{"id":6147,"date":"2012-06-27T10:30:05","date_gmt":"2012-06-27T17:30:05","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=6147"},"modified":"2012-06-27T10:30:06","modified_gmt":"2012-06-27T17:30:06","slug":"thomas-alva-would-be-proud","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/thomas-alva-would-be-proud\/","title":{"rendered":"Thomas Alva Would Be Proud"},"content":{"rendered":"

The best batteries as now produced use expensive materials and processes to achieve high energy density.\u00a0 Could a century-old idea be resurrected to provide an inexpensive alternative to today\u2019s costly electric storage devices? \u00a0 Science Daily<\/em> <\/a>reports on a recent attempt to improve on a proven technology.<\/p>\n

Stanford University\u2019s Hongjie Dai, professor of chemistry and head of a research group, is working with the Edison battery, named for Thomas Alva Edison, and using the nickel-iron electrodes Edison favored, but with a modern twist to overcome one of its disadvantages.<\/p>\n

Stanford\u2019s news bulletin quotes Dai.\u00a0 “The Edison battery is very durable, but it has a number of drawbacks. A typical battery can take hours to charge, and the rate of discharge is also very slow.”<\/p>\n

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Stanford's approach to improving the Edison battery<\/p><\/div>\n

Powering electric vehicles in the early 1900s, Edison\u2019s battery is used today in limited instances to store surplus electricity from solar panels and wind turbines where charging and discharge speeds are not a major consideration.\u00a0 Dai\u2019s group started with graphene sheets and 10 nested carbon nanotubes \u2013 and \u201cgrew\u201d nanocrystals of iron oxide onto the graphene and nanocrystals of nickel hydroxide onto the carbon nanotubes.<\/p>\n

Edison\u2019s original nickel cathode and iron anode, meant to replace more expensive lead-acid batteries, is now graced with modern nanotechnology and reacts much faster than the original.\u00a0 Science Daily reports, \u201cThe Stanford team has created an ultrafast nickel-iron battery that can be fully charged in about 2 minutes and discharged in less than 30 seconds. The results are published in the June 26 issue of the journal Nature Communications<\/a><\/em>.<\/p>\n

“\u2019We have increased the charging and discharging rate by nearly 1,000 times,\u2019 said Stanford graduate student Hailiang Wang, lead author of the study. \u2018We’ve made it really fast.\u2019”<\/p>\n

“\u2019Coupling the nickel and iron particles to the carbon substrate allows electrical charges to move quickly between the electrodes and the outside circuit,\u2019 Dai said. \u2018The result is an ultrafast version of the nickel-iron battery that’s capable of charging and discharging in seconds.\u2019”<\/p>\n

For now, the prototype one-Volt battery can light a small flashlight, but researchers hope to scale that to Nissan Leaf and Chevrolet Volt, or even to power grid size.\u00a0 Several issues might restrain it from becoming the budget salvation of EVs, however.<\/p>\n

Wang added, “\u2019Our battery probably won’t be able to power an electric car by itself, because the energy density is not ideal, but it could assist lithium-ion batteries by giving them a real power boost for faster acceleration and regenerative braking.\u2019”\u00a0 The battery also lacks cycle life, dropping 20 percent in capacity after 800 charge\/discharge \u201cround trips\u201d.\u00a0 \u00a0Combining the battery\u2019s low-cost ingredients with existing lithium chemistries may forge a hybrid cell that could exploit the advantages of both.<\/p>\n

Wang noted big plus in safety. “It’s definitely scalable \u00a0Nickel, iron and carbon are relatively inexpensive. And the electrolyte is just water with potassium hydroxide, which is also very cheap and safe. \u00a0It won’t blow up in a car.”<\/p>\n

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Professor Hongjie Dai's chemistry lab group<\/p><\/div>\n

Dai\u2019s group was featured in this blog for their work on \u201cunzipped\u201d carbon nanotubes<\/a>, another approach to reducing the cost of providing high energy density by replacing platinum catalysts in lithium batteries with lower cost carbon.<\/p>\n