POSTECH Develops Durable LLO Materials for Next-Gen Lithium-Ion Batteries

A research team at the Pohang University of Science and Technology (POSTECH) in South Korea has developed a groundbreaking strategy to enhance the durability of lithium-rich layered oxide (LLO) materials. These materials are considered crucial for the next generation of positive electrodes in lithium-ion batteries (LIBs), promising a significant extension of battery life. The research findings have been published in the journal "Energy & Environmental Science."

Lithium-ion batteries are indispensable in fields such as electric vehicles and energy storage systems (ESS). LLO, by reducing the use of nickel and cobalt while increasing the proportions of lithium and manganese, boasts an energy density 20% higher than traditional nickel-based cathodes. As a more economical and sustainable option, LLO has garnered widespread attention. However, issues of capacity and voltage decay during charge-discharge cycles have hindered its commercialization.

The POSTECH team's research revealed that oxygen released during cycling is a critical factor leading to structural instability in LLO. They hypothesized that enhancing the chemical stability at the cathode-electrolyte interface could effectively suppress oxygen release. Building upon this hypothesis, the researchers significantly reduced oxygen emissions and enhanced the stability of the cathode-electrolyte interface by improving the electrolyte composition.

This improvement has led to outstanding performance. After 700 charge-discharge cycles, the new electrolyte achieved an energy retention rate of 84.3%, while the traditional electrolyte only reached 37.1% after 300 cycles.