Multi-objective optimisation analysis and load matching of a phosphoric acid fuel cell system

Performance evaluation and optimum design strategies of an acid water electrolyzer system for hydrogen production

“…to describe the relationship between m (viscosity), X (mole fraction of phosphoric acid), T, and k, which shows good agreement between the numerical results and the experimental values in the range of 298 T 473 K and 0.0147 X 1.0 [45,46]. By using Eqs.…”

“…where U act ¼ (RT/an e F)ln( j/j 0 ) is the activation overpotential losses related to the electrochemical kinetics [40,46], a is the transfer coefficient,j is the operating current density,j 0 is the exchange current density; U con ¼ mexp(nj ) is the concentration overpotential losses caused by mass transfer [40,46], m and n are two constants which are independent of the current density; U ohm ¼ jt ele /k is the ohmic overpotential losses mainly caused by the resistance of electrolyte as the resistance of electrodes is negligible compared with that of electrolyte [43,46],t ele is the thickness of the H 3 PO 4 electrolyte, and k is the specific conductivity of the H 3 PO 4 solution. Based on the experiment data, Chin et al [44] introduced the following equation…”

“…When the PAWE is operated at high current densities, there exists an optimal value for circulating electrolyte concentration X opt at which the input voltage attains its minimum U min , as shown in Fig. 2, where the concrete values of X opt for some given operating temperatures can be obtained through numerical calculation [46]. By using Eqs.…”

Maximum power output and load matching of a phosphoric acid fuel cell-thermoelectric generator hybrid system

“…The overall reaction is H 2 þ 0.5O 2 / H 2 O þ electricity þ heat. The basic thermodynamic relationship for the overall reaction can be expressed as ÀDH ¼ ÀDG À TDS [5], where DG is the Gibbs free energy change of the reaction, i.e., electrical energy, which is consumed by both the internal dissipation and the external load, and DS is the entropy production of the reaction. ÀTDS stands for the thermal energy released by the reaction, which may result in a temperature rise inside the fuel cell.…”

Estudio comparativo de las diferentes tecnologías de celdas de combustible

“…Como se puede observar, un aspecto importante en este tipo de celdas es la óptima concentración del electrolito para diferentes temperaturas, así como el rendimiento, eficiencia y sobrepotencial (activación, concentración, óhmico, etc.) 35 . …”