Battery/Ultracapacitor (UC) Hybrid Energy Storage Systems (HESS) for Electric Vehicles (EVs) have been frequently proposed in the literature to increase battery cycle life. The HESS consists of a Power Management Strategy (PMS) and an Energy Management Strategy (EMS). Existing EMS are quite empirical, such as setting constant target UC energy levels regardless of load. This work presents an improved complete HESS management strategy. The EMS involves a more comprehensive method of setting the target UC energy level using a speed-dependent band. This allows the UC to achieve two goals – contain sufficient energy for future accelerations and have sufficient space for capturing energy from future regenerative braking – without knowledge of the future drive profile. The PMS involves a speed-dependent battery power limit, which also achieves two goals – better UC utilization and allowing the battery to supply the steady state power. Simulations show existing works cannot achieve the four goals simultaneously unless their UCs are sized twice as large compared to the proposed rule-based HESS. In addition, the proposed HESS extends battery cycle life by up to 42% compared to a battery-only system. Lastly, a reduced-scale experiment was built to show that the proposed HESS is able to run in real-time.

电动汽车（EV）的电池/超级电容器（UC）混合储能系统（HESS）在文献中经常被提出来延长电池循环寿命。HESS由电源管理策略（PMS）和能源管理策略（EMS）组成。现有的EMS具有很强的经验，例如无论负载如何，都设置恒定的目标UC能量水平。这项工作提出了一种改进的完整的HESS管理策略。EMS涉及使用速度相关频带来设置目标UC能量水平的更全面的方法。这使UC可以实现两个目标-包含足够的能量用于将来的加速，并有足够的空间从将来的再生制动中捕获能量-而无需了解将来的驱动曲线。PMS涉及与速度有关的电池电量限制，这还实现了两个目标–更好地利用UC，并允许电池提供稳态电源。仿真表明，现有作品无法同时实现这四个目标，除非它们的UC的大小是拟议的基于规则的HESS的两倍。此外，与仅使用电池的系统相比，提出的HESS可以将电池循环寿命延长多达42％。最后，建立了一个缩小规模的实验，以表明所提出的HESS能够实时运行。