A thermal management system including: - a housing having a hollow interior , an inlet and an outlet for a fluid , and, disposed in said hollow interior : - a plurality of heat exchange and positioning devices , each comprising: -- a central body containing a material for storing thermal energy by latent heat accumulation, to be placed in thermal exchange with the fluid , and -- a structure for positioning the central body in said hollow interior , the positioning structure being connected to the central body around which it extends and reserving passages enabling contact between the central body and the surrounding fluid and a circulation of said fluid, characterized in that : - the positioning structure comprises an external structure defining a cylinder and connected by transverse arms to the central body , or - the positioning structure comprises an external structure defining a ring and connected by transverse arms to the central body , or - the positioning structure includes a peripheral structure extending circumferentially around the central body, in several planes, to separate it from a surrounding support in several directions, or - the positioning structure comprises an external structure : -- defining a discontinuous sphere , -- and connected to the central body by transverse arms around the central body , or - the positioning structure includes a cellular structure surrounding the central body , in contact with it, or - the positioning structure includes one or more linear beads surrounding the central body , in contact with it, or recesses formed in said body. - a housing having a hollow interior , an inlet and an outlet for a fluid , and, disposed in said hollow interior : - a plurality of heat exchange and positioning devices , each comprising: -- a central body containing a material for storing thermal energy by latent heat accumulation, to be placed in thermal exchange with the fluid , and -- a structure for positioning the central body in said hollow interior , the positioning structure being connected to the central body around which it extends and reserving passages enabling contact between the central body and the surrounding fluid and a circulation of said fluid, -- a central body containing a material for storing thermal energy by latent heat accumulation, to be placed in thermal exchange with the fluid , and -- a structure for positioning the central body in said hollow interior , the positioning structure being connected to the central body around which it extends and reserving passages enabling contact between the central body and the surrounding fluid and a circulation of said fluid, - the positioning structure comprises an external structure defining a cylinder and connected by transverse arms to the central body , or - the positioning structure comprises an external structure defining a ring and connected by transverse arms to the central body , or - the positioning structure includes a peripheral structure extending circumferentially around the central body, in several planes, to separate it from a surrounding support in several directions, or - the positioning structure comprises an external structure : -- defining a discontinuous sphere , -- and connected to the central body by transverse arms around the central body , or -- defining a discontinuous sphere , -- and connected to the central body by transverse arms around the central body , or - the positioning structure includes a cellular structure surrounding the central body , in contact with it, or - the positioning structure includes one or more linear beads surrounding the central body , in contact with it, or recesses formed in said body. <EOS>