Abstract
This paper presents the design, fabrication, and characterization of a thermal oscillator driven by fixed DC voltages. The proposed device consists of a miniaturized ultra-sensitive temperature sensor and a microheater. The temperature sensor was fabricated by depositing acrylate-based temperature sensing material with a positive temperature coefficient (PTC) effect on an interdigital electrode pair, and this was the key component that enabled oscillations by periodically switching the microheater on and off. The acrylate-based material, which was prepared by dispersing an acrylate copolymer with graphite particles, exhibits an order-of-magnitude variation in resistivity over a temperature change of a few degrees. The transient behavior of the fabricated device was measured, and the effects on different driving conditions with active cooling were measured and discussed. In addition, the measurement results also show that the temperature drift is not obvious in long-term testing, which indicates that the acrylate composite is quite reliable during repeated phase transition.
Highlights
Studies on conductive polymer composites (CPCs) have received significant attention because of these composites’ potential applications in various industries [1,2,3,4,5]
The positive temperature coefficient (PTC) effect, which is a phenomenon found in many composite conductive polymers, was first observed in the carbon black-filled low-density polyethylene composite by Frydman [11] in 1945
One of the theories considered that the PTC effect is caused by the fact that the polymer matrix expands more than the conductive fillers as the temperature increases, and, subsequently, the compressive force on conductive fillers decreases
Summary
Studies on conductive polymer composites (CPCs) have received significant attention because of these composites’ potential applications in various industries [1,2,3,4,5]. PTC material was used as the additive on the electrodes of a lithium-ion battery for cutting off charge transportation paths in the vicinity of internal short sites before the local temperature of the battery reaches the onset of thermal runaway [21]. These aforementioned studies demonstrated various applications of PTC materials. The temperature sensor cuts off the supply current to the microheater when the resistance of the PTC composite increases significantly, which, in turn, produces the switching behaviors.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
