12V surprise

"Possible" if you left it connected for 5 minutes before trying to Ready it.



A better plan is a lithium jump box in the cabin accessible without opening the hatch and practice hooking it up under the hood.

Often Good Samaritans and tow truck drivers don't know how without direct access to the 12v battery.

 

$227 for an OEM battery at the dealer is not bad at all. Actually, it is awesome. Prius uses AGM battery. They are expensive. I paid $200+ for one I got from AutoZone for my 2010 Gen3 Prius. It was a diehard battery, their brand name.
So, you paid the same and they did the job. Excellent in my opinion.