Research progress of alumina ultrafine powder modified lithium-ion battery separators

Abstract

Lithium-ion batteries with the advantages of high energy density and low self-discharge rate provide a strong guarantee for a long-lasting power supply. The separator, a critical component of lithium-ion batteries, plays a pivotal role in determining their performance and safety. As the demand for high energy density batteries grows, traditional polyolefin separators face significant challenges due to their inherent limitations, including high thermal shrinkage and poor electrolyte wettability. In this context, alumina ultrafine powder has emerged as an ideal material for separator functionalization, owing to its exceptional heat resistance, chemical stability, and surface modifiability. This paper presents the first in-depth review of the research progress in alumina ultrafine powder modification for lithium-ion battery separators, encompassing preparation methods, modification mechanisms, and performance impacts. It highlights the unique advantages of alumina in enhancing thermal stability, mechanical strength, and electrochemical properties of separators. This comprehensive analysis aims to provide clear directions for future research and accelerate advancements in this promising field.