TY - JOUR
T1 - Exceptional Lithium Storage in a Co(OH)2 Anode
T2 - Hydride Formation
AU - Kim, Hyunchul
AU - Choi, Woon Ih
AU - Jang, Yoonjung
AU - Balasubramanian, Mahalingam
AU - Lee, Wontae
AU - Park, Gwi Ok
AU - Park, Su Bin
AU - Yoo, Jaeseung
AU - Hong, Jin Seok
AU - Choi, Youn Suk
AU - Lee, Hyo Sug
AU - Bae, In Tae
AU - Kim, Ji Man
AU - Yoon, Won Sub
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/3/27
Y1 - 2018/3/27
N2 - Current lithium ion battery technology is tied in with conventional reaction mechanisms such as insertion, conversion, and alloying reactions even though most future applications like EVs demand much higher energy densities than current ones. Exploring the exceptional reaction mechanism and related electrode materials can be critical for pushing current battery technology to a next level. Here, we introduce an exceptional reaction with a Co(OH)2 material which exhibits an initial charge capacity of 1112 mAh g-1, about twice its theoretical value based on known conventional conversion reaction, and retains its first cycle capacity after 30 cycles. The combined results of synchrotron X-ray diffraction and X-ray absorption spectroscopy indicate that nanosized Co metal particles and LiOH are generated by conversion reaction at high voltages, and CoxHy, Li2O, and LiH are subsequently formed by hydride reaction between Co metal, LiOH, and other lithium species at low voltages, resulting in a anomalously high capacity beyond the theoretical capacity of Co(OH)2. This is further corroborated by AIMD simulations, localized STEM, and XPS. These findings will provide not only further understanding of exceptional lithium storage of recent nanostructured materials but also valuable guidance to develop advanced electrode materials with high energy density for next-generation batteries.
AB - Current lithium ion battery technology is tied in with conventional reaction mechanisms such as insertion, conversion, and alloying reactions even though most future applications like EVs demand much higher energy densities than current ones. Exploring the exceptional reaction mechanism and related electrode materials can be critical for pushing current battery technology to a next level. Here, we introduce an exceptional reaction with a Co(OH)2 material which exhibits an initial charge capacity of 1112 mAh g-1, about twice its theoretical value based on known conventional conversion reaction, and retains its first cycle capacity after 30 cycles. The combined results of synchrotron X-ray diffraction and X-ray absorption spectroscopy indicate that nanosized Co metal particles and LiOH are generated by conversion reaction at high voltages, and CoxHy, Li2O, and LiH are subsequently formed by hydride reaction between Co metal, LiOH, and other lithium species at low voltages, resulting in a anomalously high capacity beyond the theoretical capacity of Co(OH)2. This is further corroborated by AIMD simulations, localized STEM, and XPS. These findings will provide not only further understanding of exceptional lithium storage of recent nanostructured materials but also valuable guidance to develop advanced electrode materials with high energy density for next-generation batteries.
UR - http://www.scopus.com/inward/record.url?scp=85044501605&partnerID=8YFLogxK
U2 - 10.1021/acsnano.8b00435
DO - 10.1021/acsnano.8b00435
M3 - Article
C2 - 29480713
AN - SCOPUS:85044501605
SN - 1936-0851
VL - 12
SP - 2909
EP - 2921
JO - ACS Nano
JF - ACS Nano
IS - 3
ER -
