He did stock clones in Mount Myoboku when he was fighting Pein, but he does not need it to be able to enter Sage Mode, he only has those clones, so that he can prolong his Sage Mode.
He can keep his clones anywhere to gain nature chakra but his clones should be not disturbed during this process which dosen't seem possible around battleground...
He never needs clones to use Sage Mode. The extra 2 clones in the Pein arc was just so Naruto could continuously use Sage Mode because he knew his fight would be long.