Understanding Li Plating and Stripping Behavior in Zero-Excess Li Metal Batteries Using Operando Dilatometry

Abstract

Zero-excess Li metal batteries (ZELMB), in which the Li-metal anode is plated in situ on the anode current collector during initial charging, have received considerable attention in recent years. Such batteries hold enormous potential for increasing energy density and simplifying battery production, thus reducing costs, material, and energy requirements. However, transfer into application has so far been limited by challenges related to the non-uniform deposition behavior of lithium, which leads to inadequate performance and safety concerns. To meet these challenges, the electrochemical deposition behavior of lithium must be very well understood to derive and evaluate knowledge-based optimization approaches. For this purpose, advanced characterization methods are urgently needed. Herein the use of operando electrochemical dilatometry (OED) to study Li deposition and dissolution in ZELMB is demonstrated. We show how OED not only provides information on thickness changes during Li deposition and stripping, but also allows insights regarding morphology evolution and quantification of dead Li. The present work is intended to serve as an example to demonstrate the valuable insights that can be gained with OED and to encourage the scientific community to use it to support the development of advanced Li-, Na-, or K-metal batteries.

Less is more: a perspective on thinning lithium metal towards high-energy-density rechargeable lithium batteries

“…Such an ingenious conception simplifies the production process, reduces the costs for materials, and prominently enhances the energy density. 70,71 However, Li ions from the cathode would be consumed inevitably and quickly due to the formation of the solid electrolyte interphase (SEI) or dead Li. 72 On the other hand, if a Li-free material (e.g., S 8 , O 2 ) is appointed as the cathode, a thick LMA can be applied theoretically as the Li + ion source.…”

Unleashing the Potential of Sodium‐Ion Batteries: Current State and Future Directions for Sustainable Energy Storage

“…In such environments, Li–metal can react vigorously with many electrolytes, leading to the severe loss of active Li during cycling. Furthermore, in such extreme electrochemical windows and limited plating/stripping cycles, [ 175 ] uncontrolled nucleation of Li‐atoms on the surface can give rise to the formation of dendrites, which can result in short‐circuits and can even cause life‐threatening thermal runaways in batteries. [ 176 ] To make matters worse, conditions like dead Li can further arise due to the preferential dissolution of Li dendrites near the substrate during continuous discharge cycles.…”

Effect of cell pressure on the electrochemical performance of all‐solid‐state lithium batteries with zero‐excess Li metal anode

“…24 ASSBs with zero-excess Li metal anodes (also called anode-free Li metal batteries) have been proposed; various cell designs have been developed to overcome the limitations of lithium metal anodes; the limitations include the low Coulombic efficiency, dendrite growth, and high production cost. [25][26][27] Recently, Lee et al reported that an all-solid-state lithium metal battery with a sulfide-based solid electrolyte and an Ag-C composite anode exhibited a high energy density (> 900 Wh⋅L −1 ) and Coulombic efficiency (> 99.8%). 28 The Ag-C nanocomposite layer was crucial in ensuring a dense, uniform, and dendrite-free plating of Li metal.…”

“…ASSBs with zero‐excess Li metal anodes (also called anode‐free Li metal batteries) have been proposed; various cell designs have been developed to overcome the limitations of lithium metal anodes; the limitations include the low Coulombic efficiency, dendrite growth, and high production cost 25–27 . Recently, Lee et al.…”