While Joe Biden was busy throttling the latest Corvette with car executives at the Detroit auto show last week, much of the rest of the industry filed into a jam-packed convention center about 30 miles west for a forum the president also managed to rev up.

The Battery Show saw its biggest attendance yet: 15,000 people, up 64% from last year and almost 50% from pre-pandemic levels, according to organizers. One big factor behind all the interest was the Inflation Reduction Act that Biden signed into law last month. Battery upstarts are salivating over the goodies in the bill, particularly the tax credits for manufacturing components here in the US.

Jim Greenberger, the head of a trade association for battery tech in North America, said when he went to the welcome reception, he thought he might be in the wrong room because he didn’t recognize anyone.

“These are all people that suddenly are seeing an opportunity in an industry that’s growing, where there’s substantial government support and everybody’s trying to figure out how they play in it,” Greenberger said.

Kurt Kelty, a Tesla and Panasonic veteran who’s now an executive at battery startup Sila Nanotechnologies, said his company has seen more serious interest from automakers looking to procure battery materials domestically. Same for Mitra Chem, a Silicon Valley company aiming to produce lithium iron phosphate cathodes in the US. There’s a months-long wait list for samples, and the firm is already scouting sites for a new factory, CEO Vivas Kumar said.

While US startups are loving the carrots in the IRA, others are unhappy about the sticks. The auto industry lobbied against content rules that will limit how many EVs will be eligible for consumer tax credits. Korean trade officials have objected to their US counterparts on behalf of Hyundai, Kia and battery manufacturers who fear excluding Chinese-sourced materials and imported cars will put them at a disadvantage. China’s US ambassador showed up at the Detroit show last week to warn against trying to cut the country out of the battery supply chain.

China’s dominance of the space was never far from peoples’ minds at the Battery Show. For all the gold-rush mentality and rhetoric about the power of American innovation, companies are anxious that if the US goes too far in its bid to cut out China, their products could be vulnerable to retaliation.

One panel debated whether the US should create a “white list” similar to what China adopted from 2015 through 2019. The government drafted a list of domestic battery manufacturers whose products were eligible for subsidies. This was key to the rise of Chinese champions like CATL and and a blow to LG Chem and Samsung SDI, which had to repurpose newly built factories in China after being excluded.

The idea was roundly criticized by the panel as un-American.