Stem attracts funds for battery systems

Energy storage firm Stem has raised $68 million in a third round of funding from Mitsui & Co.; Mithril Capital Management, the investment fund of PayPal founder Peter Thiel; and others. Stem has installed grid-integrated lithium-ion battery systems for 440 businesses in California and Hawaii. The systems include so-called smart software that learns a customer’s energy profile, enabling it to switch between grid and stored energy to reduce costs. The systems can also sell energy back to the grid.