Abstract: A battery is provided with an associated method for transporting metal-ions in the battery using a low temperature molten salt (LTMS). The battery comprises an anode, a cathode formed from a LTMS having a liquid phase at a temperature of less than 150° C., a current collector submerged in the LTMS, and a metal-ion permeable separator interposed between the LTMS and the anode. The method transports metal-ions from the separator to the current collector in response to the LTMS acting simultaneously as a cathode and an electrolyte. More explicitly, metal-ions are transported from the separator to the current collector by creating a liquid flow of LTMS interacting with the current collector and separator.

Abstract: 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.

Abstract: A system and method are presented for the large scale synthesis of metal cyanometallates (MCMs). First and second precursor solutions are added to a main reactor, where the first precursor includes M1 metal cations. The second precursor solution includes AX?M2(CN)Z?, where M1 and M2 are from a first group of metals and A is from a second group of metals including alkali or alkaline earth metals. In response to stirring the first and second precursors, MCM particles are formed with the formula AXM1NM2M(CN)Z.d[H2O]ZEO.e[H2O]BND, in solution. In response to aging in the secondary reactor, the size of the MCM particles is increases. The aged MCM particles in solution are then transferred to a separation tank, where the aged MCM particles are filtered from the solution and collected. The solution reclaimed from the separation tank back is added back into the main reactor.

Abstract: 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.

Abstract: A battery is provided with a hexacyanometallate cathode. The battery cathode is made from hexacyanometallate particles overlying a current collector. The hexacyanometallate particles have the chemical formula AXM1MM2N(CN)Z.d[H2O]ZEO.e[H2O]BND, where A is a metal from Groups 1A, 2A, or 3A of the Periodic Table, where M1 and M2 are each a metal with 2+ or 3+ valance positions, where “ZEO” and “BND” indicate zeolitic and bound water, respectively, where d is 0, and e is greater than 0 and less than 8. The anode material may primarily be a material such as hard carbon, soft carbon, oxides, sulfides, nitrides, silicon, metals, or combinations thereof. The electrolyte is non-aqueous. A method is also provided for fabricating hexacyanometallate with no zeolitic water content in response to dehydration annealing at a temperature of greater than 120 degrees C. and less than 200 degrees C.

Abstract: 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.

Abstract: A method is provided for fabricating a cyanometallate cathode battery. The method provides a cathode of AXM1YM2Z(CN)N.MH2O, where “A” is selected from a first group of metals, and where M1 and M2 are transition metals. The method provides an anode and a metal ion-permeable membrane separating the anode from the cathode. A third electrode is also provided including “B” metal ions selected from the first group of metals. Typically, the first group of metals includes alkali and alkaline metals. The method intercalates “B” metal ions from the third electrode to the anode, the cathode, or both the anode and cathode to form a completely fabricated battery. In one aspect, a solid electrolyte interface (SEI) layer including the “B” metal ions overlies a surface of the anode, the cathode, or both the anode and cathode. A cyanometallate cathode battery is also provided.

Abstract: An alkali/oxidant battery is provided with an associated method of creating battery capacity. The battery is made from an anode including a reduced first alkali metal such as lithium (Li), sodium (Na), and potassium (K), when the battery is charged. The battery's catholyte includes an element, in the battery charged state, such as nickel oxyhydroxide (NiOOH), manganese(IV) (oxide Mn( 4+)O2), or iron(III) oxyhydroxide Fe(3+)(OH)3), with the alkali metal hydroxide. An alkali metal ion permeable separator is interposed between the anolyte and the catholyte. For example, if the catholyte includes nickel(II) hydroxide (Ni(OH)2) in a battery discharged state, then it includes NiOOH in a battery charged state. To continue the example, the anolyte may include dissolved lithium ions (Li+) in a discharged state, with solid phase reduced Li formed on the anode in the battery charged state.

Abstract: A method is provided for charging a supercapacitor. The method initially provides a supercapacitor with a metal cyanometallate (MCM) particle anode, an electrolyte including a salt (DB) made up of cations (D+) anions (B?), and a cathode including carbonaceous materials (?). The method connects an external charging device between the anode and cathode, and the charging device supplies electrons to the anode and accepting electrons from the cathode. In response to the charging device, cations are inserted into the anode while anions are absorbed on the surface of the cathode. A supercapacitor device is also presented.

Abstract: A mechanism is presented for shielding a cathode in a metal cyanometallate battery. A battery is provided with an anode, a cathode, an electrolyte, and an ion-permeable membrane separating the anode from the cathode. The cathode is made up of a plurality of metal cyanometallate layers overlying the current collector. At least one of the metal cyanometallate layers is an active layer formed from an active material AXM1YM2Z(CN)N·MH2O, where “A” is an alkali metal, alkaline earth metal, or combination thereof. At least one of the metal cyanometallate layers is a shield layer comprising less than 50 percent by weight (wt %) active material. In response to applying an external voltage potential between the cathode and the anode, the method charges the battery. Upon discharge, the shield layer blocks metal particles from contacting active layers. Simultaneously, the shield layer transports metal ions from the electrolyte to the active layers.

Abstract: 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.

Abstract: A method is provided for forming a metal-ion battery electrode with large interstitial spacing. A working electrode with hexacyanometallate particles overlies a current collector. The hexacyanometallate particles have a chemical formula AmM1xM2y(CN)6.zH2O, and have a Prussian Blue hexacyanometallate crystal structure, where A is either alkali or alkaline-earth cations. M1 and M2 are metals with 2+ or 3+ valance positions. The working electrode is soaked in an organic first electrolyte including a salt including alkali or alkaline earth cations. A first electric field is created in the first electrolyte between the working electrode and a first counter electrode, causing A cations and water molecules to be simultaneously removed from interstitial spaces in the Prussian Blue hexacyanometallate crystal structure, forming hexacyanometallate particles having the chemical formula of Am?M1xM2y(CN)6.z?H2O, where m?<m and z?<z, overlying the working electrode.

Abstract: 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 pas tion 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.

Abstract: A method is provided for forming a metal-ion battery electrode with large interstitial spacing. A working electrode with hexacyanometallate particles overlies a current collector. The hexacyanometallate particles have a chemical formula AmM1xM2y(CN)6.zH2O, and have a Prussian Blue hexacyanometallate crystal structure, where A is either alkali or alkaline-earth cations. M1 and M2 are metals with 2+ or 3+ valance positions. The working electrode is soaked in an organic first electrolyte including a salt including alkali or alkaline earth cations. A first electric field is created in the first electrolyte between the working electrode and a first counter electrode, causing A cations and water molecules to be simultaneously removed from interstitial spaces in the Prussian Blue hexacyanometallate crystal structure, forming hexacyanometallate particles having the chemical formula of Am?M1xM2y(CN)6.z?H2O, where m?<m and z?<z, overlying the working electrode.

Abstract: 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.

Abstract: 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.

Abstract: A battery is provided with a hexacyanometallate cathode. The battery cathode is made from hexacyanometallate particles overlying a current collector. The hexacyanometallate particles have the chemical formula AXM1MM2N(CN)Z.d[H2O]ZEO.e[H2O]BND. where A is a metal from Groups 1A, 2A, or 3A of the Periodic Table, where M1 and M2 are each a metal with 2+ or 3+ valance positions, where “ZEO” and “BND” indicate zeolitic and bound water, respectively, where d is 0, and e is greater than 0 and less than 8. The anode material may primarily be a material such as hard carbon, soft carbon, oxides, sulfides, nitrides, silicon, metals, or combinations thereof. The electrolyte is non-aqueous. A method is also provided for fabricating hexacyanometallate with no zeolitic water content in response to dehydration annealing at a temperature of greater than 120 degrees C. and less than 200 degrees C.

Abstract: A supercapacitor is provided with a method for fabricating the supercapacitor. The method provides dried hexacyanometallate particles having a chemical formula AmM1xM2y(CN)6.pH2O with a Prussian Blue hexacyanometallate, crystal structure, where A is an alkali or alkaline-earth cation, and M1 and M2 are metals with 2+ or 3+ valance positions. The variable m is in the range of 0.5 to 2, x is in the range of 0.5 to 1.5, y is in the range of 0.5 to 1.5, and p is in the range of 0 to 6. The hexacyanometallate particles are mixed with a binder and electronic conductor powder, to form a cathode comprising AmM1xM2y(CN)6.pH2O. The method also forms an activated carbon anode and a membrane separating the cathode from the anode, permeable to A and A? cations. Finally, an electrolyte is added with a metal salt including A? cations. The electrolyte may be aqueous.

Abstract: 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.

Abstract: 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.