Energy transport inside a three-phase electrode and application to a proton-conducting solid oxide electrolysis cell

Abstract

This work focuses on the modelling of thermal processes inside a planar high temperature steam electrolyzer that use cermets as electrodes. While the continuity equation for mass and charge have been demonstrated in a previous publication, energy balance for thermal transfers inside the electrode assembly is established via a control volume method. A non-dimensional number is built from different criterion used in the literature in order to validate the local thermal equilibrium assumption (LTE) inside the porous electrodes. A parametric analysis is carried out on a proton-conducting solid oxide electrolysis cell in galvanostatic mode. The results show that the heat sources are mainly ohmic and that their locations are not dependent on inlet current and inlet velocity of gases. This observation allows us to build an original thermal resistance network in order to analytically evaluate the temperature inside each component of the cell. This modelling strategy reduces computation time, allows reverse physical analysis and gives a precise estimation on the maximum temperatures attained in the components of the cells.

Testing the Chemical/Structural Stability of Proton Conducting Perovskite Ceramic Membranes by in Situ/ex Situ Autoclave Raman Microscopy

“…In the second part of this manuscript, the diffraction, Raman, IR, TGA results obtained for four different proton conducting perovskite high dense ceramics: BaZr 0.9 Yb 0.1 O 3−δ (BZ:Yb), SrZr 0.9 Yb 0.1 O 3−δ (SZ:Yb), BaZr 0.25 In 0.75 O 3−δ (BZ:In) and BaCe 0.5 Zr 0.3 Y 0.16 Zn 0.04 O 3−δ (BCZ:Y,Zn) will be presented in order to compare their stability aspects. These perovskite compositions are widely studied by many academic and industrial groups up to the demonstrator scale [ 6 , 9 , 12 , 13 , 14 , 15 , 16 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. They appear promising candidates for various electrochemical applications where a combination of high conductivity and high stability is required.…”

Analytical evaluation of heat sources and electrical resistance of a cermet electrode for the production of hydrogen in a membrane reactor

“…The local equation for the conservation of thermal energy inside the electrode was established by our group [5,19] and is given s: …”

“…The electrochemical reaction occurs at the junction of these three phases, called the triple phase boundary (TPB). During the electrochemical process, transport of protons, electrons and chemical species occurs simultaneously in the reactor along with the corresponding heat sources which can cause a degradation of the assembly [5]. The experimental assessment of these coupled phenomena is difficult due to the hard operating conditions of the reactor (600e1000 C, 1e10 bars) and because of the complex microstructure of the electrode.…”

SNG based energy storage systems with subsurface CO2storage

“…Solid oxide electrolyser cells (SOEC) gained major attention in recent years. [50][51][52] Making use of a membrane electrode assembly (MEA) comprising dense ceramic electrolytes that can be either oxygen-anion or proton conducting as well as porous cermet electrodes, SOECs can produce wet or dry H 2 at temperatures between 500 1C and 1000 1C. [52][53][54] SOECs surpass todays commercialised electrolyser technologies such as AEL and PEM with respect to cell voltage, efficiency and specific power consumption (Table 1).…”

“…[50][51][52] Making use of a membrane electrode assembly (MEA) comprising dense ceramic electrolytes that can be either oxygen-anion or proton conducting as well as porous cermet electrodes, SOECs can produce wet or dry H 2 at temperatures between 500 1C and 1000 1C. [52][53][54] SOECs surpass todays commercialised electrolyser technologies such as AEL and PEM with respect to cell voltage, efficiency and specific power consumption (Table 1). However, the main advantage of SOECs lies in the thermal integration of downstream waste heat streams into the process, which is of particular interest and benefit in conjunction with process combination presented in this work.…”