Convention Lithium / Ion batteries contain approx 20 % graphite but more efficient next generation batteries will be primarily Lithium/metal anodes ( requiring a solid state seperator ) 

This is the direction of the EV companies according to an industry insider - most graphite will be used for writing materilas , primarily lead pencils 

“Lead” pencil cores are made of a mixture of clay and graphite. Loosely cleaved graphite flakes mark the paper, and the clay acts as a binding material. The higher the graphite content of the core, the softer the pencil and the darker its trace. There is no lead in what are known as lead pencils. The name originated in Europe when graphite was called “plumbago” or “black lead” because of its metallic appearance. Graphite’s use as a marker dates from the 16th century in northern England, where local legend states that shepherds used a newly discovered graphite deposit to mark sheep.