my wife has had her civic hybrid since 2004; almost 300k miles and no battery replacement has been needed. since she liked hers so much I purchased a 2011 civic hybrid and now have 174k with no problems beyond tires and brakes. It averages 43.9 mpg combined city and freeway driving and has needed no battery replacement, besides engine battery. We even filled my car with tent, cooler, stove etc and went camping for a week in Glacier National Park very comfortably. Very happy with Honda hybrids.