Summary:
A collaboration between researchers in the UCLA Department of Materials Science and Engineering and SRI International has developed a novel solid-state cooling system that allows for efficient heat transfer for small, mobile devices.
Background:
With the development of modern technologies, the need for efficient heat transfer and cooling systems to maintain stable temperatures has become increasingly necessary. The most common cooling systems consist of vapor-compression refrigeration systems which typically have a reported coefficient of performance (COP) of 2-4. However, the main disadvantages of these systems are that they are bulky and have circulating liquids/parts, which make them undesirable for small, mobile devices. To address these issues, there has been increased interest in developing efficient solid-state cooling systems, which are typically smaller, but are costlier and less efficient. Currently developed solid state cooling systems based on the Peltier effect, the conversion of temperature differences to voltage, report COPs that are much lower than the vapor-compression refrigeration systems. Improvements in the solid-state cooling systems are necessary to be applied to rapidly advancing technology.
Innovation:
Dr. Pei and collaborators have developed a novel solid-state cooling system based on the electrocaloric (EC) effect, a reversible temperature change that occurs under an applied electric field, that employs an electrostatic actuator for effective thermal management. This system uses a flexible EC polymer stack and an electrostatic actuation mechanism to transfer heat. The researchers have demonstrated that this system can achieve a COP of 13, which is significantly higher than currently used vapor-compression refrigeration systems. Furthermore, this system can achieve a specific cooling power of 2.8 W/g, the highest reported value of any solid-state refrigeration to date.
Credit: Pei Group @ UCLA
Potential Applications:
Thermal management of various electronic devices.
Advantages:
- Higher COP compared to vapor-compression refrigeration systems
- Higher specific cooling power than current solid-state refrigeration systems to date
- Flexible, small size for nonconventional or mobile devices
- Lower cost compared to ceramic materials used in other solid-state cooling systems
State of Development:
System developed and manuscript is in preparation for submission.
Publications:
Highly efficient electrocaloric cooling with electrostatic actuation