The fun part is that the inhabitants of Zion are, canonically, shown to have very incomplete information about the actual state of the world, their own history.

Neo is told basically ‘we think it is the year 2XXX, but really, we have no idea’, in the first movie.

Without spoiling much… Morpheus is wrong about some things, some pretty important things.

Hell, so is the Architect and even the Oracle says that some things are beyond her ability to predict.

But anyway… its entirely possible that the battery explanation is just another thing that Morpheus, the broad understanding of Zion itself, is wrong about.

So this doesn’t actually ‘break’ the canon at all.

In fact, I’d argue that it makes the idea of ‘free your mind’ even more interesting and complex.

Even the truthseekers and truthtellers… can be wrong.