Thermoelectric-Powered Supercapacitors Based on Ni–Mn Nanowires Driven by Quadripartite Electrolyte

Abstract

Thermal energy is copiously available, especially low-grade heat which is typically wasted as a byproduct without use. Tapping into this immense energy reservoir with cost-effective technologies may become a key element for an energy-sustainable economy and society. The utilization of this waste thermal energy holds great potential in space applications for generating electric energy without using a solar panel. With this approach of harvesting heat energy, Ni−Mn composite nanowire-based electrodes synthesized via the electrochemical deposition technique are used to assemble a thermoelectric-powered supercapacitor. For charging purpose, the thermoelectric phenomenon of a quadripartite gel electrolyte [K 3 Fe(CN) 6 + K 4 Fe(CN) 6 + KOH + PVA] is tested. High-grade flexible copper tape used as a substrate can withstand high temperature and is perfectly suitable for thermoelectric devices. The fabricated symmetric device attained a high specific capacitance of 556 F/g at 4 mA in addition to a high energy density of 173.75 W h/kg at 3 kW/kg. Moreover, the fabricated thermoelectric-powered device attains a maximum voltage of ∼60 mV as a result of a temperature difference in the range of 8−10 °C. The proposed supercapacitor offers opportunities for the development of future devices that simultaneously harvest and store energy.

Advances in Ionic Thermoelectrics: From Materials to Devices

“…The signal in the low‐frequency region (close to the end of the abscissa) corresponds with the electronic impedance R e , and the signal in the high‐frequency region (close to the origin of the abscissa) is mainly related to the ionic impedance R i ( R e and R i can simultaneously exist in i‐TE systems). [ 113 ] The interpretations of Nyquist curves are based on the proper establishment of equivalent circuits. For instance, i‐TE materials can be sorted as three classes via the inserted Maxwell's equivalent fitting spectroscopy: [ 92,102,112 ] i) as shown in Figure 7a, the i‐TE polyelectrolyte PSSNa exhibits merely R i characteristics, where a specific spike appears at the low‐frequency region, ii) as shown in Figure 7b, complete electronic conductor PEDOT‐Tos exhibits merely R e characteristics, where all of the fitted points distributed at the high‐frequency region, iii) as shown in Figure 7c, PEDOT‐PSS exhibits both R i and R e characteristics, where a depressed semicircle at lower frequency and a segment of a macro semicircle within the higher frequency region can be observed from the fitting curve.…”

Alloy/Perovskite Compounds Modified by Plasma Treatment and their Role in Enhancing the Capacitance of Sustainable Graphene Supercapacitors

“…Despite such difficulties for SCs, they have been combined with other devices for advanced systems. For example, Verma et al [9] combined a SC and a thermoelectric device in one single system, which produced a high capacitance/energy-density of 556 F g À 1 / 173.75 Wh kg À 1 . When that device operates in "thermoelectric mode", it produces a voltage of 60 mV for a temperature gradient of 8-10 °C.…”

An Insight into the Wearable Technologies Based on Novel Hybrid Piezoelectric‐Triboelectric Nanogenerators

“…The wearable market readily manufactures and sells wearable devices that use novel HPTNGs. [14][15][16] These devices allow users to track their physical activity and performance in real time. In addition, the devices can communicate with other devices, such as smartphones, through near-field communication (NFC).…”