Led by former OpenAI CTO Mira Murati, Thinking Machines Lab is one of the hottest AI startups around, having closed a record seed funding round that saw it raise $2 billion at a $12 billion valuation.

In January, there was a lot of hype around an announcement from Finnish company Donut Lab: It claimed to have created the world's first production-ready solid-state battery. But it now appears to be a ...