Voyager 1 uses nuclear batteries that have been qorking since 1977, but will probably exhaust by 2036. Then this probe will be totally useless, disconnected and dead metal.
It will go on traveling. It is very unlikely that it will hit something. It will take tens of thousands of years before it reaches another star system. Now it takes 47 hours to send a command to it and get the feedback or response. If it will fall into the hands of an intelligent alien race after one hundred thousand years, by that time it might be possible human will no longer exist. So sad.