How Electrolyte Conductivity Governs Lithium-Ion Battery Performance

A study conducted by Yuichi Itou et al. was published in the Journal of Power Sources.

Lithium-ion batteries are essential for modern society, powering electric vehicles and portable electronics. To meet growing demands for higher power and durability, it is crucial to understand not only electrode materials but also the role of electrolytes, which transport lithium ions inside the battery. However, the quantitative impact of electrolyte conductivity on battery performance has remained unclear. Previous studies mainly focused on electrode structures, while the contribution of electrolyte properties to internal resistance was not fully clarified.

In this study, four different lithium salts were systematically compared using cylindrical batteries and electrochemical impedance analysis with symmetric cells. The resistance components inside porous electrodes were separated and quantified. The results clearly show that higher electrolyte conductivity leads to lower ionic resistance within electrodes and improved power capability. Among the tested electrolytes, LiFSI exhibited the highest conductivity and the lowest resistance, resulting in superior battery performance. These findings highlight the importance of electrolyte design in addition to electrode optimization. The insights provided by this work offer a rational guideline for developing high-performance lithium-ion batteries, contributing to future electric mobility and energy storage technologies.

Title: Influence of Electrolyte Conductivity on the Performance of Lithium-ion Batteries: An Electrochemical Impedance Analysis Using Symmetric Cells
Authors: Itou, Y., Ogihara, N., Kawauchi, S.​
Journal Name: Journal of Power Sources​
Published: November 30, 2025
https://doi.org/10.1016/j.jpowsour.2025.238103