Chinese battery revolution? New electrolyte extends lifespan

Scientists at Nankai University in China have announced a major technological advance in lithium-metal batteries. They have developed a new type of electrolyte that, in laboratory tests, enabled cells to operate stably for more than 9,000 hours and, in some designs, retain more than 80% of their original capacity after 2,500 charging cycles. This development could fundamentally transform battery systems for electric vehicles and grid-scale energy storage.

The key is a new electrolyte – a substance that transfers ions between a battery's anode and cathode. The team used a so-called “eutectic gel electrolyte”, referred to as a deep eutectic gel electrolyte (DEGE). It is based on a mixture of fluorinated amides, which increase ion conductivity while stabilising the electrode surface.

In conventional lithium-metal cells, thin metallic protrusions known as dendrites form during charging. These can shorten a cell's lifespan or cause overheating. The new electrolyte prevents this phenomenon by creating a more even distribution of ions across the electrode surface. The result is a longer lifespan and greater safety.

According to laboratory tests, cells using this electrolyte operated continuously for more than 9,000 hours, equivalent to roughly one year of operation. They maintained stable performance even after thousands of charging cycles. The gel structure also improved thermal resistance – the cells withstood testing at 80 °C without a significant drop in performance.

Longer battery lifespans mean lower costs, less waste and higher returns on investment. If this technology were deployed in practice, the lifespan of battery systems in electric vehicles or storage facilities could increase by tens of percent.

The higher energy density of this type of technology could realistically add tens of percent to electric vehicle range or enable significantly lighter batteries with the same capacity.

In grid-scale storage, batteries capable of thousands of stable cycles would improve returns on investment and ease pressure on the extraction of critical raw materials. Batteries that can withstand thousands of cycles without significant capacity loss would enable substantially more efficient use of electricity from renewable sources.

Improved safety and thermal stability are also crucial for deployment in large-scale energy storage systems. The new electrolyte reduces the risk of fires and enables operation even in more demanding climatic conditions.

If the research can be transferred from the laboratory to industrial production, it could represent one of the biggest leaps in battery technology of the past decade. The first commercial applications are most likely to be in segments where price is secondary to performance: the military, aviation and the premium electric vehicle segment.