Thermodynamic cycles requiring high operating temperatures (≥750 °C up to 1200 °C) are currently being explored to improve the sun-to-electricity conversion efficiency of Concentrating Solar Power (CSP) plants. This is calling for the design of new efficient high-temperature (≥750 °C) Thermochemical Energy Storage (TCES) systems, which are fundamental for supplying power on demand during off-sun periods. Recently, Fe-doped CaMnO3 oxides have been proposed as TCES candidate materials, and the determination of their thermodynamics properties via thermogravimetric (TG) analysis allowed evaluation of their heat storage capacity at a very small scale (mg scale). A 10 % Fe-doped CaMnO3 composition (CaMn0.9Fe0.1O3-δ – CMF91) emerged as optimum candidate material for TCES application due to its large heat storage capacity complemented by enhanced thermal stability over multiple oxidation/reduction cycles. To advance in the thermal characterization of these materials at a multigram scale, here we carried out bench-scale reactor tests using CMF91 under conditions considered representative of future CSP plants. The redox-active material has been extruded in the form of porous pellets through a simple production method that required the use of carboxymethylcellulose as a removable binder and water. With the bench-scale reactor tests, the CMF91 pellets showed fully reversible reduction-oxidation in cycles between 500 and 1100 °C under relevant operating pO2 conditions without any deterioration of the pellet's structural integrity. Remarkably, the material exhibited the same δ(T, pO2) profile at this significantly larger scale (~40 g) than the one derived from thermodynamics. Nevertheless, slight differences in oxygen release/uptake profiles between cooling and heating branches can be tracked down to an excess heat generation in the perovskite bed not efficiently extracted by the carrier gas. These results demonstrate that CMF91 oxide is ideally suited for thermal energy storage applications with a large total (thermochemical and sensible) heat storage capacity (~ 916 kJ/kgABO3 or ~ 400 kWh/m3) and good scalability. © 2022 This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska- Curie grant agreement N◦ 74616. Support of the ACES2030-CM from “Comunidad de Madrid” and European Structural Funds to (P2018/EMT-4319), and the Spanish “Ministerio de Economía y Competitividad” through Research Challenges project ARROPAR-CEX (ENE2015-71254-C3-1-R) are also fully acknowledged. M. S´anchez is grateful to Spanish “Ministerio de Economía y Competitividad” by funding through internship FPI (BES-2016-077031). It is greatly acknowledged the Technical Research Support Unit of the Institute of Catalysis and Petroleum Chemistry (ICP-CSIC). The authors fully appreciate the advice provided by Prof. Pedro Avila and Dr. Raquel Portela from the SpeICat group of ICP-CSIC, about the procedure for pellets preparation. Supporting Information Peer reviewed