Thermochemical Energy Storage of Concentrated Solar Power by Novel Y₂O₃-Doped CaO Pellets

Abstract

Reliable energy storage technology is a prerequisite for the efficient utilization of solar energy, among which thermochemical energy storage based on calcium looping emerges as a promising candidate. In this work, antisintering Y2O3 was doped into CaO to prepare a novel composite for energy storage. Benefiting from the homodispersity of Y2O3 in active CaO, which was proved by both scanning electron microscopy and transmission electron microscopy analyses, the novel composite exhibited high energy storage density and excellent cyclic stability. 35 wt % is considered as the optimal addition amount of Y2O3 because of its highest energy storage density of 1986 kJ/kg after 10 cycles. CaY35 not only showed outstanding extended cyclic performance but also maintained a satisfactory energy storage density of about 1400 kJ/kg under harsh calcination conditions due to its increased Brunauer–Emmett–Teller specific surface area and enriched porosity through the N2 adsorption analysis. In addition, the extrusion-spheronization method was employed to granulate CaY35 powders into spherical pellets. The extrusion force during the granulation process led to the destruction of the sorbent structure to some extent, resulting in a slight decline in pellet performance. However, the granulation endowed the pellets with excellent mechanical strengths and they lost only 4.28 wt % of their initial mass after 7000 rotations in a fragility tester, which was of great significance for their cyclic practical applications.

Review and Perspectives of the In Situ Modification Strategy for Bifunctional Electrodes in a Vanadium Redox Flow Battery

“…Following the Industrial Revolution, there was a notable surge in energy demand, − accompanied by a series of environmental challenges and energy-related issues. Dissatisfied with the constraints of traditional energy sources, − alternative energy sources, such as wind, nuclear, solar, and tidal energy, have been undergoing development. − While new energy sources can reduce greenhouse gas emissions to a certain extent and have the characteristics of continuous regeneration and perpetual use, they also face challenges, such as intermittency, instability, and susceptibility to natural conditions. − To address the requirements of modern living, researchers combined energy storage systems with renewable energy sources to enhance the stability of the power grid. − Among these solutions, redox flow battery devices stand out for their ability to convert and store electrical and chemical energy interchangeably, effectively addressing the intermittency challenge associated with renewable energy. In various electrochemical redox flow battery devices, the vanadium redox flow battery (VRFB) has garnered significant attention as a result of its cost-effectiveness, high level of stability, environment friendliness, and long service life. − …”

Thermodynamic and Structural Effects of Fe Doping in Magnesium Manganese Oxides for Thermochemical Energy Storage

“…A variety of TCES materials have been previously studied, including metallic hydrides, , hydroxides, carbonates, − and metal oxide materials. ,− The metal oxide materials are compatible with high-temperature power cycles and are operable in an open loop system, eliminating the reactant gas storage needed for the other systems . Mn 3 O 4 /Mn 2 O 3 was one of the earliest proposed metal oxide TCES systems because of its high reduction temperatures and its low cost and toxicity .…”

Effect of Mg/Al Oxides Supports on CaO Sorbents Prepared by Wet‐Mixing Synthesis for CO2 Capture

“…However, the main drawback of CaO-based sorbents is the decrease in CO 2 uptake capacity caused by sintering after repeated CO 2 capture/release cycles [10][11][12]. One of the approaches to reduce the sintering effect is to incorporate inert metal oxides with high Tammann temperatures, which act as structure stabilizers to improve the cyclic stability and maintain the reactivity of CaO sorbents during multicyclic reactions [13][14][15]. The metal oxides incorporated into Ca-based sorbents can be divided into two types according to their reactivity with CaO.…”