cartechboy writes: It's like a game of follow the leader. First, Tesla announced its Powerwall Batteries, and now Mercedes-Benz plans to follow suit by entering the energy-storage business as well. A division of parent company Daimler has been testing battery packs that can power houses, and plans to launch commercially in September. Supposedly a battery pack for "light industrial, commercial, and private" use is being tested with sizes ranging from 2.5 kWh to 5.9 kWh. While Tesla's building a massive Gigafactory to make all its batteries for its Powerwall and electric cars, it's unclear exactly how Daimler plans to produce its batteries in a larger-scale energy-storage operation.