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Lu, Yuhao

Publications and source records attributed to Lu, Yuhao.

At least 19 records

Metal cyanometallates

Methods are presented for synthesizing metal cyanometallate (MCM). A first method provides a first solution of AXM2Y(CN)Z, to which a second solution including M1 is dropwise added. As a result, a precipitate is formed of ANM1PM2Q (CN)R.FH2O, where N is in the range of 1 to 4. A second method for synthesizing MCM provides a first solution of M2C(CN)B, which is dropwise added to a second solution including M1. As a result, a precipitate is formed of M1[M2S(CN)G]1/T.DH2O, where S/T is greater than or equal to 0.8. Low vacancy MCM materials are also presented.

36 MATERIALS SCIENCE↗

The Scale‐up and Commercialization of Nonaqueous Na‐Ion Battery Technologies

Abstract This report provides an overview of development activities that enable the scale‐up and thereby a pathway toward the commercialization of sodium‐ion battery technologies for the energy storage market. The electrochemical performance of active materials and full cell performance of batteries developed by two startup companies, Novasis Energies, Inc. and Faradion Limited, are discussed in detail. Both companies offer low‐cost sodium‐ion battery chemistries with uniquely developed active materials that afford high rate capability and cycling stability. Their technologies are highly scalable due to the implementation of abundant and predominantly nontoxic elements and the ability to utilize common battery fabrication and manufacturing equipment. Both companies utilize active materials that are cost competitive compared to low‐cost lithium‐ion battery materials while exhibiting very similar specific capacity. In addition, improved safety characteristics with respect to operation and transportation distinguish the described sodium‐ion batteries from their incumbent lithium‐ion counterparts. The featured technology is particularly attractive for large‐scale energy storage applications.

Bauer, Alexander↗

Modification of Transition-Metal Redox by Interstitial Water in Hexacyanometalate Electrodes for Sodium-Ion Batteries

A sodium-ion battery (SIB) solution is attractive for grid-scale electrical energy storage. Low-cost hexacyanometalate is a promising electrode material for SIBs because of its easy synthesis and open framework. Most hexacyanometalate-based SIBs work with aqueous electrolyte, and interstitial water in the material has been found to strongly affect the electrochemical profile, but the mechanism remains elusive. Here we provide a comparative study of the transition-metal redox in hexacyanometalate electrodes with and without interstitial water based on soft X-ray absorption spectroscopy and theoretical calculations. We found distinct transition-metal redox sequences in hydrated and anhydrated Na x MnFe(CN) 6 ·zH 2 O. The Fe and Mn redox in hydrated electrodes are separated and are at different potentials, leading to two voltage plateaus. On the contrary, mixed Fe and Mn redox in the same potential range is found in the anhydrated system. This work reveals for the first time how transition-metal redox in batteries is strongly affected by interstitial molecules that are seemingly spectators. The results suggest a fundamental mechanism based on three competing factors that determine the transition-metal redox potentials. Finally, because most hexacyanometalate electrodes contain water, this work directly reveals the mechanism of how interstitial molecules could define the electrochemical profile, especially for electrodes based on transition-metal redox with well-defined spin states.

25 ENERGY STORAGE↗

Battery electrode with metal particles and pyrolyzed coating

A method is provided for forming a metal battery electrode with a pyrolyzed coating. The method provides a metallorganic compound of metal (Me) and materials such as carbon (C), sulfur (S), nitrogen (N), oxygen (O), and combinations of the above-listed materials, expressed as MeXCYNZSXXOYY, where Me is a metal such as tin (Sn), antimony (Sb), or lead (Pb), or a metal alloy. The method heats the metallorganic compound, and as a result of the heating, decomposes materials in the metallorganic compound. In one aspect, decomposing the materials in the metallorganic compound includes forming a chemical reaction between the Me particles and the materials. An electrode is formed of Me particles coated by the materials. In another aspect, the Me particles coated with a material such as a carbide, a nitride, a sulfide, or combinations of the above-listed materials.

36 MATERIALS SCIENCE↗

Metal cyanometallate synthesis method

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.

36 MATERIALS SCIENCE↗

Anode for sodium-ion and potassium-ion batteries

A first method for fabricating an anode for use in sodium-ion and potassium-ion batteries includes mixing a conductive carbon material having a low surface area, a hard carbon material, and a binder material. A carbon-composite material is thus formed and coated on a conductive substrate. A second method for fabricating an anode for use in sodium-ion and potassium-ion batteries mixes a metal-containing material, a hard carbon material, and binder material. A carbon-composite material is thus formed and coated on a conductive substrate. A third method for fabricating an anode for use in sodium-ion and potassium-ion batteries provides a hard carbon material having a pyrolyzed polymer coating that is mixed with a binder material to form a carbon-composite material, which is coated on a conductive substrate. Descriptions of the anodes and batteries formed by the above-described methods are also provided.

25 ENERGY STORAGE↗

Hard carbon composite for alkali metal-ion batteries

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.

25 ENERGY STORAGE↗

Antimony-based anode on aluminum current collector

An electrochemical battery is provided with an aluminum anode current collector and an antimony (Sb)-based electrochemically active material overlying the aluminum current collector. The Sb-based electrochemically active material may be pure antimony, Sb with other metal elements, or Sb with non-metal elements. For example, the Sb-based electrochemically active material may be one of the following: Sb binary or ternary alloys of sodium, silicon, tin, germanium, bismuth, selenium, tellurium, thallium, aluminum, gold, cadmium, mercury, cesium, gallium, titanium, lead, carbon, and combinations thereof. The aluminum current collector may additionally include a material such as magnesium, iron, nickel, titanium, and combinations thereof. In one aspect, the anode further composed of a coating interposed between the aluminum current collector and the Sb-based electrochemically active material. This coating may be a non-corrodible metal or a carbonaceous material. The cathode is may be composed of a number of different active materials including sodium-based Prussian Blue analogs.

25 ENERGY STORAGE↗

Transition metal hexacyanometallate electrode with water-soluble binder

A method is provided for fabricating a transition metal hexacyanometallate (TMHCM) electrode with a water-soluble binder. The method initially forms an electrode mix slurry comprising TMHCF and a water-soluble binder. The electrode mix slurry is applied to a current collector, and then dehydrated to form an electrode. The electrode mix slurry may additionally comprise a carbon additive such as carbon black, carbon fiber, carbon nanotubes, graphite, or graphene. The electrode is typically formed with TMHCM greater than 50%, by weight, as compared to a combined weight of the TMHCM, carbon additive, and binder. Also provided are a TMHCM electrode made with a water-soluble binder and a battery having a TMHCM cathode that is made with a water-soluble binder.

Wang, Long↗

NASICON-polymer electrolyte structure

A method is provided for forming a sodium-containing particle electrolyte structure. The method provides sodium-containing particles (e.g., NASICON), dispersed in a liquid phase polymer, to form a polymer film with sodium-containing particles distributed in the polymer film. The liquid phase polymer is a result of dissolving the polymer in a solvent or melting the polymer in an extrusion process. In one aspect, the method forms a plurality of polymer film layers, where each polymer film layer includes sodium-containing particles. For example, the plurality of polymer film layers may form a stack having a top layer and a bottom layer, where with percentage of sodium-containing particles in the polymer film layers increasing from the bottom layer to the top layer. In another aspect, the sodium-containing particles are coated with a dopant. A sodium-containing particle electrolyte structure and a battery made using the sodium-containing particle electrolyte structure are also presented.

Wang, Long↗

Alkali-ion battery with enhanced transition metal cyanometallate electrode structure

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.

25 ENERGY STORAGE↗

Reactive separator for a metal-ion battery

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.

Wang, Long↗

Fabrication method for metal battery electrode with pyrolyzed coating

A method is provided for forming a metal battery electrode with a pyrolyzed coating. The method provides a metallorganic compound of metal (Me) and materials such as carbon (C), sulfur (S), nitrogen (N), oxygen (O), and combinations of the above-listed materials, expressed as MeXCYNZSXXOYY, where Me is a metal such as tin (Sn), antimony (Sb), or lead (Pb), or a metal alloy. The method heats the metallorganic compound, and as a result of the heating, decomposes materials in the metallorganic compound. In one aspect, decomposing the materials in the metallorganic compound includes forming a chemical reaction between the Me particles and the materials. An electrode is formed of Me particles coated by the materials. In another aspect, the Me particles coated with a material such as a carbide, a nitride, a sulfide, or combinations of the above-listed materials.

36 MATERIALS SCIENCE↗

Electrolyte additives for transition metal cyanometallate electrode stabilization

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.

25 ENERGY STORAGE↗

Battery with an anode preload with consumable metals

A method is provided for fabricating a battery using an anode preloaded with consumable metals. The method forms an ion-permeable membrane immersed in an electrolyte. A preloaded anode is immersed in the electrolyte, comprising MeaX, where X is a material such as carbon, metal capable of being alloyed with Me, intercalation oxides, electrochemically active organic compounds, and combinations of the above-listed materials. Me is a metal such as alkali metals, alkaline earth metals, and combinations of the above-listed metals. A cathode is also immersed in the electrolyte and separated from the preloaded anode by the ion-permeable membrane. The cathode comprises M1YM2Z(CN)N.MH2O. After a plurality of initial charge and discharge operations are preformed, an anode is formed comprising MebX overlying the current collector in a battery discharge state, where 0≦b<a.

Lu, Yuhao↗

Method for the synthesis of iron hexacyanoferrate

A method is provided for synthesizing iron hexacyanoferrate (FeHCF). The method forms a first solution of a ferrocyanide source [A4Fe(CN)6.PH2O] material dissolved in a first solvent, where “A” is an alkali metal ion. A second solution is formed of a Fe(II) source dissolved in a second solvent. A reducing agent is added and, optionally, an alkali metal salt. The first and second solutions may be purged with an inert gas. The second solution is combined with the first solution to form a third solution in a low oxygen environment. The third solution is agitated in a low oxygen environment, and AX+1Fe2(CN)6.ZH2O is formed, where X is in the range of 0 to 1. The method isolates the AX+1Fe2(CN)6.ZH2O from the third solution, and dries the AX+1Fe2(CN)6.ZH2O under vacuum at a temperature greater than 60 degrees C.

25 ENERGY STORAGE↗

Battery anode with preloaded metals

A method is presented for fabricating an anode preloaded with consumable metals. The method provides a material (X), which may be one of the following materials: carbon, metals able to be electrochemically alloyed with a metal (Me), intercalation oxides, electrochemically active organic compounds, and combinations of the above-listed materials. The method loads the metal (Me) into the material (X). Typically, Me is an alkali metal, alkaline earth metal, or a combination of the two. As a result, the method forms a preloaded anode comprising Me/X for use in a battery comprising a M1YM2Z(CN)N.MH2O cathode, where M1 and M2 are transition metals. The method loads the metal (Me) into the material (X) using physical (mechanical) mixing, a chemical reaction, or an electrochemical reaction. Also provided is preloaded anode, preloaded with consumable metals.

36 MATERIALS SCIENCE↗

Transition metal cyanometallate cathode battery with metal plating anode

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.

Lu, Yuhao↗