It's probably a coincidence.
It happens loads. You change one thing, and something else happens, and you assume they are related. Our 145QV battery went flat, and then it wouldn't start. Turns out the relays had corroded, so they were going to conk out at anytime. They chose to do it when I was tinkering with the battery.....
Only other thing is if the airbag ECU has got spiked when you were changing or charging the battery.
Whatever the reason, the light is on, and you can't fix it at home as far as I know.