Panasonic will pay ¥403.8bn ($4.6bn) for a 50.2% stake in Sanyo, in a deal that has dragged on for months due to regulatory hurdles in the US, Europe and China. For its money, Panasonic is buying the world’s dominant maker of lithium-ion batteries, and one of Asia’s largest solar-energy players.

Panasonic and Sanyo are decades-long rivals within Japan’s fiercely competitive electronics industry.