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An electric vehicle battery (EVB) or traction battery is a battery used to power the propulsion of a battery electric vehicles (BEVs). Vehicle batteries are usually a secondary (rechargeable) battery. Traction batteries are used in forklifts, electric Golf carts, riding floor scrubbers, electric motorcycles, full-size electric cars, trucks, and vans, and other electric vehicles. Electric vehicle batteries differ from starting, lighting, and ignition (SLI) batteries because they are designed to give power over sustained periods of time. Deep cycle batteries are used instead of SLI batteries for these applications. Traction batteries must be designed with a high ampere-hour capacity. Batteries for electric vehicles are characterized by their relatively high power-to-weight ratio, energy to weight ratio and energy density; smaller, lighter batteries reduce the weight of the vehicle and improve its performance. Compared to liquid fuels, most current battery technologies have much lower specific energy; and this often impacts the maximum all-electric range of the vehicles. However, metal-air batteries have high specific energy because the cathode is provided by the surrounding oxygen in the air. Rechargeable batteries used in electric vehicles include lead-acid ("flooded", Deep cycle, and VRLA), NiCd, nickel metal hydride, lithium ion, Li-ion polymer, and, less commonly, zinc-air and molten salt batteries. The amount of electricity (i.e. electric charge) stored in batteries is measured in ampere hours or in coulombs, with the total energy often measured in watt hours. The battery makes up a substantial cost of BEVs, which unlike for fossil fueled cars, profoundly manifests itself as a price of range. In the case of the MiEV 2012 model, the price tag and advertised range is close to proportional between two versions with a different battery,〔(【引用サイトリンク】title=Mitsubishi i-MiEV lineup expands for 2012 with cheaper "M" and extended-range "G" )〕 giving the (false) impression that the battery makes up close to 100% of the cost (95% for the higher priced version). However, some of the price difference comes from extra features in the higher priced version, plus an unknown price premium, making such a retail price comparison a very bad indicator of actual cost of battery capacity, but nevertheless serves to quantify battery capacity as a premium feature. The few electric cars with over 500 km of range (including Tesla Model S with the 85 kWh battery), are firmly in the luxury segment, as of 2015. Since the late 1990s, advances in battery technology have been driven by demands for portable electronics, like laptop computers and mobile phones. The BEV marketplace has reaped the benefits of these advances. However, Mitsubishi ascribes the price reduction of its 2012 model MiEV, compared to the 2011 model, to "a dramatic reduction in the cost of batteries".〔 The cost of electric vehicle batteries has been reduced by more than 35% from 2008 to 2014.〔(【引用サイトリンク】title=Vehicles - Department of Energy: Energy.gov )〕 Rechargeable traction batteries are routinely used all day, and fast–charged all night. Forklifts, for instance, are usually discharged and recharged every 24 hours of the work week. The predicted market for automobile traction batteries is over $37 billion in 2020.〔(【引用サイトリンク】title=Car Traction Batteries - the New Gold Rush 2010-2020: IDTechEx )〕 On an energy basis, the price of electricity to run an EV is a small fraction of the cost of liquid fuel needed to produce an equivalent amount of energy (energy efficiency). The cost of replacing the batteries dominates the operating costs.〔http://cet.berkeley.edu/dl/CET_Technical%20Brief_EconomicModel2030_f.pdf".The 2012 per-mile cost under this scenario will be 10c/ per mile. If the batteries are able to achieve 3,000 100 mile charge cycles and the vehicle is driven 15,000 miles per year, the 2012 per-mile cost is approximately 6.7c/ per mile.28 The likely lifetime of electric vehicle batteries is likely to fall somewhere within this range. The cost of electricity for electric cars is on the order of 2c/ per mile"〕 == Battery types == (詳細はウィキペディア（Wikipedia）』 ■ウィキペディアで「Electric vehicle battery」の詳細全文を読む スポンサード リンク
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