......Back in the day it was very common to wire up all your "accessories" to either a quad AA battery pack or a 9V. Back then the max voltage was 7.2v so I am sure we were maxing out the lights but they never blew or cooked anything. Todays R/C vehicles mostly run on 8.4v-11.1v. so I do not see why you would not be able to direct wire it to a 9v. and be OK !!!