  The sequential group-by-group charging/discharging in Li batteries with
phase-separation thermodynamics was detected by numerical simulations and
justified by several experiments published in literature. The present work is
the first to quantitatively predict the main characteristics of the sequential
symmetry breaking (SB) such as the average Li concentration and the fraction of
the low Li part at the SB points. Using a reduced two-zone (low and high
concentration) model we derived an approximate solution predicting the effect
of initial separation or of imposed parameter perturbation referred to as
'noise' on the SB characteristics. We suggest that the governing parameters
that account for the complex effect are the liquid potential drop over the
cathode and the noise factor. A bifurcation map showing the lowest current
boundary that ensures a homogeneous lithiation/ delithiation as the function of
noise is constructed
