iPhone 11 gets hot and battery charge rubbish after latest iOS update

Hello Kittycat701,

Welcome to Apple Support Communities. We understand your iPhone is experiencing a shorter battery life and there's a concern about the operating temperature of the battery.

Having peace of mind that your iPhone is delivering optimal battery performance is vital. We'll be happy to help.

With the battery operating at a higher temperature, did you notice a temperature warning screen appear on the display of your iPhone? Here's an article with more information and how certain situations may cause the battery to operate at a higher temperature: Keeping iPhone, iPad, and iPod touch within acceptable operating temperatures

For the concern of the battery, our recommendation is to review the battery health on your iPhone. Reviewing the condition of the battery health, can help determine if the battery needs to be serviced. For details and the proper steps to take, please follow the section in this article that says, "Battery Health": iPhone Battery and Performance. Check also Settings > Battery for the last 24 hours and see if a specific app(s) account for the lower then expected battery life.

If there's no issue with the battery health, the next step is to maximize the battery performance by adjusting the settings on your iPhone. Here's a helpful article with the proper steps: Maximizing Battery Life and Lifespan. If you make any changes to your device, please charge the phone to 100% and then test for 48 hours to see how things go.

In addition, you'll want to ensure that your iPhone is on iOS 14.0.1: Update your iPhone, iPad, or iPod touch. Please charge the iPhone to 100% after updating and then test for 48 hours to see how things perform.

Kind regards.