【摘 要】
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Vehicle makers worldwide are betting big on electric vehicles(EVs).With nations globally mandating sharp reductions in gaso-line-powered transportation [1,2],most leading vehicle manufac-turers,including Volkswagen,General Motors (GM),Honda,Daimler,Ford,V
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Vehicle makers worldwide are betting big on electric vehicles(EVs).With nations globally mandating sharp reductions in gaso-line-powered transportation [1,2],most leading vehicle manufac-turers,including Volkswagen,General Motors (GM),Honda,Daimler,Ford,Volvo,and Nissan-among others-have announced moves to make EVs only or to build them in significantly greater numbers [3-9].With rapid,international growth and standardiza-tion of charging infrastructure,technological improvements,favor-able policies,and falling prices [2,10,11],EVs are approaching a critical threshold.Beyond it,their convenience (the ease of recharging their batteries when needed),range (on a fully charged battery),longevity (tied mainly to battery-pack lifetime),and per-formance are expected to pull ahead of equivalent metrics for com-parably priced internal combustion engine (ICE)-powered vehicles.
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