The present invention provides a battery, comprising a case, a cell packaged in the case, an electrical terminal located at one end of the case and electrically connected to the cell, a safety device and a current cut-off device. The safety device comprises a first and second electrode respectively electrically connected to a positive electrode or a negative electrode. The first electrode and the second electrode are arranged spaced apart from each other and form an electric field, and a gas generating material capable of generating an inert gas when a voltage reaches or exceeds a threshold value is provided in the electric field. The current cut-off device is electrically connected between the cell and the electrical terminal and is capable of causing a brake of circuit in response to a pressure difference between the inside and the outside of the battery caused by the inert gas.