In the "Center for Research and Advance Engineering" in Renningen, just outside Stuttgart, around 1700 creative people will be working in research for Bosch in the future. 14 buildings with a total usable area of 110,000 square meters have been constructed on the 100-hectare site. The first offices were occupied in summer 2014, and the campus is due to be completed in October 2015 after a four-year construction period. However, the office itself is no longer the focus, and the classic individual office is becoming less important as a workplace. In its place is the ability to work wherever you want: indoors or outdoors, alone or with others. Thanks to comprehensive WLAN, laptop and mobile device equipment, the entire campus will become a workplace, Bosch announces. To mark the opening of the new campus, the e-bike drive manufacturer with its main pillar in the automotive industry is also revealing the areas in which research is being conducted in Renningen.

Storing twice as much energy in 2020
Bosch is researching batteries there that will enable longer rides without recharging and at the same time cost less. "Our battery experts are creating a key prerequisite for the breakthrough of electromobility," promises Dr. Michael Bolle, Chairman of the Board of Management of the Research and Advance Engineering division at Robert Bosch GmbH. As early as 2020, Bosch batteries should be able to store more than twice as much energy while costing significantly less. The market forecasts are corresponding: Bosch expects around 15 percent of all new vehicles worldwide to have an electrified drive in ten years' time. This is why the company is investing 400 million euros a year in electromobility.

Current challenge: high weight, low energy density
Dr. Thorsten Ochs, Head of Battery Technology Research at the new Bosch research campus in Renningen, explains how the necessary advances in battery technology are to be achieved: "For electromobility to be widely accepted, we need a usable energy of 50 kilowatt hours in a mid-range vehicle." If this were to be achieved with conventional lead batteries, the storage units would weigh 1.9 tons, even without cabling and mounting. That's how much today's mid-range limousines weigh - with passengers and luggage. A conventional lead-acid battery - as found in almost every car today to supply the starter motor with electricity - stores 0.5 kilowatt hours of energy at a weight of 19 kilograms, which is comparatively little.

The goal: only 190 kilograms in weight and charged in 15 minutes
Current lithium-ion batteries are better. They store more than three times the amount of energy per kilogram. At best, the battery of a current electric car weighs 230 kilograms and delivers up to 30 kilowatt hours. To achieve the desired 50 kilowatt hours with this energy density, at least a 380 kilogram battery would be required. Ochs and his international Bosch colleagues are therefore working on even more powerful energy storage systems. The goal: to fit 50 kilowatt hours into 190 kilograms. The researchers also want to significantly reduce the time a vehicle needs to recharge. "Our new batteries should be able to be charged to 75 percent in less than 15 minutes," says Ochs. Ochs and his colleagues are convinced that these goals can be achieved with improved lithium technology. "There's still a lot to do and improve when it comes to lithium," says Ochs. His team in Renningen is working closely on this with Bosch experts from Shanghai and Palo Alto in Silicon Valley. Bosch has also founded a joint venture with GS Yuasa and the Mitsubishi Corporation to drive lithium-ion battery research forward.

MMore space for electrical energy - thanks to start-up technology
In theory, the solution sounds simple: "The more lithium ions fit into a battery, the more electrons and therefore energy can be stored in the same space" continues Ochs. However, the practical implementation is challenging, as the researchers have to improve cells at the atomic and molecular level. A key to this is reducing the graphite content or eliminating the graphite in the anode. If metallic lithium were used instead of graphite, significantly more energy could be stored in the same space. Together with his colleagues, Ochs has already developed several approaches as to how the graphite could be removed and which materials are required for this. With the purchase of the US start-up Seeo Inc., Bosch now has decisive expertise in the implementation of new types of solid-state batteries. According to the e-bike system supplier, these have another decisive advantage: they do not require liquid electrolytes, which are contained in conventional lithium-ion batteries and can lead to safety problems under unfavorable conditions.

www.bosch-renningen.de