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The thermal management of the batteries in electrical and hybrid vehicles is a major concern for operation safety, battery life, and performance. In the current research, the temperature of the battery is tracked for 10,000 s of operation while using a Ranque–Hilsch vortex tube (RHVT) for the thermal management of the battery. An analytical model is developed and validated to study the impact of the heat generated per unit volume from the battery, the mass ratio for the cold air at the outlet to the total air at the inlet (x), entered air pressure, temperature, and mass flow rate. The peak temperature of the battery can be reduced by increasing the pressure and mass flow rate of the air at the inlet, decreasing the temperature of the air at the inlet, and using four RHVTs instead of a single RHVT. The proposed system significantly decreased the maximum temperature of the battery to 48.12 °C, compared to the battery thermal management method of using direct air, which resulted in a temperature of 75.73 °C. Furthermore, employing four RHVTs to cool the battery further reduced the maximum temperature from 48.12 to 11.23 °C, demonstrating a substantial improvement compared to utilizing a single RHVT. Utilizing the RHVT provides a good solution for the battery thermal management problem because it is cheap, small, and reduces the temperature of the air rapidly. [ABSTRACT FROM AUTHOR]

A revolution is underway in transportation, with a variety of electric vehicles rapidly coming to the fore. The switch from internal combustion engines to electric motors will change the world in many ways and is expected to help reduce the world’s carbon dioxide emissions. Inspired by this vision, leaders in China, France, and Britain have all proclaimed that they will effectively ban cars that aren’t electric by about 2040, while Volvo says all of its vehicles will be powered by electric motors in a few years. Other automakers have also announced that they are headed that way. But how far along is this revolution really? What challenges still need to be overcome to gain truly widespread acceptance on a scale that can combat climate change? Will the costs and the benefits of these new vehicles be equally spread among countries and companies? And while we all benefit in the long term, who will be the winners and the losers in our short-term world where Wall Street thinking predominates? [ABSTRACT FROM PUBLISHER]

Abstract: Reducing or eliminating the dependency on petroleum of transportation systems is a major element of US energy research activities. Batteries are a key enabling technology for the development of clean, fuel-efficient vehicles and are key to making today''s hybrid electric vehicles a success. Fuel cells are the key enabling technology for a future hydrogen economy and have the potential to revolutionize the way we power our nations, offering cleaner, more efficient alternatives to today''s technology. Additionally fuel cells are significantly more energy efficient than combustion-based power generation technologies. Fuel cells are projected to have energy efficiency twice that of internal combustion engines. However before fuel cells can realize their potential, significant challenges remain. The two most important are cost and durability for both automotive and stationary applications. Recent electrocatalyst developments have shown that Pt alloy catalysts have increased activity and greater durability than Pt catalysts. The durability of conventional fluorocarbon membranes is improving, and hydrocarbon-based membranes have also shown promise of equaling the performance of fluorocarbon membranes at lower cost. Recent announcements have also provided indications that fuel cells can start from freezing conditions without significant deterioration. Hydrogen storage systems for vehicles are inadequate to meet customer driving range expectations (>300miles or 500km) without intrusion into vehicle cargo or passenger space. The United States Department of Energy has established three centers of Excellence for hydrogen storage materials development. The centers are focused on complex metal hydrides that can be regenerated onboard a vehicle, chemical hydrides that require off-board reprocessing, and carbon-based storage materials. Recent developments have shown progress toward the 2010 DOE targets. In addition DOE has established an independent storage material testing center to verify storage capacity of promising materials. These developments point to a viable path to achieving the DOE/FreedomCAR cost and performance goals. The transition to hydrogen-powered fuel cell vehicles will occur over the next 10–15 years. In the interim, fossil fuel consumption will be reduced by increased penetration of battery/gasoline hybrid cars. [Copyright &y& Elsevier]