题型:阅读理解 题类:常考题 难易度:普通
陕西省汉中市(略阳天津高级中学、镇坝中学、留坝中学、西乡二中等9所学校)2020届高三上学期英语第一次校际联考试卷
When a laptop or smartphone battery starts losing its power, the only options are to buy an expensive replacement, or just keep it plugged in all the time. But a woman Mya Le Thai may have found the answer to this problem.
Thai was frustrated that the batteries for her wireless devices degraded(降级)over time, until they failed to charge fully. She did not like having to keep her laptop connected to an electrical outlet to keep it powered on. So, she decided to do something about that problem. At first, she and her team at UC Irvine thought about inventing a new battery. But as they experimented, Thai discovered something that might permit lithium—ion(锂离子)batteries to last forever.
Lithium-ion batteries power most wireless devices. Over time, the batteries lose the ability to hold a charge. Most of these batteries have a life span of about 7,000 charging cycles before they die. One of the reasons lithium—ion batteries degrade is their use of nanowires to carry electricity. Nanowires are extremely thin. A human hair is thousands of times thicker, for example. Nanowires are extremely efficient carriers of electricity, which makes them useful in batteries.
But, Thai had a theory—the nanowires might last longer if covered with a gel(凝胶). She and her team tested this theory. "It was a long process and a lot of work, "Thai said. The team tried many coverings for the wires. PMMA, a type of plastic, was one of them. The nanowires were coated with PMMA and cycled through charges 200, 000 times. The PMMA-coated nanowires showed no evidence of damage. The results suggest that batteries could last forever, without losing charging ability.
Thai hopes to continue her research to understand why this gel works so well and to see if any other gel could create better results and she is enjoying the publicity about her discovery. She said she never expected her research to get media coverage. "It's kind of cool," she said. "I'm really glad people are showing interest in my work and not just in the work itself, but also in technology and energy."
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