Process for producing a lithium ion battery having the features a. it comprises a metallic housing enclosing an interior space and b. it comprises a composite body which is arranged in the interior space and is made up of at least one positive electrode , at least one negative electrode and at least one separator , wherein the electrodes are configured so as to be able to incorporate and release lithium ions reversibly, and also the additional features c. the housing comprises a cup-shaped first housing part and a second housing part , d. the cup-shaped first housing part comprises a circular or oval bottom , e. the cup-shaped first housing part comprises a ring-shaped side wall , f. the bottom and the side wall of the cup-shaped first housing part each have an inside facing the interior space and an outside facing in the opposite direction, and g. the composite body comprises a current conductor which electrically connects the at least one positive electrode or the at least one negative electrode to the cup-shaped first housing part, wherein the process comprises, in any order, the steps h. establishment of an electrical connection between the current conductor and the cup-shaped first housing part , and i. assembly of the first housing part and the second housing part to form the housing of the battery with inclusion of the composite body in the interior space , and before the steps g. and h. j. at least one of the specified insides of the cup-shaped first housing part is provided in its entirety or in regions with a coating composed of aluminium, chromium, tin or an alloy of these elements by means of sputter deposition. a. it comprises a metallic housing enclosing an interior space and b. it comprises a composite body which is arranged in the interior space and is made up of at least one positive electrode , at least one negative electrode and at least one separator , wherein the electrodes are configured so as to be able to incorporate and release lithium ions reversibly, and also the additional features c. the housing comprises a cup-shaped first housing part and a second housing part , d. the cup-shaped first housing part comprises a circular or oval bottom , e. the cup-shaped first housing part comprises a ring-shaped side wall , f. the bottom and the side wall of the cup-shaped first housing part each have an inside facing the interior space and an outside facing in the opposite direction, and g. the composite body comprises a current conductor which electrically connects the at least one positive electrode or the at least one negative electrode to the cup-shaped first housing part, wherein the process comprises, in any order, the steps h. establishment of an electrical connection between the current conductor and the cup-shaped first housing part , and i. assembly of the first housing part and the second housing part to form the housing of the battery with inclusion of the composite body in the interior space , and before the steps g. and h. j. at least one of the specified insides of the cup-shaped first housing part is provided in its entirety or in regions with a coating composed of aluminium, chromium, tin or an alloy of these elements by means of sputter deposition. <EOS>