随着欧洲和美国新的汽车排放法规的出台，以及为了在激烈的市场竞争中保持领先地位，电动汽车作为减少污染，降低排放的有效手段，已越来越受到人们的重视。进入新世纪以来，美国、日本和西欧的诸多汽车制造商更加大了清洁汽车的开发力度，纷纷投巨资并采取联合结盟的方式开发 With the promulgation of new automobile emission regulations in Europe and the United States, and in order to maintain the leading position in the fierce market competition, electric vehicles have drawn increasing attention as effective measures to reduce pollution and reduce emissions. Since the beginning of the new century, many automobile manufacturers in the United States, Japan and Western Europe have made greater efforts in the development of clean vehicles. They have invested heavily in the development of joint ventures