Flexible Electrocaloric Polymer Stack Driven by One AA Battery for Highly Efficient Personalized Thermoregulation

The electrocaloric (EC) effect holds irresistible attraction for personalized thermoregulation, since it can actively optimize bidirectional individual thermophysiological comfort with ultralow energy consumption. However, the practical application of EC polymer-based personalized thermoregulation has been severely limited by its high driving voltage. Here, a multilayer EC polymer stack with a layer thickness of 1 μm is constructed, realizing an observable adiabatic temperature change (Δ<i>T</i>) under safe driving voltage. The practicality of this EC polymer stack has been consolidated by driving two EC polymer stacks with one AA battery on the human hand. By analogy, 625 EC polymer stacks that are capable of covering the whole trunk of the human body with a Δ<i>T</i> of 4 K could be theoretically driven by only one AA battery. Featuring a low driving voltage, compact wearable design, and ultralow energy consumption, this active bidirectional multilayer EC polymer stack could partially bridge the gap between the EC effect and personalized thermoregulation.