Impact of Salt Concentration on Nonuniform Lithium Electrodeposition through Rigid Block Copolymer Electrolytes
There is a growing demand for higher energy density lithium batteries. One approach for addressing this demand is enabling lithium metal anodes. However, nucleation and growth of electronically conductive protrusions, which cause short circuits, prevent the use of this technology with liquid electrolytes. The use of rigid solid electrolytes such as polystyrene-b-poly(ethylene oxide) electrolytes is one solution. An additional requirement for practical cells is needed to use electrolytes with high salt concentration to maximize the flux of lithium ions in the cell. The first systematic study of the effect of salt concentration on the morphology of electrodeposited lithium through a rigid block copolymer electrolyte is presented. The nature, areal density, and morphologies of defective lithium deposits created during galvanostatic cycling of lithium-lithium symmetric cells were determined using hard X-ray microtomography. Cycle life decreases rapidly with increasing salt concentration. X-ray microtomography reveals the presence of multiglobular protrusions, which are nucleated at impurity particles at low salt concentrations; here, the areal density of defective lithium deposits was independent of salt concentration. Finally, at the highest salt concentration, this density increases abruptly by a factor of about 10, and defects were also nucleated at locations where no impurities were visible.
- Research Organization:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- AC02-05CH11231
- OSTI ID:
- 1619145
- Journal Information:
- ACS Applied Materials and Interfaces, Vol. 11, Issue 51; ISSN 1944-8244
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Evolution of Protrusions on Lithium Metal Anodes Stabilized by a Solid Block Copolymer Electrolyte Studied Using Time-Resolved X-ray Tomography
Growth of Lithium Dendrites and Globules through a Solid Block Copolymer Electrolyte as a Function of Current Density