Two sheets of graphene — carbon film one atom thick — without a twist resemble a harbor clogged with shoals: lithium ions either run aground or rush past without stopping. But a 9.43° twist lays out a perfect fairway. The ion ships dock securely to carbon 'piers' and immediately cast off without losing speed.

The driving force is entropy — the eternal push toward disorder — urging ions to spread like water across a table. The principle of twisting lattices was first applied by Leo Esaki to semiconductors, and now machine learning finds safe 'straits' in molecular structures without long calculations, like a pilot reading a map.