Electrochemical Modelling of a Sodium Metal based Desalination Battery for Electrolysis and Trigeneration using Direct-Current Generator in Ships

Abstract

The objective of this study is to present a generalized nonlinear electrochemical model formulation for a desalination rechargeable battery of seawater using Na metal redox flow cell. The complete scheme in the proposed study comprises of i) a desalination battery redox flow cell; ii) electrolysis of water for hydrogen production in a separate electrochemical cell; and iii) trigeneration for heat, cooling {(heating, ventilating, and air-conditioning) HVAC} and electric power using direct-current generator’s engine utilizing hydrogen blend as fuel. Once this energy technology is developed, it will be utilized in the ship’s power plant for improving its energy efficiency. This paper is focusing on the observer-based method to estimate, in real-time, the state of charge (SoC) of a generalized redox flow desalination battery using Linear Matrix Inequalities (LMI) technique. A nonlinear observer is proposed, which will be designed and validated through simulation with an experimental prototype exclusively designed for ships.

Key Innovations

• Electrochemical Modelling of a Sodium Metal based Desalination Battery using Oberver Design.
• To predict the behaviour of redox flow desalination batteries across various applications, control strategies, and arrangement scenarios in ships, marine electric vehicles and renewable energy integration at seaports.

Practical Implications

The LMI technique is proposed which will be used to simultaneously compute controller and observer gains in the presence of noise for a nonlinear parameter varying (NLPV) system subject to disturbances with LMI constraints for a robust model predictive control (MPC) optimization problem (Lan et. al., 2021).