Reported by Yan Liu
In spite of the rising demand for energy, where the demand has increased by more than 40% over the last few decades, nearly 20-50%, and sometimes as high as 67%, of the overall energy generated by various devices, in manufacturing industries and in power plants is still wasted in the form of heat.
Working Principle and Performance of H+- Ion Concentration Thermal Battery
Recently, Prof. Yongning Liu in School of Materials Science and Engineering at Xi’an Jiaotong University, reported a new power generator that utilizes a difference in H+ ion concentration created in the cell and effectively produces electricity from waste heat. The thermoelectric conversion efficiency of the cell was calculated in cooperation with Professor Li Chen in the laboratory of Heat Flow Science and Engineering belonging to the Key Laboratory Ministry of Education at Xi'an Jiaotong University. The device works via the following successive processes: The H2 that is supplied at the anode makes it through the membrane in form of H+ ions and is harvested back at cathode. So, ultimately no H2 is consumed by the device, except heat, when the cell is producing electricity.
This system generates electricity at a current density of 21 mA cm−2 and a power density of 1.03 mW cm−2 at 170 °C. The cell's thermoelectric conversion efficiency at 170 °C is 13.72%, which is higher than typical values reported for many common thermoelectric materials in low temperature regimes. Based on the structural characteristics of fuel cell, the cell can also be formed by series connection to improve the output voltage and power. The research results provide a novel way for the utilization of heat energy.
This research was recently published in an international top journal, Nano Energy (IF=13.12), with the title of “Harvesting Waste Heat Energy by Promoting H+-Ion Concentration Difference with a Fuel Cell Structure”. This work is an interdisciplinary frontier involving materials science, electrochemistry as well as heat and mass transfer. Researchers from different directions have conducted in-depth cooperation. The first author of the paper is Yan Liu, a doctoral student at the School of Materials Science and Engineering. The corresponding author is Professor Yongning Liu. The co-authors include Professor Tewodros Asefa of Rutgers University and Professor Li Chen, Xi'an Jiaotong University is the first corresponding author Unit.
This work is supported by the National Natural Science Foundation of China and the Youth Science Foundation.
Professor Yongning Liu 's group has been exploring and doing investigations on energy materials and technologies such as lithium-ion battery materials, fuel cells and supercapacitors for many years. A number of research results have been published in Nano Letter, Nano Energy, Journal of Materials Chemistry A and other internationally top journals. H+- ion concentration thermal cell is a new kind of system invented on the basis of these research results, and it is an independent and original achievement.
Paper Link: https://doi.org/10.1016/j.nanoen.2018.12.022
