Lithium-ion batteries (LIB) have been receiving extensive attention because of the high specific energy density for wide applications such as electronic vehicles, commercial mobile electronics, and military applications. In LIB, graphite is the most commonly used anode material; however, lithium-ion intercalation in graphite is limited, hindering the battery charge rate and capacity. To overcome this obstacle, nanostructured anode assembly has been extensively studied to increase the lithium-ion diffusion rate. Among these approaches, high specific surface area metal oxide nanowires connecting nanostructured carbon materials accumulation have shown propitious results for enhanced lithium intercalation. Recently, nanowire/graphene hybrids were developed for the enhancement of LIB performance; however, almost all previous efforts employed nanowires on graphene in a random fashion, which limited lithium-ion diffusion rate. Therefore, we demonstrate a new approach by hydrothermally growing uniform nanowires on graphene aerogel to further improve the performance. This nanowire/graphene aerogel hybrid not only uses the high surface area of the graphene aerogel but also increases the specific surface area for electrode-electrolyte interaction. Therefore, this new nanowire/graphene aerogel hybrid anode material could enhance the specific capacity and charge-discharge rate. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used for materials characterization. Battery analyzer and potentio-galvanostat are used for measuring the electrical performance of the battery. The testing results show that nanowire graphene hybrid anode gives significantly improved performance compared to graphene anode.

Actual conversion based on AgO is 70% since some Ag + and Ag ~ remain during charging to Ag + +. Therefore 1.4 X 70% ~ 0.98 A-hr is actually expected to force discharge 1.0g of fully charged silver. Testing commences by charging at a 5 hr rate until oxygen evolution. The charging current is decreased to 25 hr rate until oxygen evolution once again occurs.Currents would be 0.98 A-hr = 0.196A~5 hr rate charge 5 hr 0.98 A-hr --= 0.039A--25 hr rate charge 25hrTesting continues by discharging at a 1 hr rate until hydrogen evolution 0.98 A-hr 0.98A discharge 1 hr Note that the discharge time is such that, in 1 hr, 70% efficiency based on Ag ++ would be achieved. Theoretically, the longest discharge would be 1.4 A-hr• 60 ~ 85.8 rain at the 1 hr rate 0.98A

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