US Patent 9634360 All-solid-state secondary cell

An all-solid-state secondary cell is provided comprising at least a positive electrode, a negative electrode and a solid electrolyte layer which is positioned between the positive electrode and the negative electrode. The positive electrode contains a positive electrode active material consisting of Na2Sx (x=1 to 8) and the solid electrolyte layer contains an ion conductive glass ceramics represented by a formula (I): Na2S-MxSy, wherein M is P, Si, Ge, B or Al; x and y each is an integer giving a stoichiometric ratio depending upon the type of M; and Na2S is contained in an amount of more than 67 mole % and less than 80 mole %.