Silicon Nanoparticle/Nanowire and Graphite Composite Anode with Increased Binder for Lithium-Ion Coin Cells Aimed at High Energy Density Battery Applications

Silicon and graphite composite anode materials were prepared for a lithium ion half-cell with lithium metal as the reference electrode. All silicon/graphite composite anodes were prepared in the lab with mixing of slurry using ball milling technique. Battery grade copper foil was used as the current collector for the anode. The anode was coated using the doctor blade technique with thickness of 100μm and further calendared to provide higher energy densities for active material per cubic volume. The ratio of binder used was significantly higher than previously tested to show silicon material takes longer to detach from current collector with increased cycle life.;Galvanostatic cycling show lithiation and de-lithiation of silicon anode with respect to lithium metal. Impedance measurements were taken for coin cells prior to cycle life tests. Silicon anode half-cell was charged/discharged for many cycles showing improved cycle life with great capacity retention. Charts show silicon expansion of material after cycle life however due to increased amount of binder material less silicon separates from the copper current collector initially. The coin cells made provide reproducible results which can be used for practical applications and have the ability for large volume production of high energy Li-ion batteries.