Given what we can do with stealth technology today, imagine the problem of even discovering the presence (let alone position, velocity and acceleration) of something that doesn't want to be found.
The only two "giveaways" would be the heat signature from its power source (not just propulsion, but life-support) and whatever it accidentally occults as it moves across the background of stars. The heat can be drastically reduced by towing the power source a long way behind the main craft and having it very, very dispersed so the Watts per square metre of I.R. are very small. The occultation problem can be reduced by choosing a path that stays away from the galactic plane.
So most battles would be ones of sneak attacks and defensive fire. It might be possible to devise some sort of A.I. mines, or even simply fire a cloud of sand in the general direction (assuming the relative velocites of target + sand are high enough, that could be all that's needed).
However, I have a feeling that most "wars" in the future, whether in space on on Earth, will be economic in nature and "fought" over decades rather than wham-bam shooting battles.