There is no time speed up at the tactical level.
If you put your ship into flee-mode (red arrow) it will leave the battle area if it gets about kilometer away from the closest enemy. If all your ships are in flee mode and AI does not shoot you for 30 secs (it is too far behind or does not have angle) the AI will give up the chase.
If all AI ships are fleeing, you will be prompted whether you want to continue chase or let them go. If you continue chase, you can stop the battle at any time if you feel reaching them is taking for ages.
All this is to say that naval battles should not take too long. Upcoming patch will also result mast down AI ships in flee mode to surrender more easily so that you don't have to hunt down almost killed vessels so much.