In a traditional Li-ion battery cell, positively charged lithium ions migrate through a liquid electrolyte, while electrons flow through an external circuit, both moving back and forth from one side to the other. This movement creates and stores energy. Li-ion batteries have been a success for small, mobile electronics such as cell phones and laptop computers, but making them larger is difficult because they are expensive, prone to overheating and can lend themselves to electrical shorting. Scientists say while substantial progress has been made over past years to improve the technology, more work must be done to extend life, improve safety and reduce materials cost for the stationary applications.
Lead-Carbon Battery
Lead-carbon batteries are an evolving technology born from the traditional lead-acid battery, commonly used for traditional automobiles and back-up generators. Scientists have found by adding a bit of carbon to traditional lead-acid batteries they can significantly increase the life-span of the battery. Researchers say lead-carbon batteries could serve as a viable back-up source for wind and solar power because of their concentrated power.
During discharge in a traditional lead-acid battery, sulfuric acid reacts with the lead anode and cathode to create lead sulfate. The process reverses during charge. This conversion produces a short, powerful burst of energy, such as needed to jump start a vehicle. But over time, a lead-acid battery can lose its charge due to the gradual crystallization and buildup of lead sulfate within the battery’s core. The corrosive acid also can eat away at a battery’s core.
Adding carbon to the battery seems to minimize or prevent this crystallization from occurring, improving the cycle life and overall life-span of the battery. Researchers say this technology has potential for storing renewable energy but that more field work is needed to understand the limitations – and to find ways to bring down the cost. The capital cost of the technology remains at $ 500 per-kilowatt hour and they believe it needs to be reduced to between $ 150-$ 200 per-kilowatt hour to be viable.
The Department of Energy’s Offices of Electricity Delivery and Energy Reliability, Energy Efficiency and Renewable Energy, and Advanced Research Projects Agency-Energy (ARPA-E), as well as PNNL’s Laboratory Directed Research and Development Fund, supported this work.
Check the following link for Full Report:
http://pubs.acs.org/doi/abs/10.1021/cr100290v
About PNNL
Pacific Northwest National Laboratory (PNNL) is a Department of Energy Office of Science national laboratory where inter-disciplinary teams advance science and technology and deliver solutions to America’s most intractable problems in energy, the environment and national security. PNNL employs 4,900 staff, has an annual budget of nearly $ 1.1 billion, and has been managed by Ohio-based Battelle since the lab’s inception in 1965. For more information, visit www.pnl.gov.
Source: PNNL Press Release dated March 7, 2011.
