The Addicks, promoted as League One champions last term, have endured a tough start to life in the higher division.
But they followed up last week's thrilling 5-4 victory over then-leaders Cardiff with a 2-0 success at lowly Bristol City on Sunday.
Powell is confident his players can build on their six-point haul as they continue to get used to being back in the second tier.
"I think now we can look forward to knowing we can perform away from home and get three points and get clean sheets," he said.
"That sets us up now for the second third of the season. It's been tough for us, it's been up and down, admittedly, but I think the players will really get a lot of heart from beating Cardiff and Bristol City."