50results about How to "Improve long cycle stability" patented technology

The invention belongs to the technical field of lithium ion batteries, and discloses a carbon compatible binder for a silicon-carbon negative electrode of a lithium ion battery and a preparation method and application of the carbon compatible binder for the silicon-carbon negative electrode of the lithium ion battery. Then N-hydroxysuccinimide and 1-ethyl-(3-dimethylaminopropyl) carbodiimide are added to activate carboxyl of sodium carboxymethyl cellulose, finally 1-pyrene methylamine hydrochloride is added, N2 is introduced at the room temperature, and a reaction is performed under stirring. According to the binding agent, sodium carboxymethyl cellulose is used as a main chain to be subjected to amidation reaction with 1-pyrene methylamine hydrochloride, pi-pi conjugation can be formed by introduced pyrene groups and graphite in a silicon-carbon material, the interface compatibility of the binding agent and the silicon-carbon material can be effectively improved, the dispersity and the binding property of the silicon-carbon material are enhanced, and the binding agent can be used for preparing the silicon-carbon material. And the electrochemical performance of the silicon-carbon negative electrode of the lithium ion battery is obviously improved.

The invention discloses a silicon-carbon negative electrode material preparation method, which comprises: (S1) uniformly mixing a water-soluble resin and a transition metal salt aqueous solution, and drying to obtain a resin-loaded metal salt composite material; (S2) carrying out carbonization treatment on the resin-loaded metal salt composite material, and then carrying out reduction treatment to obtain metal-loaded porous carbon; (S3) placing the metal-loaded porous carbon in a mixed atmosphere containing carbon dioxide and acetylene, performing in-situ growth of carbon nanotubes in the porous carbon, and performing acid pickling to obtain modified porous carbon; and (S4) by taking the modified porous carbon as a substrate, sequentially carrying out silicon deposition and carbon coating to obtain the silicon-carbon negative electrode material. According to the preparation method of the silicon-carbon negative electrode material disclosed by the invention, the porous carbon is synthesized in situ, and the carbon nanotubes grow in the porous carbon in situ, so that more buffer spaces are provided for volume expansion of nano silicon particles from the angle of substrate preparation, and the long cycle stability of the silicon-carbon negative electrode material is remarkably improved.

The invention discloses a three-dimensional porous current collector as well as a preparation method and application thereof, belongs to the technical field of a sodium metal battery current collector, and solves the problem that the electrochemical performance of a metal sodium battery without a negative electrode in the prior art is not ideal enough. The three-dimensional porous current collector comprises a copper substrate and bismuth nanosheets vertically grown on the surface of the copper substrate, wherein the copper substrate is of a net structure, and the bismuth nanosheet is of a three-dimensional honeycomb structure. The three-dimensional porous current collector provided by the invention has ultra-stable sodium deposition stripping performance and excellent long cycle stability.

The invention belongs to the technical field of eutectic electrolytes, and provides a bicontinuous eutectic electrolyte and a preparation method and application thereof. The bicontinuous eutectic electrolyte provided by the invention has a clear microcosmic bicontinuous phase separation structure, an ion phase region (deep eutectic electrolyte) can realize efficient ion transmission, and a mechanical phase region can ensure sufficient mechanical support; therefore, according to the bicontinuous eutectic electrolyte, the ionic conduction performance and the mechanical performance can be synergistically improved, so that the electrochemical performance and the safety performance of the lithium ion battery are improved, and macroscopically, the bicontinuous eutectic electrolyte has long cycle stability. Meanwhile, at least two of 2, 2, 2-trifluoroethyl acrylate, 2-(perfluorobutyl) ethyl methacrylate and perfluorohexyl ethyl acrylate are used as polymer monomers, so that the fluorine content of the bicontinuous eutectic electrolyte is high, and the long cycle stability of the bicontinuous eutectic electrolyte can be further improved.

The invention belongs to the field of sodium-ion batteries, and discloses a sodium-ion battery electrolyte and a sodium-ion battery. The sodium-ion battery electrolyte comprises sodium salt, an organic solvent and an organic molecular additive shown in the following formula, wherein R1 to R5 are respectively and independently any one of F, Cl, Br, I, CN, H, OH, SH and NO2. A boron atom in the molecular structure of the additive is used as an electron-deficient center and can be preferentially complexed with anions or solvent molecules in the electrolyte to pre-stabilize an electrode interface; the bond energy of the B-O bond is moderate, so that the oxidation potential of the B-O bond is lower than that of a main body carbonate solvent, the B-O bond can be preferentially decomposed in the first charge-discharge process, and a thin, compact and highly stable positive electrode electrolyte interface film is formed on the surface of a positive electrode; the controllable substituent group on the benzene ring further regulates the decomposition potential of molecules through an electronic effect, so that the film forming time and the film property can be precisely regulated and controlled. The stable CEI can effectively inhibit continuous decomposition of the electrolyte at high temperature and high pressure, and the cycling stability of the battery in the high-temperature and high-pressure environment is remarkably improved.

The application provides a porous carbon nanofiber electrocatalyst loaded with cobalt / lanthanum hydroxide heterojunction and a preparation method. The preparation method comprises the following steps: adding 4,4-diamino diphenyl ether and pyromellitic dianhydride into a solvent, uniformly mixing, and preparing a polyamide acid precursor spinning solution; electrospinning the prepared polyamide acid precursor spinning solution to prepare polyamide acid nanofibers; immersing the prepared polyamide acid nanofibers in a mixed metal salt solution containing cobalt salt, lanthanum salt and zinc salt to prepare polyamide acid nanofiber precursors loaded with metal ions; and performing programmed temperature heat treatment on the prepared polyamide acid nanofiber precursors loaded with metal ions in a protective atmosphere to prepare the porous carbon nanofiber electrocatalyst loaded with cobalt / lanthanum hydroxide heterojunction. The prepared porous carbon nanofiber electrocatalyst loaded with cobalt / lanthanum hydroxide heterojunction has excellent electrochemical oxygen reduction reaction and oxygen evolution reaction bifunctional catalytic activity.

This invention discloses a zirconium-lanthanum bulk co-doped high-nickel ternary material, its preparation method, and a battery. The zirconium-lanthanum bulk co-doped high-nickel ternary material is a ternary cathode material with bulk co-doped zirconium and lanthanum; the chemical formula of the ternary cathode material is LiNi. x Co y Mn (1‑x‑y) O2, wherein 0.8≤x≤0.9, 0≤y≤0.1; the total molar amount of zirconium and lanthanum is 1%~5% of the total molar amount of nickel, cobalt and manganese. The zirconium-lanthanum bulk co-doped high-nickel ternary material provided by the present invention enhances the mechanical strength of the ternary material through the bulk co-doping of zirconium and lanthanum, suppresses cracking and pulverization of the ternary material during charge and discharge, and improves cycle stability; at the same time, the two elements Zr and La synergistically stabilize the lattice, reduce lithium-nickel mixing, suppress irreversible phase transformation and lattice oxygen precipitation, achieve dual stability of bulk phase and interface, and improve the consistency and stability of the zirconium-lanthanum bulk co-doped high-nickel ternary material.

The present invention provides a rare earth metal modified layered positive electrode material for sodium ion batteries and a preparation method thereof. The main structure of the rare earth metal modified layered positive electrode material for sodium ion batteries is an O3 phase, and the chemical formula is NaNi a Fe b Mn c Re d O 2 , 0.28≤a≤0.33, 0.28≤b≤0.33, 0.28≤c≤0.33, 0≤d≤0.05, Re represents a rare earth metal element; the layered positive electrode material includes spherical secondary particles, the secondary particles include a plurality of stacked flaky primary particles, part of the rare earth metal elements are distributed on the surface of the secondary particles in the form of rare earth metal oxides, and part of the rare earth metal elements are doped in the layered positive electrode material lattice in the form of rare earth metal ions. The positive electrode material provided by the present invention is modified based on rare earth metal elements, and has good sphericity and rich pore structure. The battery containing the positive electrode material exhibits excellent rate performance and good cycle stability.

According to the preparation method of the heterostructure sodium electric layered oxide positive electrode material, the positive electrode material is of a heterostructure and comprises a P2 and O3 two-phase structure, and a potassium ion layered oxide precursor is subjected to ion exchange and heat treatment to obtain the heterostructure sodium electric layered oxide positive electrode material. According to the preparation method provided by the invention, the sodium electric layered oxide positive electrode material with a P2 / O3 heterostructure can be obtained. In the ion exchange process, sodium ions separated from the sodium-containing molten salt and potassium ions of the potassium ion layered oxide are replaced, under the driving of the chemical potential gradient, intercalation of the sodium ions is accompanied with separation of the potassium ions, the interlayer spacing is gradually reduced under the action of coulomb force, and the P phase is gradually converted into the O phase. According to the invention, the sodium electric layered oxide material with high rate capability and cycling stability is obtained; the material has the fast charging performance, and meanwhile, the long circulation stability is improved. The sodium battery positive electrode material obtained by the method is stable in structure and easy for large-scale application.

The invention relates to the technical field of aqueous zinc ion batteries, and discloses a high-utilization-rate and high-stability zinc electrode as well as a preparation method and application thereof. The zinc electrode comprises a base body and a functional coating attached to the surface of the base body, and the functional coating is formed by coating the surface of the base body with slurry formed by zinc powder, an adhesive and a functional additive and drying the slurry. According to the obtained zinc electrode, the zinc ion diffusivity under the high DOD condition can be remarkably improved, the free water induced parasitic side reaction and the stress cracking problem caused by the volume effect are inhibited, the long circulation stability under the high zinc metal utilization rate (15-96%) condition is prolonged, and the good application prospect is shown in a low N / P zinc-based device.

This invention provides a MoS2 / MoP@Ti3C2T x The research on heterostructured composite materials and their application in lithium-sulfur battery separators relates to the field of electrochemical energy storage materials and devices. The aforementioned composite material is constructed using an electrostatic self-assembly strategy, enabling MoS₂ / MoP heterostructure nanoparticles to be uniformly anchored on a monolayer of Ti₃C₂T. x Fabricated on the surface of nanosheets, this structure effectively inhibits the aggregation and stacking of components, maximizing the exposure of active interfaces. Among them, the highly conductive Ti₃C₂T... x The network ensures rapid electron transport, while the MoS₂ / MoP heterojunction provides strong chemisorption and efficient bidirectional electrocatalytic conversion of lithium polysulfides. Coating the aforementioned composite material onto a polypropylene separator as a modification layer significantly improves the overall performance of lithium-sulfur batteries, resulting in excellent rate performance and long-term cycle stability.

A vacancy composite diaphragm and its preparation method, application and lithium-based liquid battery based thereon, as well as a solid-state battery. The present invention belongs to the field of lithium battery diaphragms. The present invention is to solve the technical problems that the existing lithium-based batteries cannot achieve the simultaneous improvement of lithium ion conductivity and lithium ion migration number, and the existing modification method using ceramic particles directly coated or as fillers leads to diaphragm pore blockage, which is not conducive to the high rate performance and long cycle stability of lithium ion batteries. The present invention adds Te-rich vacancy particles to the diaphragm substrate to obtain a vacancy composite diaphragm with uniform pore size, precisely controllable thickness, high lithium ion conductivity, high lithium ion migration number, good electrolyte absorption rate and good wettability. The introduction of Te-rich vacancy particles effectively limits the migration of anions in the electrolyte, greatly improves the migration ability of lithium ions, and can also homogenize lithium ion deposition, inhibit the growth of lithium dendrites, and improve the rate performance and cycle stability of lithium batteries.

The application belongs to the technical field of lithium ion batteries, and discloses a carbon-compatible binder for a silicon-carbon negative electrode of a lithium ion battery, a preparation method and application thereof, wherein the carbon-compatible binder is abbreviated as CMC-Py, sodium carboxymethyl cellulose is dissolved in a phosphate buffer solution, then N-hydroxysuccinimide and 1-ethyl-(3-dimethylaminopropyl) carbodiimide are added to activate the carboxyl group of the sodium carboxymethyl cellulose, finally, 1-pyrenemethylamine hydrochloride is added, and the reaction is carried out under stirring and N2 at room temperature to obtain the binder. The binder is prepared by the amidation reaction of sodium carboxymethyl cellulose as a main chain and 1-pyrenemethylamine hydrochloride, the pyrene group introduced can form a pi-pi conjugated system with graphite in the silicon-carbon material, the interface compatibility of the binder and the silicon-carbon material can be effectively improved, the dispersibility and the adhesion of the silicon-carbon material can be enhanced, and the electrochemical performance of the silicon-carbon negative electrode of the lithium ion battery is significantly improved.

The application provides a high-capacity and high-rate hard carbon negative electrode material and a preparation method and application thereof, and belongs to the technical field of sodium ion battery negative electrode materials. Specifically, biomass shell raw materials are coarsely broken and sieved to obtain biomass coarse powder; the biomass coarse powder is mixed with an oxidizing agent and then pre-oxidized; mechanical pulverization is performed to obtain biomass coarse powder with a D50 of 8-15 microns; the biomass coarse powder is added into mixed acid and heated in a water bath, and then washed with water until neutral to obtain a purified precursor; and finally, the precursor is subjected to staged high-temperature carbonization in a vacuum carbonization furnace. Through specific process parameters, the prepared hard carbon material has a hierarchical porous structure and a suitable graphite microcrystalline layer spacing, and has a low total content of metal impurities; when applied to a sodium ion battery negative electrode, the hard carbon material exhibits a high reversible specific capacity, a high initial coulombic efficiency, and excellent long cycle stability and rate performance.

The invention discloses an oxygen reduction electrocatalyst and a preparation method and application thereof, and relates to the field of catalysis. The oxygen reduction electrocatalyst comprises a carrier and a metal monatomic loaded on the carrier, the carrier is nitrogen-sulfur double-doped porous carbon, the coordination structure of the metal monatomic and the nitrogen-sulfur double-doped porous carbon is N3S1M1, and M is a metal element corresponding to the metal monatomic. The oxygen reduction electrocatalyst provided by the invention does not contain noble metal, is relatively low in cost, is a monatomic catalyst in nature, and has extremely high atom utilization rate. The oxygen reduction electrocatalyst has a relatively large specific surface area, shows excellent oxygen reduction catalytic activity in an alkaline medium, and shows excellent long cycle stability in a water system and a flexible zinc air battery positive electrode, so that the oxygen reduction electrocatalyst has great application potential.

The invention relates to a triazinyl covalent organic framework coated nano silicon negative electrode, a preparation method and application thereof, and belongs to the technical field of lithium ion batteries. Melamine and nano silicon are combined through Van der Waals' force, electrostatic adsorption and more than one of acting forces of peptide bonds, then pyromellitic dianhydride and melamine are cross-linked through secondary amine bonds, and finally a triazinyl covalent organic framework coating layer is formed on the surface of nano silicon. In the lithiation process, a C = N bond on a triazine ring serves as a reaction site to be preferentially combined with lithium ions to be converted into an inorganic Li3N component, and Li3N has high modulus, so that the mechanical strength of an SEI film is effectively improved, SEI film breakage caused by volume expansion of a silicon negative electrode is avoided, and the cycle life of the electrode is prolonged. The synthesized negative electrode material has excellent long cycle stability when being applied to a negative electrode of a lithium ion battery.

A kind of high nickel precursor, positive electrode material and preparation method thereof, belong to the technical field of lithium ion battery materials, overcome the defect that doping elements are unevenly distributed in the material body when the prior art prepares high nickel precursor. The preparation method of the high nickel precursor of the present invention comprises the following steps: step 1, prepare Al-containing nickel cobalt manganese salt solution, ammonia solution, alkali solution precipitant and ammonia bottom liquid; in the Al-containing nickel cobalt manganese salt solution, the Al / TM atomic ratio is 0.001-0.01, and TM is the sum of the amount of substance of nickel, cobalt and manganese atoms; step 2, add the ammonia bottom liquid to the reactor, and adjust the pH of the ammonia bottom liquid to 10.7-11.7, pump the Al-containing nickel cobalt manganese salt solution, ammonia solution and alkali solution precipitant into the reactor at the same time, stir during the feeding process, and continue stirring reaction after the feeding ends; step 3, solid-liquid separation, washing, drying to obtain a high nickel precursor. The present invention can reduce the generation of particle microcracks and improve the long cycle stability of the material.

The application discloses an asymmetric hybrid mesoporous material and a preparation method and application thereof, and belongs to the technical field of mesoporous materials; the preparation method comprises the following steps: taking a template agent, a pore expanding agent and an organic silicon source as the basis, combining SiO2 nanospheres and an organic silane capping agent to prepare superstructure silicon spheres; then, the superstructure silicon spheres are dispersed in an alcohol-water mixed solvent, dopamine hydrochloride is added, and in-situ polymerization is carried out under the action of ammonia water to obtain an asymmetric mesoporous material. The material has a high specific surface area and a rich hierarchical pore structure, and the mesoporous superstructure silicon sphere constructed by the SiO2 nanospheres is one end, and the polydopamine layer is the other end. The application has the advantages of simple process and mild conditions, and the material morphology and size can be controlled by adjusting reaction parameters. When the material is applied to a water-based zinc ion battery negative electrode, the specific capacity, cycle stability and rate performance of the battery can be significantly improved, the zinc dendrite growth and side reactions can be effectively inhibited, and the material has important energy storage application value.

The application discloses the use of open-chain diimine compounds shown in formula (I) or formula (II) as electrolyte additives: R1-L1-N=C-Ph-C=N-L2-R2 (I) R1-L1-C=N-Ph-N=C-L2-R2 (II) wherein, L1, L2 are each independently selected from a single bond, substituted or unsubstituted C 1‑10 alkylene, substituted or unsubstituted phenylene; Ph is 1,4-phenylene or perfluoro-1,4-phenylene; R1, R2 are each independently selected from cyano, substituted or unsubstituted C 1‑10 alkyl, substituted or unsubstituted C 2‑10 alkyl, substituted or unsubstituted C 2‑10 alkyne, substituted or unsubstituted phenyl, significantly improves the long cycle stability of high-nickel ternary positive electrode materials, and solves the problem of rapid cycle capacity decay of the prior art electrolyte when matched with high-nickel positive electrodes at high voltage.

The application discloses a kind of sodium iron silicate negative materials and preparation method thereof.The method uses phosphating by-product silicon slag as silicon source, uses iron salt and sodium salt as raw material, uses template agent and solvent as auxiliary, and obtains the irregular spherical particle sodium iron silicate negative material by sol-gel method combined with stepwise heating calcination process.The application realizes high-value utilization of phosphating solid waste, and the prepared material has stable structure and exhibits high reversible capacity and excellent cycle stability when used as sodium-ion battery negative material.The method is simple, green and environmentally friendly, and low in cost, suitable for industrial production.

The application relates to the technical field of all-solid-state lithium batteries, and discloses an oxyfluoride active substance and a preparation method and application thereof, the preparation method steps are as follows: FeF3.3H2O and transition metal fluoride are mixed and ground, and then ball milling is carried out; the ball milling product is added into an organic solvent to carry out a solvothermal reaction, and after the reaction is completed, cooling and standing are carried out; the FeF3.3H2O is dispersed in the organic solvent, and after uniform stirring, the system after standing is dripped into, and then the solvothermal reaction is continuously carried out by heating; after the reaction is completed, the product is separated and dried to obtain the oxyfluoride active substance. The oxyfluoride active substance with a core-shell gradient structure is constructed through step-by-step high-energy ball milling and controlled heat treatment, the band gap and the crystal structure of the material are accurately controlled, and therefore a fluorine oxide-based composite positive electrode material with the advantages of structural stability, fast ion transmission kinetics, good interface compatibility, high specific capacity and good cycle stability is obtained.

The application discloses a composite nanofiber membrane, a modified nanofiber membrane and application thereof, and relates to the technical field of nanofiber membranes.The composite nanofiber membrane comprises a first electrolyte layer, a modified nanofiber membrane and a second electrolyte layer arranged in sequence.The first electrolyte layer comprises iron phthalocyanine, a first polymer and a first electrolyte lithium salt, and the second electrolyte layer comprises a second polymer and a second electrolyte lithium salt.The modified nanofiber membrane comprises modified nanofibers and a three-dimensional porous structure grown in situ on the modified nanofibers.The modified nanofibers contain ferrous iron, and the material of the three-dimensional porous structure contains iron phthalocyanine.The composite nanofiber membrane greatly improves the content of the electrolyte amorphous region, improves the dissociation of the electrolyte lithium salt, promotes the increase of ionic conductivity and ionic transference number, reduces the generation of side reactions, and is beneficial to realizing stable and long-acting interface performance.

The present invention belongs to the field of synthesis of electrode materials, and particularly relates to a type of polycarbonyl hexaazatriphenylene derivative type COF and a preparation method thereof for aqueous zinc ion battery positive electrode materials. Hexaazatriphenylene hexacarboxylic acid trianhydride is subjected to a dehydration condensation reaction with terephthalic acid dihydrazine or N, N-1,4-phenylene bis (thiourea), and after the reaction is completed, heating is stopped, deionized water, ethanol, and acetone are added for washing, and suction filtration is performed to obtain a polycarbonyl hexaazatriphenylene derivative type covalent organic framework (COF), which is used to prepare aqueous zinc ion battery positive electrode materials, and has high specific capacity, excellent cycle stability, and excellent chemical (air) self-charging performance, therefore, in aqueous zinc ion battery electrode materials and flexible electronic products, it has broad application prospects. The synthesis method of the material of the present invention is simple, the source of raw materials is abundant, and the reproducibility is good, which is suitable for industrial production.

This invention belongs to the field of electrode material technology, specifically relating to a multi-level nanostructure, dual-phase Co-Li4Ti5O 12 / TiO2 / C composite material, its preparation method, and its application. The composite material also contains the spinel phase Li4Ti5O. 12 The composite material is composed of anatase TiO2, doped with Co, and coated with a carbon layer. The preparation method of the composite material is as follows: Titanium, lithium, and cobalt sources are dissolved in anhydrous ethanol to obtain solution A; a carbon source is dissolved in water to obtain solution B; solution B is added dropwise to solution A; after the hydrothermal reaction is completed, the mixture is treated and calcined to obtain a multi-level nanostructured, two-phase interface composite material. The multi-level nanostructured, two-phase interface Co-Li4Ti5O2 composite material provided by this invention... 12 The preparation method of / TiO2 / C composite material is simple and low-cost. Applying the composite material to lithium-ion batteries can improve the chemical performance of the batteries and extend their lifespan.

This invention discloses a P2-type NaCrFeTi layered oxide, which is obtained by high-temperature solid-state sintering using sodium carbonate, iron oxide, chromium oxide, and titanium dioxide as raw materials. 0.67 Cr 1 / 3 Fe 1 / 3 Ti 1 / 3O2 layered oxide NCFT-33 / 33; belonging to the P2 phase structure of the P63 / mmc space group; microstructure is a hexagonal prism structure with a particle size of 1-3 micrometers, exhibiting a single-crystal structure; the main phase content reaches over 95%. Its preparation method is a one-step sintering method, where raw materials are ball-milled and mixed according to the chemical formula ratio, followed by sintering and natural cooling. When used as a sodium-ion battery anode material, the reversible specific capacity is 60.00-80.00 mAh g. ‑1 When the number of cycles is 3000, the capacity retention rate is 91-93%, and the capacity loss rate per cycle is only 0.0023-0.0030%.

The present application provides a method for preparing an iron-atom-substituted zinc sulfide negative electrode material for a potassium ion battery, comprising: uniformly mixing ammonium ferric citrate, L-cysteine ​​and deionized water to form a solution A; uniformly mixing zinc nitrate hexahydrate and deionized water to form a solution B; uniformly mixing dimethyl imidazole and deionized water to form a solution C; uniformly mixing solution A, solution B and solution C in a weight ratio of 1:2:2-1.5:2:2 to obtain a precursor solution, centrifuging the precursor solution to collect a precursor powder; annealing the precursor powder under an inert atmosphere to obtain an iron-atom-substituted zinc sulfide negative electrode material, which, when applied to a potassium ion battery negative electrode material, can be used at 100 mAg ‑1 At this current density, the specific capacity can still be maintained at 583.9 mAh g after 240 cycles. ‑1 The present application also provides an iron atom-substituted zinc sulfide negative electrode material and a potassium ion battery.

The present application provides a manganese sulfide-molybdenum disulfide heterojunction lithium-sulfur battery positive electrode host material, with molybdenum disulfide nanosheets as the main body, and manganese sulfide nanoparticles are anchored on the molybdenum disulfide nanosheets to form a composite material with a manganese sulfide-molybdenum disulfide heterostructure. The present invention adds manganese disulfide tetrahydrate, anhydrous sodium molybdate and thioacetamide into ultrapure water, stirs at room temperature, and reacts by hydrothermal method to obtain a manganese sulfide-molybdenum disulfide heterojunction composite material. The preparation process of the present invention is short and the process is simple, and the experimental repeatability is good. The prepared manganese sulfide-molybdenum disulfide heterojunction composite material has high electronic conductivity, high catalytic activity for polysulfur intermediate species, and strong chemical adsorption for polysulfides, which effectively alleviates the shuttle effect and improves the kinetics of the electrode reaction process.

The invention belongs to the technical field of material preparation, and discloses a hierarchical pore carbon metamaterial for a zinc ion supercapacitor and a preparation method of the hierarchical pore carbon metamaterial, the hierarchical pore carbon metamaterial is of a 2D / 3D Z-type heterostructure, and the surface of the hierarchical pore carbon metamaterial is provided with ZIF-8 micropores and a DQTT polymer mesoporous structure. ZIF-8 is prepared through reaction of 2-methylimidazole and zinc nitrate hexahydrate, a DQTT polymer formed by 2, 6-diamino-anthraquinone and 2, 4, 6-trichloro-1, 3, 5-triazine grows on the surface of the ZIF-8 in situ through physical adsorption and chemical action, and the hierarchical porous carbon metamaterial is finally obtained through carbonization, activation and acidification treatment. The equilibrium relationship between ZIF-8 micropores and DQTT polymer mesopores is adjusted by controlling the activation ratio to realize accurate design of pore characteristics, and the hierarchical pore carbon metamaterial with ultrahigh specific surface area, rich heteroatom content and good electrochemical stability is obtained.

The invention relates to the technical field of batteries, and provides an ionic liquid additive for improving the interface stability of a hard carbon negative electrode of a sodium-ion battery and application of the ionic liquid additive in order to solve the problems of low ion transmission rate, poor electrode / electrolyte interface stability and the like of the hard carbon negative electrode in practical application in the prior art. The electrolyte prepared based on the ionic liquid additive comprises electrolyte salt, the ionic liquid additive and an organic solvent, wherein the electrolyte salt is sodium salt; the ionic liquid additive is pyrrolidine type dication ionic liquid, and the organic solvent is one or a mixture of carbonic ester or ether solvents. The electrolyte prepared by the invention not only improves the migration ability of Na < + >, but also promotes the construction of a compact and uniform SEI film. A NaHC half battery and a total battery assembled by an electrolyte prepared from the dicationic ionic liquid additive provided by the invention can significantly improve the long cycle stability. After the NaHC half cell circulates 400 times under the current density of 100 mA / g, the capacity retention rate reaches 90.4%.

The application relates to the technical field of lithium ion batteries, in particular to a high-entropy high-nickel cobalt-free precursor, a high-entropy high-nickel cobalt-free single-crystal positive electrode material and a preparation method thereof and a lithium ion battery. The high-entropy high-nickel cobalt-free precursor comprises a core layer and a high-entropy doped shell layer coated on at least part of the surface of the core layer; the core layer comprises a first nickel-manganese hydroxide; the high-entropy doped shell layer comprises a high-entropy doped second nickel-manganese hydroxide; and the doped elements in the high-entropy doped second nickel-manganese hydroxide include titanium, magnesium, aluminum, zirconium and molybdenum. The high-entropy high-nickel cobalt-free precursor provided by the application is coated with a high-entropy doped shell layer containing titanium, magnesium, aluminum, zirconium and molybdenum on the surface of the core layer containing the first nickel-manganese hydroxide, which is beneficial to reducing the exposure degree of {010} active crystal faces in the precursor, promoting the preferred growth of the positive electrode material along the (003) plane, and further improving the electrochemical performance and cycle stability of the high-entropy high-nickel cobalt-free single-crystal positive electrode material.