Simulation of thermal properties of the liquid metal batteries

With the development of intermittent renewable energy technologies (such as wind and solar) large-scale access into the electric grid, a low cost high efficiency energy storage medium is indeed to greatly improve the ability of the power grid adopting the renewable energy., among all kinds of energy storage technologies, batteries have long been considered a very promising choice owing to their seldom pollution, high efficiency, low maintenance, and flexibility in power and energy characteristics, besides its long service life. Here we describe the liquid metal battery which is a newly developed and can be self-heated. This cheap and efficient energy storage medium will meets the specifications for power grid applications. This paper focuses to analysis the self-heated mechanism in this new battery, which is the vital factor to ensure the startup and reliability of the battery. The analysis is based on the finite element numerical methods with a three-dimensional thermal simulation model of liquid metal battery, and compares the temperature distribution under various current densities, different battery electrolyte sizes respectively. Simulation results show that both the current densities and the thickness of the electrolyte have a critical value above which the liquid metal battery can achieve a self-heating state. We also verify the simulation results theoretically from the view of mathematical formula, and reveal the ways to get self-heated for this battery.