Accelerated Development of High Voltage Li‐Ion Cathodes
Antranik Jonderian, Shipeng Jia, Gabin Yoon, Victor Cozea, Nooshin Zeinali Galabi, Sang Bok, Eric McCalla
Abstract
Abstract High voltage cathodes are attractive for high energy density Li‐ion batteries. However, candidates such as LiCoPO 4 have presented numerous challenges stemming from poor electronic/ionic conductivities such that typical solutions involving nanosizing result in extremely poor cycling performance. Here, high‐throughput methods are applied to develop near‐micron sized carbon‐coated LiCoPO 4 with improved energy density and capacity retention. In total, 1300 materials with 46 different substituents are synthesized and characterized. A number of substituents show greatly improved capacity (e.g., 160 mAh g −1 for 1% indium (In) substitution vs 95 mAh g −1 for the pristine). However, co‐doping is required to improve extended cycling. Li 1–3x Co 1–2x In x Mo x PO 4 is found to be particularly effective with dramatically improved cycling (as high as 100% after 10 cycles, vs ≈50% in unsubstituted). While In improves the electronic conductivity of the carbon‐coated materials, molybdenum (Mo) co‐doping gives larger particles. DFT calculations show that Mo impedes the formation of Li/Co antisite defects.