10.7 miles at 3.7 kwh is certainly indicative of either overly aggressive driving behaviors (hard acceleration and braking), energy wasting behaviors (hvac and high speeds), or unfavorable environmental factors (hills, cold, etc) or a combination of them.
Similar to Raja, my driving style and conditions typically afford me about 4.5mi/kwh and under ideal conditions it can be as high 5.5mi/kwh. You're getting 2.9mi/kwh. That is very low especially considering it's not very cold yet (not entirely sure on your climate is though) and you said you had hvac off. Hills and cold weather you can't help, but you can adjust your driving style.
Whether or not Ford should warranty any and all battery degradation is debatable. Some degradation is expected and Ford should not be on the hook for modest and gradual capacity losses IMHO. However, 3.7 kwh down from a more realistic 5.4 kwh (like new to the point of hybrid mode switch over) is a pretty substantial loss of capacity. I'm not sure what a reasonable warranty claim loss should be, but 80% of original capacity seems to be the definition most academic literature is using for "useful life". Even if you went with a more Ford favoring threshold of 70% you'd still be under that. Just thinking out loud right now...
Edited by bdginmo, 04 November 2016 - 07:26 AM.