TY - JOUR
T1 - Full Concentration Gradient-Tailored Li-Rich Layered Oxides for High-Energy Lithium-Ion Batteries
AU - Wu, Tianhao
AU - Liu, Xiang
AU - Zhang, Xu
AU - Lu, Yue
AU - Wang, Boya
AU - Deng, Qingsong
AU - Yang, Yubo
AU - Wang, Errui
AU - Lyu, Zhongtian
AU - Li, Yaoqian
AU - Wang, Yongtao
AU - Lyu, Yan
AU - He, Cunfu
AU - Ren, Yang
AU - Xu, Guiliang
AU - Sun, Xueliang
AU - Amine, Khalil
AU - Yu, Haijun
PY - 2021/1/14
Y1 - 2021/1/14
N2 - Lithium-rich layered oxides (LLOs) are prospective cathode materials for next-generation lithium-ion batteries (LIBs), but severe voltage decay and energy attenuation with cycling still hinder their practical applications. Herein, a series of full concentration gradient-tailored agglomerated-sphere LLOs are designed with linearly decreasing Mn and linearly increasing Ni and Co from the particle center to the surface. The gradient-tailored LLOs exhibit noticeably reduced voltage decay, enhanced rate performance, improved cycle stability, and thermal stability. Without any material modifications or electrolyte optimizations, the gradient-tailored LLO with medium-slope shows the best electrochemical performance, with a very low average voltage decay of 0.8 mV per cycle as well as a capacity retention of 88.4% within 200 cycles at 200 mA g−1. These excellent findings are due to spinel structure suppression, electrochemical stress optimization, and Jahn-Teller effect inhibition. Further investigation shows that the gradient-tailored LLO reduces the thermal release percentage by as much as about 41% when the battery is charged to 4.4 V. This study provides an effective method to suppress the voltage decay of LLOs for further practical utilization in LIBs and also puts forward a bulk-structure design strategy to prepare better electrode materials for different rechargeable batteries.
AB - Lithium-rich layered oxides (LLOs) are prospective cathode materials for next-generation lithium-ion batteries (LIBs), but severe voltage decay and energy attenuation with cycling still hinder their practical applications. Herein, a series of full concentration gradient-tailored agglomerated-sphere LLOs are designed with linearly decreasing Mn and linearly increasing Ni and Co from the particle center to the surface. The gradient-tailored LLOs exhibit noticeably reduced voltage decay, enhanced rate performance, improved cycle stability, and thermal stability. Without any material modifications or electrolyte optimizations, the gradient-tailored LLO with medium-slope shows the best electrochemical performance, with a very low average voltage decay of 0.8 mV per cycle as well as a capacity retention of 88.4% within 200 cycles at 200 mA g−1. These excellent findings are due to spinel structure suppression, electrochemical stress optimization, and Jahn-Teller effect inhibition. Further investigation shows that the gradient-tailored LLO reduces the thermal release percentage by as much as about 41% when the battery is charged to 4.4 V. This study provides an effective method to suppress the voltage decay of LLOs for further practical utilization in LIBs and also puts forward a bulk-structure design strategy to prepare better electrode materials for different rechargeable batteries.
KW - electrochemical stress
KW - full concentration gradient
KW - Li-ion batteries
KW - lithium-rich layered oxides
KW - voltage decay
UR - http://www.scopus.com/inward/record.url?scp=85096844512&partnerID=8YFLogxK
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-85096844512&origin=recordpage
U2 - 10.1002/adma.202001358
DO - 10.1002/adma.202001358
M3 - RGC 21 - Publication in refereed journal
C2 - 33251601
SN - 0935-9648
VL - 33
JO - Advanced Materials
JF - Advanced Materials
IS - 2
M1 - 2001358
ER -
