Batteries,as you may have figured out by now,have a few problem,actually.They don't hold nearly enough power.They're very expensive.And above all,they're explosive.That's a real problem for Samsung
Isn't anyone going to try to invent a better battery?Fortunately,a Tufts University professor named Mike Zimmerman,is breathtaking close to cracking the powerful-cheap-safe battery problem.
Inside every lithium-ion battery on earth,there's a positive electrode (阳极) and a negatively charged one.They're separated by a thin sheet.The rest is filled up with a liquid called the electrolyte（电解质）.
When you charge the battery,positively charged ions（离子）flow through that liquid from the negative side to the positive side.Then,as you use the battery to power your gadget,they flow back again.
The key here is that electrolyte juice.It's easily lighted.What Zimmerman has done is pretty amazing: He's created a battery that gets rid of the liquid.In its place: A special plastic film,solid and not flammable（易燃的）.Yet it allows the free flow of the ions,just as the electrolyte does.Zimmerman's plastic doesn't catch fire even if you try to light it with a lighter.
We call them lithium ion batteries because they do not,in fact,use actual lithium metal.That's too bad,because lithium metal batteries can store at least twice as much power! The only reason why we don't use lithium-metal batteries is that they're even more dangerous than lithium ion.
But if there's no flammable liquid,there's no risk of fire.So Zimmerman's batteries do use actual lithium metal,and therefore hold twice as much charge.Imagine: Three days of life on every phone charge instead of one and a half.Four hundred miles in an electric car instead of 200.And so on.It's a big,big deal.
41.Why do Zimmerman’s invention use actual lithium metal?
A.Lithium metal are not easy to light. B.Zimmerman’s batteries include no liquid.
C.Lithum-metal batteries are safer than lithium-ion. D.Ordinary batteries use the safe lithium metal.
42.What can we know about Zimmerman’s batteries?
A.They are safe and hold large power. B.They are risky but store much power.
C.They are unsafe but hold much charge. D.They are unsafe but convenient.
43.What can we know from the underlined sentence in Paragraph 7?
A.We can make a big deal with Zimmerman. B.Zimmerman’s batteries sound nice but unrealistic.
C.Zimmerman wants to make a deal with producers. D.Zimmerman’s batteries will make a difference to our life.
44.How is the passage mainly developed?
A.By giving descriptions. B.By listing examples.
C.By making comparisons. D.By following time order.
45.What does the passage mainly present?
A.An introduction to Tufts professor. B.Information on using the old type of batteries.
C.The author’s interview with Tufts professor. D.Tufts professor’s invention of a non-exploding battery.
答案 41-45 BADCD