Battery? You're talking about a laptop, aren't you?
I've encountered several types of issues caused by a failing laptop battery, one of the strangest being the total loss of anything networking related including NIC's.
Take the battery out and use mains only for some time to see if that normalizes the situation.
Or are you talking about the bios battery, the small button cell? If it is failing, some modern systems won't boot at all. If in doubt, replace it and reset your bios to "optimized settings" or to your personal ones.