langue fr SAFT - 08/05/2021

What is passivation in a primary lithium battery? motion design part 3

Passivation is the main observable effect of a surface reaction that occurs spontaneously onto lithium metal surfaces in all primary Lithium batteries based on a liquid cathode. The corrosion of lithium metal by liquid Thionyl Chloride into lithium ions leads to the formation of a solid protecting layer, the passivation layer. This layer helps in preventing further corrosion and more importantly, avoiding any internal short-circuits of the battery. It acts in a similar way to paint protecting against metal corrosion; it protects the cells from discharging on their own and enables their long shelf life.
In the third video of our series, we explain the particularities of passivation and we talk about the factors that are known to have an impact on the passivation effect.
And if youd like to go further, read our article The 7 most common pitfalls about passivation (and how to avoid them)

This video is part of a series of 4 videos that explain the basic functioning of a primary lithium battery, and the main chemical reactions that occur in a Lithium Thionyl Chloride battery.
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