Battery life is all linked to charging cycles in terms of discharging etc. I think you'll find most of the hybrids have software monitoring these types of things. As some of you'll know my daily runner is a hybrid so I did look at this.
I read somewhere a few days back that a number of the mainstream manufacturers are pulling out of the electric market due to cost of production and uptake. I still fancy a wind turbine or solar panels at home linked to a micro hydrogen generation plant.