A joint research team from Tianmushan Lab and Tsinghua University has announced a major research finding in the regulation of electrolytes for lithium metal batteries. The team has successfully developed high-stability lithium metal pouch cells with energy densities reaching the 600 Wh/kg level, according to research recently published in the prestigious international journal Nature Communications.

The finding comes at a critical time for the rapidly expanding “low-altitude economy.” While market demand for drones and electric vertical take-off and landing (eVTOL) aircraft continues to surge, widespread commercial adoption has been hindered by limited flight endurance. Current commercial lithium batteries, which utilise graphite anodes, are approaching their theoretical energy density limit of approximately 350 Wh/kg, making it difficult to meet the requirements for long-duration operations.

Lithium metal batteries are widely regarded as the primary solution to this endurance bottleneck due to the high capacity of their anode materials. However, the industry has struggled to balance high energy density, long cycle life, and safety, as these batteries are prone to electrolyte decomposition and the growth of lithium dendrites under high-voltage operating conditions.

To address these challenges, the research team implemented a novel design strategy utilising an additive-strong coordination solvation structure to develop a new type of electrolyte additive. This innovation creates a thin, dense protective film on the cathode surface, mitigating material damage caused by high-voltage cycling. Simultaneously, it constructs a stable interface layer on the lithium metal anode, which suppresses the formation of lithium dendrites, significantly improves lithium-ion transport efficiency, and reduces safety risks.

According to test data, 10Ah pouch cells using high-nickel ternary cathodes achieved an energy density of 550.7 Wh/kg, retaining 80% of their capacity after 180 cycles. When paired with lithium-rich manganese-based cathode materials, the reversible specific energy further increased to 602.5Wh/kg – an improvement of over 50% compared to current mainstream power batteries.

Despite these impressive results, the researchers noted that the technology is currently in the laboratory research stage. Further technical iterations will be required before the battery can be scaled for mass commercial application.

Source: CarNewsChina (View original)