2017 Fusion Hybrid Battery Life

[Airlocker33]

Question:  Thinking about buying my 2017 Ford Fusion Hybrid SE  from my company because its time to trade in and they are selling at auction price.  The car has 120K miles on it buy i'm curious as to how long the Battery packs will last.  Does anyone have an idea, if so please let me know so I can buy or pass on the deal.  

[murphy]

The High Voltage Battery is supposed to last for the life of the car.  The 12 volt battery will need replacement just like any other car.

 

[Airlocker33]

replaced the 12 volt battery in the trunk a year ago, so that answers my question  

[mwr]

2 hours ago, Airlocker33 said:

replaced the 12 volt battery in the trunk a year ago 

I'm curious why the 12v battery on a 2017 model needed replacing a year ago.

[2014FordFusionSE]

1 minute ago, mwr said:

I'm curious why the 12v battery on a 2017 model needed replacing a year ago.

 

I was thinking the same thing. My 2014 still has its original battery though only 49k miles on the car.

[mwr]

2 hours ago, 2014FordFusionSE said:

 

I was thinking the same thing. My 2014 still has its original battery though only 49k miles on the car.

My 2015 was one of the first ones, bought in October 2014, so it's almost 5 1/2 years old with 75K miles. No problem at all with the 12v battery.

[ElectricFan69]

On 2/11/2020 at 8:12 PM, mwr said:

I'm curious why the 12v battery on a 2017 model needed replacing a year ago.

The accessory battery life can get cut short by doing things like sitting in car with radio playing and the system in 'accessory' mode, for extended periods of time.  Ford seems to have covered the normal things that kill the lead/acid battery  like leaving the lights on to the point of the battery going flat.

The conventional 'wet' cell (contrasted with AGM) does not tolerate repeated deep cycling well.  In 'by the book' use, it will likely last a decent amount of time. 
On our TCH, my daughter got into the habit of sitting in the student parking lot with the radio playing on a regular basis.  The accessory battery died after about 9 months of this treatment.  Now, the car was 8 years old at the time, and it had the Panasonic AGM battery but still.

[VILSIS]

My 12v battery had to replaced in warranty on my 2018 Fusion Hybrid after 27 months and 5,127 miles.  The reason was, I use the car to less and mostly only in the town. Now I have a Battery Tender and when I but the car in the garage I connect the Battery Tender to my 12v battery. I hope this way my battery hold several years longer. 

[Isaacclarke2465]

My high voltage battery started a power declination around 150,000 miles. It is simple to replace.  In my experience of the whole situation, I started out just for funsies asking the dealership for a quote on replacement.  They came back with over $5000 just for the freaking battery! Not including any labor. I purchased a high voltage hybrid battery for my 2017 Fusion from Ebay at a cost of around $2000. This included price of the battery, plus freight, plus core. Donor vehicle was a 2019 with around 35,000 miles on it. (Very important to know the miles the battery has on it if purchasing used.) Most importantly if you are any kind of mechanically inclined you can do a battery swap in around 3 hours yourself. It helps if you do a little internet searching and download the official Ford hybrid battery removal PDF. If you are careful and go step by step, your car will run like its brand new. In addendum, no relearn process is required.  Its as easy as changing a few AA's. Save yourself thousands, its a process anyone can do.

Edited February 22, 2023 by Isaacclarke2465

[MeeLee]

2019 ffh se, used to do 75 nearing 80mph on electric, but started declining rapidly after complete battery draining by mechanic (turned ac up to max, and left car on) at 94k miles.

 

At 115k miles, the battery now can only provide enough power for 60mph on electric. The electric range has also declined a lot.

 

To compensate, I put on 1inch larger tires, pumped at 45-49PSI (rated for it, causing less road noise, yet same mpg as stock tires). I then replaced the 12v battery with a lithium SLA (deep discharge) type of battery. It allows for much more efficient charging.

I did have to manufacture a 2 way diode (2 diodes in parallel redirecting the current in opposite direction), to allow the car to think its a standard lead acid battery.

The diodes cause a voltage drop of 0.6V (both ways), as the car charger sometimes exceeded the max charge voltage for the lithium battery, and the bms would just cut out.

 

Now, the battery sees 14.1V charge voltage instead of 14.7V, and the car sees 12.7V instead of 13.36V from the battery.

 

The battery is a "12V" (>13.3v) 50Ah battery.

 

I first tried with a 10Ah ups battery, with 20Ah peak current for up to 10 seconds, but that battery wasn't able to start the car. I would estimate, the car needs at least 35Ah (also sold on amazon), but I went with the largest battery that would fit (50Ah).

 

The new battery increased my electrc driving range and overall mpg by about 2mpg, by reducing the load on the high voltage battery. Works mostly when I'm driving longer distances (most of the time exceeding 45 mpg); while short distances are ~40mpg now.

 

My estimation is that my high voltage battery will last about until 133k miles, before mpg will drop from 48mpg new, to ~45mpg now, to 40mpg.