Abstract: An all-solid secondary battery includes: a cathode layer including a cathode active material; an anode layer including an anode current collector, a first anode active material layer, and a second anode active material layer between the anode current collector and the first anode active material layer; and a solid electrolyte layer between the cathode layer and the anode layer and including a solid electrolyte, wherein the first anode active material layer is adjacent to the solid electrolyte layer, has pores, and contains a metal or metal alloy capable of forming an alloy or a compound with lithium, and the second anode active material layer includes a second anode active material including a carbon anode active material and optionally a metal or metalloid anode active material.

Abstract: A vent includes a gas inlet configured to allow gas to be introduced therethrough, a gas outlet configured to allow the gas introduced through the gas inlet to be discharged to the outside therethrough, an alarm means provided at one side of the gas outlet, the alarm means being configured to generate sound when the gas is discharged to the outside, a connection portion configured to connect the gas inlet and the gas outlet to each other, and a sealing cap located in the connection portion, the sealing cap being configured to automatically discharge gas to the outside, whereby gas generated in a battery cell or a battery module is automatically discharged to the outside.

Abstract: The solid electrolyte material of the present disclosure is a solid electrolyte material made of Li, Ca, Y, Gd, X, and O, where X is at least one selected from the group consisting of F, Cl, Br, and I; the molar ratio of O to the sum of Y and Gd in the entire solid electrolyte material is greater than 0 and 0.42 or less; and O is present in a surface region of the solid electrolyte material.