Guidance KPF 6 - and KFSI-based electrolytes in EC/DEC solvents selection for potassium-based batteries
Year: 2025
Type: article
Abstract: Electrolytes play a key role in determining the electrochemical performance, safety, and lifespan of potassium-based batteries, making their selection and optimization a critical area of research. This study systematically investigates the effects of two major potassium-based battery electrolytes, KPF6 and KFSI in EC/DEC solvents, on battery performance, solid electrolyte interphase (SEI) stability, aluminum (Al) current collector corrosion behavior, electrochemical stability window, and dendrite growth issue. Experimental results reveal that KFSI electrolyte significantly outperforms KPF6 in terms of cycling stability, rate capability, and Coulombic efficiency (CE), primarily due to the formation of a high-quality SEI on electrode surface. Through XPS and TOF-SIMS analyses, we construct the SEI structure for both electrolytes, and find that the SEI formed by KFSI is more uniform and stable. Additionally, KPF6 exhibits weaker corrosivity towards the Al current collector compared to KFSI due to the formation of an AlF3 layer with higher oxidation stability on Al surface. Furthermore, in-situ optical microscopy observations indicate that dendrite growth in KFSI electrolyte is more uniform, preventing the aggregates. These findings provide essential experimental evidence and theoretical support for optimizing electrolyte in potassium-based batteries.
Source: Nano Research
Authors: Jiamei Liu, Xiaowei Shi, Bonan Tan, Huandi Zhang, Junpeng Liu, Haixiao Kang, Zhan Gao, Lei Li
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $5,290
OpenAlex ID: W4415605312