If the number of collisions of the free electrons with the lattice is decreased, then the drift velocity of the electrons increases. Current i is directly proportional to the drift velocity ′Vd′​ and is given by the following relation:i=neAVd​, where ′n′  is the number density of electrons and ′A′ is the area of the cross-section of the conductor. So, we can easily see that current increases with an increase in drift velocity.