Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=226575
Story Retrieval Date: 2/27/2015 12:00:09 AM CST
Eliza Grinnell/Harvard School of Engineering and Applied Sciences
New battery technology that Harvard researchers say could fundamentally alter energy storage, making wind and solar energy more economical, debuted in the current issue of the journal Nature.
Improved energy storage could stockpile energy from wind and solar plants for use when the wind doesn’t blow or the sun doesn’t shine.
The flow battery developed by a team of Harvard scientists can store immense amounts of energy in a three-component system using organic materials, they report.
Common batteries, such as car or phone batteries, work as a single, self-containted unit to store and deliver energy. Flow batteries, such as the one developed by the Harvard team, are composed of three units: one container storing the negative electrode as a chemical solution, another container storing the positive electrode as a chemical solution, and a central unit that controls the electrochemical reaction for the flow of energy.
Flow batteries increasingly are being used for renewable energy storage because they allow for larger amounts of energy to be stored at lower costs. The components allow for larger energy storage capacity for industrial applications.
Many flow batteries contain metal ions in their chemical solutions. The flow battery developed by the Harvard team is different because its chemical solution contains quinones instead of metals. Quinones are natural, carbon-based molecules that can be found in crude oil and green plants.
Roy Gordon, professor of chemistry and materials science and a researcher on the Harvard team, said the problem with metal-based battery technology is that “either there isn’t enough metals, or they’re toxic.” Quinones, on the other hand, are abundant and organic.
“The initial data they’re showing looks like it’s worth exploring,” said Andrew Jansen, a principle chemical engineer at Argonne National Laboratory. “It’ll really be a question of if they can demonstrate reliability over thousands of cycles.”
Argonne is also doing research on non-metal battery technology, but with non-quinone species, through the Joint Center for Energy Storage Research. The program at JCER is developing a battery with the goal to store five times the amount of energy of traditional batteries, at one-fifth the cost and within five years.
The research is identifying and innovating new materials to accomplish this “5-5-5” goal, which could provide high-powered, compact batteries for electric cars and the energy grid. The program began in 2012.
“This would set the benchmark,” said Jansen.
However, members of the wind energy community are skeptical of the financial benefits of improved battery technology for the wind industry.
Michael Goggin, a senior electric industry analyst at the American Wind Energy Association, said energy storage is not a large concern in the wind community right now.
“It’s not a limiting factor for the foreseeable future,” he said. “Wind is being reliably integrated onto the grid today. Wind energy never changes that much. I think it’s a bit of a misplaced concern.”
Because generating plants that use fossil fuels fill the gap, Goggin said he believes improved storage technology will be important only “in the very distant future when we’re getting most of our energy from wind energy and solar energy. But that’s a very long way from where we are today.”
Instead, Goggin said there should be a greater focus on laws and rules that currently stand in the way of efficient grid-operating procedures.
Whether new energy storage technology proves critical to the renewable energy industry in the future or not, Gordon remains optimistic about the development of organic flow battery technology. With funding from the Department of Energy, the Harvard team expects to have a commercially viable version of their battery available within three years.
“It is really extraordinary that the team has accomplished so much in such a short time,” he said.