Affiliation:
1. Department of Mechanical and Aerospace Engineering University of Virginia 122 Engineer's Way Charlottesville VA 22904‐4746 USA
Abstract
AbstractLithium dendrite‐induced short circuits and material loss are two major obstacles to the commercialization of lithium–sulfur (Li−S) batteries. Here, a nanocarbon composite consisting of cotton‐derived Fe3C‐encapsulated multiwalled carbon nanotubes (Fe3C‐MWCNTs) and graphene effectively traps polysulfides to suppress lithium dendrite growth is reported. Machine learning combined with molecular dynamics (MD) simulations unveils a new polysulfide‐induced lithium dendrite formation mechanism: the migration of polysulfides away from the anode drags out lithium protrusions through localized lattice distortion of the lithium anode and traps lithium ions in the surrounding electrolyte, leading to lithium dendrite formation. The Li−S battery, constructed using the composite of cotton‐derived Fe3C‐MWCNTs and graphene that serves as both the sulfur host and the anode interlayer, exhibits exceptional cycling stability, impressive capacity retention, and effective mitigation of lithium dendrite formation. The findings offer valuable strategies to prevent lithium dendrite formation and enhance understanding of lithium dendrite growth in Li−S batteries.
Funder
National Science Foundation
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry