The lithium metal, due to its highly reactive nature, directly undergoes chemical reaction with the solution of the electrolyte as soon as it is deposited on the cathode leading to the formation of a solid electrolyte interface (SEI) instead of forming lithium clusters. During the charging of the battery, the negative terminal of the cell has excessive electrons from the power supply. These electrons travel to the cathode material as lithium ions via a liquid electrolyte. Lithium is intercalated into the transition metal oxides present in the cathode as LiMn2O4 or LiCoO2.

Here are some reasons why lithium is not deposited at the cathode:

Electrolyte decomposition: Lithium metal is highly reactive and can easily react with the electrolyte, leading to the formation of a solid electrolyte interface (SEI) layer on the surface of the cathode. This SEI layer prevents further deposition of lithium metal.

High overpotential: The electrochemical potential required for lithium deposition is higher than the potential for other reactions, such as hydrogen evolution or oxygen evolution. This means that lithium metal is not deposited until these other reactions have occurred.

Low solubility: Lithium metal has a low solubility in organic solvents, which are typically used as electrolytes in lithium-ion batteries. This means that lithium metal tends to precipitate out of the electrolyte and form solid clusters, rather than being deposited at the cathode.