## 5 Applications
### Energy Storage
& & & \\ \hline \multirow{4}{*}{Plasma assisted ball} & 50:1 ratio of ball ( stainless steel) to & & & \\  & powder ratio in argon atmosphere used & & & \\  & in milling. The cylinder of ball milled & Potassium-ion & & \\  & vibrated with kHz frequency, 60 kHz & batteries (PTBs) & & \\  & discharge frequency with 1.5 \(A\) current & & & \\  & is applied during milling process. & & & \\ \hline \multirow{4}{*}{Ball Milling} & Lithium sulfate (Li\({}_{3}\)SO\({}_{4}\)) and Sodium & & & \\  & sulfate (Na\({}_{3}\)SO\({}_{4}\)) salts were ball milled & & & \\  & using stainless steel balls. 1.5 \(b\) ball to & & & \\  & powder ratio with different milling time & storage & & \\ \cline{1-1}  & &  
\begin{table} \begin{tabular}{l l l l l l} \hline \hline
**Type of Ball Milling** & **Specification** & **Battery/Supercapacitor** & **Highlights** & **Ref.** \\ \hline Dielectric barrier & Commercial germanium (Ge) and & & & & The nanocomposite prepared by Ce NVs (150 nm) wrapped with few-layer \\ discharge plasma & graphite (C) powders in 1:1 mass ratio, & & & graphene sheets (10 layers) (Ge@FELG) \\ assisted milling & steel ball powder ratio of \(\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{       }}}}}}}}}}}}}\) in (P-milling) & & & Ge@FELG composite anode showed nearly 90 \(\Omega\) of charge transfer resistance & [40] \\ \(\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{\bar{    \bar{     }}}}}}}}}}}}}}\) in (P-milling) & argon atmosphere & & & Ge@FELG composite exhibited 846.3 mA h g\({}^{-1}\) of capacity with 86\% of retention. & \\ \hline Dielectric barrier & Sn powder and graphite in 1:1 ratio, ball & & & Electrochemical performance of plasma assisted Sn-C composite (anode material) milled for 10 h showed 61.8\% of initial coulombic efficiency and 818.7 mA h g\({}^{-1}\) of initial capacity & [129] \\ assisted milling & & & & \\ (P-milling) & & & & The retention capacity with 385 mA h g\({}^{-1}\) supported up to 40 cycles & \\ \hline \hline \end{tabular}  \end{tableThus, ball milling is a versatile technique that can handle various elements, gives an easy approach to tailor the composition of nanocomposites, and produces defect-generated nanomaterials that aid in boosting the performance of devices as tabulated in Table 2.  
Hydrogen is a clean fuel. The present hydrogen economy has targeted hydrogen production and storage as key challenges. If hydrogen can be successfully stored within materials, then hydrogen on release can function as a clean fuel. In 2005, [PERSON] et al. [116] reported the hydrogen storage ability of the nano sized magnesium crystallites and MgH\({}_{2}\) (as received) ball milled with and without benzene (organic additives). The H\({}_{2}\) storage ability was tested by doping aluminum and nickel in MgH\({}_{2}\) sample. The hydrogen storage capacity of ball milled samples showed that the as-received MgH\({}_{2}\) milled with benzene > milled MgH\({}_{2}\) > Mg milled with benzene > milled Mg. Ball milled MgH\({}_{2}\) sample further doped with 1 at.%, and 2.9 at.% Al and Ni, respectively, in benzene showed the satisfactory hydrogen storage and hydriding/dehydriding performance. The maximum reversible hydrogen absorption capacity of 7.3 wt.% was achieved by 1 at.% Al-doped sample than Ni doped sample in H\({}_{2}\) atmosphere at 0.1 MPa pressure. A composite of nano silicon and graphene nanosheets (Nano-Si/GNs) prepared by discharged plasma assisted milling was employed as anode of lithium-ion batteries. The synergistic effect by fast heating discharge plasma and impact of milling led to the formation of nanostructure composite. In this composite, nano size silicon particles were homogeneously embedded in graphene nanosheets resulting in the formation of plenty of nanosized free spaces. This porosity demonstrated improvement in the electronic conductivity, capability, and cycling stability with 976 mA h g\({}^{-1}\) at current density of 50 mA g\({}^{-1}\) by 20 h P-milled composite.