Battery problem with latest iOS update on my 5th Gen iPad

Symptoms appear to be those of an exhausted battery, but we, just users like you, cannot diagnose that kind of issue remotely, sorry.

I suggest that you contact Apple Support directly (they have tools to run remote diagnostics, battery included) using this link:--> Get Support, or make an appointment (*) and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> Apple – Location Selector. After checking it out, they'll give you all the available options.

Regards

Giulio

(*) You can do it:

• Online:--> Genius Bar Reservation and Apple Support Options - Apple;
• Contacting a local Apple Store or AASP among the list provided above;
• Using the "Apple Store" app, available and downloadable from AppStore.

If you are experiencing abnormally high battery utilisation after a system software update, you should first perform a forced-restart of your iPad - as doing so will often clear isolated software or post-update issues:

• On an iPad with a Home button: Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.
• On other iPad models: Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the top button. When the Apple logo appears, release the button.