Measurement of a health index for Li-Ion batteries

Energy independence, reduction of CO₂ emissions and increasing oil prices are the key drivers for the development of new transportation technologies, among which the Battery Electric Vehicles. Instead of representing merely a load, they can provide ancillary services to the power grid: such integration of vehicles into the grid is known as V2G. The continuous charging and discharging of the batteries to provide services to the grid tends to degrade the vehicle batteries, decreasing their maximum life. Therefore it is of interest developing a management strategy that tends to maximize the life of the batteries. To this end it is of fundamental importance being able to assess the state of health of a battery. In this paper a methodology for the measurement of the health is described, and the first experimental results are provided.