Today is a full 6 years for me, 40,067 mi, 46.44 Ah, 70% SOH, 50.02 Hx, at 42.8% SOC this morning. I have 9 bars and extrapolated estimate for the 4th bar dropping in Oct 2018, perhaps April 2019 (since there's no measurable degradation from Nov 1 - April 1). No maintenance except new tires, wiper blades, and wiper fluid. Interior is still nearly perfect, paint's a bit dirty, but still in great shape except for that small scrape in it. I typically keep the battery around 40-50% SOC, hoping to improve longevity. While in the PNW, I'm actually in the hottest part, typically 30 day over 100 F each summer. I park in the garage all winter, but outside at night in the summer, again hoping to improve cooling. For all of my extra work, I've extended the battery just slightly, enough to miss the 5 yr, 60,000 mi warranty.
However, the car still meets all of my in-town needs and we still don't have a realistic, 50 mi connection to the WA-OR Electric Highway system that dominates that very slim slice (~10% of the area) along the I-5 corridor. I am hopeful that 2018-19 brings a chance to receive a new battery for less that $2000, otherwise the battery might cost more than the value of the car. In any case, I'll still drive it as long as it has 20 mi range, though I will be disappointed in being required to pay $150/yr for the EV road tax.