The present invention relates to a multilayer fluid heat exchanger container comprising a thermo-conductive sheet, said sheet comprising at least a first layer comprising a metal foil and at least a second layer comprising a biocompatible plastic material, a multilayer sheet for the fluid container and systems for heating or cooling a fluid comprising the container and a fluid heating or cooling device for receiving the container. The present invention further relates to methods for heating or cooling a fluid comprising the step of circulating a fluid through the container and a process for the manufacture of the fluid container.