摘要
The O3-type layered oxide cathodes for sodium-ion batteries(SIBs)are considered as one of the most promising systems to fully meet the requirement for future practical application.However,fatal issues in several respects such as poor air stability,irreversible complex multiphase evolution,inferior cycling lifespan,and poor industrial feasibility are restricting their commercialization development.Here,a stable Co-free O3-type NaNi_(0.4)Cu_(0.05)Mg_(0.05)Mn_(0.4)Ti_(0.1O2) cathode material with large-scale production could solve these problems for practical SIBs.Owing to the synergetic contribution of the multielement chemical substitution strategy,this novel cathode not only shows excellent air stability and thermal stability as well as a simple phase-transition process but also delivers outstanding battery performance in half-cell and full-cell systems.Meanwhile,various advanced characterization techniques are utilized to accurately decipher the crystalline formation process,atomic arrangement,structural evolution,and inherent effect mechanisms.Surprisingly,apart from restraining the unfavorable multiphase transformation and enhancing air stability,the accurate multielement chemical substitution engineering also shows a pinning effect to alleviate the lattice strains for the high structural reversibility and enlarges the interlayer spacing reasonably to enhance Na^(+)diffusion,resulting in excellent comprehensive performance.Overall,this study explores the fundamental scientific understandings of multielement chemical substitution strategy and opens up a new field for increasing the practicality to commercialization.
基金
This work was supported by the National Postdoctoral Program for Innovative Talents(BX20200222)
National Natural Science Foundation of China(Grant Nos.51772301,21878195,21805198,and 21805018)
the National Key R&D Program of China(Grant Nos.2016YFA0202500 and 2017YFB0307504)
the Distinguished Youth Science Foundation of Sichuan University(Grant 2017SCU04A08)
the Distinguished Youth Foundation of Sichuan Province(Grant No.2020JDJQ0027)
the Key R&D Program of Sichuan Province(Grant No.2020YFG00022)
the Library of Innovation Spark Project of Sichuan University(Grant No.2018SCUH0094)
the College-Enterprise Cooperation Project of Sichuan University(Grant Nos.19H0628 and 18H0357).