| Title | Dissociate lattice oxygen redox reactions from capacity and voltage drops of battery electrodes |
| Authors | Wu, Jinpeng Zhuo, Zengqing Xiaohui, Rong Dai, Kehua Lebens-Higgins, Zachary Sallis, Shawn Pan, Feng Piper, Louis F. J. Liu, Gao Chuang, Yi-de Hussain, Zahid Li, Qinghao Zeng, Rong Shen, Zhi-xun Yang, Wanli |
| Affiliation | Stanford Univ, Geballe Lab Adv Mat, Stanford, CA 94305 USA Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA SLAC Natl Accelerator Lab, Stanford Inst Mat & Energy Sci, Menlo Pk, CA 94025 USA Peking Univ, Sch Adv Mat, Shenzhen Grad Sch, Shenzhen 518055, Peoples R China Univ Chinese Acad Sci, Chinese Acad Sci, Sch Phys Sci, Key Lab New Energy Mat & Devices,Inst Phys, Beijing 100190, Peoples R China Northeastern Univ, Sch Met, Shenyang 110819, Peoples R China Binghamton Univ, Dept Phys Appl Phys & Astron, Binghamton, NY 13902 USA Lawrence Berkeley Natl Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA Tsinghua Univ, Dept Elect Engn, Beijing 100084, Peoples R China Stanford Univ, Dept Phys & Appl Phys, Stanford, CA 94305 USA |
| Keywords | OXIDE CATHODE MATERIALS ANIONIC REDOX LAYERED OXIDES RICH CATHODE LI EVOLUTION RELEASE STATES CHALLENGES NMC |
| Issue Date | Feb-2020 |
| Publisher | SCIENCE ADVANCES |
| Abstract | The oxygen redox (OR) activity is conventionally considered detrimental to the stability and kinetics of batteries. However, OR reactions are often confused by irreversible oxygen oxidation. Here, based on high-efficiency mapping of resonant inelastic x-ray scattering of both the transition metal and oxygen, we distinguish the lattice OR in Na-0.6[Li0.2Mn0.8]O-2 and compare it with Na-2/3[Mg1/3Mn2/3]O-2. Both systems display strong lattice OR activities but with distinct electrochemical stability. The comparison shows that the substantial capacity drop in Na-0.6[Li0.2Mn0.8]O-2 stems from non-lattice oxygen oxidations, and its voltage decay from an increasing Mn redox contribution upon cycling, contrasting those in Na-2/3[Mg1/3Mn2/3]O-2. We conclude that lattice OR is not the ringleader of the stability issue. Instead, irreversible oxygen oxidation and the changing cationic reactions lead to the capacity and voltage fade. We argue that lattice OR and other oxygen activities should/could be studied and treated separately to achieve viable OR-based electrodes. |
| URI | http://hdl.handle.net/20.500.11897/586030 |
| ISSN | 2375-2548 |
| DOI | 10.1126/sciadv.aaw3871 |
| Indexed | SCI(E) Scopus EI |
| Appears in Collections: | 新材料学院 |
