A Quicker Test for Hybrid Batteries

Promising battery technologies often get bogged down in long experiments--a new test could set them loose.

It takes years to verify that a new battery technology will last for the life of a hybrid or electric car. That means battery materials that might cost less and store more energy than today's batteries are languishing on lab benches.

A new way to test lithium-ion batteries could cut that time to a few weeks instead of a few years, eliminating a key bottleneck that's keeping battery costs high and storage capacities low.

By accurately measuring how efficiently experimental batteries store and deliver an electrical charge, Jeff Dahn of Dalhousie University can predict how many times battery cells can be charged and discharged--known as the cycle life of the battery. Dahn, a professor of physics and chemistry, is also trying to demonstrate that the method can predict how long a battery will last on the shelf--known as calendar life.

Together, cycle life and calendar life determine how long a battery will be useful. They're essential for determining, for example, how big the battery pack needs to be to store the advertised amount of energy throughout the life of the car.

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The technique has caught the attention of automakers, which are trying to validate and use it, particularly as a tool for predicting cycle life. It could also allow academics, who have fewer resources than automakers, to develop battery materials with real commercial potential. "We think this technique could be very useful," says Masaki Matsui, manager of the materials research department at Toyota Research Institute of North America. He says it will identify problems with materials very early in battery development, allowing researchers to quickly sort through combinations of battery electrodes and electrolytes.

A panoply of things can go wrong in a battery. The key insight of Dahn's approach is that many such snags can show up in a single test--the measurement of the difference between the amount of charge that goes into a battery during charging and the amount that comes out when it's discharged (also called coulombic efficiency). If less charge comes out than goes in, that energy is being wasted by unwanted reactions within the battery. These losses add up: with successive cycles, the battery returns less and less charge until eventually it isn't usable.

A new chemical trick for making nanostructured materials

A new chemical trick for making nanostructured materials could help increase the range and reliability of electric cars and lead to better batteries that could help stabilize the power grid.

Researchers at the Pacific Northwest National Laboratory (PNNL) in Richland, WA, have developed the technique, which can turn a potential electrode material that cannot normally store electricity into one that stores more energy than similar battery materials already on the market.

In work published in the journal Nano Letters, the PNNL researchers show that paraffin wax and oleic acid encourages the growth of platelike nanostructures of lithium-manganese phosphate. These "nanoplates" are small and thin, allowing electrons and ions (atoms or molecules with a positive or negative charge) to move in and out of them easily. This turns the material--which ordinarily doesn't work as a battery material because of its very poor conductivity--into one that stores large amounts of electricity.

When the researchers measured the performance of the material, they discovered that it could store 10 percent more energy than the theoretical maximum energy capacity of a comparable commercial electrode material--lithium-iron phosphate, which is used in power tools and some hybrid and electric vehicles.

The approach could open the door to using a wide range of candidate battery materials that are now limited by their ability to conduct electricity and lithium ions. Research in the area has reached the point at which most of the battery materials left to be studied have bad conductivity, says Daiwon Choi, an energy materials researcher at PNNL. The new method provides a simple way to increase their conductivity. He says the method could also be compatible with conventional battery-manufacturing techniques.

Both lithium-iron phosphate and lithium-manganese phosphate are attractive at battery electrodes because they have a stable atomic structure. This crystalline structure--called olivine--is far more stable than the crystal structure of electrode materials used in laptop and cell-phone batteries. As a result, olivine materials can last much longer than the three years that cell-phone battery materials typically last. Some manufacturers claim that lithium-iron phosphate batteries could last for over 30,000 complete charge and discharge cycles without losing much of their capacity to store energy--enough for the battery to last 50 years.

Welcome to ILBF CHINA 2011 -- the 8th International Lead Battery Fair

Thanks for the support from the exhibitors & delegates from over 50+ countries, and thanks for the participants of traders, buyers & visitors concerned worldwide, the previous seven events of the ‘International Lead Battery Fair’ ---- ILBF CHINA 2009, ILBF CHINA 2007, ILBF CHINA 2005, ILBF CHINA 2004, ILBF CHINA 2002, ILBF CHINA 2000 & ILBF CHINA 1998 have been held in Beijing China & have been the great success.

Up to now, after the previous seven events in the last years, the ILBF CHINA has been the largest trade fair in the lead battery industry, and became the regular grand gathering of the manufacturers, suppliers, traders, buyers & all people concerned with business of lead batteries worldwide:

--- For all buyers & traders of lead batteries worldwide, the ILBF CHINA has been the best place to meet with all lead battery manufacturers in Asia for sourcing qualified automotive, motorcycle, motive power & sealed VRLA batteries;
--- For all lead battery manufacturers worldwide, the ILBF CHINA has been the best place to meet with all suppliers worldwide for purchasing advanced equipment, materials & components.

According to the timetable of the main events in battery industry worldwide, the organizers have planned to hold the 8th International Lead Battery Fair in the year of 2011.