U.S. efforts to build a national network of electric vehicle charging stations are moving slowly as states figure out how to fairly dole out public funding to kick-start a new service industry. As the Biden administration prepares to give states $7.5 billion for new charging stations, a similar recent effort suggests a difficult path is ahead. States received $424 million that could be used for charging stations as part of a $2.8 billion settlement by Volkswagen to resolve allegations that it cheated on diesel emissions tests. So far, more than four years later, they have spent about 48% of those charging dollars.