Li-iоn bаtteries аre well knоwn. The reаctiоn of a Li-ion battery is shown below LiCoO2 + C6 ↔ Li1-xCoO2 + LixC6 Forward reaction occurs during the charging process, and the reverse reaction (discharge) occurs when the battery is in use. What is the oxidation state of Co in the LiCoO2 species? (Hint: Li has the same oxidation number as other elements in the same group)