Lithium Plating

What is it?

Lithium plating is a phenomenon that can occur in lithium-ion batteries when the battery is charged too quickly or at low temperatures. When this happens, some of the lithium ions in the electrolyte solution may be deposited onto the surface of the battery's anode (negative electrode) instead of being incorporated/intercalated into the anode material.

    In simpler words, lithium ions are not able to move inside the anode particles and are jammed over the anode electrode while charging, either due to faster charging or due to lower temperatures.

How potential of anode and lithium metal change during this process?

During normal operation of a lithium-ion battery, the potential of the anode is kept at a lower voltage than that of lithium metal, typically around 0.01-0.1 volts. This allows the lithium ions to be absorbed by the anode material during charging and prevents the formation of metallic lithium on the anode surface. In case of plating as the amount of lithium metal on the anode surface increases, the potential of the anode with respect to lithium metal may become more zero or negative and the lithium ions will no longer be absorbed by the anode material.

Effects 

Lithium plating can have negative consequences for battery performance and safety. The plating layer can reduce the capacity and efficiency of the battery, leading to decreased performance and shorter overall lifespan. Additionally, if the lithium plating layer becomes too thick, it can cause a short circuit within the battery by penetrating through separator and connecting to cathode layer which can result in overheating or even fire.

 

How to prevent? 

To prevent lithium plating, it is important to charge lithium-ion batteries within their recommended temperature and current ranges. Charging at low temperatures or at high currents can increase the risk of lithium plating. It is also important to use chargers that are specifically designed for the type of battery being charged and to follow the manufacturer's instructions for charging and storing the battery.