iPhone Battery Usage history shows 0% for previous days

From Gemini AI:

Your iPhone's previous battery usage statistics clear automatically during an iOS update because the system cache and usage history reset when the new software is installed.

Why It Happens

• System Reset: Installing a major update restarts the operating system's internal tracking metrics.
• Fresh Data: The phone starts logging fresh battery consumption data from the exact moment the update finishes.
• Normal Behavior: This wipe is an expected part of the software installation and does not affect your actual battery health or device performance.

faijulrafe wrote:

I don’t think this explanation fits my situation. I updated my iPhone on August 18, 2026, but the Battery Usage history did not disappear immediately after the update. I continued using the phone normally, and the issue only appeared around August 31–September 6 — roughly two weeks after the update.

Also, the affected dates are still selectable in Battery Usage, but they show 0% battery usage, 0 minutes Screen On, and 0 minutes Screen Off, even though I actively used the phone heavily on those days.

Interestingly, September 7 is recording normally again (56% battery usage, 5h 21m Screen On, 22m Screen Off).

Is there any Apple documentation confirming that an iOS update is expected to erase Battery Usage history, especially with a delay of around two weeks? If not, could this instead be a Battery Usage analytics/reporting bug?

In answer to your first post question, no we cannot check the usage analytics database for your phone at all. This is a user to user only forum and no one here posting or reading, works for Apple or has access to any Apple systems. Apple isn't tracking the usage statistics on your personal phone anyway. That is handled on the device directly.

Your tag line suggests you have an iPhone 13 Mini. It's more probably that if you have the original battery in your phone, it is failing by now. Batteries don't last forever and eventually, when their health dips to 80% or lower, it's time to pay Apple to replace the battery. To check your iPhone's Battery Health, open Setting > Battery > Battery Health - is it 80% or lower? If yes, it's time to replace it. Apple Service and Repair for iPhone Battery - Apple Support

faijulrafe wrote:

But my iPhone 13 mini currently has 93% Maximum Capacity with only 203 charging cycles, so the battery is nowhere near the 80% threshold you mentioned. My issue is specifically with the Battery Usage history: several previous days show 0% battery usage, 0m Screen On, and 0m Screen Off, despite the fact that I used the phone heavily on those days, while the current day’s usage is being recorded normally.

So why are those previous days showing 0% / 0m if the phone was actively used?

OK. So what exact model iPhone do you own? Your tag line says iPhone 13 Mini. iPhone 13 Mini is not capable of showing the cycle count for battery health. The very first iPhone which showed cycle count was iPhone 15.

I can't possibly know why previous days showed 0% active usage on your iPhone. No one here could possibly know. Again, this is a user to user only forum. You can certainly schedule an appointment at your Apple Store Genius Bar and have your phone tested --> Genius Bar Reservation and Apple Support Options - Apple

faijulrafe wrote:

Yeah, you’re right 13 mini doesn’t natively show the cycle count in Settings. I’m getting those numbers through a Shortcut that reads the battery analytics data, which gives me:

*Original Battery Capacity

*Current Battery Capacity

*Number of Complete Charge Cycles

*Relative to when it was new, current battery capacity is…

So that’s where the 203 cycle count and 93% capacity figures came from.

And thank you for taking the time to respond and explain this. I really appreciate your time and help.

Shortcut? You mean like an app such as 3uTools, which is not very accurate and can't be counted on. iPhone 13 Mini was released in 2021 and discontinued in 2022. Best case is your iPhone is 4 to 5 years old. It would be miraculous for an iPhone from 4+ years ago to have a battery health of 93 with only 203 cycles. Did you buy the phone brand new from Apple or used from someone?