Part of Lithium plating and Cell degradation. One of the Reasons for atypical cell degradation.


This is due to Arrhenius law: at lower temperature, Lithium ions are less likely to have high enough energy to cross the potential barrier (their energy is described by Maxwell—Boltzmann distribution), both on the anode-electrolyte interface (SEI), and within the graphite structure. The effect is that Lithium ions "crowd" close to the SEI, on both the anode and the electrolyte sides. On the anode side, this leads to further increase of Cell diffusion voltage. On the electrolyte side, this "Lithium crowding" is the direct precursor for Lithium plating.

As an example, in a commercial cell Lithium deposition (plating) starts at a charging C-rate ≥2C for 50 °C, and already at ≥0.5C at 12 °C. [1]

Lithium plating starts at about 25 °C when charging at 1C rate: see Lithium deposition overtakes the SEI growth as the leading capacity fade mechanism at 1C rate and 25 °C.

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More Lithium plating happens closer to the surface of a cell when charged at very low ambient temperature because the outer parts of the cell will be cooler:

Petzl et al. cycled 26650-type cylindrical cells at −22 °C with a charging rate of 1C and found a grey homogeneous film on the anode. They reported that the mass per area of the anode was higher on the outer part of the jelly roll, suggesting more Lithium plating near the cell housing.

References

[1] In-situ detection of lithium plating using high precision Coulometry (2015)