By Elizabeth Pineau, Gilles Guillaume and Michel Rose PARIS – For French President Emmanuel Macron, it was a light-bulb moment. In an ornate ballroom at the Palace of Versailles last July, the head of Taiwan's ProLogium took out a pair of scissors and cut one of its solid-state batteries the size of a credit card in half. The small bulb it was powering continued to shine. Macron was amazed by the demonstration of the safety and durability of the next-generation technology many carmakers hope will soon power electric vehicles (EVs), according to two people at the meeting. "We'll make your…