Fabrication of Ultra-thin Lithium Foil and Application in Pre-lithiation

Novel ultra-thin lithium foils, present significant advantages over conventional lithium foils in terms of energy density, safety, and material cost reduction for lithium metal batteries. These benefits stem from the enhanced electrochemical performance and efficiency that ultra-thin foils can deliver. However, the industrial production of such foils is fraught with challenges. Key issues include the potential for creases and damage during the manufacturing process, as well as the complexity of the techniques required to produce them at scale. Thus, there is an urgent need to innovate existing manufacturing methods to meet the growing industrial demand for ultra-thin lithium foils. In addition to their manufacturing challenges, ultra-thin lithium foils play a crucial role in enhancing the initial coulomb efficiency (ICE) and extending the cycle life of lithium-ion batteries. They are commonly employed to replenish active lithium on the cathode side, compensating for the lithium consumed during the initial charging and discharging phases. However, excessive lithium metal can lead to side reactions with the electrolyte, negatively affecting battery life and safety. Therefore, careful management of lithium deposition is essential to optimize battery performance while ensuring safety. This review specifically addresses the challenges associated with conventional lithium foil manufacturing, providing a detailed analysis of the underlying issues and proposing targeted strategies to overcome them. Relevant examples from recent research will be presented to illustrate successful approaches. Furthermore, the review explores novel preparation methods for ultra-thin lithium foils, evaluating their feasibility for industrial applications. Additionally, the review will summarize the current use of lithium foils in pre-lithiation processes, emphasizing the trend toward integrating ultra-thin lithium foil manufacturing with these processes. This integration is expected to enhance the performance of lithium batteries while simultaneously addressing manufacturing challenges. Ultimately, this review aims to provide valuable insights and inspiration for researchers in the field, serving as a comprehensive resource to stimulate further innovation in lithium foil manufacturing and application.