Thanks up to this point I've used the gas engine almost exclusively. But want to use the electric only option if I can feel comfortable with it. Have you seen your miles available increase the more you charge yours?

Peace and health
Bob

Is my understanding wrong on Prius'? Even the plug in one. It still charges the battery when you're driving. Mainly in slowing down and stopping. Am I not correct?
8 miles for charge means nothing to a Prius. That's just how far it will go with only battery power, and that's all.

Yea the regular Prius uses the engine and regen to charge the battery back like most other hybrids, which you can they use to drive solely on electric power. The plug in works exactly the same, but with the ability to charge it yourself, so you can always start with a full battery, or charge when out and about.

It's clearly not keeping a full charge. I need to get it into the dealer and determine what the issue is and hope it's covered under warranty

This car is 5 years old. The batteries aren't charging fully. .... You're hoping it's a warranty? ... When battery cars came out. They expected a person would have to replace the batteries in 5 years.

You're driving this in full engine mode. Not using the batteries at all. The car is designed to use the batteries part time. It decides when. The batteries are to assist. You just have to choose the right mode for the car. That's all.
I don't think anybody drives their Prius in full battery/electric mode. Unless they run out of gas.

Yes, it would be nice to have the batteries charging fully after 5 years. But there is definitely something lacking in your thinking here.
Even Toyota, who is famous for covering defects out of warranty. I doubt seriously they would cover this under warranty. It's like covering worn tires under warranty.

Found this:
To answer the first one, John Hanson, Toyota's National Manager, Environmental, Safety & Quality Communications, responds:

"The battery pack in any hybrid Toyota is warranted either for 10 years or 150,000 miles (in states with California emissions laws) or 8 years or 100,000 miles in all other states."

And, he adds, "There's no pro-rating at all. The battery will be replaced at no cost if necessary during the warranty period."

As for the effect on used Prius prices, there doesn't appear to be a discount for older Priuses based on concerns about the life of the rechargeable battery pack.

Indeed, Toyota says the battery pack is one of the least-frequently replaced items across all Prius models. And some proportion of the packs it has to replace haven't failed, but were damaged in collisions or other accidents.

And how many miles does this Prius have?

Post #7. 81000.

Forgive me for not comprehending the entire thread before posting.
I seriously do believe in Toyota. I can't believe some of the stuff they have done.
I'm confident the OP doesn't have anything to worry about. Just take it in. Toyota will take care of him.
I still say. Even now. There is no reason to run in gas mode only. None at all. I hope I didn't misunderstand his statement regarding that.

I have contacted toyota and they have assigned me a claim number. I have to take the prius to the dealer and have them do a diagnostic then toyota will act according to the findings. Toyota says it will be up to the dealer weather the cost of the diagnostic will be paid for by me or toyota. May take some time to get an appointment. I'll let you know the outcome.