In recent years, hybrid electric vehicles (HEVs) have increased significantly due to climate change and the demand for high-efficiency power sources. HEVs that combine an internal combustion engine (ICE) and an electric motor (EM) can improve the power output of the ICE and overcome the challenges of the insufficient battery life of electric vehicles. In this study, a parallel HEV with a power distribution mechanism is developed for energy saving and carbon reduction. The driver′s power demands are used as input sources, and a rule-based control strategy is used to determine the power distribution of the generator, EM, and ICE. The NEDC2000 driving cycle is used as the test benchmark to demonstrate the performance of the HEV. In comparison to ICE vehicles, the fuel efficiency of HEVs significantly improved. In addition, other parameters, including the average brake-specific fuel consumption (BSFC), brake-specific carbon monoxide emission (BSCO), and brake-specific hydrocarbons (BSHCs), were lower, which can effectively save fossil fuel and reduce air pollution.

This research examined the operation of zinc–air fuel cell (ZAFC) with two different anode fuel types, namely zinc plate and zinc particle. The cell operation with zinc particle fuel also included potassium hydroxide (KOH) as the flowing electrolyte, and the optimal electrolyte flow rate was established as 150 mL/min. The performance of the two cells was compared in terms of power performance and reduction in reactor internal resistance. The power performance evaluation depends on three main factors including open-circuit voltage (OCV), power, and current density. The ZAFC with particle fuel was better than the plate-type fuel cell with maximum OCV of 1.41 V and current and power density values of 684 mA/cm² and 553.6 mW/cm², respectively. The particle fuel cell with flowing electrolyte also showed better reduction in external ohmic resistance, kinetic resistance, and mass-transport resistance with values of 0.41, 0.14, and 0.19 Ω, respectively, but a slight increase in internal resistance of the particle ZAFC (0.20 Ω) over plate anode fuel cell (0.18 Ω) was observed. Nyquist and Bode plots were used to explain the results in this study.

The flowing electrolyte in a zinc-air fuel cell (ZAFC) can reduce the problem of incomplete reaction caused by the concentration gradient of the electrolyte. In this study, we propose a self-developed ZAFC with a flowing electrolyte system and optimize control parameters. The anode of the ZAFC used Zn particles through which the electrolyte penetrates and combined with a negative pressure pump to allow the potassium hydroxide (KOH) electrolyte to have an effective chemical reaction with the Zn particles during the discharge process. However, the flow rate of the electrolyte is required to match other control parameters, such as operating temperature, KOH concentration, and cell size, to effectively improve the efficiency of ZAFC. Therefore, the Taguchi method is adopted to obtain the optimal reaction parameters and the key factors affecting the discharge efficiency of the cell. The best operation condition is the temperature at 50°C, the KOH concentration of 30% wt, and the electrolyte flow rate of 150ml/min; then, the maximum power obtained from the experimental results is 13.8 W, the maximum current density reaches 699.721mA/cm², and the maximum power density is 395.037 mW/cm². This paper provides valuable insights for the upgrade of ZAFC for future practical applications.