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The rechargeable lithium-ion (锂离子) battery market is worth more than ＄50 billion. Lithium-ion batteries, whose demand continues to go up day by day, are used in a wide range of electronic devices. They are made of four main components, and cathode (阴极) is one of them. The cathode’s active material type is what determines the capacity of a battery.

A recent study, led by Wang Yan, a material scientist of Worcester Polytechnic Institute, finds that lithium-ion batteries made with recycled cathodes work better than those with new cathodes.

“The battery industry is expected to grow sharply in the next decade. This high demand has led companies to go to extremes, like increasing deep-sea mining, to gain access to the minerals used in lithium-ion batteries,” Wang said. “Mining minerals will have environmental impacts. Recycling spent lithium-ion batteries offers a way out.”

But until now, the prospect of using recycled materials in lithium-ion batteries has some manufacturers (制造商) worrying that it could impact performance. Thus, lithium-ion batteries are still not widely recycled. Aware of decreasing resources and environmental impact, Wang and other researchers set out to find a way to make recycling lithium-ion batteries economically practical. Through experiments, they could recover more than 90% of the key metals from spent batteries. These recovered metals became the basis of the new recycled battery’s cathode’s active material.

In tests between Wang’s team’s recycled batteries and brand-new batteries of the same composition, the recycled batteries outperform the new ones in their ability to maintain capacity. It took 11,600 charge cycles for recycled cathode batteries to lose 30 percent of their original capacity. That was about 50 percent better than the 7,600 observed cycles for new cathode batteries, the team reported. Those thousands of extra cycles could translate into years of better battery performance, even after repeated use and recharging.