摘要:
A method is provided for fabricating a graphene-doped, carbohydrate-derived hard carbon (G-HC) composite material for alkali metal-ion batteries. The method provides graphene oxide (GO) dispersed in an aqueous solution. A carbohydrate is dissolved into the aqueous solution and subsequently the water is removed to create a precipitate. In one aspect, the carbohydrate is sucrose. The precipitate is dehydrated and exposed to a thermal treatment of less than 1200 degrees C. to carbonize the carbohydrate. The result is the formation of a graphene-doped, carbohydrate-derived hard carbon (G-HC) composite. Typically, the G-HC composite is made up of graphene in the range of 0.1 and 20% by weight (wt %), and HC in the range of 80 to 99.9 wt %. The G-HC composite has a specific surface area of less than 10 square meters per gram (m2/g). A G-HC composite suitable for use in alkali metal-ion batteries electrodes is also provided.
摘要:
A method is provided for fabricating a graphene-doped, carbohydrate-derived hard carbon (G-HC) composite material for alkali metal-ion batteries. The method provides graphene oxide (GO) dispersed in an aqueous solution. A carbohydrate is dissolved into the aqueous solution and subsequently the water is removed to create a precipitate. In one aspect, the carbohydrate is sucrose. The precipitate is dehydrated and exposed to a thermal treatment of less than 1200 degrees C. to carbonize the carbohydrate. The result is the formation of a graphene-doped, carbohydrate-derived hard carbon (G-HC) composite. Typically, the G-HC composite is made up of graphene in the range of 0.1 and 20% by weight (wt %), and HC in the range of 80 to 99.9 wt %. The G-HC composite has a specific surface area of less than 10 square meters per gram (m2/g). A G-HC composite suitable for use in alkali metal-ion batteries electrodes is also provided.
摘要:
An alkali-ion battery is provided with a transition metal cyanometallate (TMCM) sheet cathode and a non-alkaline metal anode. The fabrication method mixes TMCM powders, conductive additives, and a polytetrafluoroethylene binder with a solution containing water, forming a wet paste. The wet paste is formed into a free-standing sheet of cathode active material, which is laminated to a cathode current collector, forming a cathode electrode. The free-standing sheet of cathode active material has a thickness typically in the range of 100 microns to 2 millimeters. The cathode electrode is assembled with a non-alkaline metal anode electrode and an ion-permeable membrane interposed between the cathode electrode and anode electrode, forming an assembly. The assembly is dried at a temperature of greater than 100 degrees C. The dried assembly is then inserted into a container (case) and electrolyte is added. Thick anodes made from free-standing sheets of active material can be similarly formed.
摘要:
A reactive separator is provided for a metal-ion battery. The reactive separator is made up of a reactive layer that is chemically reactive to alkali or alkaline earth metals, and has a first side and a second side. A first non-reactive layer, chemically non-reactive with alkali or alkaline earth metals, is adjacent to the reactive layer first side. A second non-reactive layer, also chemically non-reactive with alkali or alkaline earth metals, is adjacent to the reactive layer second side. More explicitly, the first and second non-reactive layers are defined as having less than 5 percent by weight (wt %) of materials able to participate in electrochemical reactions with alkali or alkaline earth metals. The reactive layer may be formed as a porous membrane embedded with reactive components, where the porous membrane is carbon or a porous polymer. Alternatively, the reactive layer is formed as a polymer gel embedded with reactive components.
摘要:
A battery structure is provided for making alkali ion and alkaline-earth ion batteries. The battery has a hexacyanometallate cathode, a non-metal anode, and non-aqueous electrolyte. A method is provided for forming the hexacyanometallate battery cathode and non-metal battery anode prior to the battery assembly. The cathode includes hexacyanometallate particles overlying a current collector. The hexacyanometallate particles have the chemical formula A′n′AmM1xM2y(CN)6, and have a Prussian Blue hexacyanometallate crystal structure.
摘要:
A transition metal hexacyanoferrate (TMH) cathode battery is provided. The battery has a AxMn[Fe(CN)6]y.zH2O cathode, where the A cations are either alkali or alkaline-earth cations, such as sodium or potassium, where x is in the range of 1 to 2, where y is in the range of 0.5 to 1, and where z is in the range of 0 to 3.5. The AxMn[Fe(CN)6]y.zH2O has a rhombohedral crystal structure with Mn2+/3+ and Fe2+/3+ having the same reduction/oxidation potential. The battery also has an electrolyte, and anode made of an A metal, an A composite, or a material that can host A atoms. The battery has a single plateau charging curve, where a single plateau charging curve is defined as a constant charging voltage slope between 15% and 85% battery charge capacity. Fabrication methods are also provided.
摘要:
A protected transition metal hexacyanoferrate (TMHCF) battery cathode is presented, made from AxMyFez(CN)n.mH2O particles, where the A cations are either alkali or alkaline-earth cations, and M is a transition metal. In one aspect the cathode passivation layer may be materials such as oxides, simple salts, carbonaceous materials, or polymers that form a film overlying the AxMyFez(CN)n.mH2O particles. In another aspect, the cathode passivation layer is a material such as oxygen, nitrogen, sulfur, fluorine, chlorine, or iodine that interacts with the AxMyFez(CN)n.mH2O particles, to cure defects in the AxMyFez(CN)n.mH2O crystal lattice structure. Also presented are TMHCF battery synthesis methods.
摘要:
A method is provided for synthesizing metal cyanometallate (MCM). The method provides a solution of AXM1Y(CN)Z; where “A” is selected from a first group of metals and M1 is selected from a second group of metals. The method adds a material including M2 to the solution to form a liquid phase material that may be either a suspension or a solution. M2 is selected from the second group of metals. The method adds acid to the liquid phase material. The addition of acid to the liquid phase material decomposes the M2 material into M2-ions. Simultaneous with the addition of the acid, a precipitate of ANM1PM2Q(CN)R.FH2O is formed, where N is in a range of 1 to 2. A variation of the above-described synthesis method is also provided.
摘要:
A method is provided for the self-repair of a transition metal cyanometallate (TMCM) battery electrode. The battery is made from a TMCM cathode, an anode, and an electrolyte including solution formed from a solvent and an alkali or alkaline earth salt. The electrolyte includes an additive represented as G-R-g: where G and g are independently include materials with nitrogen (N) sulfur (S), oxygen (O), or combinations of the above-recited elements; and where R is an alkene or alkane group. In response to charging and discharging the battery in a plurality of cycles, the method creates vacancies in a surface of the TMCM cathode. Then, the method fills the vacancies in the surface of the TMCM cathode with the electrolyte additive. An electrolyte and TMCM battery using the above-mentioned additives are also provided.
摘要:
A method is provided for cycling power in a transition metal cyanometallate (TMCM) cathode battery. The method provides a battery with a TMCM cathode, an anode, and an electrolyte, where TMCM corresponds to the chemical formula of AXM1NM2M(CN)Y-d(H2O), where “A” is an alkali or alkaline earth metal, and where M1 and M2 are transition metals. The method charges the battery using a first charging current, or greater. In response to the charging current, a plating of “A” metal is formed overlying a plating surface of the anode. In response to discharging the battery, the “A” metal plating is removed from the anode plating surface. In one aspect, in an initial charging of the battery, a permanent solid electrolyte interphase (SEI) layer is formed overlying the anode plating surface. In subsequent charging and discharging cycles, the permanent SEI layer is maintained overlying the anode plating surface.