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.

[knahs42]

My 2014 Ford Cmax SEL (hybrid not electric) with 78,000 miles now needs to be jumped every time I go to use it.  Upon reading, I assume the 12 volt battery probably needs replaced.  Would an AGM battery be a better choice?  How long does the hybrid battery usually last?  From what I've read it seems to be 10-12 years so I am figuring that is also may be an issue?  I recently moved to a new home and the garage is not as warm as at the other house.  I investigated getting a heater but was told it would cost a lot of money to keep garage heated at 40 degrees.  I asked Ford about an engine block heater but they said it should not be necessary.  Ford is going to charge $169 to "diagnose" issues.  This is dealer I bought vehicle new at in 2014.  Is this reasonable?  Obviously I could purchase a better quality battery if I had the $169 to apply to battery.  Any suggestions?

[nogoodbum]

3 hours ago, knahs42 said:

My 2014 Ford Cmax SEL (hybrid not electric) with 78,000 miles now needs to be jumped every time I go to use it.  Upon reading, I assume the 12 volt battery probably needs replaced.  Would an AGM battery be a better choice?  How long does the hybrid battery usually last?  From what I've read it seems to be 10-12 years so I am figuring that is also may be an issue?  I recently moved to a new home and the garage is not as warm as at the other house.  I investigated getting a heater but was told it would cost a lot of money to keep garage heated at 40 degrees.  I asked Ford about an engine block heater but they said it should not be necessary.  Ford is going to charge $169 to "diagnose" issues.  This is dealer I bought vehicle new at in 2014.  Is this reasonable?  Obviously I could purchase a better quality battery if I had the $169 to apply to battery.  Any suggestions?

Your 12v battery is very likely in need of replacement. The 12v battery or the jumper cables do not actually start the car but provide power to the relays & such for the HVB to start the car. Since the 12v battery part# is used by a relative few models there is a good chance for getting a "new" battery that has sat on a shelf for several years. Check the build date, not the sell date, before purchase. Build codes are usually molded/stamped into the battery case. You can find translation for codes online. Thanks for the read. 

[CJS]

e information.  From what I can tell, the 2014 Cmax does not have any gauge for the 12 volt battery for a person to monitor it.  Dealer said I did good with it lasting 11 years as they said normally they last 4-5 years.

[fxo]

My 2016 Energi has 143,000 miles on it. I did have the dreaded P0AA6 *(HV system isolation fault) which can be a bad HV battery ($6,000 from Ford just for the battery pack). Instead of a bad HV battery it seems to have been the cabin air pump used to cool the interior and HV battery "box"... they cleared all the codes and since that fix, the vehicle has run several hundreds of miles with out issue. That part was under Ford warranty (as part of the battery and emissions warranty from California CARB, which was 150,000 miles OR 10 years). Whew I was lucky! 

Ford techs at 3 service/parts places say they replace the HV battery mostly when they have gotten wet because of cabin leaks, or other water damage, or when the vehicle has been in an accident. My battery pack still delivers 19 miles of charge at 143,000 miles on the odometer and 8.5 service years of life. I will drive this till the battery or engine dies mostly likely, till 2030 at least when I want to buy a Rivian R3 at that point. These battery packs should last 100-200K miles I would think.

My vehicle is still very fuel efficient, with average driving (plenty of highway) 38 MPG, with mostly electric (around town) I can do much better than that. It is of course a comfortable and practical car as well. Ford made a complicated vehicle but the quality is there.

Edited just now by fxo