ALEXANDRIA, Va.—There is a push across the U.S. to speed up electric-vehicle charging, reports The Wall Street Journal.

The U.S. government is attempting to ignite the buildout of fast chargers that can charge EVs in about 15 to 40 minutes, and automakers are attempting to improve EV batteries to increase charging times, as the EV industry believes that super-fast charging is needed for widespread EV adoption. Experts believe that fast charging will mitigate range anxiety in consumers.

However, other experts argue that the key to EV adoption is slower chargers, but more of them, in places where people park for longer, such as offices, restaurants, shops and apartments.

Currently, the majority of EV charging takes place at home—and that’s likely to continue—according to the Journal. The typical EV consumer has been higher-income homeowners with a garage where they can slowly charge for hours.

Fast chargers can charge a battery to 80% in 15 minutes at the higher power level, and it takes about an hour at the lower power level, depending on the EV battery’s charging rate. However, only a few higher-end passenger EVs have the capacity to take advantage of these fast chargers.

Although faster, and more convenient, fast chargers require more infrastructure, and they are more expensive.

“Higher power costs more,” Bowermaster told the Journal. “You get to a point where, for these higher power levels, you’d need bigger and bigger wire. At some point the wire gets so big that not only it’s heavy, but it can’t readily bend to curve around the charging port.”

One solution to speeding up charging is the battery itself. Solid-state batteries have an electrolyte that conducts the electric current in a solid form as opposed to liquid, which is used in most batteries today.

Nick Nigro, founder of the research group Atlas Public Policy, expects the passenger-car market to move toward a standard of 350-kilowatt charging. “It’s not clear that there’s going to be much value in going much higher than that for regular passenger vehicles,” he told the Journal.