NOVELTY - The lithium-ion type battery (1) comprises a compartment (2) for housing the lithium electrochemical generator (3, 3', 3''), and a rigid flame retardant foam having closed porosity constituted of an electrically insulating material that fills the space between the inner wall of the compartment and the free surface of the sidewall of a container (4) of each generator. The foam covers the entire surface of the sidewall of the container on a specified length. The compartment comprises an inner wall matching the form of the side wall of the container.    USE - The battery is useful for lithium-ion type electrochemical generator, which is useful for electrical vehicles and in telecommunication industry.    ADVANTAGE - The battery provides excellent insulation and better thermal barrier effect against the spread of hot gases on the generator, allows the foam to prevent the spread of gas when they escape the bottom of the container, and provides fireproof properties, stiffness and tightness to the electrochemical generator and avoids damage due to elevated temperature.    DETAILED DESCRIPTION - The lithium-ion type battery (1) comprises a compartment (2) for housing the lithium electrochemical generator (3, 3', 3''), and a rigid flame retardant foam having closed porosity constituted of an electrically insulating material that fills the space between the inner wall of the compartment and the free surface of the sidewall of a container (4) of each generator. The foam covers the entire surface of the sidewall of the container on a specified length. The compartment comprises an inner wall matching the form of the side wall of the container, where the internal wall of the compartment is contacted with the sidewall of the container. The container has a cylindrical shape. The electrochemical generator comprises a container having an end blocked by a wall having a thinning to be torn by overpressure inside the container. The thinning has a circular shape. The foam further covers a closed end on a surface located outside the circular form. The electrochemical generator has a capacity of greater than 5 Ah. The electrically insulating material is made of a plastic material. The foam has a thermal conductivity of 0.02-0.2 W/mK and density of 5-800 kg/m3, and comprises a flame-retardant compound. The compartment comprises a flange comprising recesses to fit with a portion of the container of each of the generators and/or with a lid sealing the container of the generators, and an elastomer seal laid on the flange. The seal comprises openings contacting with the recesses of the flange. A first flange is fitted with a portion of the container of the generators, and a second flange is fitted with the lid of each of the generators.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic longitudinal view a section of a battery.    Battery (1)    Compartment (2)    Lithium electrochemical generators (3, 3', 3'')    Container (4)    Bottom of the compartment (5)    Top of the container. (6)