Low Cost Synthesis of High Surface Area Thermally Stable Lithium-Ion Battery Cathodes
DOE Phase I Contract DE-FG02-05ER84229
Phosphate compounds have significant potential as the next generation cathode in secondary lithium-ion batteries. The inclusion of these compounds in electric vehicle and hybrid vehicle applications is dependant on increasing the surface area of the cathode active material for increased capacity, and development of new materials that are thermally stable to overcharge situations and thermal runaway.
Two lithium vanadium phosphates will be prepared as high capacity, thermally stable cathode materials. The vanadium oxygen double bond in lithium vanadyl phosphate and the corner sharing phosphate tetrahedra in lithium vanadium di-phosphate are expected to make these two phosphates more thermally stable than current phosphate based lithium-ion cathodes.
In this DOE SBIR Phase I project a novel synthesis method developed by Eltron Research, Inc. will be used to prepare high surface area thermally stable lithium vanadium phosphate compounds for lithium-ion battery cathodes. The prepared compounds will be characterized with X-ray diffraction, Scanning Electron Microscopy, and surface area analysis. Differential Scanning Calorimetry will be used to verify thermal stability and cathode specific capacity will be determined by constructing and testing lithium-ion battery coin cells.
Batteries represent a $50 billion world wide market. The market for secondary (rechargeable) batteries is $5.5 billion. Lithium iron phosphate compounds are beginning to be commercialized as rechargeable battery cathodes for portable electronics. Cathode materials based on phosphates are environmentally friendly and possess the capacity and cycling stability necessary for portable electronics. Phosphate based materials also have significant commercial potential as battery materials for electric and hybrid vehicles if the safety of these materials with respect to overcharge and thermal runaway can be addressed. Advancement of battery technology will benefit the public in the form of reduced dependence on foreign oil and reduced harmful emission from vehicles.