The audience sat patiently through the presentations about the cluster of battery factories going up nearby. They listened to descriptions of the hazardous chemicals the plants will use, their huge water withdrawals and energy demands. When it came time for questions, people began shifting in their chairs and standing up, making the cramped room feel even smaller. A third warned it would be just like the Soviet era, when iron and steel plants left a polluted legacy. The Chinese battery giant Contemporary Amperex Technology Co., or CATL, is nearing completion on what could be one of Europe’s largest electric vehicle battery factories.