Thursday, October 27, 2011

Argonne Making Sodium-ion Batteries Worth Their Salt

Although lithium-ion technology dominates headlines in battery research and development, a new element is making its presence known as a potentially powerful alternative: sodium.

Sodium-ion technology possesses a number of benefits that lithium-based energy storage cannot capture, explained Argonne National Labs chemist Christopher Johnson, who is leading an effort to improve the performance of ambient-temperature sodium-based batteries.

Perhaps most importantly, sodium is far more naturally abundant than lithium, which makes sodium lower in cost and less susceptible to extreme price fluctuations as the battery market rapidly expands.

"Our research into sodium-ion technology came about because one of the things we wanted to do was to cover all of our bases in the battery world," Johnson said. "We knew going in that the energy density of sodium would be lower, but these other factors helped us decide that these systems could be worth pursuing."

Argonne chemist Christopher Johnson holds a sodium-ion cathode.
Sodium ions are roughly three times as heavy as their lithium cousins, however, and their added heft makes it more difficult for them to shuttle back and forth between a battery's electrodes. As a result, scientists have to be more particular about choosing proper battery chemistries that work well with sodium on the atomic level.
While some previous experiments have investigated the potential of high-temperature sodium-sulfur batteries, Johnson explained that room-temperature sodium-ion batteries have only begun to be explored. "It's technologically more difficult and more expensive to go down the road of sodium-sulfur; we wanted to leverage the knowledge in lithium-ion batteries that we've collected over more than 15 years," he said.

Because of their reduced energy density, sodium-ion batteries will not work as effectively for the transportation industry, as it would take a far heavier battery to provide the same amount of energy to power a car. However, in areas like stationary energy storage, weight is less of an issue, and sodium-ion batteries could find a wide range of applications.

"The big concerns for stationary energy storage are cost, performance and safety, and sodium-ion batteries would theoretically perform well on all of those measures," Johnson explained.

All batteries are composed of three distinct materials—a cathode, an anode and an electrolyte. Just as in lithium-ion batteries, each of these materials has to be tailored to accommodate the specific chemical reactions that will make the battery perform at its highest capacity. "You have to pick the right materials for each component to get the entire system to work the way it's designed," Johnson said.

To that end, Johnson has partnered with a group led by Argonne nanoscientist Tijana Rajh to investigate how sodium ions are taken up by anodes made from titanium dioxide nanotubes. "The way that those nanotubes are made is very scalable—if you had large sheets of titanium metal, you can form the tubes in a large array," Johnson said. "That would then enable you to create a larger battery."

The next stage of the research, according to Johnson, would involve the exploration of aqueous, or water-based, sodium-ion batteries, which would have the advantage of being even safer and less expensive.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

Wednesday, October 26, 2011

Nearly 600 Energy Storage Projects Announced or Deployed

A new tracker report from Pike Research indicates that nearly 600 energy storage projects have been announced or deployed worldwide, with a surge of new project activity during the past decade.
"Energy storage offers the opportunity to significantly improve the efficiency of the grid at every level," says research analyst Anissa Dehamna.  "The energy storage market is dynamic, but still immature where most technologies are concerned.  The vast majority of active storage projects are utilizing decades-old pumped hydro storage technologies, but the industry has entered a new period of innovation as a number of market players invest considerable resources to prove emerging technologies such as advanced batteries, compressed air energy storage, flywheels, and thermal storage."

Dehamna adds that the wide variety of technologies, applications, and lead times for installations in this sector can make it difficult for many industry participants to analyze the overall market.  Pike Research's tracker aims to identify key market trends on a holistic basis by systematically compiling the available data on all projects around the world including analysis of site, region, size, status, duration, market segment, applications and funding profiles.

Pike Research's "Energy Storage Tracker" provides a comprehensive database of worldwide energy storage projects, including quantitative and qualitative analysis of key trends within the various application and technology segments.  The tracker provides key facts and figures for each project including capacity, location, primary and secondary applications, technologies utilized, and investment cost where available.

Tuesday, October 25, 2011

Energy Storage Industry Grows To Integrate Wind, Solar

By Robert Crowe, Contributor. Reprinted with permission from Renewable Energy World.

Grid-scale energy storage is gaining momentum as batteries, flywheels and compressed air systems begin proving they can regulate frequency and ancillary services with the same efficiency of "spinning reserves" from fossil fuel-fired power plants.

Monday, October 24, 2011

Electric Vehicle Batteries: New Report

Over the past few years, the automotive industry has increased its focus on the electric vehicle (EV) market by successfully introducing several new plug-in hybrid and battery electric vehicles as the process of moving away from petroleum based fuels and toward battery power intensifies. These vehicles will rely almost exclusively on lithium ion (Li-ion) batteries, while hybrid vehicles will slowly switch from nickel-metal hydride (NiMH) technology. While the cost of Li-ion batteries is gradually declining, cost still represents a significant hurdle as it accounts for a large portion of total EV cost.
The government subsidies that gave the initial impetus to the electric vehicle market will continue to drive the market in the near term. However, significant reductions in battery cost are imperative for the industry to grow to the $14.6 billion and 28 million kWh market that Pike Research forecasts by 2017. Nearly half of the demand is likely to come from Asia (led primarily by China) while Europe and the United States are likely to constitute 25% and 21% shares respectively.

There are currently more than half a dozen battery chemistries with unique properties for power, energy density, and life cycle performance that are being commercialized. While there is no chemistry that emerges as the clear winner (owing to the tradeoffs in the various properties), initial indications point to a greater interest in the lithium iron phosphate chemistry in the years to come due to its superior performance characteristics coupled with increased safety.

A new report from Pike Research outlines the critical role that governments around the globe will play in establishing the electric vehicle market, and the challenges that manufacturers face in creating an industry that will be able to stand on its own as government influence diminishes. The study examines the key market drivers for the electrification of vehicles, the status of the R&D in batteries, the impact of declining battery production costs on vehicle sales, and the resale of batteries after their useful life in vehicles.