The present disclosure relates to an electrolyte comprising: a) a sodium salt; b) an additive comprising at least one additional metallic/metalloid cation having a standard reduction potential which is at least 2.5V more positive than that of sodium cation; wherein said sodium salt and said additive are dispersed in a solvent comprising at least one alkyl carbonate, and wherein the concentration of said metallic/metalloid cation in the electrolyte is 15 mM to 250 mM. The present disclosure also relates to a sodium-sulfur cell comprising a sodium anode, a microporous sulfur cathode, and the electrolyte as described herein. The present disclosure further provides a method of improving cycling life of a sodium-sulfur cell, wherein the sodium-sulfur cell comprising a sodium anode, a sulfur cathode, and an electrolyte containing a sodium salt dispersed in an alkyl carbonate solvent.

A sodium-ion battery comprising a biochar-based anode layer, an NaNiO.sub.2 cathode layer, and an metakaolin solid electrolyte pellets layer.

Integrated energy storage system including a thermal energy storage coupled with a liquid metal battery storage and a cryogenic energy storage and related methods are described. An example integrated energy storage system includes a liquid metal battery storage, a cryogenic energy storage configured to store energy using a liquefied cryogen, a thermal energy storage, and a control system. The control system is configured to cause selective transfer of heat from the thermal energy storage to at least one battery unit associated with the liquid metal battery storage. The control system is configured to during a first mode associated with the cryogenic energy storage, cause selective transfer of heat from the cryogenic energy storage to the thermal energy storage. The control system is configured to during a second mode associated with the cryogenic energy storage, cause selective transfer of heat from the thermal energy storage to the cryogenic energy storage.

Integrated energy storage system including a thermal energy storage coupled with a liquid metal battery storage and a cryogenic energy storage and related methods are described. An example integrated energy storage system includes a liquid metal battery storage, a cryogenic energy storage configured to store energy using a liquefied cryogen, a thermal energy storage, and a control system. The control system is configured to cause selective transfer of heat from the thermal energy storage to at least one battery unit associated with the liquid metal battery storage. The control system is configured to during a first mode associated with the cryogenic energy storage, cause selective transfer of heat from the cryogenic energy storage to the thermal energy storage. The control system is configured to during a second mode associated with the cryogenic energy storage, cause selective transfer of heat from the thermal energy storage to the cryogenic energy storage.

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).

Performance of a thermal lithium battery is improved by improving the ion-transport characteristics of a solid lithium iodide electrolyte. The lithium iodide lattice of the solid electrolyte includes defects that improve the ion-transport characteristics of the solid lithium iodide electrolyte. In one example, the defects are due to the introduction of nanoparticles that result in grain boundary defects. The defects resulting at the grain boundaries with the nanoparticles improve the ion transport characteristics of the electrolyte. In another example, defects originating from the synthesis process are pinned by the presence of nanoparticles and/or the reinforcing structure. In another example, the defects are aliovalent substitution defects. A cation that is aliovalent to the lithium cation (Li.sup.+), such as a barium cation (Ba.sup.2+), creates an aliovalent substitution defect in the lithium iodide lattice. In order to maintain charge neutrality in the lattice, two lithium cations are replaced by a single barium cation creating the defect in the lattice.

Performance of a thermal lithium battery is improved by improving the ion-transport characteristics of a solid lithium iodide electrolyte. The lithium iodide lattice of the solid electrolyte includes defects that improve the ion-transport characteristics of the solid lithium iodide electrolyte. In one example, the defects are due to the introduction of nanoparticles that result in grain boundary defects. The defects resulting at the grain boundaries with the nanoparticles improve the ion transport characteristics of the electrolyte. In another example, defects originating from the synthesis process are pinned by the presence of nanoparticles and/or the reinforcing structure. In another example, the defects are aliovalent substitution defects. A cation that is aliovalent to the lithium cation (Li.sup.+), such as a barium cation (Ba.sup.2+), creates an aliovalent substitution defect in the lithium iodide lattice. In order to maintain charge neutrality in the lattice, two lithium cations are replaced by a single barium cation creating the defect in the lattice.

The invention relates to a method for manufacturing of a sinterable green body from sodium-β-aluminate- and/or precursor-particles bonded via binders by means of slip casting, wherein a castable slip containing the particles as well as dispersants and binders is introduced into a casting mold and, after solidification, is demolded as a green body.

The invention relates to a method for manufacturing of a sinterable green body from sodium-β-aluminate- and/or precursor-particles bonded via binders by means of slip casting, wherein a castable slip containing the particles as well as dispersants and binders is introduced into a casting mold and, after solidification, is demolded as a green body.

Provided is a technique with high strength, superior ionic conductivity, and superior electrical characteristics.

A lithium ion secondary battery includes a positive electrode, a negative electrode, and a polymer electrolyte. The polymer electrolyte contains a lithium salt, an ionic liquid, and a polymer. The ionic liquid contains a bis(fluorosulfonyl)imide anion as an anion component. The content of the lithium salt is 2 mol/kg or more and 6 mol/kg or less based on the sum of the content of the ionic liquid and the content of the polymer. The content of the polymer is 25% by mass or more and 40% by mass or less based on the sum of the content of the ionic liquid and the content of the polymer.