A flexible alkaline rechargeable Ni/Fe battery based on graphene foam/carbon nanotubes hybrid film.
The development of portable and wearable electronics has promoted increasing demand for high-performance power sources with high energy/power density, low cost, lightweight, as well as ultrathin and flexible features. Here, a new type of flexible Ni/Fe cell is designed and fabricated by employing Ni(OH)2 nanosheets and porous Fe2O3 nanorods grown on lightweight graphene foam (GF)/carbon nanotubes (CNTs) hybrid films as electrodes. The assembled f-Ni/Fe cells are able to deliver high energy/power densities (100.7 Wh/kg at 287 W/kg and 70.9 Wh/kg at 1.4 kW/kg, based on the total mass of active materials) and outstanding cycling stabilities (retention 89.1% after 1000 charge/discharge cycles). Benefiting from the use of ultralight and thin GF/CNTs hybrid films as current collectors, our f-Ni/Fe cell can exhibit a volumetric energy density of 16.6 Wh/l (based on the total volume of full cell), which is comparable to that of thin film battery and better than that of typical commercial supercapacitors. Moreover, the f-Ni/Fe cells can retain the electrochemical performance with repeated bendings. These features endow our f-Ni/Fe cells a highly promising candidate for next generation flexible energy storage systems.
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , 637371, Singapore.
Jilei
J
Liu
Minghua
M
Chen
Lili
L
Zhang
Jian
J
Jiang
Jiaxu
J
Yan
Yizhong
Y
Huang
Jianyi
J
Lin
Hong Jin
HJ
Fan
Ze Xiang
ZX
Shen
Ni/Fe cell; carbon nanotubes; flexible battery; graphene foam; hybrid electrodes