Battery replacement time?

[Coast Woman]

I have a ridiculously low mileage 2013 CMax Energi (34,000 miles). Really. I am the original owner, purchased the car new in December 2013. Love it. I live in an excellent climate for this car, never freezes here, temps over 75° for just a few days a year. The battery is now just charging to 8 miles. Is it time to replace the batteries? I am 77 years old, would like this to keep this as my toes-up car and not buy a new one. 

[homestead]

8 miles seems a little low for 34k miles on the car.  Maybe there is a problem with the battery pack.  I would get it diagnosed before getting it replaced.

Or just drive it as is, a new battery would not add a lot of value.

[cr08]

I'd first start by getting the actual capacity of the battery currently. The estimated range is practically useless as a health indicator as a lot of factors can impact the numbers. Here's the test you need to do:

 

1) Fully charge the car

2) Drive it in EV mode ONLY (avoid things that can cause the ICE to start, ie: No highway driving, no cabin heat, as few active accessories as possible)

3) Drive until the plug-in charge is depleted.

4) Once the plug-in charge is used and it falls back to hybrid operation, safely stop somewhere and shut off the car. The trip summary on the left screen will list the kwh used. This is the number you need. 5.5kwh is the brand new plug-in capacity from the factory. Anything above 4.0 is still in good territory.

[stolenmoment]

Remember, the guess-o-meter is based on your recent driving.  If you have a lead foot, it might think that you only have eight miles of juice.  Follow cr08's instructions, that will get to what you really have available.