[Dgray2712]

Unlocked my phone, and it said the battery was 10%. Plugged it in. After 5 minutes, it was showing 48%, but the icon is yellow. Why would that be? Is it just because of how cold it is? It was sitting in my truck for about 20 minutes, and it’s -6.

[Rob Phillips]

Nothing is wrong. You’re just in low power mode.
https://support.apple.com/en-us/HT205234

[tadpoles]

I did a Google search and it indicated this is because you have low power mode enabled. You can disable it in settings—>battery.

[Dgray2712]

Thanks. Have no idea how that happened.

[Tartarus]

Thanks. Have no idea how that happened.

When you get a notification that your battery is running below 20%, you can choose to either dismiss that notification or go in Low Power Mode.
It seems to me that you inadvertently chose for the latter.
Nothing to worry about.
You can disable that in Settings > Battery, or wait for the battery to be charged to at least 80% percent.

[Annie_8plus]

When you get a notification that your battery is running below 20%, you can choose to either dismiss that notification or go in Low Power Mode.
It seems to me that you inadvertently chose for the latter.
Nothing to worry about.
You can disable that in Settings > Battery, or wait for the battery to be charged to at least 80% percent.

Exactly this! I’ve done this before unknowingly!

[bamf-hacker]

My kids turn it on intentionally to save battery power

[Annie_8plus]

I used to do that as well before I got my 8 Plus. With it's good battery life, I don't have to worry about is so much!