  We consider a dark sector scenario with two dark matter species with opposite
dark $U(1)$ charges and an asymmetric population comprising some fraction of
the dark matter abundance. A new mechanism for boosting dark matter is
introduced, arising from the large mass hierarchy between the two particles. In
the galaxy, the two species thermalize efficiently through dark Rutherford
scattering greatly boosting the lighter dark matter particle, far above the
virial and escape velocities in the galaxy, while the dark charge prevents it
from escaping. We study the consequences of this scenario for direct-detection
experiments, assuming a kinetic mixing between the dark photon and the photon.
If the charged dark sector makes up 5% of the total DM mass in our galaxy and
the mass ratio is between $10^3-10^4$, we find that current and future
experiments may probe the boosted light dark matter for masses down to 100 keV,
in a hitherto unexplored parameter range.
