  Acceleration of polarized electron~(positron) beams in a booster synchrotron
may suffer from depolarization due to crossings of many spin depolarization
resonances, which could limit its applications. We have studied the spin
depolarization resonance structure of a 100~km scale booster lattice of the
Circular Electron Positron Collider~(CEPC). The lattice has 8 arc regions with
hundreds of FODO cells, interleaved with straight sections, which leads to a
high periodicity. Our analysis shows the contributions to the strength of
intrinsic and imperfection spin resonances add up coherently near the super
strong resonances beyond 120 GeV, but mostly cancel out and result in generally
weak resonance strengths at lower beam energies. Detailed simulations confirm
that beam polarization can be mostly maintained in the fast acceleration to
45.6 GeV and 80 GeV, but severe depolarization may occur at even higher
energies. This study suggests the possibility of acceleration of polarized
electron~(positron) beams to ultra-high beam energies without the help of
Siberian snakes, and supports injecting highly polarized beams into the
collider rings as an attractive solution for resonant depolarization
measurements and longitudinal polarized colliding beam experiments for future
100~km scale circular e$^{+}$e$^{-}$ colliders.
