Ni/Bi battery based on Ni(OH)2 nanoparticles/graphene sheets and Bi2O3 rods/graphene sheets with high performance

• Ni(OH)2/GS and Bi2O3/GS composite were synthesized respectively by simple methods.
• A novel Ni/Bi battery is assembled using Ni(OH)2/GS and Bi2O3/GS as electrode materials.
• The Ni/Bi battery exhibits a high capacity of 98 mA h g−1 at 1 C and energy density of 82.6 W h kg−1.

Two kinds of graphene-based composite materials of Ni(OH)2 nanoparticles/graphene sheets (Ni(OH)2/GS) and Bi2O3 rods/graphene sheets (Bi2O3/GS) were respectively synthesized by chemical bath deposition. Morphological and structural analysis by field-emission scanning electron microscopy, transmission electron microscope, X-ray diffraction and X-ray photoelectron spectroscopy confirmed the successful composite of GS with the metal compounds. Then, a high performance Ni/Bi battery was designed and fabricated using the Bi2O3/GS hybrid material as negative electrode and Ni(OH)2/GS as positive electrode. As a result, this Ni/Bi battery delivers a high discharge capacity of 102 mA h g−1 at 1 C and good rate capability. A high energy density of 83.2 W h kg−1 is also achieved at a power density of 143 W kg−1 and can still maintain a high level of 60.1 W h kg−1 at 2609 W kg−1, illustrating that this Ni/Bi battery is a promising candidate as energy storage devices.