In the production of rechargeable lithium-ion batteries, cathode efficiency is highly dependent on the mass proportion of active lithium within the cathode material, lithium cobalt oxide (${LiCoO}_2$).

Calculate the percentage (%) by mass of lithium in lithium cobalt oxide (${LiCoO}_2$). Give your answer to 3 significant figures.

Relative atomic mass ($A_r$): $Li=6.9$. Relative formula mass ($M_r$): ${LiCoO}_2=97.8$.