Abstract
In in-use hybrid electric vehicles (HEV) of 100,000km or more driving, fuel economy performance would change due to the deterioration of hybrid batteries. If a life cycle CO2 emission from HEV is estimated, the deterioration of fuel economy performance of HEV should be considered. So we conducted fuel consumption measurements of JC08 mode 60km/h constant driving with a HEV of 187,000km driving, and the performance of battery cells were investigated also. From the results, though the deterioration of battery capacity was 20-30%, fuel economy of JC08 mode changed about 2.5%.
