13ProMax turns off with 70% battery, boot loops until plugged in and shows 1% battery

[Jadedogsome]

I have a pretty new iPhone 13 Pro Max with battery health of 100%. Randomly while using it it shut off and would not turn on regardless of inputs including force restart. After plugging in it would the boot loop for a few minutes eventually turning on and showing 1% battery. I looked later at the battery Charge state for the past 10 hours which shows a ~70% charge dropping suddenly to around 1%. Anyone know why this could be the case/has experienced something like this?

 

[eicca]

That sounds like a bad battery cell.

The bad news is Apple’s “battery health” feature really isn’t that smart, yet they trust it completely. I had a 6S with a very obviously faulty battery within the warranty period but Apple refused to do anything about it cuz “health” said 94%. Only when I made them open the phone to see it was swelling up did they actually do anything.

 

[Jadedogsome]

That sounds like a bad battery cell.

The bad news is Apple’s “battery health” feature really isn’t that smart, yet they trust it completely. I had a 6S with a very obviously faulty battery within the warranty period but Apple refused to do anything about it cuz “health” said 94%. Only when I made them open the phone to see it was swelling up did they actually do anything.

Ironically this happened after one year of use. This phone was covered by Applecare and replaced for free. This was about a month ago so I doubt it would be this rapid... Thankfully it seems that this was a one-off event, still strange.

 

[eicca]

Ironically this happened after one year of use. This phone was covered by Applecare and replaced for free. This was about a month ago so I doubt it would be this rapid... Thankfully it seems that this was a one-off event, still strange.

Cell failure on a young battery is still entirely possible.