Lucid Group Inc (LCID.O), backed by Saudi Arabia's sovereign wealth fund, struggled to build its sleek Air luxury EVs.Industry executives and forecasters do not agree on how rapidly electric vehicles could take over half the global vehicle market, let alone all of it.Among the barriers to EV adoption, industry executives and analysts said, were a dearth of public fast-charging infrastructure, and the rising cost of EV batteries, driven by shortages of key materials and uncertainty over government subsidies that have buoyed EV purchases in major markets including the United States, China and Europe.Electric vehicle sales likely will not increase in a smooth, ever-ascending curve, said AFS President Joe McCabe.Based on automakers' product plans, Wards analyst Haig Stoddard said at a recent conference that manufacturers "expect strong ICE (internal combustion engine) volume heading into the next decade.""