skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Beyond Local Solvation Structure: Nanometric Aggregates in Battery Electrolytes and their Effect on Electrolyte Properties

Journal Article · · ACS Energy Letters

Electrolytes are an essential component of all electrochemical storage and conversion devices, such as batteries. In the history of battery development, the complex nature of electrolytes has often been a bottleneck. Fundamental knowledge of electrolyte systems encompasses elucidation of structure-property relationships of the solution species. Recently, nanometric aggregates have been observed in several classes of electrolytes, including super-concentrated, redox-flow, multivalent, polymer, and ionic liquid-based electrolytes. Compared with the well-studied local solvation structures such as contact ion pairs and solvent-separated ions, these aggregates impose unique effects on the ion distribution and transport both within bulk electrolytes and at electrode/electrolyte interfaces. This Perspective highlights the discovery of the aggregates in various battery electrolytes and their impact on electrolyte properties. We also present an outlook for future studies of this emerging field of nanometric aggregates and the need for the development of new experimental and computational tools to study their properties.

Research Organization:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Organization:
USDOE Office of Science - Office of Basic Energy Sciences - Joint Center for Energy Storage Research (JCESR)
DOE Contract Number:
Journal Information:
ACS Energy Letters, Vol. 7, Issue 1
Country of Publication:
United States

References (59)

Energy storage emerging: A perspective from the Joint Center for Energy Storage Research journal June 2020
The Mystery of Electrolyte Concentration: From Superhigh to Ultralow journal November 2020
Ionic Conduction and Solution Structure in LiPF 6 and LiBF 4 Propylene Carbonate Electrolytes journal July 2018
The Coupling between Stability and Ion Pair Formation in Magnesium Electrolytes from First-Principles Quantum Mechanics and Classical Molecular Dynamics journal February 2015
Glyme−Lithium Salt Phase Behavior journal July 2006
Asymmetric Composition of Ionic Aggregates and the Origin of High Correlated Transference Number in Water-in-Salt Electrolytes journal January 2020
Ion Pairing and Diffusion in Magnesium Electrolytes Based on Magnesium Borohydride journal December 2017
Self-Assembled Solute Networks in Crowded Electrolyte Solutions and Nanoconfinement of Charged Redoxmer Molecules journal October 2020
Ionic Aggregate Structure in Ionomer Melts: Effect of Molecular Architecture on Aggregates and the Ionomer Peak journal December 2011
Liquid Structure with Nano-Heterogeneity Promotes Cationic Transport in Concentrated Electrolytes journal October 2017
Nanometric Water Channels in Water-in-Salt Lithium Ion Battery Electrolyte journal October 2018
Signatures of Ion Pairing and Aggregation in the Vibrational Spectroscopy of Super-Concentrated Aqueous Lithium Bistriflimide Solutions journal January 2020
Structure and Dynamics of Polysulfide Clusters in a Nonaqueous Solvent Mixture of 1,3-Dioxolane and 1,2-Dimethoxyethane journal February 2019
Theory of ion aggregation and gelation in super-concentrated electrolytes journal June 2020
Ion Clusters and Networks in Water-in-Salt Electrolytes journal May 2021
Dependence of the dielectric constant of electrolyte solutions on ionic concentration: A microfield approach journal July 2016
Modeling and Simulation of Concentrated Aqueous Solutions of LiTFSI for Battery Applications journal May 2020
Water-in-Salt LiTFSI Aqueous Electrolytes. 1. Liquid Structure from Combined Molecular Dynamics Simulation and Experimental Studies journal April 2021
Competitive Pi-Stacking and H-Bond Piling Increase Solubility of Heterocyclic Redoxmers journal November 2020
Effect of Polymer Architecture and Ionic Aggregation on the Scattering Peak in Model Ionomers journal March 2011
Effect of Salt Concentration on Ion Clustering and Transport in Polymer Solid Electrolytes: A Molecular Dynamics Study of PEO–LiTFSI journal August 2018
Difference between approximate and rigorously measured transference numbers in fluorinated electrolytes journal January 2019
Theoretical Analysis of Carrier Ion Diffusion in Superconcentrated Electrolyte Solutions for Sodium-Ion Batteries journal February 2018
Mechanisms of Magnesium Ion Transport in Pyrrolidinium Bis(trifluoromethanesulfonyl)imide-Based Ionic Liquid Electrolytes journal November 2014
Direct Evidence for Li Ion Hopping Conduction in Highly Concentrated Sulfolane-Based Liquid Electrolytes journal November 2018
Transport in Superconcentrated LiPF 6 and LiBF 4 /Propylene Carbonate Electrolytes journal October 2019
Ion Correlations and Their Impact on Transport in Polymer-Based Electrolytes journal February 2021
Observation of separate cation and anion electrophoretic mobilities in pure ionic liquids journal February 2014
Direct determination of ionic transference numbers in ionic liquids by electrophoretic NMR journal January 2015
Lithium Transference Numbers in PEO/LiTFSA Electrolytes Determined by Electrophoretic NMR journal January 2019
Negative Transference Numbers in Poly(ethylene oxide)-Based Electrolytes journal January 2017
High Transference Number of Na Ion in Liquid-State Sulfolane Solvates of Sodium Bis(fluorosulfonyl)amide journal January 2020
Uncharted Waters: Super-Concentrated Electrolytes journal January 2020
Molecular Dynamics Simulations of Multicomponent Diffusion. 1. Equilibrium Method journal November 2004
Li + Transference Numbers in Liquid Electrolytes Obtained by Very-Low-Frequency Impedance Spectroscopy at Variable Electrode Distances journal January 2016
How efficient is Li + ion transport in solvate ionic liquids under anion-blocking conditions in a battery? journal January 2018
Transport phenomena in electrolyte solutions: Nonequilibrium thermodynamics and statistical mechanics journal November 2020
Transport anomalies emerging from strong correlation in ionic liquid electrolytes journal July 2019
Insights into the Structure and Transport of the Lithium, Sodium, Magnesium, and Zinc Bis(trifluoromethansulfonyl)imide Salts in Ionic Liquids journal August 2018
Systematic Computational and Experimental Investigation of Lithium-Ion Transport Mechanisms in Polyester-Based Polymer Electrolytes journal July 2015
Unusual Stability of Acetonitrile-Based Superconcentrated Electrolytes for Fast-Charging Lithium-Ion Batteries journal March 2014
High-Voltage Lithium-Metal Batteries Enabled by Localized High-Concentration Electrolytes journal March 2018
The use of ethyl acetate as a sole solvent in highly concentrated electrolyte for Li-ion batteries journal February 2015
Efficient Lithium Metal Cycling over a Wide Range of Pressures from an Anion-Derived Solid-Electrolyte Interphase Framework journal February 2021
General Observation of Lithium Intercalation into Graphite in Ethylene-Carbonate-Free Superconcentrated Electrolytes journal March 2014
Impact of ionic aggregate structure on ionomer mechanical properties from coarse-grained molecular dynamics simulations journal October 2017
Potential-Dependent Layering in the Electrochemical Double Layer of Water-in-Salt Electrolytes journal July 2020
Enhancing the performance of lithium oxygen batteries through combining redox mediating salts with a lithium protecting salt journal April 2021
Nanoheterogeneity of LiTFSI Solutions Transitions Close to a Surface and with Concentration journal February 2021
Interfacial Speciation Determines Interfacial Chemistry: X‐ray‐Induced Lithium Fluoride Formation from Water‐in‐salt Electrolytes on Solid Surfaces journal October 2020
Localized High Concentration Electrolyte and Its Effects on Polysulfide Structure in Solution journal September 2021
Directing the Lithium–Sulfur Reaction Pathway via Sparingly Solvating Electrolytes for High Energy Density Batteries journal May 2017
Deep Potential Molecular Dynamics: A Scalable Model with the Accuracy of Quantum Mechanics journal April 2018
A fast neural network approach for direct covariant forces prediction in complex multi-element extended systems journal September 2019
Machine learning of accurate energy-conserving molecular force fields journal May 2017
Generalized Neural-Network Representation of High-Dimensional Potential-Energy Surfaces journal April 2007
Enhanced sampling in molecular dynamics journal August 2019
Size and composition distribution dynamics of alloy nanoparticle electrocatalysts probed by anomalous small angle X-ray scattering (ASAXS) journal January 2009
Concentration and velocity profiles in a polymeric lithium-ion battery electrolyte journal January 2020