High-Performance Lithium-metal Batteries

Lithium-ion batteries based on graphite anodes have almost reached the upper limit of their theoretical specific capacity but still cannot meet the high energy density required for the long range of electric vehicles. Lithium metal is considered to be the most promising next-generation high energy density lithium battery anode material due to its ultra-high theoretical specific capacity (3,860 mAh g-1) and extremely low standard electrochemical negative potential (-3.040 V vs. Standard hydrogen electrode). However, the high reactivity of lithium metal and uncontrolled lithium dendrite growth during repeated platting/striping lead to low coulombic efficiency and serious safety issues.

In recent years, numerous research effort is contributed to lithium metal batteries, which has brought a new and deep understanding of Li metal protection. Considering the challenges of a lithium anode, i.e. the uncontrollable growth of Li dendrite results in serious safety concerns, while the irreversible and constant reaction between Li and electrolyte causes an unstable and thick SEI layer on the electrode surface, which will increase the internal resistance and shorten the cycle life. Additionally, the infinite volume expansion and pulverization during repeat cycling result in fast capacity decay and low coulombic efficiency. Various strategies are developed to improve the electrochemical performance of lithium metal batteries.

For dense lithium foils, uniform deposition could be achieved by forming lithium alloys or by confining them in a specially structured matrix. The interfacial modification includes ex-situ Li foil treatment, separator, and copper decoration. Artificial SEIs coatings on lithium metal surfaces could reduce side effects. Liquid electrolyte modification will become a competitive choice for future battery electrolytes. Alternatively, solid-state electrolytes with a high shear modulus coated on lithium foils could prevent dendrite penetration. Solid electrolytes are preferred over liquid electrolytes because of their advantage of suppressing dendrite formation.

For further exploring the effective strategy to improve the performance of lithium metal batteries, we are launching this research topic on “High-performance lithium metal batteries. Research on all kinds of methods to achieve stable and high-performance lithium metal battery are invited.

Here we will focus on the research of lithium metal batteries, including different strategies, research areas may include, but are not limited to the following:
• Lithium metal protection
• Lithium metal alloy
• Nanostructured design of lithium metal anode
• Artificial SEI layer, liquid electrolyte modification
• Solid-state electrolyte and interface with Li metal
• All types of primary and rechargeable lithium batteries

Original research articles, review articles, letters, or communication are fine.