Why do we do electrolysis and electroplating using warm electrolyte?
ringo makes good points in his answer. Additionally, though, the increased temperature enhances mass transfer of ions to/from the electrode surfaces by at least two mechanisms:


Higher temperature results in lower electrolyte viscosity, leading to a thinner fluid dynamic boundary layer and concomitant greater mass transfer to/from the electrode surfaces.
Higher temperature also increases the diffusivities of the electrolyte solutes, which also contributes to increased mass transfer to/from the electrodes.