Optimal battery capacity for an electric-vehicle-sharing-model in the People’s Republic of China

Abstract

A project on electric vehicle sharing has been previously carried out as a demonstration operation in Shanghai, Beijing, Hangzhou and Shenzhen in the People’s Republic of China. The high initial investment caused by the high cost of batteries limits commercialization of an electric-vehicle-sharing model. Therefore, a key problem that the operators must solve is to choose the appropriate battery capacity for shared electric vehicles based on different urban driving cycles. Based on three new energy vehicles (i.e. electric vehicles) for demonstration cities of different scales as represented by Shanghai, Shenzhen and Hefei, a whole-life-cycle evaluation model of economic benefits for shared battery electric vehicles was established in this paper. The optimal battery capacity for different substitution rates was calculated using MATLAB software. Then, the influences that the substitution rate, the urban driving cycle, the average daily travel distance, the service price, the charging price, the battery (cycle) life, the battery pack cost and the government subsidy have on the optimal battery capacity in the life-cycle economic benefit model was explained. Suggestions for the optimal battery capacity are provided for operators in different cities. The results indicate that the purchasing cost, the energy consumption cost and the battery depreciation cost are the three main components of the life-cycle cost, which account for more than 80%. The average daily travel distance and the local government subsidy affect the optimal battery capacity only for certain substitution rates. The life-cycle economic benefits of one shared electric vehicle is found to have the most influence on the service price. This paper suggests that shared battery electric vehicles with different battery sizes of 44.5 kW h, 34.9 kW h and 36.96 kW h are suitable for use in metropolitan cities, in large-sized to medium-sized cities and in medium-sized to small-sized cities respectively, as represented correspondingly by Shanghai, Shenzhen and Hefei.