Solid state batteries promise 2x higher energy density than traditional lithium ion, with 3x faster charging and lower risk of fires. Thus they could re-shape global energy, especially heavy trucks. But the industry has been marooned by uncontrollable cell degradation. QuantumScape’s disclosures suggest it is light years ahead. Many of its claims are supported by patents. But costs may remain high. These are the conclusions in our new 20-page report.