Are there any particles with charge higher than one $1e$? I know there are particles with $1e$ charge like protons and electrons. Atomic nuclei can have charge of $Ze$ on basis of their proton number $Z$. Are there any particles out there with charge $2e$ or $3e$....etc?
 A: Under the current understanding of the Standard Model, there are only three possible charge magnitudes for fundamental particles: $e$ (for leptons such as electrons), $\frac23 e$, and $\frac13 e$ (for various types of quarks). There are also uncharged fundamental particles (neutrinos).  So if we restrict ourselves to fundamental particles, the answer is that no more highly charged particles exist.
However, baryons are composite particles formed from three quarks, and if all three have charge $\frac23 e$, then the resulting particle will have net charge $2e$.  This would be the highest charge possible for a conventional baryon;  and several such baryons have been observed (such as the $\Delta ^{++}$ noted in JEB’s answer.)
Exotic baryons such as pentaquarks could, I think, in principle even have a charge of $3e$ (for example, a pentaquark with valence quarks $uuuu\bar{d}$.) But only a couple of pentaquark baryons have been detected to date, and both of them have a charge of magnitude $e$ only.
A: No, at least in the standard model the highest charge of any elementary particle is $\pm e$. You can of course find composite particles with higher net charge.
A: The $\Delta^{++}$ baryon, which is a member of the isospin $\frac 3 2 $ delta-quadruplet.
