TY - JOUR
T1 - Lithium-ion capacitors with 2D Nb2CTx (MXene) – carbon nanotube electrodes
AU - Byeon, Ayeong
AU - Glushenkov, Alexey M.
AU - Anasori, Babak
AU - Urbankowski, Patrick
AU - Li, Jingwen
AU - Byles, Bryan W.
AU - Blake, Brian
AU - Van Aken, Katherine L.
AU - Kota, Sankalp
AU - Pomerantseva, Ekaterina
AU - Lee, Jae W.
AU - Chen, Ying
AU - Gogotsi, Yury
N1 - Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/9/15
Y1 - 2016/9/15
N2 - There is a growing interest to hybrid energy storage devices, such as lithium-ion capacitors, in which battery-type electrodes are combined with capacitor-type ones. It is anticipated that the energy density (either gravimetric or volumetric) of lithium-ion capacitors is improved if pseudocapacitive or fast insertion materials are used instead of conventional activated carbon (AC) in the capacitor-type electrode. MXenes, a new family of two-dimensional transition metal carbides, demonstrate metallic conductivity and fast charge-discharge behavior that make them suitable for this application. In this study, we move beyond single electrodes, half-cell studies and demonstrate three types of hybrid cells using Nb2CTx–carbon nanotube (CNT) films. It is shown that lithiated graphite/Nb2CTx-CNT, Nb2CTx-CNT/LiFePO4 and lithiated Nb2CTx-CNT/Nb2CTx-CNT cells are all able to operate within 3 V voltage windows and deliver capacities of 43, 24 and 36 mAh/g (per total weight of two electrodes), respectively. Moreover, the polarity of the electrodes can be reversed in the symmetric Nb2CTx-CNT cells from providing a positive potential between 0 and 3 V to a negative one from −3 to 0 V. It is shown that the volumetric energy density (50–70 Wh/L) of our first-generation devices with MXene electrodes exceeds that of a lithium titanate/AC capacitor.
AB - There is a growing interest to hybrid energy storage devices, such as lithium-ion capacitors, in which battery-type electrodes are combined with capacitor-type ones. It is anticipated that the energy density (either gravimetric or volumetric) of lithium-ion capacitors is improved if pseudocapacitive or fast insertion materials are used instead of conventional activated carbon (AC) in the capacitor-type electrode. MXenes, a new family of two-dimensional transition metal carbides, demonstrate metallic conductivity and fast charge-discharge behavior that make them suitable for this application. In this study, we move beyond single electrodes, half-cell studies and demonstrate three types of hybrid cells using Nb2CTx–carbon nanotube (CNT) films. It is shown that lithiated graphite/Nb2CTx-CNT, Nb2CTx-CNT/LiFePO4 and lithiated Nb2CTx-CNT/Nb2CTx-CNT cells are all able to operate within 3 V voltage windows and deliver capacities of 43, 24 and 36 mAh/g (per total weight of two electrodes), respectively. Moreover, the polarity of the electrodes can be reversed in the symmetric Nb2CTx-CNT cells from providing a positive potential between 0 and 3 V to a negative one from −3 to 0 V. It is shown that the volumetric energy density (50–70 Wh/L) of our first-generation devices with MXene electrodes exceeds that of a lithium titanate/AC capacitor.
KW - Carbon nanotube
KW - Lithium-ion capacitors
KW - MXene
KW - Niobium carbide
KW - Two-dimensional materials
UR - http://www.scopus.com/inward/record.url?scp=84964374869&partnerID=8YFLogxK
U2 - 10.1016/j.jpowsour.2016.03.066
DO - 10.1016/j.jpowsour.2016.03.066
M3 - Article
SN - 0378-7753
VL - 326
SP - 686
EP - 694
JO - Journal of Power Sources
JF - Journal of Power Sources
ER -