According to recent news from the official website of the University of Cambridge in the UK, researchers at the school wrote in the latest issue of Nature that niobium tungsten oxide has a higher lithium pass rate and can be used to develop faster charging batteries. Moreover, the oxide Their physical structure and chemical behavior help them gain insight into how to build a safe, ultra-fast rechargeable battery.
When looking for new electrode materials, researchers often try to make the material particles smaller, but it is difficult to make a practical battery containing nanoparticles: the electrolyte will generate more unnecessary chemical reactions, so the battery life is not long, And the manufacturing cost is also high. The tantalum tungsten oxide used in the latest research has a hard and open structure that does not capture the intercalated lithium and is larger in size than many other electrode materials.
Kent Griffith, a postdoctoral fellow at the University of Cambridge's Department of Chemistry, explains: "Many battery materials are based on the same two or three crystal structures, but these tantalum tungsten oxides are fundamentally different. Oxides pass through oxygen' The pillars 'keep open, allowing lithium ions to pass through them in three dimensions, which means more lithium ions can pass through and at a faster rate. Measurements also show that lithium ions pass through the oxide faster than at typical electrodes The material is several orders of magnitude higher."
In addition to high lithium mobility, tantalum tungsten oxide is also easy to manufacture. Griffiths said: "Many nanoparticle structures require multiple steps to synthesize, but these oxides are easy to manufacture and do not require additional chemicals or solvents."
At present, most of the negative electrodes in lithium-ion batteries are made of graphite. Graphite has a high energy density, but when charged at a high rate, it tends to form a slender lithium metal fiber called "dendritic", which causes a short circuit. And the battery caught fire and even exploded.
Griffiths said: "In high-rate applications, safety is more important than any other operating environment. For fast-charging applications that require safer graphite alternatives, these and other similar materials are definitely worthy of attention. ”