????今后我們可能會使用空氣

????IBM研究院(IBM Research)科技部主任錢德拉塞卡爾?納拉延是電池500項目(Battery 500 Project)的成員。該項目的目標是，開發(fā)能夠提供行駛500英里路程所需電量的電池。IBM公司自身并不會生產(chǎn)電池，而是與消費類產(chǎn)品制造商開展合作，將這一技術帶到現(xiàn)實中。

????經(jīng)過多年的努力之后，納拉延看到了鋰-空氣技術的前景，即用汽車自身補給的氧氣取代石墨和其他的金屬。這類電池可以變得更輕，更安全，而且供電時間也更長。但是研發(fā)新的混合物，將它們制成新材料，并檢測其在數(shù)千輛汽車上的安全性，需要花費非常漫長的時間。

????納拉延說：“目前沒有一個指導性原則顯示，我們能夠年復一年地獲得進步，也沒有捷徑可以走。要得到這種范式，唯有創(chuàng)建一種全新的化學反應，而這一點并非創(chuàng)新所能企及的。”

????當前，鋰-空氣電池必須克服堵塞、內(nèi)部腐蝕和穩(wěn)定性問題。即便空氣電池能夠順利地演變?yōu)橐环N可行產(chǎn)品，納拉延認為，在今后，電池技術將不再是“通用型”?！袄?，對于電網(wǎng)存儲來說，它或許不是什么好技術。尤其是有尺寸要求的行業(yè)，我們或許很快將看到多種多樣的電池類型。”

????當前我們能做些什么：降低價格

????凱特林大學（Kettering University）的凱文?白和周軒（音譯）在實驗室中從事電池行業(yè)研究，但他們的談吐更像是買車人而不是實驗室的書呆子。周軒表示，現(xiàn)今的混合動力車存在多方面的優(yōu)缺點。

????周軒說：“目前，混合動力的售價是每千瓦時500-600美元，但合理的價格應該是200美元。而且冷卻系統(tǒng)的價格跟電池的價格是差不多的。如果汽車需要6,000美元的電池，那么就需要6,000美元的冷卻系統(tǒng)?！贝送猓瑒P文?白指出，這類電池的體積蠶食了本應屬于后備箱或乘坐的空間。兩位科學家也認為，電動汽車不應給人們帶來沉重的財務負擔。

????但是誰也不知道，哪些現(xiàn)有材料才能構造出最安全、發(fā)熱量最低和重量最輕的電池混合材料，而且其價格要比現(xiàn)有的產(chǎn)品便宜。

????現(xiàn)今在助聽領域使用的鋅-空氣電池重新激起了人們的興趣，而且尤為重要的一點在于，鋅很容易獲取。鈉-空氣電池也是一樣，成本更低，而且組裝起來更容易，只是潛在功率趕不上鋰-空氣電池。人們還嘗試過用硅來取代石墨和固體碳，但是硅并不便宜?；蛘撸覀兛梢灾粚Ｗ⒂诟纳茖嶒炇液湍ν熊囀褂玫匿?鐵電池的成本和性能。

????凱文?白表示，建造更大規(guī)模的電池廠、開發(fā)更好的電池管理工具以及更加智能的充電電網(wǎng)在很多方面要比等待一兩項新化合物獲得成功更為實在。

????凱文?白說：“我們實際上離使用全新電池的交通工具還很遠很遠。只有在新材料經(jīng)過10年的測試之后，汽車行業(yè)才能放心使用新材料?！彼硎?，人們至少要等到2020年才能看見使用鋅-空氣電池的四輪車輛，然后，人們需要更長的時間才能看到這一電池技術的成熟。

????What we might use next: air

????Chandrasekhar “Spike” Narayan, director of science and technology at IBM Research, is part of the Battery 500 Project. The goal is to get batteries to power a car of average cost on a 500-mile trip. IBM won’t build the batteries itself, but will partner with manufacturing and consumer companies to get them into the wild.

????After years of work, Narayan sees a future for lithium-air technology, which replaces graphite and other metals with oxygen, refreshed by the car itself. Such batteries could be lighter, safer, and last far longer. But working with new mixtures, pushing them into new materials, and seeing how safe they are over thousands of charge cycles takes a very, very long time.

????“There is no guiding principle that suggests you get improvement from year to year,” Narayan says. “There is no magic knob you can turn. The only way we can get to that kind of paradigm is a completely new kind of chemistry, and innovation doesn’t work like that.”

????Currently, lithium-air batteries have to overcome problems with blockages, internal rust, and stability. Even if air batteries are smoothed into a viable product, Narayan sees a future where battery technology is no longer one-size-fits all. “It may not be a great technology for power grid storage, for example. Especially when there is a size requirement, we may see differentiation among battery types soon.”

????What we can do in the meantime: get cheaper

????Kevin Bai and Xuan “Joe” Zhou at Kettering University work in labs and in battery industry research, but they talk like car shoppers than laboratory wonks. With the hybrid vehicles of today, Zhou notes, there are lots of trade-offs, in several ways.

????“Right now [hybrid] batteries are selling for $500 to $600 per kilowatt hour, but they should be $200,” Zhou says. “And every dollar you spend in the battery is another dollar in cooling. If the car needs a $6,000 battery, it’s a $6,000 cooling system.” What’s more, Bai notes, the size of such a battery eats up trunk or seating space. The scientists agree that an electric vehicle should feel like less of a financial albatross.

????But it’s anybody’s guess as to which current materials may work out to have the safest, coolest, and most lightweight mix, while still selling for less than today’s offerings.

????Zinc-air batteries, used in hearing aids today, are seeing renewed interest, especially given zinc’s easy availability. The same goes for sodium-air, which are cheaper and easier to assemble, if not as potentially powerful as lithium-air. There are also attempts to replace the graphite and carbon solids in batteries with silicon, though silicon isn’t cheap. Or we might just improve the cost and performance of the lithium-iron batteries in our drills and motorcycles in the meantime.

????In many ways, Bai says, building larger battery plants, better battery management tools, and a smarter power grid for charging is going to bear greater fruit than waiting on one or another chemical combo to pay off.

????“We are actually very far away from a brand-new battery for vehicles,” Bai says. “The automotive industry, they must feel they can stand behind 10 years of testing before they are comfortable trying a new material.” It will be at least 2020, he says, before you see zinc-air batteries in the first four-wheeled vehicles–and then a long while more before that battery technology matures.