A positive electrode active material is constituted by lithium transition metal-containing composite oxide particles having a layered rock salt type crystal structure and are composed of secondary particles each formed of an aggregation of primary particles. The secondary particles have a d50 of 3.0 to 7.0 μm, a BET specific surface area of 1.8 to 5.5 m.sup.2/g, a pore peak diameter of 0.01 to 0.30 μm, and a log differential pore volume [dV/d(log D)] of 0.2 to 0.6 ml/g within a range of the pore peak diameter. In each of a plurality of primary particles having a primary particle size of 0.1 to 1.0 μm, a coefficient of variation of the concentration of an additive element M is 1.5 or less.

A solid state high voltage battery includes a cathode; an anode; a catholyte solution in contact with the cathode; an anolyte solution in contact with the anode, and a separator disposed between the cathode and the anode. At least one of the catholyte or the anolyte is gelled, and at least one of the catholyte or the anolyte comprises an organic electrolyte, an ionic liquid electrolyte, or water in salt electrolyte.

Provided is encapsulated electroactive materials for use in rechargeable aqueous zinc cells, batteries, systems, and associated methods. A core-shell composite particle includes a core of electrochemically active material, and a shell of a polyelectrolyte matrix, substantially insoluble in water, yet allowing the transport of zinc cations to and from the electrochemically active core. A method for preparing the core-shell composite electrochemically active particle includes mechanically dispersing the electrochemically active material particles in association with the polyelectrolyte solution, insolubilizing the polyelectrolyte in the presence of the dispersed electrochemically active material particles, washing the encapsulated particles particle with water, and drying the washed encapsulated particles

A system and method for forming a metallic ion intercalated layered structure can include a housing, an electrolyte disposed in the housing, a counter-electrode disposed in the housing, and a working electrode disposed in the housing. The working electrode comprises a metallic support; and an electrode paste. The electrode paste can include an active material and a binder. The system can be used to form a layered structure having metallic ions from the metallic support intercalated into the layered structure based on cycling the working electrode.

A system and method for forming a metallic ion intercalated layered structure can include a housing, an electrolyte disposed in the housing, a counter-electrode disposed in the housing, and a working electrode disposed in the housing. The working electrode comprises a metallic support; and an electrode paste. The electrode paste can include an active material and a binder. The system can be used to form a layered structure having metallic ions from the metallic support intercalated into the layered structure based on cycling the working electrode.

Disclosed is a calcium salt, Ca(HMDS).sub.2, where HMDS is the hexamethyldisilazide anion (also known as bis(trimethylsilyl)amide), enables high current densities and high coulombic efficiency for calcium metal deposition and dissolution. These properties facilitate the use of this salt in batteries based on calcium metal. In addition, the salt is significant for batteries based on metal anodes, which have higher specific energies than batteries based on intercalation anodes, such as LiC.sub.6. In particular, a calcium based rechargeable battery includes Ca(HMDS).sub.2 salt and at least one solvent, the solvent suitable for calcium battery cycling. The at least one solvent can be diethyl ether, diisopropylether, methyl t-butyl ether (MTBE), 1,3-dioxane, 1,4-dioxane, tetrahydrofuran (THF), tetrahydropyran, glyme, diglyme, triglyme or tetraglyme, or any mixture thereof.

The present invention relates to a lithium secondary battery which includes a non-aqueous electrolyte solution including lithium bis(fluorosulfonyl)imide (LiFSI) and a fluorobiphenyl compound, a positive electrode including a lithium-nickel-manganese-cobalt-based oxide as a positive electrode active material, a negative electrode, and a separator.

The present invention relates to a lithium secondary battery which includes a non-aqueous electrolyte solution including lithium bis(fluorosulfonyl)imide (LiFSI) and a fluorobiphenyl compound, a positive electrode including a lithium-nickel-manganese-cobalt-based oxide as a positive electrode active material, a negative electrode, and a separator.

An electrochemical cell comprises a can comprising a cylindrical side wall extending from a closed end wall. The closed end wall comprises a protrusion. The protrusion has a protrusion cavity therein. A pre-formed pellet of a first electrode material is disposed in the protrusion cavity. The electrochemical cell may further comprise a separator defining an inner cavity and separating the inner cavity from an outer cavity. The outer cavity is defined by the can and the separator. The electrochemical cell may further comprise a first electrode material disposed in the outer cavity; and a second electrode material disposed in the inner cavity.

An electrochemical cell comprises a can comprising a cylindrical side wall extending from a closed end wall. The closed end wall comprises a protrusion. The protrusion has a protrusion cavity therein. A pre-formed pellet of a first electrode material is disposed in the protrusion cavity. The electrochemical cell may further comprise a separator defining an inner cavity and separating the inner cavity from an outer cavity. The outer cavity is defined by the can and the separator. The electrochemical cell may further comprise a first electrode material disposed in the outer cavity; and a second electrode material disposed in the inner cavity.