Health-conscious energy management of hybrid storage systems for electric vehicles

Abstract

Strong reasons are pushing the automotive market towards producing electrically powered vehicles. Among them, there are regulatory issues related to climate change, customer preference, the oil crisis, and others. Nevertheless, several aspects still prevent a complete transition to electric vehicles leaving behind the classical internal combustion motor powertrain. One of the main aspects still in process of improvement is the energy provision onboard. Actual energetic systems are still costly, bulky, and prone to degradation under normal usage. These aspects weigh negatively on the consumer’s decision when selecting a new vehicle to buy since the final used vehicle’s value when selling it is strongly dependent on the degradation degree of the energetic system, whose replacement cost is a big percentage of the vehicle’s initial value. Also, electric vehicles offering a driving range equivalent to classical internal combustion motor vehicles are heavier, need stronger braking systems, and need more expensive and strong tires, among other issues. This chapter gives an introduction to electric vehicle energetic systems, describing common energy storage and energy sources for electric vehicles such as fuel cell, batteries, and supercapacitors and their main characteristics and aspects to be considered to preserve their lifespan. It gives reasons for the hybridization of the energetic system and reviews the state of the art of common structures of hybrid energetic systems for electric vehicles. Also, reviews the state of the art of energy management system structures based on different design strategies such as model predictive, and rule-based control strategies. Design considerations are exposed, focusing on strategies to split the power demand over the corresponding devices while satisfying healthy usage rules, and/or optimizing a given health-performance index, or other design criteria.