.01~0.06 mol / L; the temperature of the second stage of cultivation is 25~40℃, and the time is 24~48h.

[0010] Preferably, the hyphae of the filamentous fungi being treated have a diameter of 1.5~2μm; and the pressure of the cold pressing is 1~6MPa.

[0011] The present invention provides that the filamentous fungal biofilm prepared by the preparation method described above is a transition metal hybrid biofilm or a non-hybrid biofilm.

[0012] This invention provides the application of the filamentous fungal biofilm described in the above technical solution in quasi-solid electrolytes.

[0013] A quasi-solid-state electrolyte based on filamentous fungal biomass includes a filamentous fungal biomass membrane and an electrolyte solution permeating the filamentous fungal biomass membrane; the filamentous fungal biomass membrane is the filamentous fungal biomass membrane described in the above technical solution; the electrolyte solution is a lithium battery electrolyte or a sodium battery electrolyte.

[0014] Preferably, the thickness of the filamentous fungal biomass quasi-solid electrolyte is 0.3~0.8 mm, and the lithium content in the filamentous fungal biomass quasi-solid electrolyte is 5.041~5.058 ppm, and the sodium content is 4.992~5.012 ppm.

[0015] This invention provides the application of the filamentous fungal biomass quasi-solid electrolyte described in the above technical solution in lithium metal batteries or sodium metal batteries.

[0016] This invention provides a method for preparing a filamentous fungal biofilm, comprising the following steps: culturing filamentous fungal spores in a first stage to obtain filamentous fungi; immersing the filamentous fungi in a treatment solution for a second stage of cultivation to obtain treated filamentous fungi; and cold-pressing the treated filamentous fungi to obtain the filamentous fungal biofilm; wherein the treatment solution is a transition metal salt solution or deionized water. This invention utilizes filamentous fungi, widely distributed in nature, as a biomass matrix. The natural structure of their cell walls is mainly composed of interwoven crystalline chitin and amorphous dextran. The crystalline regions impart effective mechanical strength to the material, while the amorphous regions facilitate ion transport. Simultaneously, the fibrous structure of filamentous fungi provides a continuous and stable transport path for ion migration.

[0017] Furthermore, this invention utilizes the bioadsorption properties of filamentous fungi to achieve chemical modification through the adsorption of transition metal ions. The transition metal ions coordinate with functional groups (-OH, -COOH, or -CONH-) and undergo electrostatic adsorption. By adjusting the charge, "competitive adsorption" is generated, which effectively reduces the strong adsorption of lithium and sodium ions by polar functional groups and improves the transport kinetics of transition metal ions.

[0018] This invention prepares a quasi-solid electrolyte by adsorbing an electrolyte solution onto a filamentous fungal biomass membrane, which exhibits excellent mechanical properties and high ionic conductivity. Applying this quasi-solid electrolyte from filamentous fungal biomass to lithium / sodium metal batteries significantly improves the overall battery performance, resulting in batteries with excellent capacity retention and rate performance. Attached Figure Description Figure 1 This is a photograph of the unhybridized biofilm prepared from 50 mg of unhybridized mycelium in Example 1 of the present invention. Figure 2 This is a scanning electron microscope (SEM) image of the unhybridized biomass membrane prepared from 50 mg of unhybridized mycelium in Example 1 of the present invention; Figure 3 The images show the SEM images and elemental distribution diagrams of the unhybridized fungal mycelial balls in Example 1 of this invention. Figure 4The images show the SEM images and elemental distribution diagrams of the copper-ion hybrid fungal hyphae in Example 2 of this invention. Figure 5 Thermogravimetric curves of the unhybridized biomass membrane in Example 1 and the copper ion hybridized biomass membrane in Example 2 are shown. Figure 6 The lithium-ion or sodium-ion conductivity of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolytes of Examples 2-6 are compared. Figure 7 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 2 in lithium batteries. Figure 8 The graph shows the rate performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 2 in a sodium battery. Figure 9 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 3 in lithium batteries. Figure 10 The graph shows the rate performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 3 in a sodium battery. Figure 11 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 4 in lithium batteries. Figure 12 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 4 in a sodium battery. Figure 13 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 2 in lithium batteries. Figure 14 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 2 in a sodium battery. Figure 15 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 5 in lithium batteries. Figure 16 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 5 in a sodium battery. Figure 17 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 6 in lithium batteries. Figure 18 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 6 in a sodium battery. Detailed Implementation

[0019] This invention provides a method for preparing filamentous fungal biofilm, comprising the following steps: Filamentous fungal spores were cultured in the first stage to obtain filamentous fungi; The filamentous fungi were immersed in a treatment solution for a second stage of culture to obtain the treated filamentous fungi; The treated filamentous fungi are cold-pressed to obtain the filamentous fungal biofilm; The treatment solution is a transition metal salt solution or deionized water.

[0020] In this invention, unless otherwise specified, all raw materials used in the preparation are preferably commercially available products well known to those skilled in the art.

[0021] This invention involves a first-stage culture of filamentous fungal spores to obtain filamentous fungi. In one embodiment of this invention, the filamentous fungi include *Aspergillus niger*, *Aspergillus oryzae*, *Trichoderma reesei*, or *Penicillium chrysogenum*; preferably, filamentous fungi with high safety profiles are preferred. This invention utilizes filamentous fungi, widely distributed in nature, as a biomass matrix. The natural structure of their cell walls is primarily composed of an interweaving of crystalline chitin and amorphous dextran. The crystalline regions impart effective mechanical strength to the material, while the amorphous regions facilitate ion transport. Furthermore, the fibrous structure of filamentous fungi provides a continuous and stable transport pathway for ion migration.

[0022] In one embodiment of the present invention, the first stage of cultivation is carried out in a culture medium comprising a sugar source, a nitrogen source, and water. The mass ratio of the sugar source, nitrogen source, and water can be 2-3:1.5-2:100, specifically 2:1.6:100. The sugar source includes one or more of glucose, sucrose, maltose, corn starch, and potato starch. The nitrogen source includes one or more of peptone, yeast extract, and beef extract. The water is deionized water. The present invention regulates the microbial growth rate by limiting the ratio of sugar source, nitrogen source, and water in the culture medium.

[0023] In one embodiment of the present invention, the culture medium is preferably subjected to autoclaving followed by a first-stage culture. The autoclaving temperature can be 121°C, the time can be 15 min, and the pressure can be 103.4 kPa. The first-stage culture is carried out under constant temperature and shaking conditions. The temperature of the first-stage culture can be 25~40°C, specifically 36°C, and the time can be 16~72 h, specifically 40 h. The shaking rate can be 150~250 rpm, specifically 200 rpm. The present invention aims to obtain filamentous fungi in the mycelial stage. After the first-stage culture time exceeds 24 h, the morphology of the fungi is observed regularly to ensure that the obtained filamentous fungi are in a relatively complete mycelial stage and have not differentiated into propagules.

[0024] After obtaining the filamentous fungi, the present invention immerses the filamentous fungi in a treatment solution for a second-stage culture to obtain treated filamentous fungi; the treatment solution is a transition metal salt solution or deionized water. As one embodiment of the present invention, when the treatment solution is deionized water, the obtained treated filamentous fungi are non-hybridized filamentous fungi; when the treatment solution is a transition metal salt solution, the obtained treated filamentous fungi are transition metal hybridized filamentous fungi.

[0025] In one embodiment of the present invention, when the treatment solution is a transition metal salt solution, the transition metal salt in the transition metal salt solution includes copper salt, iron salt, manganese salt or zinc salt; the concentration of the transition metal salt solution can be 0.01~0.06 mol / L, further can be 0.02~0.06 mol / L, specifically 0.02 mol / L, 0.04 mol / L or 0.06 mol / L.

[0026] This invention utilizes the bioadsorption properties of filamentous fungi to achieve chemical modification through the adsorption of transition metal ions. Transition metal ions coordinate with functional groups (-OH, -COOH, or -CONH-) and undergo electrostatic adsorption. By regulating charge, "competitive adsorption" is generated, effectively reducing the strong adsorption of lithium and sodium ions by polar functional groups and improving the transport kinetics of transition metal ions. This invention can control the hybridization of transition metals on the surface of filamentous fungi by limiting the concentration of the transition metal salt solution, which is beneficial to the ion conduction of transition metal hybrid fungi. As the concentration of transition metal ions gradually increases from low to high, some crystallization peaks of chitin first weaken and then strengthen. When the concentration of transition metal ions exceeds the concentration limited by this invention, excessively high concentrations will enhance crystallinity. Amorphous regions, on the other hand, are conducive to promoting ion transport; therefore, excessively high transition metal ion concentrations are detrimental to ionic conductivity.

[0027] In one embodiment of the present invention, before the second stage of cultivation, the filamentous fungi are preferably washed using deionized water as the washing solvent. The second stage of cultivation is carried out under constant temperature and shaking conditions. The temperature of the second stage of cultivation can be 25-40℃, specifically 36℃, and the time can be 24-48h, specifically 36h. The shaking rate can be 150-250rpm, specifically 200rpm. In another embodiment of the present invention, after the second stage of cultivation, the product is further subjected to washing, freeze-drying, and vacuum drying in sequence to obtain the treated filamentous fungi. The washing method is not particularly limited and can be a conventional method of the present invention. The freeze-drying temperature is -30 to -35℃, and the time can be 2 days. The vacuum drying temperature is 60-80℃, specifically 60℃, 70℃, or 80℃, and the time can be 6-10h, specifically 8h. The hyphae diameter of the treated filamentous fungi is 1.5-2μm.

[0028] After obtaining the treated filamentous fungi, the present invention cold-presses the treated filamentous fungi to obtain the filamentous fungal biomass membrane. In one embodiment of the present invention, the cold pressing includes spreading the treated filamentous fungi flat in a mold; the pressure of the cold pressing can be 1~6 MPa, specifically 2~3 MPa, and the cold pressing time can be 15~25 s, specifically 20 s. The present invention uses cold pressing to shape and densify the treated filamentous fungi through mechanical external force without heating, while simultaneously improving interfacial strength.

[0029] This invention provides a filamentous fungal biomass membrane prepared by the preparation method described in the above technical solution. As one embodiment of this invention, the filamentous fungal biomass membrane is a transition metal hybrid biomass membrane or a non-hybridized biomass membrane; the content of transition metal ions in the transition metal hybrid biomass membrane is 0~43.26 ppm. The thickness of the transition metal hybrid biomass membrane prepared from 50 mg of transition metal hybrid fungal hyphae is 0.3~0.4 mm, and the thickness of the transition metal hybrid biomass membrane prepared from 100 mg of transition metal hybrid fungal hyphae is 0.5~0.7 mm.

[0030] This invention provides the application of the filamentous fungal biofilm described in the above technical solution in quasi-solid electrolytes.

[0031] This invention provides a quasi-solid electrolyte based on filamentous fungal biomass, comprising a filamentous fungal biomass membrane and an electrolyte solution permeating the filamentous fungal biomass membrane; the filamentous fungal biomass membrane is the filamentous fungal biomass membrane described in the above technical solution; the filamentous fungal biomass quasi-solid electrolyte is a transition metal hybrid biomass quasi-solid electrolyte or a non-hybridized biomass quasi-solid electrolyte.

[0032] As one embodiment of the present invention, the preparation method of the quasi-solid electrolyte from filamentous fungal biomass includes the following steps: The filamentous fungal biomass membrane was immersed in an electrolyte solution to obtain the filamentous fungal biomass quasi-solid electrolyte.

[0033] In one embodiment of the present invention, the electrolyte solution is a lithium battery electrolyte or a sodium battery electrolyte; the lithium battery electrolyte is a commonly used lithium battery electrolyte in the art, specifically including lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) (1,3-dioxopentane (DOL): 1,2-dimethoxyethane (DME) = 1:1 vol%), with a concentration of 1M; the sodium battery electrolyte is a commonly used sodium battery electrolyte in the art, specifically including sodium perchlorate (NaClO4) (diethyl carbonate (DEC): ethylene carbonate (EC) = 1:1 vol%), with a concentration of 1M; the soaking time is 1-2 days. The present invention involves immersing a filamentous fungal biomass membrane in an electrolyte solution to introduce lithium or sodium salts into the filamentous fungal biomass membrane.

[0034] In one embodiment of the present invention, the thickness of the transition metal hybrid biomass quasi-solid electrolyte is 0.3~0.8 mm, specifically 0.4~0.75 mm; the lithium content in the transition metal hybrid biomass quasi-solid electrolyte is 5.041~5.058 ppm, and the sodium content is 4.992~5.012 ppm. The lithium-ion conductivity of the transition metal hybrid biomass quasi-solid electrolyte is 1.26 × 10⁻⁶. -3 ~1.7×10 -3 S / cm, sodium ion conductivity 1.08×10 -3 ~1.22×10 -3 S / cm.

[0035] This invention provides the application of the filamentous fungal biomass quasi-solid-state electrolyte described in the above-mentioned technical solution in lithium metal batteries or sodium metal batteries. As one embodiment of this invention, the positive electrode material of the lithium metal battery is lithium iron phosphate, and the negative electrode material is lithium metal; the positive electrode material of the sodium metal battery is sodium vanadium phosphate, and the negative electrode material is sodium metal. This invention applies the filamentous fungal biomass quasi-solid-state electrolyte to lithium / sodium metal batteries, which can significantly improve the overall battery performance, and the assembled battery exhibits excellent capacity retention and rate performance.

[0036] To further illustrate the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments thereof. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0037] Example 1 S1: Prepare a liquid culture medium by mixing glucose, peptone and deionized water at a mass ratio of 2:1.6:100. Sterilize the liquid culture medium at 121℃ for 15 min under a pressure of 103.4 kPa. Inoculate the liquid culture medium with Aspergillus niger spores (purchased from Hangzhou Baocang Biotechnology Co., Ltd., second generation Aspergillus brasiliensis CMCC(F)98003 standard strain) and culture at 36℃ with constant temperature shaking for 40 h to obtain uniformly dispersed, fluffy fungal mycelial balls.

[0038] S2: The fungal mycelial balls are washed with deionized water, soaked in deionized water and cultured at 36°C for 36 hours; the cultured fungal mycelial balls are freeze-dried at -35°C for 2 days, and the freeze-dried fungal mycelial balls are vacuum-dried at 80°C for 8 hours to obtain unhybridized fungal mycelial balls.

[0039] S3: Take 50mg and 100mg of the unhybridized fungal mycelial balls respectively and put them into the mold, spread them evenly, apply a pressure of 2MPa and hold for 20s to obtain an unhybridized biofilm.

[0040] S4: Immerse the unhybridized biomass membrane in 1M LiTFSI (DOL:DME=1:1vol%) lithium battery electrolyte or 1M NaClO4 (DEC:EC=1:1vol%) sodium battery electrolyte for 1 day at room temperature; remove the immersed unhybridized biomass membrane, wipe off the surface electrolyte solution, and obtain unhybridized biomass quasi-solid electrolyte.

[0041] The average thickness of the unhybridized biomass quasi-solid electrolyte obtained from 50 mg of unhybridized fungal mycelial balls was 0.40 mm. The unhybridized biomass quasi-solid electrolyte was used as the electrolyte in battery assembly for button battery performance testing. The average thickness of the unhybridized biomass quasi-solid electrolyte obtained from 100 mg of unhybridized fungal mycelial balls was 0.75 mm, and it was used for ionic conductivity determination.

[0042] Figure 1 This is a photograph of the unhybridized biofilm prepared from 50 mg of unhybridized mycelium in Example 1 of the present invention. Figure 2This is a scanning electron microscope (SEM) image of the unhybridized biomass membrane prepared from 50 mg of unhybridized mycelium in Example 1 of the present invention; Figure 3 The images show the SEM image and elemental distribution diagram of the unhybridized fungal mycelial balls in Example 1 of this invention.

[0043] according to Figure 1 and Figure 2 It can be seen that the unhybridized biomass membrane prepared by the cold pressing process has good formability, continuous and complete structure, and uniform surface texture; through Figure 3 It can be seen that the diameter of the hyphae of the non-hybridized fungi ranges from 1.5 to 2 μm; nitrogen and oxygen elements are evenly distributed on the hyphae of the non-hybridized fungi, and no copper element was observed.

[0044] Example 2 S1: Prepare a liquid culture medium by mixing glucose, peptone and deionized water at a mass ratio of 2:1.6:100. Sterilize the liquid culture medium at 121°C for 15 min under a pressure of 103.4 kPa. Inoculate the liquid culture medium with Aspergillus niger spores and culture at 36°C with constant temperature shaking for 40 h to obtain uniformly dispersed, fluffy fungal mycelial balls.

[0045] S2: Copper acetate was mixed with deionized water to obtain a copper acetate solution with a concentration of 0.02 mol / L; the fungal mycelial balls were washed with deionized water, soaked in the copper acetate solution, and cultured at 36°C with constant temperature shaking for 36 h; the cultured fungal mycelial balls were washed with deionized water, freeze-dried at -35°C for 2 days, and the freeze-dried fungal mycelial balls were vacuum dried at 80°C for 8 h to obtain copper ion hybrid fungal mycelial balls; S3: Take 50mg and 100mg of the copper ion hybrid fungal mycelial balls respectively and put them into the mold, spread them evenly, apply a pressure of 2MPa and keep it for 20s to obtain a copper ion hybrid biomass membrane.

[0046] S4: Immerse the copper ion hybrid biomass membrane in 1M LiTFSI (DOL:DME=1:1vol%) lithium battery electrolyte or 1M NaClO4 (DEC:EC=1:1vol%) sodium battery electrolyte for 1 day at room temperature; remove the immersed copper ion hybrid biomass membrane, wipe off the electrolyte solution on the surface, and obtain copper ion hybrid biomass quasi-solid electrolyte.

[0047] The average thickness of the copper ion hybrid biomass quasi-solid electrolyte obtained from 50 mg of copper ion hybrid fungal mycelial balls was 0.40 mm. The copper ion hybrid biomass quasi-solid electrolyte was used as the electrolyte for battery assembly and for button battery performance testing. The average thickness of the copper ion hybrid biomass quasi-solid electrolyte obtained from 100 mg of copper ion hybrid fungal mycelial balls was 0.75 mm, and it was used for ionic conductivity determination.

[0048] Figure 4 The images show the SEM images and elemental distribution diagrams of the copper-ion hybrid fungal hyphae in Example 2 of this invention. Figure 5 The thermogravimetric curves are shown for the unhybridized biomass membrane in Example 1 and the copper ion hybridized biomass membrane in Example 2 of the present invention.

[0049] according to Figure 4 It can be seen that the diameter of the copper-ion hybrid fungal hyphae is in the range of 1.5~2μm, and the copper element is uniformly distributed on the copper-ion hybrid fungal hyphae. According to... Figure 5 It can be seen that the degradation temperature of the unhybridized biomass membrane prepared in Example 1 is 230℃, which shows good heating stability; the degradation temperature of the copper ion hybridized biomass membrane prepared in Example 2 is 220℃, which also shows good heating stability.

[0050] Example 3 S1 is the same as in Example 2; S2 is basically the same as Example 2, except that a copper acetate solution with a concentration of 0.04 mol / L is obtained; S3~S4 are the same as in Example 2.

[0051] Example 4 S1 is the same as in Example 2; S2 is basically the same as Example 2, except that a copper acetate solution with a concentration of 0.06 mol / L is obtained; S3~S4 are the same as in Example 2.

[0052] Example 5 S1 is the same as in Example 2; S2 is basically the same as Example 2, except that copper nitrate is mixed with deionized water to obtain a copper nitrate solution with a concentration of 0.02 mol / L. S3~S4 are the same as in Example 2.

[0053] Example 6 S1 is the same as in Example 2; S2 is basically the same as Example 2, except that ferric acetylacetone is mixed with deionized water to obtain a ferric acetylacetone solution with a concentration of 0.06 mol / L. S3~S4 are the same as in Example 2.

[0054] Test Example 1 The lithium content of the unhybridized biomass quasi-solid electrolyte described in Example 1 was 5.041~5.058 ppm and the sodium content was 4.992~5.012 ppm, as detected by inductively coupled plasma atomic emission spectrometry (ICP). The lithium content of the transition metal hybridized biomass quasi-solid electrolytes prepared in Examples 2~6 was 5.041~5.058 ppm and the sodium content was 4.992~5.012 ppm.

[0055] The electrochemical performance of the unhybridized biomass quasi-solid electrolyte prepared in Example 1 and the transition metal hybridized biomass quasi-solid electrolytes prepared in Examples 2-6 were tested, and the results are as follows: Figure 6 As shown.

[0056] Figure 6 The lithium-ion or sodium-ion conductivity of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolytes of Examples 2-6 are compared. Figure 6 In the figure (a), the lithium-ion conductivity is... Figure 6 In the middle (b), the conductivity of sodium ions is represented.

[0057] according to Figure 6 It can be seen that, at room temperature (25°C), the lithium-ion conductivity of the unhybridized biomass quasi-solid electrolyte in Example 1 is 1.16 × 10⁻⁶. -3 S / cm, sodium ion conductivity is 1.01×10 -3 S / cm; The lithium-ion conductivity of the 0.02M copper ion (copper acetate) hybrid biomass quasi-solid-state electrolyte prepared in Example 2 is 1.7 × 10⁻⁶. -3 S / cm, sodium ion conductivity is 1.22×10 -3 S / cm; The lithium-ion conductivity of the 0.04M copper ion (copper acetate) hybrid biomass quasi-solid-state electrolyte prepared in Example 3 was 1.34 × 10⁻⁶. -3 S / cm, sodium ion conductivity 1.19×10 -3 S / cm; The lithium-ion conductivity of the 0.06M copper ion (copper acetate) hybrid biomass quasi-solid-state electrolyte prepared in Example 4 was 1.29 × 10⁻⁶. -3 S / cm, sodium ion conductivity is 1.11×10 -3 S / cm; The lithium-ion conductivity of the 0.02M copper ion (copper nitrate) hybrid biomass quasi-solid-state electrolyte prepared in Example 5 was 1.36 × 10⁻⁶. -3 S / cm, sodium ion conductivity is 1.13×10 -3S / cm; The lithium-ion conductivity of the 0.06M iron ion (iron acetylacetone) hybrid biomass quasi-solid-state electrolyte prepared in Example 6 was 1.26 × 10⁻⁶. -3 S / cm, sodium ion conductivity 1.08×10 -3 S / cm indicates that the transition metal hybridized biomass quasi-solid electrolyte can improve the conductivity of lithium and sodium ions compared to the unhybridized biomass quasi-solid electrolyte.

[0058] Test Example 2 The unhybridized biomass quasi-solid-state electrolyte prepared in Example 1 and the transition metal hybrid biomass quasi-solid-state electrolytes prepared in Examples 2-4 were subjected to rate performance tests in lithium metal batteries and sodium metal batteries, respectively. In all examples, the quasi-solid-state electrolytes are abbreviated as AN. The positive electrode material of the lithium metal battery is lithium iron phosphate, and the negative electrode material is lithium metal; the positive electrode material of the sodium metal battery is sodium vanadium phosphate, and the negative electrode material is sodium metal. The results are as follows: Figures 7-12 As shown.

[0059] Figure 7 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 2 in lithium batteries. Figure 8 The graph shows the rate performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 2 in a sodium battery. Figure 9 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 3 in lithium batteries. Figure 10 The graph shows the rate performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 3 in a sodium battery. Figure 11 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 4 in lithium batteries. Figure 12 The graph shows the rate performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 4 in a sodium battery.

[0060] according to Figure 7 , Figure 9 and Figure 11It can be seen that, in lithium batteries, the unhybridized biomass quasi-solid-state electrolyte prepared in Example 1 exhibits specific capacities of 157 mAh / g, 152 mAh / g, 147 mAh / g, 136 mAh / g, 119 mAh / g, and 86 mAh / g at rates of 0.1C, 0.2C, 0.5C, 1C, 2C, and 5C, respectively; while the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 2 exhibits specific capacities of 157 mAh / g, 156 mAh / g, 155 mAh / g, 143 mAh / g, 130 mAh / g, and 105 mA at rates of 0.1C, 0.2C, 0.5C, 1C, 2C, and 5C, respectively. The specific capacities of the lithium-ion batteries prepared with the transition metal hybrid biomass quasi-solid-state electrolyte in Example 3 at rates of 0.1C, 0.2C, 0.5C, 1C, 2C, and 5C were 159 mAh / g, 159 mAh / g, 153 mAh / g, 142 mAh / g, 128 mAh / g, and 98 mAh / g, respectively. The specific capacities of the lithium-ion batteries prepared with the transition metal hybrid biomass quasi-solid-state electrolyte in Example 4 at rates of 0.1C, 0.2C, 0.5C, 1C, 2C, and 5C were 160 mAh / g, 154 mAh / g, 147 mAh / g, 138 mAh / g, 124 mAh / g, and 95 mAh / g, respectively. These results indicate that the transition metal hybridized biomass quasi-solid-state electrolyte can improve the specific capacity of lithium-ion batteries at different rates compared to the unhybridized biomass quasi-solid-state electrolyte.

[0061] according to Figure 8 , Figure 10 and Figure 12It can be seen that, in sodium batteries, the specific capacities of the unhybridized biomass quasi-solid-state electrolyte prepared in Example 1 at rates of 0.5C, 1C, 2C, 5C, 10C, 20C, and 30C are 108 mAh / g, 103 mAh / g, 99 mAh / g, 85 mAh / g, 56 mAh / g, 6 mAh / g, and 4 mAh / g, respectively; and the specific capacities of the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 2 at rates of 0.5C, 1C, 2C, 5C, 10C, 20C, and 30C are 105 mAh / g, 103 mAh / g, 100 mAh / g, 94 mAh / g, 85 mAh / g, 53 mAh / g, and 36 mAh / g, respectively. / g; The transition metal hybrid biomass quasi-solid-state electrolyte prepared in Example 3 exhibited specific capacities of 105 mAh / g, 103 mAh / g, 97 mAh / g, 74 mAh / g, 55 mAh / g, 35 mAh / g, and 25 mAh / g in sodium batteries at rates of 0.5C, 1C, 2C, 5C, 10C, 20C, and 30C, respectively. The transition metal hybrid biomass quasi-solid-state electrolyte prepared in Example 4 exhibited specific capacities of 105 mAh / g, 101 mAh / g, 93 mAh / g, 72 mAh / g, 54 mAh / g, 35 mAh / g, and 24 mAh / g in sodium batteries at rates of 0.5C, 1C, 2C, 5C, 10C, 20C, and 30C, respectively. This indicates that the transition metal hybridized biomass quasi-solid-state electrolyte can improve the specific capacity of sodium batteries at different rates compared to the unhybridized biomass quasi-solid-state electrolyte.

[0062] Test Example 3 The unhybridized biomass quasi-solid-state electrolyte prepared in Example 1 and the transition metal hybrid biomass quasi-solid-state electrolytes prepared in Examples 2, 5, and 6 were subjected to long-term performance tests in lithium metal batteries and sodium metal batteries, respectively. The lithium metal batteries used lithium iron phosphate as the positive electrode and lithium metal as the negative electrode; the sodium metal batteries used sodium vanadium phosphate as the positive electrode and sodium metal as the negative electrode. The results are as follows: Figures 13-18 As shown.

[0063] Figure 13 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 2 in lithium batteries. Figure 14 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 2 in a sodium battery. Figure 15 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 5 in lithium batteries. Figure 16The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 5 in a sodium battery. Figure 17 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid-state electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid-state electrolyte of Example 6 in lithium batteries. Figure 18 The graph shows the long-term performance test results of the unhybridized biomass quasi-solid electrolyte of Example 1 and the transition metal hybridized biomass quasi-solid electrolyte of Example 6 in a sodium battery.

[0064] according to Figure 13 , Figure 15 and Figure 17 It can be seen that the unhybridized biomass quasi-solid-state electrolyte prepared in Example 1, when applied to a lithium battery, retains 89% of its capacity after 170 cycles at 0.5C; the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 2, when applied to a lithium battery, retains 95% of its capacity after 170 cycles at 0.5C; the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 5, when applied to a lithium battery, retains 98% of its capacity after 170 cycles at 0.5C; and the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 6, when applied to a lithium battery, retains 93% of its capacity after 170 cycles at 0.5C. This indicates that lithium batteries prepared with transition metal hybridized biomass quasi-solid-state electrolytes can maintain a higher capacity retention rate after long-term cycling compared to lithium batteries prepared with unhybridized biomass quasi-solid-state electrolytes.

[0065] according to Figure 14 , Figure 16 and Figure 18 It can be seen that the unhybridized biomass quasi-solid-state electrolyte prepared in Example 1, when applied to a sodium battery, retains 88% of its capacity after 500 cycles at 1C; the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 2, when applied to a lithium battery, retains 94% of its capacity after 500 cycles at 1C; the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 5, when applied to a lithium battery, retains 93% of its capacity after 500 cycles at 1C; and the transition metal hybridized biomass quasi-solid-state electrolyte prepared in Example 6, when applied to a lithium battery, retains 90% of its capacity after 500 cycles at 1C in long-term performance testing of sodium batteries. This indicates that sodium batteries prepared with transition metal hybridized biomass quasi-solid-state electrolytes can maintain a higher capacity retention rate after long-term cycling compared to sodium batteries prepared with unhybridized biomass quasi-solid-state electrolytes.

[0066] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for preparing a filamentous fungal biofilm, characterized in that, Includes the following steps: Filamentous fungal spores were cultured in the first stage to obtain filamentous fungi; The filamentous fungi were immersed in a treatment solution for a second stage of culture to obtain the treated filamentous fungi; The treated filamentous fungi are cold-pressed to obtain the filamentous fungal biofilm; The treatment solution is a transition metal salt solution or deionized water.

2. The preparation method according to claim 1, characterized in that, The filamentous fungi include Aspergillus niger, Aspergillus oryzae, Trichoderma reesei, or Penicillium chrysogenum.

3. The preparation method according to claim 1 or 2, characterized in that, The first stage of cultivation is carried out in a culture medium, which includes a sugar source, a nitrogen source and water, and the mass ratio of the sugar source, nitrogen source and water is 2~3:1.5~2:100; the temperature of the first stage of cultivation is 25~40℃ and the time is 16~72h.

4. The preparation method according to claim 1, characterized in that, The transition metal salt in the transition metal salt solution includes copper salt, iron salt, manganese salt or zinc salt; the concentration of the transition metal salt solution is 0.01~0.06 mol / L; the temperature of the second stage of cultivation is 25~40℃ and the time is 24~48h.

5. The preparation method according to claim 1, characterized in that, The hyphae of the filamentous fungi being treated have a diameter of 1.5~2μm; the pressure of the cold pressing is 1~6MPa.

6. The filamentous fungal biofilm prepared by the preparation method according to any one of claims 1 to 5, characterized in that, It can be a transition metal hybrid biomass membrane or a non-hybrid biomass membrane.

7. The application of the filamentous fungal biofilm according to claim 6 in quasi-solid electrolytes.

8. A quasi-solid-state electrolyte based on filamentous fungal biomass, characterized in that, It includes a filamentous fungal biomass membrane and an electrolyte solution permeating the filamentous fungal biomass membrane; the filamentous fungal biomass membrane is the filamentous fungal biomass membrane of claim 6; the electrolyte solution is a lithium battery electrolyte or a sodium battery electrolyte.

9. The quasi-solid-state electrolyte based on filamentous fungal biomass according to claim 8, characterized in that, The thickness of the filamentous fungal biomass quasi-solid electrolyte is 0.3~0.8 mm, and the lithium content in the filamentous fungal biomass quasi-solid electrolyte is 5.041~5.058 ppm, and the sodium content is 4.992~5.012 ppm.

10. The application of the filamentous fungal biomass quasi-solid-state electrolyte of claim 8 or 9 in lithium metal batteries or sodium metal batteries.

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