The Lambourn trainer felt four quick runs were the reason behind his disappointing performance in the Nunthorpe Stakes.
Battaash had gone to the Group One at York last month on the back of three impressive victories, but his winning streak came to a sudden halt on the Knavesmire when he was only fourth to Marsha.
"We've been pleased with him since York," Hills told At The Races.
"We've had a chance to freshen him up. He'd had four quick races and it probably just got to him mentally, the occasion at York.
"He did a swinging canter on Wednesday and we were delighted with that.
"It's all systems go for the Abbaye on Sunday week.
"The great thing there is we will be able to saddle him in the stable, so it will be a much easier lead-up at Chantilly than at York."