Eliminating Tip Dendrite Growth by Lorentz Force for Stable Lithium Metal Anodes

Lithium metal anodes are deemed as the Holy Grail for next generation high energy density batteries, due to the reported highest specific capacity (3860 mAh g(-1)) and the lowest negative electrochemical potential (-3.04 V vs the standard hydrogen electrode). However, the notorious tip-induced dendrite growth leads to low Coulombic efficiency, restricted lifespan, and even catastrophic short-circuits, blocking the roadmap of their commercialization. Here, a magnetic field is introduced into the lithium plating process. The Li+ concentrated around the tips by the uneven electric field distribution can be taken off the hotpots by the Lorentz force and the tip dendrite growth can be eliminated. The relationship between current density and magnetic flux intensity is established by monitoring the deposited lithium morphology as well as the electrochemical performance, which is confirmed by mathematic modeling and COMSOL Multiphysics simulation. It is also demonstrated that the Lorentz force-induced tip dendrite elimination can be utilized practically by assembling permanent magnet-containing prototype coin cell. It is anticipated that this physical approach can be applied to other high energy density systems as well.