Gradient Host for Bottom-Up Deposition of Lithium Metal Anode

Lithium metal batteries have been attracting an abundance of attention recently as a powerful competitor of the next-generation advanced energy storage technologies. However, lithium dendrite formation can result in decreased battery lifespan and even safety issues, inhibiting the widespread application of lithium metal batteries. The conductive hosts of lithium metal anode are proven to be an effective method to prevent lithium dendrite formation and achieve outstanding electrochemical performance of lithium metal batteries. However, the surface deposition of Li ions decreases the utilization of the conductive host. Therefore, this Review introduces the design principle and recent advances to render the bottom-up deposition of a lithium metal anode. On one hand, conductivity and lithiophilicity gradient hosts are summarized to realize the "bottom-up" lithium deposition and efficiently limit the growth of lithium dendrites. On the other hand, the future prospects and challenges of host design associated with the "bottom-up" lithium deposition technique are discussed. This Review intends to provide novel insights for the development of gradient materials design and lithium metal batteries with long lifespan and high safety.