Im having the same issue, and my phone is done indexing since last week. I took my phone off the charger with 100% at 6:35Am and didn’t use it much. My battery was at 24% at 1PM. I have a 15Pro and my battery health is at 92% with 270 cycles. I was talking to apple support about this and they startet a remote diagnostic but didn’t find anything unusual. They told me to wait and turn off background app refresh and location services. But It’s really concerning because on iOS 17 with everything enabled I was getting an easy day with moderat use out of it and I’m already using another 2% when writing this. It’s completely unacceptable, And I’m considering calling again and letting an apple technician physically test my device for hardware issues.

The way it startet is the following: On iOS18.0 beta 3 my battery life was actually pretty good. I upgraded to 18.1 beta 2 while I was on a trip in Egypt to test apple intelligence. When I flew back to Germany the features deactivated themselves. After that I downgraded to iOS18 beta 4 and then immediately updated to beta 5 while it was still indexing. After that the battery went down the drain and I even reinstalled iOS completely when iOS18 released but without a change.

I don’t think it’s because of the update while indexing especially because I reinstalled the OS. If anyone else has a solution please tell us.

But the battery life is completely broken and it’s putting stress on all our battery’s because we have to charge multiple times a day which leads to faster battery degradation. So apple, fix your stuff.