Why do people think electric cars are somehow better for the environment?

Help me understand how electric cars are better than traditional internal combustion powered vehicles? Sure you don’t have emissions coming out of the tailpipe. But the electricity used to charge the battery has to come from somewhere, namely a power plant. And if everyone switched to these electric vehicles then we’re going to need a whole lot more power plants, far more tham wind or solar could support. But the worst thing to come from electric cars is the batteries. Do people not understand what goes into making batteries? What’s required? Now imagine how many of these batteries would be required to meet the transportation needs of the country. And then there is the issue of disposal/recycling of old batteries. The more I think about it, the more the notion of electric cars being “better” for the environment looks absurd.