tailieunhanh - Fast Charging

Increased environmental concerns and fuel costs have made a significant impact on transportation technology, as a result of which advanced vehicles with enhanced fuel economy and less emission have started to penetrate the market and have gained popularity. | Fast Charging V Svoboda Huntsville AL USA 2009 Elsevier . All rights reserved. Introduction Increased environmental concerns and fuel costs have made a significant impact on transportation technology as a result of which advanced vehicles with enhanced fuel economy and less emission have started to penetrate the market and have gained popularity. The current market offers hybrid electric vehicles HEVs which combine internal combustion motor with electric drive train and battery energy storage. Electric vehicles EVs with only electric drive train and battery energy storage have never grown over the prototyping and testing phases. Although the state-of-the-art HEVs provide enhanced fuel economy in order for them to significantly influence global fuel consumption and the environmental situation they need to be developed further. One of the approaches is moving from micro-HEVs to plug-in HEVs which have increased utilization ratio of the electric drive train. Technically besides other advancements the main development tasks should focus on high-capacity batteries with fast charging abilities and fast charging techniques. Such development might also trigger utilization of EVs in the future. There is no single definition of fast charging. Generally any technique that provides charge duration of less than 1 h at charge rate 1 C is considered to be fast charging. The importance and difficulty of fast charging may be represented by comparing with conventional gasoline tank filling in which about 90 kWh of energy is stored in a vehicle in a couple of minutes. A conventional single-phase household charger delivers about 30 kWh in 10 h. This article focuses mainly on fast charging of advanced lead-acid and nickel-metal hydride Ni-MH batteries. Lead-acid batteries have very low internal resistance which makes them favorable for high charge and discharge rates. Nickel-metal hydride batteries have higher capacity density and cycle life than lead-acid batteries. Although the .