Suppressing dendritic growth in electrochemical systems using magnetic fields

The growth of metal dendrites limits the efficiency of electrodeposition in electrochemical systems and constrains the lifetime of next-generation battery technologies. Strategies to tailor ionic transport have shown to be effective in delaying the onset of dendritic growth in electrolytic solutions. For example, imposing bulk flow is known to reduce boundary layer heights while enhancing the rate of ionic diffusion. Using a microfluidic reactor, we show how a magnetic field can also increase the deposition rate and energy efficiency of Cu electrodeposition using Lorentz forces. Magnetic fields are observed to induce vorticity, drive bulk flow, and enhance mixing near dendritic interfaces as they grow. These three-dimensional effects are distinct from imposed convection and offer a means to drive local transport around dynamic interfaces where current flows. Magnetic fields are shown to be a solution that enhances the extraction rate and energy efficiency of electrodeposition while limiting the height of metal dendrites.