Battery as a Service for Electric Vehicles: Design and Optimization of Partially Swappable and Shareable Battery System

The major challenges for electric vehicle deployment include the prohibitive battery cost and a large amount of time required for energy refueling. Although the concept of battery swapping can solve the latter problem, it is difficult to overcome the former problem while ensuring a long-range drive. Thus, this paper reports upon a conceptual electric vehicle (BaaS-EV) that shares a part of the battery and presents an optimization model for its service infrastructure, battery as a service (BaaS). The BaaS-EV has two different batteries and operation modes. For short-range drive, the BaaS-EV can be driven using only one of the batteries, and to operate in a long range, an additional shared battery can be employed. Such shareability can increase the utilization rate of the battery and reduce the battery cost. The BaaS infrastructure provides BaaS-EV users with recharged batteries on demand. A cost-efficient operation of BaaS requires simultaneous optimization of the number of batteries, charging techniques, and transportation costs. To realize this aspect, an optimization model is established based on the minimum cost flow problem. Results of numerical simulations and case studies based on the model highlight the possibility of cost-benefit pertaining to the battery, user opportunity, battery charging, and transportation costs.