A thermal management system comprising an electrochemical cell (100; 150; 1100) and a sheet for the thermal management and protection of the electrochemical cell (100; 150; 1100), the sheet comprising: a polymer matrix comprising two or more temperature management materials, characterized in that at least one of the two or more temperature management materials comprises: a microencapsulated phase change material, wherein the microcapsules implemented to contain the phase change material are formed as shells that define internal compartments within which the phase change material is positioned and have a spheroidal or spherical form and have sizes ranging from about 0,1 nm to 1000 microns, or polymeric phase change material , and wherein the phase change material has a latent heat of at least 5 Joules per gram and a transition temperature between 0°C and 100°C, and in that at least one other of the two or more temperature management materials comprises an elastomeric material, optionally a polymer elastomer, wherein the microencapsulated phase change material or the polymeric phase change material is dispersed within the elastomeric material, optionally within the polymer elastomer; and wherein the sheet is wrapped one or more times around an outer surface of the electrochemical cell (100; 150; 1100). a polymer matrix comprising two or more temperature management materials, characterized in that at least one of the two or more temperature management materials comprises: a microencapsulated phase change material, wherein the microcapsules implemented to contain the phase change material are formed as shells that define internal compartments within which the phase change material is positioned and have a spheroidal or spherical form and have sizes ranging from about 0,1 nm to 1000 microns, or polymeric phase change material , and wherein the phase change material has a latent heat of at least 5 Joules per gram and a transition temperature between 0°C and 100°C, and in that at least one other of the two or more temperature management materials comprises an elastomeric material, optionally a polymer elastomer, wherein the microencapsulated phase change material or the polymeric phase change material is dispersed within the elastomeric material, optionally within the polymer elastomer; and wherein the sheet is wrapped one or more times around an outer surface of the electrochemical cell (100; 150; 1100). a microencapsulated phase change material, wherein the microcapsules implemented to contain the phase change material are formed as shells that define internal compartments within which the phase change material is positioned and have a spheroidal or spherical form and have sizes ranging from about 0,1 nm to 1000 microns, or polymeric phase change material , and wherein the phase change material has a latent heat of at least 5 Joules per gram and a transition temperature between 0°C and 100°C, and in that at least one other of the two or more temperature management materials comprises an elastomeric material, optionally a polymer elastomer, wherein the microencapsulated phase change material or the polymeric phase change material is dispersed within the elastomeric material, optionally within the polymer elastomer; and wherein the sheet is wrapped one or more times around an outer surface of the electrochemical cell (100; 150; 1100). <EOS>