Low Power Mode Slows Down iPhone 15 Pro Max

Low Power mode is designed to slow down the iPhone. The priority shifts from higher performance to saving battery power. In order to save battery, screen is dimmed and slowed down, and high efficiency processors are used rather than high performance. This is normal and expected behavior.

That's what low power mode does; there's nothing to fix.

When Low Power Mode is on, your iPhone or iPad will last longer before you need to charge it, but some features might take longer to update or complete. Also, some tasks might not work until you turn off Low Power Mode, or until you charge your iPhone or iPad to 80% or higher.

Low Power Mode reduces or affects these features:

• • 5G (except for video streaming) on iPhone 12 and iPhone 13 models
  • Auto-Lock (defaults to 30 seconds)
  • Display brightness
  • Display refresh rate (limited up to 60 Hz) on iPhone and iPad models with ProMotion display
  • Some visual effects
  • iCloud Photos (temporarily paused)
  • Automatic downloads
  • Email fetch
  • Background app refresh

Use Low Power Mode to save battery life on your iPhone or iPad - Apple Support

Hi,

This happens because when the Low Power Mode is turned on, iPhone's screen will be limited to 60HZ, and the processor will also be limited to reduce the battery usage.

You can take the link below as reference of how Low Power Mode affect your iPhone usage.

Use Low Power Mode to save battery life on your iPhone or iPad - Apple Support

No it’s like really bad. I’ve never had an iPhone that lags like this when it is on low power mode. It is ridiculous how laggy and delayed it gets as soon as you turn it on. Low power mode has never done that to any of my previous iPhones.

Hi ! i have the same problem on iPhone 15 promax,

I did not have this problem with my normal iPhone 13, in a low power mode it was working exactly like when not in low power mode.

Have you found a solution?

I will contact Apple support

It depends upon what you're doing; I see negligible differences between Low Power mode and normal mode.