Tuesday, April 24, 2012

Long Range Electric Car Batteries

If the Bugs Can Be Worked Out

IBM has a partnership with two Japanese chemical firms to develop a battery for cars with a 489 mile range, according to an April 20, 2012, article by Larry Greenemeier in Scientific American.  IBM has scheduled a working prototype for completion by the end of 2013.

The partners working with IBM since 2009 on this "IBM Battery 500 Project" are chemical firm Asahi Kasei Corporation and electrolyte manufacturer Central Glass.

Current lithium ion batteries use a metal oxide or metal phosphate cathode, particularly cobalt, manganese or iron-based, as the positive electrode and an anode based on carbon. An electrolyte fluid conducts lithium ions from one electrode to the other, flowing from the anode to the cathode while in use, through the electrode and a separator membrane. The flow is reversed when charging the battery. This will propel an electric vehicle only about 99 miles before exhausting the power, and some plug-in hybrids have a range of only about 50 miles before the gasoline motor must supply the power.

The air breathing battery replaces heavy metal oxides from within the battery with oxygen collected from the atmosphere while the vehicle is moving, forming lithium peroxide for electrical current to power the motor. When charging, the oxygen is released back into the atmosphere. In this design, a lithium anode is used. Sincd the battery has no heavy metal, it is very significantly lighter yet able to store more energy than a heavy-metal, lithium-ion battery.

A significant bottleneck in the air batteries is that the oxygen attacks and destroys the electrolyte, leaving it unable to conduct a charge. A suggestion by Winfried Wilcke, the project’s principal investigator, is to use one electrolyte for the cathode and a different electrolyte for the anode, with a membrane to keep the separate fluids from mixing. A project partner, Asahi Kasei, is developing such a membrane. Central Glass is creating a new group of electrolytes and high performance additives to increase the performance of lithium air batteries.

Wilcke estimates the lithium–air batteries might be ready for production by 2020 at the earliest, "if we don't find any show-stopping technology along the way." He adds: "The only thing I'm certain of is that it won't happen this decade."

An important way to compare batteries is to measure the specific energy of the device. Conventional lead-acid batteries produce 40 watt-hours per kilogram. The lithium-ion batteries in use in many present electric cars have a maximum of 250 watt-hours per kilogram. The potential for lithium-air batteries is above 1,400 watt-hours per kilogram. Wilcke says a larger prototype is needed to give a more accurate figure for lithium-air density, but he is working for 1,000 watt-hours per kilogram. Wilcke projects such batteries may be ready for production by 2020 if no technological barrier is discovered, but he also noted that he is certain such batteries will not be available in this decade.

The IBM partnership is not alone in pursuing this research. M.I.T. researchers are working on a lithium-air battery with carbon nanofiber electrodes and Yangchuan Xing of Missouri University of Science and Technology receivdd a $1.2 million Department of Energy award to develop lithium-air batteries.

Summarized from:


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It won’t be easy solving these technical issues. The above link includes a comment section. Comment 9 by "scudge" at 01:39 AM on April 21st, 2012, reads:
"propylene carbonate is too unstable even if you put oxooxazolidines for non aqueous electrolyte... acids, bases and salts all decompose it... carbon dioxide froth is all you'll end up with..."

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