Na-rich layered Na2Ti1-xCrxO3-x/2(x = 0, 0.06): Na-ion battery cathode materials with high capacity and long cycle life.
Rechargeable lithium batteries have been well-known and indispensable for portable electronic devices, and have the potential to be used in electric vehicles and smart grids. However, the growing concerns about the availability of lithium resources for large-scale applications have revived interest in sodium ion batteries. Of many obstacles to commercialization of Na-ion batteries, achieving simultaneously a large reversible capacity and good cycling capability of electrode materials remains a major challenge. Here, we report a new cathode material, Na-rich layered oxide Na2Ti0.94Cr0.06O2.97, that delivers high reversible capacity of 336 mAh g-1at current density of 18.9 mA g-1along with promising cycling capability of 74% capacity retention over 1000 cycles at current of 378 mA g-1. The high capacity is associated to the redox reaction of oxygen, which is confirmed here by a combined experimental and theoretical study. The present work therefore shows that materials beyond mainstream layered oxides and polyanion compounds should be considered as candidate high-performance cathodes for Na-ion batteries.
College of Aerospace Engineering, Chongqing University, Chongqing, 400044, P.R. China. sfsong@cqu.edu.cn.
Shufeng
S
Song
Materials Science Group, Department of Mechanical Engineering, National University of Singapore, Singapore, 117575, Singapore.
Masashi
0000-0001-7335-3833
M
Kotobuki
Materials Science Group, Department of Mechanical Engineering, National University of Singapore, Singapore, 117575, Singapore.
Yingqian
Y
Chen
Materials Science Group, Department of Mechanical Engineering, National University of Singapore, Singapore, 117575, Singapore.
Sergei
S
Manzhos
College of Aerospace Engineering, Chongqing University, Chongqing, 400044, P.R. China.
Chaohe
C
Xu
College of Aerospace Engineering, Chongqing University, Chongqing, 400044, P.R. China. ninghu@cqu.edu.cn.|The State Key Laboratory of Mechanical Transmissions, Chongqing University, Chongqing, 400044, P.R. China. ninghu@cqu.edu.cn.
Ning
N
Hu
Materials Science Group, Department of Mechanical Engineering, National University of Singapore, Singapore, 117575, Singapore. luli@nus.edu.sg.|National University of Singapore Suzhou Research Institute, Suzhou, P.R. China. luli@nus.edu.sg.
Li
L
Lu