Liquid metal batteries are proposed for low-cost grid scale energy storage. During their operation, solid intermetallic phases often form in the cathode and are known to limit the capacity of the cell. Fluid flow in the liquid electrodes can enhance mass transfer and reduce the formation of localized intermetallics, and fluid flow can be promoted by careful choice of the locations and topology of a battery's electrical connections. In this context we study four phenomena that drive flow: Rayleigh-Bénard convection, internally heated convection, electro-vortex flow, and swirl flow, in both experiment and simulation. In experiments, we use ultrasound Doppler velocimetry (UDV) to measure the flow in a eutectic PbBi electrode at 160 °C and subject to all four phenomena. In numerical simulations, we isolate the phenomena and simulate each separately using OpenFOAM. Comparing simulated velocities to experiments via a UDV beam model, we find that all four phenomena can enhance mass transfer in LMBs. We explain the flow direction, describe how the phenomena interact, and propose dimensionless numbers for estimating their mutual relevance. A brief discussion of electrical connections summarizes the engineering implications of our work.

液态金属电池被提议用于低成本的电网规模的能量存储。在其操作期间，固态金属间相通常在阴极中形成，并且已知会限制电池的容量。液体电极中的流体流动可增强质量传递并减少局部金属间化合物的形成，可通过谨慎选择电池电连接的位置和拓扑结构来促进流体流动。在这种情况下，我们在实验和仿真中研究了驱动流动的四种现象：瑞利-贝纳德对流，内部加热对流，电涡流和旋流。在实验中，我们使用超声多普勒测速仪（UDV）来测量160°C下共晶PbBi电极中的流量，并测试所有这四种现象。在数值模拟中 我们隔离现象并使用OpenFOAM分别模拟每个现象。通过UDV光束模型将模拟速度与实验进行比较，我们发现所有这四种现象都可以增强LMBs的传质。我们解释了流向，描述了现象如何相互作用，并提出了无量纲的数字来估计它们的相互关系。电气连接的简短讨论总结了我们工作的工程意义。