Abstract: The present invention relates to a battery comprising: -i) at least two electrochemical elements (d) connected to one another by a connection part (c), each electrochemical element comprising a container, -ii) a material arranged between said at least two electrochemical elements, and -iii) at least one disconnection device, said device comprising: a heat-activatable element (a) able to deform when its temperature reaches a threshold value, the heat-activatable element being arranged such that, when its temperature QI reaches said threshold value, it disconnects the connection part (c) from at least one electrochemical element (d) through its deformation, said heat-activatable element not contributing to the conduction of electric current when an electric current flows through said electro-chemical elements, said heat-activatable element being placed in contact with the connection part (c) and with a current output terminal.