A cell cathode compartment comprises a granule bed comprising metal granules, metal halide granules, and sodium halide granules, a separator adjacent to the granule bed, a liquid electrolyte dispersed in the granule bed, and a porous absorbent disposed in the granule bed, wherein a transverse cross-sectional distribution of the porous absorbent in the granule bed varies in a longitudinal direction from a first position to a second position. In another embodiment, a cell cathode compartment comprises a granule bed comprising metal granules, metal halide granules, and sodium halide granules, a separator adjacent to the granule bed, a liquid electrolyte dispersed in the granule bed, and a porous absorbent coating on a surface adjacent to the granule bed.

A sodium molten salt battery includes a positive electrode containing a positive electrode active material, a negative electrode containing a negative electrode active material, a separator provided between the positive electrode and the negative electrode, and a molten salt electrolyte having sodium ion conductivity, in which the negative electrode active material contains hard carbon and is pre-doped with sodium ions, and in which when the state of charge is 0%, the potential of the negative electrode is 0.7 V or less with respect to metallic sodium.

A cathode composition is presented. The cathode composition includes an alkali metal halide and an electroactive metal. The electroactive metal includes a first population of particles that is present in a range at least about 50 weight percent of a total weight of the electroactive metal. A specific surface area of the first population of particles is lower than 0.2 m.sup.2/g. An electrochemical cell and an energy storage system including the cathode composition are also presented.

Molten lithium electrochemical cells are disclosed. A solid electrolyte separates a molten lithium metal or molten lithium metal alloy from a cathode. The molten lithium cells provide high Coulombic efficiency and energy efficiency at operating temperatures less than 600 C. The cells are useful for stationary energy storage in power grids.

Provided herein are energy storage devices. In some cases, the energy storage devices are capable of being transported on a vehicle and storing a large amount of energy. An energy storage device is provided comprising at least one liquid metal electrode, an energy storage capacity of at least about 1 MWh and a response time less than or equal to about 100 milliseconds (ms).

The present disclosure provides energy storage systems that can be manufactured with lower cost. The energy storage system may comprise a plurality of electrochemical cells, a rack placed in an enclosure to support the plurality of electrochemical cells, one or more panels between the rack and the enclosure to form one or more insulation sections, and insulation material disposed in the one or more insulation sections.

The present invention provides rechargeable electrochemical cells comprising a molten anode, a cathode, and a non-aqueous electrolyte salt, wherein the electrolyte salt is situated between the molten anode and the cathode during the operation of the electrochemical cell, and the molten anode comprises an aluminum material; also provided are batteries comprising a plurality of such rechargeable electrochemical cells and processes for manufacturing such rechargeable electrochemical cells.

Provided are a solid electrolyte for a sodium secondary battery, and a surface treatment method thereof, and more specifically, a solid electrolyte for a sodium secondary battery capable of having excellent electrochemical performance by improving wettability with respect to molten sodium, even under a low temperature operation environment of 250 C. or less, and a surface treatment method thereof.

A battery cell with a magnesium and beta alumina current collector includes a magnesium core with a beta alumina covering and bare magnesium collectors. The preferred embodiment uses a two chamber battery cell with a ceramic separator, where the cathode chamber contains the current collector and a compound of 38% common salt (NaCl) containing 80 micrograms of Iodine (I) per gram of common salt (NaCl), 18% Iron (Fe), 15% Zinc, (Zn), 16% Copper (Cu), 5% Nickel (Ni) and 4% Silver (Ag), and the anode chamber contains a compound of 38% common salt (NaCl) containing 80 micrograms of Iodine (I) per gram of common salt (NaCl).

A rechargeable electrochemical battery cell includes a molten carbonate salt electrolyte whose anion transports oxygen between a metal electrode and an air electrode on opposite sides of the electrolyte, where the molten salt electrolyte is retained inside voids of a porous electrolyte supporting structure sandwiched by the electrodes, and the molten salt includes carbonate including at least one of the alkaline carbonate including Li.sub.2Co.sub.2, NA.sub.2CO.sub.2, and K.sub.2CO.sub.2, having a melting point between 400 C. and 800 C.