Abstract: An anode-free rechargeable battery is disclosed. The battery includes an anode current collector and a cathode containing an active cation Mn+, where n=1, 2, or 3. The anode-free rechargeable battery further includes a separator placed between the anode current collector and the cathode. The anode-free rechargeable battery also includes an electrolyte including a salt or salt mixture containing an active cation Mn+ dissolved in a solvent or solvent mixture.

Abstract: Localized superconcentrated electrolytes (LSEs) for use in systems with silicon-based or carbon/silicon composite-based anodes are disclosed. The LSEs include an active salt, a nonaqueous solvent in which the active salt is soluble, and a diluent in which the active salt has a solubility at least 10 times less than solubility of the active salt in the nonaqueous solvent. Systems including the LSEs also are disclosed.

Abstract: Disclosed herein are embodiments of an electrolyte that is stable and efficient at high voltages. The electrolyte can be used in combination with certain cathodes that exhibit poor activity at such high voltages with other types of electrolytes and can further be used in combination with a variety of anodes. In some embodiments, the electrolyte can be used in battery systems comprising a lithium cobalt oxide cathode and lithium metal anodes, silicon anodes, silicon/graphite composite anodes, graphite anodes, and the like.

Abstract: Low flammability and nonflammable localized superconcentrated electrolytes (LSEs) for stable operation of lithium and sodium ion batteries are disclosed. Electrochemical devices including the low flammability and nonflammable LSEs are also disclosed. The low flammability and nonflammable LSEs include an active salt, a solvent comprising a flame retardant compound, wherein the active salt is soluble in the solvent, and a diluent in which the active salt is insoluble or poorly soluble. The LSE may further include a cosolvent, such as a carbonate, a sulfone, a sulfite, a sulfate, a carboxylate, an ether, a nitrogen-containing solvent, or any combination thereof. In certain embodiments, such as when the solvent and diluent are immiscible, the LSE further includes a bridge solvent.

Abstract: Embodiments of a safe, low-temperature reaction system and method for preparing porous silicon are disclosed. The porous silicon is prepared from porous silica, a low-melting metal halide, and a metal comprising aluminum, magnesium, or a combination thereof. Advantageously, embodiments of the disclosed methods can be performed at temperatures ?400° C. Silicon produced by the disclosed methods has a porosity that is equal to or greater than the porous silica precursor. The porous silicon is suitable for use in electrodes.

Abstract: Embodiments of a non-aqueous electrolyte for a rechargeable sodium (Na)-based battery comprise a sodium salt and a nonaqueous solvent, the electrolyte having a sodium salt concentration ?2.5 M or a solvent-sodium salt mole ratio ?4:1. Na-based rechargeable batteries including the electrolyte exhibit both high cycling stability and high coulombic efficiency (CE). Some embodiments of the disclosed batteries attain a CE?80% within 10-30 charge-discharge cycles and maintain a CE?80% for at least 100 charge-discharge cycles. In certain embodiments, the battery is an anode-free battery in the as-assembled initial state.

Abstract: Low flammability and nonflammable localized superconcentrated electrolytes (LSEs) for stable operation of electrochemical devices, such as rechargeable batteries, supercapacitors, and sensors, are disclosed. Electrochemical devices, such as rechargeable batteries, supercapacitors, and sensors, including the low flammability and nonflammable LSEs are also disclosed. The low flammability and nonflammable LSEs include an active salt, a solvent comprising a flame retardant compound, wherein the active salt is soluble in the solvent, and a diluent in which the active salt is insoluble or poorly soluble. In certain embodiments, such as when the solvent and diluent are immiscible, the LSE further includes a bridge solvent.

Abstract: Embodiments of localized superconcentrated electrolytes (LSEs) for stable operation of electrochemical devices, such as rechargeable batteries, supercapacitors, and sensors, are disclosed. Electrochemical devices, such as rechargeable batteries, supercapacitors, and sensors, including the LSEs are also disclosed. The LSEs include an active salt, a solvent in which the active salt is soluble, and a diluent in which the active salt is insoluble or poorly soluble. In certain embodiments, such as when the solvent and diluent are immiscible, the LSE further includes a bridge solvent.

Abstract: Embodiments of a safe, low-temperature reaction system and method for preparing porous silicon are disclosed. The porous silicon is prepared from porous silica, a low-melting metal halide, and a metal comprising aluminum, magnesium, or a combination thereof. Advantageously, embodiments of the disclosed methods can be performed at temperatures 400° C. Silicon produced by the disclosed methods has a porosity that is equal to or greater than the porous silica precursor. The porous silicon is suitable for use in electrodes.

Abstract: A solid-state lithium ion battery is disclosed. The battery includes an anode containing an anode active material. The battery also includes a cathode containing a cathode active material. The battery further includes a solid-state electrolyte material. The electrolyte material contains a salt or salt mixture with a melting point below approximately 300 degrees Celsius. The battery has an operating temperature of less than about 80 degrees Celsius.

Abstract: An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.

Abstract: An anode-free rechargeable battery is disclosed. The battery includes an anode current collector and a cathode containing an active cation Mn+, where n=1, 2, or 3. The anode-free rechargeable battery further includes a separator placed between the anode current collector and the cathode. The anode-free rechargeable battery also includes an electrolyte including a salt or salt mixture containing an active cation Mn+ dissolved in a solvent or solvent mixture.

Abstract: Embodiments of a method for cycling a rechargeable alkali metal battery with high Coulombic efficiency (CE) are disclosed. A slow charge/rapid discharge protocol is used in conjunction with a concentrated electrolyte to achieve high CE in rechargeable lithium and sodium batteries, include anode-free batteries. In some examples, the CE is ?99.8%.

Abstract: An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.

Abstract: Disclosed are preformed solid electrolyte interface (SEI) film graphite electrodes in lithium-sulfur based chemistry energy storage systems and methods of making the preformed SEI films on graphite electrodes to expand the use of graphite-based electrodes in previously non-graphite anode energy systems, such as lithium-sulfur battery systems. Also disclosed are lithium-ion sulfur battery systems comprising electrolytes that do not include an alkyl carbonate, such as those that do not include EC, and graphite anodes having preformed alkyl carbonate, such as EC-based SEI films.

Abstract: A solid-state lithium ion battery is disclosed. The battery includes an anode containing an anode active material. The battery also includes a cathode containing a cathode active material. The battery further includes a solid-state electrolyte material. The electrolyte material contains a salt or salt mixture with a melting point below approximately 300 degrees Celsius. The battery has an operating temperature of less than about 80 degrees Celsius.

Abstract: Embodiments of a non-aqueous electrolyte for a rechargeable sodium (Na)-based battery comprise a sodium salt and a nonaqueous solvent, the electrolyte having a sodium salt concentration ?2.5 M or a solvent-sodium salt mole ratio ?4:1. Na-based rechargeable batteries including the electrolyte exhibit both high cycling stability and high coulombic efficiency (CE). Some embodiments of the disclosed batteries attain a CE?80% within 10-30 charge-discharge cycles and maintain a CE?80% for at least 100 charge-discharge cycles. In certain embodiments, the battery is an anode-free battery in the as-assembled initial state.

Abstract: Methods for making composite anodes, such as macroporous composite anodes, are disclosed. Embodiments of the methods may include forming a tape from a slurry including a substrate metal precursor, an anode active material, a pore-forming agent, a binder, and a solvent. A laminated structure may be prepared from the tape and sintered to produce a porous structure, such as a macroporous structure. The macroporous structure may be heated to reduce a substrate metal precursor and/or anode active material. Macroporous composite anodes formed by some embodiments of the disclosed methods comprise a porous metal and an anode active material, wherein the anode active material is both externally and internally incorporated throughout and on the surface of the macroporous structure.

Abstract: The Coulombic efficiency of metal deposition/stripping can be improved while also preventing dendrite formation and growth by an improved electrolyte composition. The electrolyte composition also reduces the risk of flammability. The electrolyte composition includes a polymer and/or additives to form high quality SEI layers on the anode surface and to prevent further reactions between metal and electrolyte components. The electrolyte composition further includes additives to suppress dendrite growth during charge/discharge processes. The electrolyte composition can also be applied to lithium and other kinds of energy storage devices.

Abstract: Disclosed herein are embodiments of lithium/air batteries and methods of making and using the same. Certain embodiments are pouch-cell batteries encased within an oxygen-permeable membrane packaging material that is less than 2% of the total battery weight. Some embodiments include a hybrid air electrode comprising carbon and an ion insertion material, wherein the mass ratio of ion insertion material to carbon is 0.2 to 0.8. The air electrode may include hydrophobic, porous fibers. In particular embodiments, the air electrode is soaked with an electrolyte comprising one or more solvents including dimethyl ether, and the dimethyl ether subsequently is evacuated from the soaked electrode. In other embodiments, the electrolyte comprises 10-20% crown ether by weight.