To change your iPhone 5G settings for better battery life, follow these steps based on the information provided:

  1. Open the Settings app on your iPhone.
  2. Go to "Cellular" (or "Mobile Data" depending on your region and carrier) and then tap on "Cellular Data Options" or "Mobile Data Options" if you're using Dual SIM, choose the number you want to change.
  3. Find the "Voice & Data" section.
  4. Set "5G Auto" to take advantage of Smart Data Mode, which will switch between 5G and LTE to conserve power when 5G speeds don't provide a noticeable advantage.

However, if you want to completely disable 5G to prioritize battery life, choose "LTE" instead of "5G Auto". This setting might reduce your iPhone's battery life, but you'll experience slower data speeds consistent with LTE networks.

Additionally, to further optimize battery life:

  1. Enable "Low Power Mode" under "Battery" settings or through Control Center to reduce power consumption (5G is disabled in this mode except for video streaming and large downloads on iPhone 12 and iPhone 13 models).
  2. When Low Power Mode is on, the 5G standalone feature (where available) is disabled on iPhone 12 models, so keep this in mind if you specifically need the benefits of 5G standalone.

Remember that these settings are subject to change based on your carrier and network conditions, and by changing these options, you may notice slower data speeds and some features taking longer to update or complete.