Actually it was in Escape - Cornelius relates the history of the Ape civilization and in his telling it is an Ape named Aldo who leads the rebellion. It was in the CIA interrogation (my bad when I said committee - it has been a bit since I watched Escape) and at approximately the 52 minute mark is where Caesar names Aldo as the ape that first said "No" and so forth.
In Battle Caesar views videos telling him how Earth was destroyed (per the video at about 28 minutes in by the Gorillas) and decides to chasing history.
Cornelius is talking about Aldo of the future from the Col Taylor timeline. The Aldo in Battle is a different Aldo (perhaps the first?) They are different apes in different timelines, even though the actor who played him is the same. Many of the actors went though the movies into the future, along with "Stevie" (the female doctor) and several of the minor characters, as different people. Stevie became one of the masked mutant humans in Beneath the Planet of the Apes, but was a different character in that timeline (she committed suicide with poison).
The scene you are referring to was when the professor was interviewing Zira and Cornelius about how the apes came to power. Cornelius says: "At first, they (the apes) merely grunted their refusals. But then came Aldo. He did not grunt. He said a word spoken to apes time and time again. He said 'NO'".
This conflicts with its own canon, since it was actually Lisa we see in Conquest who utters the word "No". None of the other apes in the Conquest timeline can speak except Caesar (and finally Lisa). Caesar is the one who started the uprising, not Aldo. The first Aldo we see in the earlier timeline is Aldo of Battle who is the first ape to kill ape. I am now watching Battle again, just to be sure. . Whatever the case, Caesar is not reacting to or trying to manipulate future events. Only this guy was: