2745 results about "Lithium sulfur" patented technology

The present invention provides a battery or supercapacitor current collector which is prelithiated. The prelithiated current collector comprises: (a) an electrically conductive substrate having two opposed primary surfaces, and (b) a mixture layer of carbon (and / or other stabilizing element, such as B, Al, Ga, In, C, Si, Ge, Sn, Pb, As, Sb, Bi, Te, or a combination thereof) and lithium or lithium alloy coated on at least one of the primary surfaces, wherein lithium element is present in an amount of 1% to 99% by weight of the mixture layer. This current collector serves as an effective and safe lithium source for a wide variety of electrochemical energy storage cells, including the rechargeable lithium cell (e.g. lithium-metal, lithium-ion, lithium-sulfur, lithium-air, lithium-graphene, lithium-carbon, and lithium-carbon nanotube cell) and the lithium ion based supercapacitor cell (e.g, symmetric ultracapacitor, asymmetric ultracapacitor, hybrid supercapacitor-battery, or lithium-ion capacitor).

The invention is directed in a first aspect to a sulfur-carbon composite material comprising: (i) a bimodal porous carbon component containing therein a first mode of pores which are mesopores, and a second mode of pores which are micropores; and (ii) elemental sulfur contained in at least a portion of said micropores. The invention is also directed to the aforesaid sulfur-carbon composite as a layer on a current collector material; a lithium ion battery containing the sulfur-carbon composite in a cathode therein; as well as a method for preparing the sulfur-composite material.

Systems and methods for accurately determining the state of charge and the relative age of lithium sulfur batteries are provided. The cell resistance and taper input charge of a particular type of lithium sulfur battery are respectively measured to determine the state of charge and age of the battery.

Provided is an oriented multilayer porous film comprising at least one layer comprising: a heat, solvent, and degradation resistant matrix polymer; a plurality of interconnecting pores; and a porosity less than 90%. The film is made by a dry and / or wet method, with its multilayer structure constructed by coextrusion, lamination, and coating. The film of this disclosure finds a wide range of applications as a permselective medium for use in energy harvesting and storage, filtration, separation and purification of gases and fluids, CO2 and volatile capture, electronics, devices, structural supports, packaging, labeling, printing, clothing, drug delivery systems, bioreactor, and the like. The film is preferably used as a separator of lithium-ion, lithium-sulfur, lithium-air, metal-air, and nonaqueous electrolyte batteries.

A lithium-sulfur battery having a positive electrode including a positive active material including an active sulfur, where the positive electrode comprises an electron-conductive path and an ion-conductive path, and includes active pores of the average size of up to 20 μm having both electron-conductive and ion-conductive properties, and are filled with the active sulfur during an electrochemical reaction of the battery.

Disclosed is a method of charging a lithium-sulfur electrochemical cell wherein the lithium-sulfur cell comprises a cathode comprising an electroactive sulfur-containing material, an anode comprising lithium, and a nonaqueous electrolyte.

The invention discloses a method for preparing porous carbon@graphene composite material by taking a bimetal organic framework material as a precursor and application to modification of lithium-sulfur battery diaphragms thereof. The preparation method comprises the following steps: taking zinc salt and cobalt salt in a certain ratio as the raw materials, synthesizing a zinc / cobalt-bimetal organic framework@graphene composite material through a room-temperature liquid phase method, taking the zinc / cobalt-bimetal organic framework@graphene composite material as the precursor, carrying out high-temperature reaction under inert atmosphere, pickling and drying to obtain a cobalt / nitrogen double-doped porous carbon@graphene (Co-N-C@RGO) composite material. Co-N-C@RGO has high conductivity; the specific surface area of Co-N-C@RGO reaches up to 750-1000m<2> / g; the content of Co is 2-4At%; the content of N is 10-20At%. When the material is applied to the modification of the lithium-sulfur battery diaphragms, the material has the function of obviously inhibiting polysulfide shuttle effect and is capable of greatly improving actual specific capacity and cyclic performance of the lithium-sulfur batteries; meanwhile, the raw materials needed for synthesizing the material are simple; the operation is convenient; the large-scale production can be achieved; the material has certain promoting effect on commercialization of lithium-sulfur battery systems.

Disclosed is a method of charging a lithium-sulfur electrochemical cell wherein the lithium-sulfur cell comprises a cathode comprising an electroactive sulfur-containing material, an anode comprising lithium, and a nonaqueous electrolyte. Also disclosed are methods for determining charge termination when charging lithium-sulfur cells.

The invention discloses a lithium sulfur battery cathode material and a preparation method thereof. The lithium sulfur battery cathode material comprises a sulfur / graphene oxide compound, wherein a functional polymer layer and an adhesive layer sequentially cover on the sulfur / graphene oxide compound, and at least partial adhesive in the adhesive layer is crosslinked and combined with at least partial functional polymer material in the functional polymer layer. The preparation method of the lithium sulfur battery cathode material comprises the steps of: mixing powdered sulfur with graphene oxide, and carrying out high-temperature water heating on the mixture to form the sulfur / graphene oxide compound; then, packaging the sulfur / graphene oxide compound by the functional polymer material to obtain sulfur / graphene oxide electrode material covered by the functional polymer material; and mixing the sulfur / graphene oxide electrode material with the adhesive and the like, and carrying out high-temperature vacuum crosslinking reaction to obtain the target product. The lithium sulfur battery cathode material effectively improves the capacity and the cycle performance of an electrode; and the preparation technology of the lithium sulfur battery cathode material is simple and good in controllability, and meets the demand of large-scale production.

The invention provides a grapheme-coated sulfur / porous carbon composite material and a preparation method thereof, and relates to a grapheme-coated sulfur / porous carbon composite material used as the positive electrode material of a lithium-sulfur secondary battery and a preparation method thereof. The grapheme-coated sulfur / porous carbon composite positive electrode material provided by the invention can be used for solving the technical problem that the existing grapheme-coated sulfur-containing composite material used as the positive electrode material of a lithium-sulfur battery is low in electrochemical properties. The external surface of each of the particles of the grapheme-coated sulfur / porous carbon composite material provided by the invention is evenly covered with a graphene sheet, and a graphene conductive network is formed between the particles; the obtained grapheme-coated sulfur / porous carbon composite material has a hierarchical core-shell structure. The preparation method of the grapheme-coated sulfur / porous carbon composite material is obtained by adding a sulfur / porous carbon composite material to graphene slurry which is stable for a long time and in which graphene sheets are highly dispersed in water for mixing and coating. The positive electrode material has high specific capacity, long cycle life and excellent high-rate performance. Besides, the grapheme-coated sulfur / porous carbon composite material can be used as the positive electrode material of a lithium secondary battery.

An electrolyte solution for a lithium sulfur battery contains a lithium oxalatoborate compound in a 0.05-2 M solution in conventional lithium sulfur battery electrolyte solvents, optionally with other lithium compounds. Examples of solvents include dimethoxyethane (DME), dioxolane, and triethyleneglycol dimethyl ether (TEGDME). Electrochemical cells contain a lithium anode, a sulfur-containing cathode, and a non-aqueous electrolyte containing the lithium oxalatoborate compound. Lithium sulfur batteries contain a casing enclosing a plurality of the cells.

The invention discloses sulfenyl anode of a lithium-sulfur rechargeable battery and a preparation method thereof. The sulfenyl anode is prepared by the steps of: equally mixing sulfenyl compound active material, cyclodextrin binder and carbon conductivity agent, coating the mixture on an aluminum foil current collector and obtaining the sulfenyl anode after drying and pressing. The coating thickness is 50 to 100 microns and the aluminum foil thickness is 20 to 30 microns; the mass ratio of the sulfenyl compound active material, the cyclodextrin binder and the carbon conductivity agent is 7 to 8:0.6 to 1:0.6 to 1.5, wherein the sulfenyl compound active material is formed by the steps of: equally mixing carbon nano tube, sulfur and polyacrylonitrile according to the mass ratio of 0.1 to 0.2:6 to 8:1 and sintering the mixture in protection of inert gas at the temperature of 300 to 320 DEG C for insulation for 6 to 8 hours. By using the lithium-sulfur rechargeable battery with the sulfenyl anode and lithium metal cathode, the reversible capacity of the sulfenyl compound active material reaches 680mAh.g under 0.1C multiplying power charge-discharge condition; and compared with the discharge capacity of second circulation, the discharge capacity after 100 times of circulation decreases less than 10 percent.

The present invention discloses a preparation method of a complex lithium negative pole of a solid state battery, and belongs to the technical field of electrochemistry and new energy resources. The preparation method mainly comprises the steps: depositing lithium metal on three-dimensional carbon material or foam porous material gaps by using a heat infusing melting method or an electrodeposition method to obtain the complex lithium negative pole, wherein the application of a three-dimensional framework plays two roles, namely, providing adequate space for pre-storing lithium in the preparation process; providing a carrier for receiving metal lithium in a battery circulation process. The complex lithium negative pole can be widely applied in lithium metal batteries such as lithium ion batteries, lithium-air batteries, lithium-sulfur batteries, and solid state batteries. In the assembled symmetric solid state battery, under large electric current density of 5mA cm-2, a stable voltage decay (200mV) can still be kept after circulation for 100 times, in the battery circulation, the growth of lithium dendrites can be inhibited and the pole volume change can be stabilized, and the advantages of being good in circulation stability, and long service life can be realized; in the present invention, a carrier material is rich, and low in price; the process is controlled, the cost is low, and the batch production can be realized.

Electrode structures and electrochemical cells, including lithium-sulfur electrochemical cells, are provided. The electrode structures and / or electrochemical cells described herein may include one or more protective layers comprising a polymer layer and / or a gel polymer electrolyte layer. Methods for making electrode structures including such components are also provided.

Disclosed is a material which enhances stability for lithium in all the batteries, which use the lithium metal as an electrode material, by using and applying a lithium-substituted perfluoro sulfonic acid (PFSA) material in the form of a membrane or a powder to a lithium anode. Methods of manufacturing the material are also enclosed.

The invention discloses a lithium-sulfur battery multilayer composite positive electrode and a preparation method thereof, and belongs to the field of electrochemical batteries. The lithium-sulfur battery multilayer composite positive electrode has a multiple composite structure consisting of a first graphene thin-film layer, a carbon / sulfur active substance layer, a second graphene thin-film layer and a polymer layer, and multi-element integrated design of the lithium-sulfur batteries is realized. The positive electrode is characterized in that the performances of the lithium-sulfur battery are realized by integrally designing elements of the lithium-sulfur battery, the first graphene thin-film layer plays a role of a current collector, so that the weight of the current collector in the battery is effectively reduced and the effective contact between the current collector and an active electrode material is improved; and the second graphene thin-film layer and the polymer layer play a role of a diaphragm, are equivalent to a solid electrolysis layer and a barrier layer of a polysulfide, and are capable of effectively increasing transmission of electrons and ions and greatly limiting shuttling of polysulfide ions. The multilayer composite-structure positive electrode is simple and easily controllable in preparation process, can be prepared in large scale with low cost, and has great application value.

This patent application describes graphitic carbon nitride materials that are useful in electrochemical cells such as Lithium-Sulfur batteries. Also disclosed are lithium-sulfur batteries designed to incorporate these materials and methods of manufacturing the same. Batteries that include this material exhibit increased electrode kinetics of the lithium-sulfur electrochemical couple, phenomena that improve the specific capacity, usable lifetime and other desirable characteristics of these batteries.

The invention relates to a gel-type polymer electrolyte used for a lithium-sulfur secondary battery system, consisting of a polymer support body, an ionic liquid, an organic solvent, a mixed lithium salt and dioxide silicon particles. A preparation method comprises the following steps of: preparing an imidazolium-based ionic liquid, dioxide silicon and composite lithium salt into a gel liquid in a carbonic ester solution dissolved with macromolecular polymers, then coating, drying and obtaining the gel-type polymer electrolyte film. In the gel-type polymer electrolyte prepared by the invention, sulfides in the lithium-sulfur battery system can be effectively prevented from dissolving in a liquid electrolyte solution, the ionic conductivity is high, and noninflammability and no leakage are achieved; and for the polymer electrolyte, the preparation process is simple, and the raw material source is wide, so that the gel-type polymer electrolyte is suitable for industrial production.

An improved cathode suitable for lithium-sulfur batteries, a battery including the cathode, and a battery including a separator containing inorganic fillers are disclosed. The cathode includes sulfur and a metal oxide and optionally includes an additional polymeric material. The metal oxide reduces dissolution of sulfur at the cathode and reduces sulfur-containing deposits on the battery anode, thereby providing a battery with relatively high energy density and good partial discharge performance. The separator also reduces unwanted diffusion of sulfur species.

The invention relates to a pole piece of a positive electrode of a lithium-sulfur battery and a preparation method thereof. The pole piece takes gelatin as a binding agent to coat a positive electrode active material and a conductive additive on a current collector, thereby improving the adhesion and the dispersion of the electrode. Meanwhile, the pole piece of the positive electrode of the lithium-sulfur battery prepared by freeze-drying comprises a micro-porous structure, thereby reducing the infiltration resistance of electrolyte on the pole piece and improving the electrochemical reversibility and the cycle stability of the battery.

The invention relates to a carbon-sulfur composite material used for a positive pole of a lithium-sulfur battery. The carbon-sulfur composite material is characterized in that elemental sulfur is filled in a multi-hole hollow carbon ball which is synthesized through a simple template method, and the elemental sulfur is injected into the multi-hole hollow carbon ball by adopting a fusion diffused method; the carbon-sulfur composite material is used for preparing a positive pole material of a high-performance lithium-sulfur battery cell, the positive pole is composed of the carbon-sulfur composite material, a binding agent and an electric conduction agent, and polytetrafluoroethylene or polyvinylidene fluoride is used as the binding agent; and the electric conduction agent is a mixture of one or more than two of carbon nanometer fibre, electric conduction graphite, acetylene black and Super p in any proportion. The carbon-sulfur composite material provided by the invention has the advantages that compared with the reportorial lithium-sulfur secondary battery, the preparation method of the anode material is simple, the large specific capacity is 1450 Ahg-1, the coulomb efficiency is high and is greater than 99.0%, the cycle performance is good, the initial capacity is kept 93.6% after circulating for 50 weeks and the like, and the carbon-sulfur composite material is expected to be applied to the next generation large-scale stored energy batteries.

Embodiments presented herein provide a new approach for high-performance lithium-sulfur battery by using novel carbon-metal oxide-sulfur composites. The composites may be prepared by encapsulating sulfur particles in bifunctional carbon-supported metal oxide or other porous carbon-metal oxide composites. In this way, the porous carbon-metal oxide composite confines sulfur particles within its tunnels and maintain the electrical contact during cycling. Furthermore, the uniformly embedded metal oxides in the structure strongly adsorb polysulfide intermediates, avoid dissolution loss of sulfur, and ensure high coulombic efficiency as well as a long cycle life.

Systems and methods for accurately determining the state of charge and the relative age of lithium sulfur batteries are provided. The cell resistance and taper input charge of a particular type of lithium sulfur battery are respectively measured to determine the state of charge and age of the battery.

The invention discloses a graphene-based nitrogen-doped hierachical-pore carbon nanosheet / sulfur composite material for a cathode of a lithium sulfur battery, as well as a preparation method and application of the graphene-based nitrogen-doped hierachical-pore carbon nanosheet / sulfur composite material. The carbon nanosheet is a graphene-based nitrogen-doped hierachical-pore carbon nanosheet, and is prepared by the steps of growing poly-pyrrole on graphene oxide in situ, performing carbonization at high temperature, activating by using potassium hydroxide and forming pores, wherein the graphene oxide and nano-silicon dioxide serve as double templates; the thickness of the carbon nanosheet is 10 to 25 nm; the specific surface area is 800 to 1,600 m<2> / g; the pore diameter of the carbon nanosheet is distributed into the range of 0.8 to 6 nm in a concentrated way; the structure of the carbon nanosheet is a sandwich-like type which adopts graphene as the interlayer of the carbon nanosheet. The carbon nanosheet with abundant micro-pores, meso-pores and large specific surface area can load more sulfur active substances and can effectively inhibit dissolution of polysulfide. The ultrathin nanosheet, and the micro-pores and meso-pores guarantee diffusion of electrolyte and transmission of ions. According to the structure, the capacity, the cycling stability, the coulombic efficiency and the rate performance of the carbon nanosheet / sulfur composition material applied to the lithium sulfur battery are improved synergistically.

A rechargeable lithium-sulfur cell comprising a cathode, an anode, a separator electronically separating the two electrodes, a first electrolyte in contact with the cathode, and a second electrolyte in contact with the anode, wherein the first electrolyte contains a first concentration, C1, of a first lithium salt dissolved in a first solvent when the first electrolyte is brought in contact with the cathode, and the second electrolyte contains a second concentration, C2, of a second lithium salt dissolved in a second solvent when the second electrolyte is brought in contact with the anode, wherein C1 is less than C2. The cell exhibits an exceptionally high specific energy and a long cycle life.

Disclosed is an electrochemical cell comprising a lithium anode and a sulfur-containing cathode and a non-aqueous electrolyte. The cell exhibits high utilization of the electroactive sulfur-containing material of the cathode and a high charge-discharge efficiency.

A multi-electrode lithium-sulphur cell or battery including for example a negative electrode made of metal lithium, lithium alloys or lithium-absorbing materials; at least first and second distinct positive electrodes or groups of positive electrodes; and an electrolyte that is a solution of one or several salts in one or several solvents disposed between the negative and positive electrodes. The first positive electrode or group of positive electrodes is configured for charging, and the second positive electrode or group of positive electrodes is configured for discharging. The cell or battery has a high specific energy. Other embodiments of the present invention may include other structures and properties.

A solid electrolyte for a lithium-sulfur battery includes particles of a lithium ion conducting oxide composition embedded within a lithium ion conducting sulfide composition. The lithium ion conducting oxide composition can be Li7La3Zr2O12 (LLZO). The lithium ion conducting sulfide composition can be β-Li3PS4 (LPS). A lithium ion battery and a method of making a solid electrolyte for a lithium ion battery are also disclosed.

The invention relates to a carbon-sulfur-shell matter composite material having a network dual-core shell structure and a preparation method thereof. The carbon-sulfur-shell matter composite material has a carbon-sulfur-shell three layer structure, a central core (inner core) is nano carbon particles, sulfur elemental or a polysulfide containing-Sm-structure (m>2) is directly deposited on the nano carbon particles, or functional groups are introduced onto the nano carbon particles by use of polycyclic aromatic hydrocarbon like reaction capacity of the carbon material and through an irreversible chemical reaction, polymeric chains are introduced in, a crosslinked network structure is formed through stretching, bending and crosslinking of the polymeric chains on the surface of the nano carbon particles, the sulfur elemental or the polysulfide containing the-Sm-structure (m>2) is composited onto the crosslinked network structure to form a nano sulfur layer having a network structure, then a mono-core shell nano composite material having a network structure is obtained and is used as a second layer (outer core) of the carbon-sulfur-polymer composite material having the network dual-core shell structure, an outermost layer is a shell matter layer, electronic and / or ionic conductivity of the material are / is improved, dissolving loss of discharge products can be further inhibited, and structural stability of the material is improved. The material is suitable for positive poles of lithium sulfur batteries, and has a prominent effect on improvement of cycle stability of the lithium sulfur batteries.

A battery with a sulfur-containing cathode, an anode, and a separator between the cathode and the anode has a coating comprising a single-lithium ion conductor on at least one of the cathode or the separator.