It would help if your question was a bit clearer or more specific.

There was no battle on the scale of say, Leyte Gulf or the Philippine Sea in the middle of the Atlantic during WW2 but there were plenty of large scale engagements between German submarines and allied convoys. The largest convoy battle of the war (John Keegan's The Price of Admiralty has a chapter on this battle) was over convoys SC122 and HX229 in March 1943. About a hundred merchant ships, a dozen allied escorts and 40 U-boots were involved and more than 20 ships were sunk. I think that counts as an important battle.

Another example of an important battle is the hunt for the Bismarck (the strategic significance of which has been vastly overhyped in popular culture IMO). Again, it wasn't on the scale of some of the engagements fought in the Pacific but more than half a dozen RN capital ships were involved. There was also the Battle of the North Cape (if you count the Norwegian Sea as part of the Atlantic) which resulted in the sinking of the Scharnhorst. I could go on and on, but hopefully these examples are enough to answer your question.