Bosch is investing €400 million (US$455 million) per year in electromobility; part of that investment is researching batteries with twice the energy density at lower costs than available today by 2020. Driving the investment is Bosch’s expectation that ten years from now, some 15% of all new vehicles worldwide will have an electrical powertrain.
Dr. Thorsten Ochs, head of battery technology R&D at the new Bosch research campus in Renningen, says that to achieve widespread acceptance of electromobility, mid-sized vehicles will need to have 50 kilowatt hours of usable energy. With conventional lead batteries, this would mean increasing the weight of the battery to 1.9 metric tons, even without wiring and the holder, he notes. Today’s lithium-ion batteries are superior in this respect, storing more than three times the amount of energy per kilogram.
At a weight of 230 kilograms, the battery of a modern-day electric car provides approximately 18 to 30 kilowatt hours. But to achieve the desired 50 kilowatt hours, a battery weighing 380 to 600 kilograms would be necessary.
Dr. Ochs’ goal is to pack 50 kilowatt hours into 190 kilograms. In addition, the researchers are looking to significantly shorten the time a car needs to recharge. “Our new batteries should be capable of being loaded to 75 percent in less than 15 minutes,” Ochs says.
Ochs and his colleagues believe that improved lithium technology will make it possible to achieve these goals. To make progress in this area, his team in Renningen is working closely with Bosch experts in Shanghai and Palo Alto. And as a further measure to advance lithium-ion battery research, Bosch has established the Lithium Energy and Power GmbH & Co. KG joint venture with GS Yuasa and the Mitsubishi Corporation.
Using lithium instead of graphite in the anode would make it possible to store up to three times as much energy in the same space. Ochs and his colleagues have already developed approaches for removing the graphite and replacing it with other materials. Bosch CEO Volkmar Denner also recently presented a prototype solution at the IAA. Thanks to its purchase of Seeo Inc., a start-up based in Silicon Valley, Bosch has now acquired crucial practical expertise when it comes to making innovative solid-state batteries. (Earlier post.)