657 results about "Lithium sulfide" patented technology

Batteries including a lithium electrode and a sulfur counter electrode that demonstrate improved cycling efficiencies are described. In one embodiment, an electrochemical cell having a lithium electrode and a sulfur electrode including at least one of elemental sulfur, lithium sulfide, and a lithium polysulfide is provided. The lithium electrode includes a surface coating that is effective to increase the cycling efficiency of said electrochemical cell. In a more particular embodiment, the lithium electrode is in an electrolyte solution, and, more particularly, an electrolyte solution including either elemental sulfur, a sulfide, or a polysulfide. In another embodiment, the coating is formed after the lithium electrode is contacted with the electrolyte. In a more particular embodiment, the coating is formed by a reaction between the lithium metal of the lithium electrode and a chemical species present in the electrolyte.

Batteries including a lithium anode stabilized with a metal-lithium alloy and battery cells comprising such anodes are provided. In one embodiment, an electrochemical cell having an anode and a sulfur electrode including at least one of elemental sulfur, lithium sulfide, and a lithium polysulfide is provided. The anode includes a lithium core and a ternary alloy layer over the lithium core where the ternary alloy comprises lithium and two other metals. The ternary alloy layer is effective to increase cycle life and storageability of the electrochemical cell. In a more particular embodiment, the ternary alloy layer is comprised of lithium, copper and tin.

The invention relates to a novel carbon-sulfur compound for an anode material of a lithium-sulfur battery and a preparation method thereof. Sulfur is filled into a nano and micron hole of a matrix in an elementary substance way by taking a macroporous carbon material with high pore volume, electrical conductivity and specific surface area as the matrix, and the sulfur and carbon can also carry out combination reaction so as to prepare the novel carbon-sulfur compound of which the sulfur exists in one or more chemical states in a carbon material. The novel carbon-sulfur compound used as the anode material of the lithium-sulfur battery has the advantages that the high pore volume has large contained sulfur contents and can ensure high electric capacity; the small granularity of the sulfur can reduce a conductive distance between ions and electrons and increase the utilization ratio of the sulfur; and the adsorption characteristics of the high specific surface of the carbon material can inhibit a discharging intermediate product from dissolving and moving towards a cathode, reduce the self discharge, prevent a nonconductive discharging product, namely lithium sulfide from largely accumulating outside carbon particles and reduce internal resistance, therefore, the material can improve the specific energy, the specific power and the cycle performance of the lithium-sulfur battery.

A solid electrolyte sheet including: 80 to 99 wt % of an inorganic solid electrolyte, and 1 to 20 wt % of a binder; the inorganic solid electrolyte being obtainable by firing a raw material containing lithium sulfide (Li2S) with phosphorus pentasulfide (P2S5), or elemental phosphorus and elemental sulfur.

The invention discloses a lithium-sulphur battery anode material, which adopts the technical scheme that elemental sulphur or lithium sulfide is loaded into one or various carrier materials to form a novel composite electrode for a lithium-sulphur battery. The carrier material (s) is (are) characterized in that within the operation voltage range of the elemental sulphur or the lithium sulfide, the carrier material (s) is (are) also provided with electrochemical activity, that is, is (are) provided with considerable lithium storage capacity, and simultaneously has (have) characteristics of high specific surface and high porosity. The invention also discloses a preparation method of the lithium-sulphur battery anode material. The system of the electrode solves problems that the carrier material of a conventional lithium-sulphur battery anode material is not provided with the electrochemical activity and is low in composite material specific capacity within the operation voltage range of the elemental sulphur or the lithium sulfide, and the integral specific capacity of the composite electrode and the energy density of the lithium-sulphur battery are improved.

The invention provides a lithium sulfide-porpous carbon compound positive material for a lithium ion battery and a preparation method thereof. The positive material is formed by compounding lithium sulfide and ordered porous carbon, wherein the mass fraction of the lithium sulfide in the compound material is 20-80%; and the lithium sulfide exists in the pore spaces of the porous carbon. The preparation method comprises the following steps: firstly, carrying out ball milling on the ordered porous carbon and sulfur in the presence of inert gas; then carrying out thermal processing on the milled mixture at the temperature of 145-155 DEG C so that the sulfur fully is dispersed into the porous carbon; and finally, reacting lithium with the sulfur so as to generate the lithium sulfide by a chemical or electrochemical method, thereby obtaining the positive material provided by the invention. According to the invention, the preparation process is simple, and the raw material source is wide; the prepared positive material is used in a mode of pre-embedding lithium in a positive electrode, metal lithium is not required to serve as a negative electrode, and a carbon negative electrode, a silicon negative electrode and the like are used, thereby improving the safety performance and the assembling performance; the positive material has the advantages of good conductivity, high capacity and good circulation performance; and the positive material has a wide application prospect and the preparation method is suitable for industrial production.

A chemical source of electrical energy may include a positive electrode (cathode) made of an electrically conductive material, a mixture of lithium sulphide and sulphur, a permeable separator or membrane, and a negative electrode (anode) made of an electrically conductive material or a material that is able reversibly to intercalate lithium ions, wherein an aprotic electrolyte comprising at least one lithium salt in at least one solvent is provided between the electrodes.

The invention relates to a production method of a boron nitride coated diaphragm of a lithium-sulfur battery. The diaphragm is produced from a commercial polypropylene diaphragm, two sides of the diaphragm are uniformly covered with hexagonal boron nitride, and the characteristics of hexagonal boron nitride 'white graphite' are used, so lithium ions are allowed to pass, shuttle of polysulfide anions is obstructed, a reaction of a lithium negative electrode with the polysulfide anions is inhibited, formation of lithium dendrites, lithium sulfide precipitate and fixed lithium is prevented, the capacity, the coulombic efficiency and the cycle stability of the lithium-sulfur battery are improved, the growth of the negative electrode metal dendrite in the cycle process is effectively inhibited, and the safety of the battery is improved. The method has the advantages of simple process route and clear purpose, and the produced diaphragm has multiple functions, and can greatly overcome disadvantages of present technologies.

The invention discloses a lithium-sulfur battery. The lithium-sulfur battery comprises three-dimensional porous graphene covalence fixing nanometer lithium sulfide as a composite positive electrode, a polyolefin membrane coated with graphene oxide as a modified membrane, and a lithium sheet negative electrode and an electrolyte which are generally adopted. The particle size of lithium sulfide in the composite positive electrode is between 1 nm and 100 nm, and the lithium sulfide is combined with oxygen-containing functional groups on the surface of three-dimensional porous graphene in the form of a C-O-S covalent bond. The modified membrane is prepared from graphene oxide with the thickness of 0.1 to 10 microns uniformly deposited on the surface of a traditional polyolefin membrane; and the graphene oxide can be coated on both sides of the polyolefin membrane, and can also be coated on the side facing the lithium sulfide positive electrode when the battery is assembled. According to the lithium-sulfur battery disclosed by the invention, the dissolution of the sulfur positive electrode can be effectively prevented, the shuttle effect is inhibited, the overpotential of the battery is reduced, the structural damage generated by positive electrode volume expansion is avoided, and the rate characteristic and cycle performance of the lithium-sulfur battery are substantially improved.

The present invention provides a method of efficiently producing a lithium ion conductive inorganic solid electrolyte having high ionic conductivity, including: conducting a melt reaction of lithium sulfide containing 0.15 mass % or less of each of a lithium salt of sulfur oxide and lithium N-methylaminobutyrate, and one or more components selected from diphosphorus pentasulfide, elemental phosphorus, and elemental sulfur; rapidly cooling the resultant; and subjecting the resultant to heat treatment, and a high-performance lithium battery using the electrolyte. In particular, the present invention provides a high-performance lithium battery having high energy density, which is obtained by using a positive electrode active material having an operating potential of 3 V or more, a negative electrode active material having a reduction potential of 0.5 V or less, and a lithium ion conductive inorganic solid electrolyte in contact with at least the negative electrode active material, the lithium ion conductive inorganic solid electrolyte being produced from lithium sulfide and one or more components selected from diphosphorus pentasulfide, elemental phosphorus, and elemental sulfur, and which can be used as a monolayer.

The invention discloses a metal monoatom-doped carbon nanomaterial catalytic carrier, and a preparation method and application thereof. The metal monoatom-doped carbon nanomaterial catalytic carrier comprises a nitrogen-containing carbonaceous core-shell structure formed by coating a carbonaceous core with a nitrogen-containing carbon shell and metal monoatoms distributed in the nitrogen-containing carbonaceous core-shell structure. The metal monoatom-doped carbon nanomaterial catalytic carrier provided by the invention has rich porous structures, a high specific surface area, strong polysulfide ion adsorption capacity and an electrochemical catalysis function. When the metal monoatom-doped carbon nanomaterial catalytic carrier is applied as a lithium sulfide positive-electrode carrier, asecondary battery is allowed to achieve rapid activation (0.1 C) at a low cut-off voltage (3 V); an electrode structure can ensure the structural stability of the nanomaterial during electrochemical cycles, and high and prominent electrochemical cycle stability is obtained; the utilization rate of the active material of the battery is significantly improved; the overall electrochemical performanceof the battery is greatly improved; and the battery can be quickly charged and discharged.

The invention provides a preparation method of a sulfide electrolyte material as shown in a formula (I). The preparation method comprises the steps of mixing lithium sulfide, phosphorus pentasulfide and an organic solution to obtain a mixed solution; stirring, centrifuging, filtering and drying the mixed solution sequentially to obtain an initial material; performing heat treatment on the initial material to obtain the sulfide electrolyte material as shown in the formula (I). In the preparation process of the sulfide electrolyte material, lithium sulfide and phosphorus pentasulfide are dissolved into an organic solvent and react to form a compound containing Li, P and S, the compound and the organic solvent form a crystalline state, and then centrifuging, filtering, drying and heat treatment processes are performed sequentially to obtain the sulfide electrolyte material, so that the preparation method of the sulfide electrolyte material, provided by the invention, is simple and easy to operate.

The invention provides a lithium ion battery and a negative pole piece thereof. The negative pole piece of the lithium ion battery comprises a negative pole current collector and a negative pole active material layer which is arranged on the negative pole current collector. The negative pole piece of the lithium ion plate is characterized by further comprising a hard carbon material layer which contains hard carbon and is arranged on the negative pole active material layer. The hard carbon material layer also contains lithium salt which has mixture of lithium carbonate, lithium sulfide, lithium carbonic ester, alkoxy lithium, lithium sulphonate and alkyl diester lithium. The lithium ion battery comprises a positive pole piece, a negative pole piece which adopts the negative pole piece of the lithium ion battery, an isolating membrane arranged between adjacent positive and negative pole pieces, and electrolyte. By utilizing the lithium ion battery and the negative pole piece, the low temperature performance and the safety performance of the battery are effectively improved, and the rate capability and the discharge efficiency of the lithium ion battery are improved, the service life of the lithium ion battery is prolonged.

The present application relates to a separation membrane and a lithium-sulfur battery including the same, and the separation membrane according to the present application prevents elution of lithium polysulfide in a cathode and suppresses growth of a lithium dendrite generated in an anode, and thus has an effect that a life-span and safety of the battery are improved.

The present invention provides a process for producing a lithium sulfide-carbon composite, the process comprising placing a mixture of lithium sulfide and a carbon material having a specific surface area of 60 m2 / g or more in an electrically-conductive mold in a non-oxidizing atmosphere, and applying a pulsed direct current to the mold while pressurizing the mixture in a non-oxidizing atmosphere, thereby subjecting the lithium sulfide and the carbon material to heating reaction; and a lithium sulfide-carbon composite obtained by this process, the composite having a carbon content of 15 to 70 weight %, and a tap density of 0.4 g / cm3 or more when the carbon content is 30 weight % or more, or a tap density of 0.5 g / cm3 or more when the carbon content is less than 30 weight %. The present invention can improve the electronic conductivity of lithium sulfide, which is expected to be put into practical use as a high-capacity positive electrode active material, so as to further enhance the performance of lithium sulfide as a positive electrode active material for lithium ion secondary batteries.

The invention provides a sulfide solid electrolyte based on oxygen doping. The sulfide solid electrolyte is prepared from the chemical ingredients, in percentage by mass: 36-60% of lithium sulfide orlithium selenide, 18-48% of phosphorus pentasulfide or phosphorus selenide, 1-23% of metal oxide or specific nonmetallic oxide and 8-37% of lithium chloride, lithium bromide or lithium iodide. The preparation method of the sulfide solid electrolyte mainly comprises the steps that the raw materials are sufficiently blended and subjected to tabletting, then placed in a quartz tube to be burned and sealed, the product is placed in a muffle furnace and heated to be 400-600 DEG C at a slow heating rate, the optimal heating rate is 0.3 DEG C / minute, heat preservation is conducted for 12-48 hours, and then the product is cooled to reach the room temperature; and the product is ground to be powder, and the sulfide solid electrolyte based on oxygen doping is prepared. The sulfide solid electrolyteis easy to prepare and high in repeatability, the prepared solid electrolyte has the high ionic conductivity and good stability to the air and positive and negative electrodes.

The invention discloses a preparation method of lithium sulfide powder. The preparation method comprises the following steps: (1) drying sulfur powder; (2) under inert atmosphere protection, mixing the dried sulfur powder with lithium hydride powder in a mole ratio of 1:(1-3), adding the obtained mixture into a sealed ball-milling tank, and carrying out ball-milling on the mixture for 1-24 h under the condition that the rotating speed is 100-500 r / min at room temperature; and (3) after the ball-milling reaction is completed, under inert atmosphere, taking the powder out of the ball-milling tank, so that the lithium sulfide powder is obtained. The preparation method of lithium sulfide powder disclosed by the invention has the characteristics of simple process, low cost, and easiness for industrialized production.

The invention relates to an MXene / lithium sulfide / carbon composite cathode material and a preparation method of the MXene / lithium sulfide / carbon composite cathode material. The method comprises the following steps: (1) etching an MAX phase powder with an acid, filtering, washing and drying to obtain an MXene nanometer material with a porous structure; (2) preparing a solution from lithium sulfate,proportionally mixing with a carbon material or a carbon precursor, preparing a carbon / lithium sulfate or carbon precursor / lithium sulfate composite material; (3) heating the carbon / lithium sulfate or carbon precursor / lithium sulfate composite material in the step (2) under the protective atmosphere, reducing the above composite material into a lithium sulfide / carbon material by means of thermalreduction; (4) mixing the MXene nanometer material with the porous structure obtained in the step (1) with the lithium sulfide / carbon in the step (3), and ball-milling to obtain the MXene / lithium sulfide / carbon composite cathode material. Compared with the prior art, the prepared MXene / lithium sulfide / carbon composite cathode material has the advantages of high electrical conductivity, high specific capacity, good cycle performance, good rate capability, simple preparation process and the like.

This invention provides lithium-based batteries that include one or more inorganic barrier layers disposed between the anode and the cathode. The inorganic barrier layer is a lithium-ion conductor and is non-permeable to lithium-containing compounds, such as lithium polysulfides or lithium dendrites. The inorganic barrier layer may be in direct contact with the anode or cathode, or electrically isolated from the anode and cathode. The principles disclosed herein solve the problem of maintaining electrical isolation of the anode and cathode, while providing efficient lithium-ion conduction without crossover of other lithium species that would otherwise limit the power performance of the battery.

The invention relates to the technical field of lithium-sulfur batteries, and aims to provide a diaphragm for lithium-sulfur batteries and a preparation method of lithium-sulfur batteries. The preparation method of the diaphragm for lithium-sulfur batteries comprises the following steps: respectively preparing a polyolefin fiber reinforced lithium ion exchange membrane containing metal sulfide and a poly-lithium sulfide solution, and mixing the polyolefin fiber reinforced lithium ion exchange membrane containing metal sulfide and the poly-lithium sulfide solution so as to obtain a metal sulfide containing & poly-lithium sulfide doped & polyolefin fiber reinforced diaphragm for lithium-ion batteries; and a lithium-sulfur battery comprises electrolyte, a cathode, an anode and the prepared diaphragm for lithium-sulfur batteries. The metal sulfide containing & polyolefin fiber reinforced lithium ion exchange membrane prepared according to the invention has an extremely low internal resistance, good chemical stability and thermal stability and excellent cycle characteristic; and the diaphragm is simple in manufacturing process and pollution-free, and high in safety and high reliability.

A positive electrode material for a lithium sulphur battery and a preparation method thereof, and the lithium sulphur battery are disclosed. The positive electrode material comprises activated carbon,carbon black, transition metal or a transition metal compound, and sublimed sulfur; and the transition metal compound is metal carbide, metal boride, metal nitride, metal phosphide, metal oxide or metal sulfide. The activated carbon is utilized as a main body of sulfur carrying; the carbon black can carry sulfur and can also strengthen the conductivity of the positive electrode material; and thetransition metal or the transition metal compound can play a fixation role in lithium polysulfide produced in an electrochemical reaction, inhibits the shuttle effect of polysulfide ions, and enablesthe cycle performance of the lithium sulphur battery to be improved. The positive electrode material for the lithium sulphur battery disclosed by the invention has the advantages of being simple and easy to obtain, easy to be prepared on a large scale, and the like, and the lithium sulphur battery with long circulation, high specific capacity and high specific energy can be obtained.

A composite cathode material used for a lithium-sulfur battery and having high-rate performance comprises a conductive agent, electrochemical active substances and a modifier, wherein the conductive agent adopts a mesoporous carbon material, the electrochemical active substances are dispersed in holes of the mesoporous carbon material, and the modifier is introduced in a chemical bonding manner to adjust the property of the holes, so that lithium ions freely pass to inhibit passing of polysulfide ions. According to the composite cathode material, by means of the characteristic of selective passing of ions, efficient immigration and moving out of the lithium ions in the cathode material can be guaranteed, meanwhile, lithium polysulfide is effectively inhibited from overflowing from the holes of the mesoporous carbon material in a charge-discharge process, and dissolution of lithium polysulfide in an electrolyte is inhibited. Therefore, the composite cathode material can have excellent high-rate performance and can effectively reduce influence of active substance loss as well as lithium cathode corrosion, fast capacity fading and the like caused by a shuttling effect because of lithium polysulfide dissolution, and the cycle performance of the lithium-sulfur battery is remarkably improved.

A process for the production of a lithium transition metal sulphide such as lithium iron sulphide, the process comprising reacting a transition metal sulphide with lithium sulphide in a solvent comprising a molten salt or a mixture of molten salts. Lithium transition metal sulphides obtained using this process are useful in the production of electrodes, in particular for rechargeable lithium batteries.

The invention relates to a lithium-sulfur battery composite positive electrode material and a preparation method thereof. The positive electrode material consists of following components by weight percent: 30-59.4% of a conductive agent with a mesoporous structure, 40-60% of sulfur and 0.1-10% of a modifying agent, wherein sulfur is dispersed into holes of the conductive agent, and the modifying agent is connected with the holes of the conductive agent through a chemical bonding manner. The preparation method comprises the steps of pouring sulfur into the conductive agent by adopting a molten suction method so as to obtain a conductive agent / sulfur composite material; and then modifying the obtained conductive agent / sulfur composite material to obtain the lithium-sulfur composite positive electrode material. According to the composite positive electrode material, not only can the good high-rate stability be realized, but also the loss of active substances and the influences of corrosion to a lithium negative electrode, rapid capacity fading and the like caused by the 'shuttle effect' due to dissolution of lithium sulfide can be effectively reduced, and the cycle performance of the lithium-sulfur battery can be obviously improved.

The invention discloses a lithium sulfide / carbon composite nanometer material and a preparation method and application thereof. In a relatively typical embodiment, the method comprises the steps of fully mixing lithium sulfate and a carbon material precursor or a carbon material, and performing thermal treatment, wherein the thermal treatment condition comprises a temperature rising rate of 1-20 DEG C per minute, a constant temperature of 600 to 1000 DEG C for 2-12 hours in an inert atmosphere; and natural cooling of the material to a room temperature to acquire the lithium sulfide / carbon composite material. The invention provides a process for synthesizing the lithium sulfide / carbon nanocomposite material by reducing lithium sulfate with carbon, the process is simple and easy to operate, is high in controllability and low in cost, the raw materials are low in price and easy to get, moreover, the obtained product is the lithium sulfide / carbon nanocomposite material which is uniformly dispersed, has good performance and is controllable in morphology, the lithium sulfide / carbon nanocomposite material comprises a one-dimensional nanometer fiber, a two-dimensional nanosheet and the like, and the lithium sulfide / carbon nanocomposite material is high in conductivity and can be widely applied to an electrochemical energy storage device such as a lithium-sulfur battery.

The invention relates to a composite electrode material for a lithium-sulfur battery anode and a preparation method thereof. The composite electrode material is composed of a carbon material and lithium sulfide. The electrode material takes the compound of lithium sulfide and the carbon material as the substrate, the carbonization reaction of a carbon-containing compound is utilized to generate a carbon layer on the substrate surface, the lithium sulfide is sealed and coated in the pore channels of carbon, and the mass fraction of lithium sulfide in the composite electrode material is 40%-89%. The lithium-sulfur battery anode material prepared by the method can effectively avoid dissolution and diffusion of polysulfides in a charge-discharge process, thereby improving the cyclic stability and capacity of the battery.

The invention relates to the preparation and application of a covalent organic skeleton / titanium carbide nano-sheet composite material, and belongs to the technical field of development and research of new energy materials. The Ti3C2 nano-sheets with single layer or few layers are mixed with organic monomer and solid catalyst and sealed in a vacuum quartz tube, and a covalent organic skeleton / Ti3C2 nano-sheet composite material is obtained by the ionothermal method. The covalent organic skeleton / Ti_3C_2 nanocomposite was coated on aluminum as working electrode after carrying sulfur, lithium metal is used as counter electrode and reference electrode, organic microporous membrane is used as separator, organic solution is used as electrolyte, and a button cell is assembled in the glove box filled with high purity argon. Compared with the prior art, the present invention can be used as a two-dimensional electrode material, is widely used in the energy field such as lithium sulfide batteryand the like, and has excellent charging / discharging performance.

The invention relates to a method for preparing a lithium carbide / lithium sulfide (Li2S) composite anode material of a lithium-sulfur battery by performing carbon thermal reduction on lithium sulfate (Li2SO4), and belongs to the technical field of lithium-sulfur batteries. The lithium carbide / lithium sulfide composite material is prepared by performing the carbon thermal reduction on a lithium sulfate-containing composite material serving as a precursor under a condition of inert atmosphere protection, and is applied to an anode of the lithium-sulfur battery. The lithium sulfide composite material preparation method disclosed by the invention is a novel method for in-situ synthesis of the anode material of the lithium-sulfur battery; and the prepared lithium carbide / lithium sulfide composite material is high in active substance dispersivity and stable in structure, and has the advantages of high specific capacity, excellent circulating and rate capability and the like when used as an anode material of the lithium-sulfur battery. The method is easy to operate, low in preparation cost and favorable for large-scale production.

The invention belongs to the technical field of lithium-sulfur batteries, and relates to a diaphragm with an electro-catalysis function and a preparation method and application thereof. The diaphragmis composed of a commercial polymer diaphragm matrix and an electrocatalytic function modification layer coating the surface of one side of the diaphragm matrix, the electrocatalytic function modification layer comprises a binder, a conductive agent and an electrocatalyst; the electrocatalyst is a three-dimensional porous compound composed of graphene and heteroatom doped MoS2. The three-dimensional porous structure constructed by the graphene can adsorb a large amount of lithium polysulfide dissolved in the electrolyte through physical action; the heteroatom-doped MoS2 has rich interface defects, polarity and electrocatalytic activity, can efficiently and chemically adsorb lithium polysulfide and catalyze electrochemical conversion of the lithium polysulfide, inhibits the shuttle effect of the lithium-sulfur battery, and improves the reversible capacity and the cycling stability of the high-sulfur-loading lithium-sulfur battery.