Accelerated Development of High Voltage Li‐Ion Cathodes. Issue 40 (1st September 2022)

• Record Type: Journal Article
• Authors: Jonderian, Antranik; Jia, Shipeng; Yoon, Gabin; Cozea, Victor Teodor; Galabi, Nooshin Zeinali; Ma, Sang Bok; McCalla, Eric
• Is Part Of: Advanced energy materials. Volume 12:Issue 40(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-01
• Subjects: combinatorial synthesis and electrochemistry -- density functional theory calculations -- high voltage cathodes for Li‐ion batteries -- high‐throughput screening -- X‐ray diffraction; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202201704
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: High voltage cathodes are attractive for high energy density Li‐ion batteries. However, candidates such as LiCoPO4 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 LiCoPO4 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. Li1–3x Co1–2x Inx Mox PO4 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. Abstract : The performance of a high‐voltage Li‐ion cathode, LiCoPO4, is systematically improved through high‐throughput experimentation wherein doping and co‐doping are performed on the Co site. Low‐level doping of indium (1%) and a second dopant (e.g., Mo, Nb) show the best performance for both energy density and extended cycling. The reasons for the improvements are explored with computations and experiments.