changing the battery shouldn't cause any idle surging like that. If you were to use your finger and close off the base idle port, the idle valve should still be able to "open up" and compensate for that without much problem, as long as all else is ok.
To me it looks like a large enough air/vacuum leak to the point where the idle valve can't compensate "close" enough to bring idle within spec. ecm puts the idle valve in this surge mode.
Last time i seen something like this, the pcv valve was clogged, its hose collapsed and had split open.
If your check engine light is on, that could point to a whole other direction too.
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