Ions in your tank

You can’t smell them and you can hardly hear them — but electric vehicles are indeed already on the road in many cities around the world, as climate change and dwindling oil reserves are causing societies to rethink the concept of mobility. As such, engineers around the world are now hard at work to “electrify” the automotive industry. However, electric vehicles only truly become climate protection units on wheels when the electricity they use is generated from renewable sources such as the sun, wind, and biomass. Innovative concepts could soon be paving the way for an electric mobility breakthrough, as a study conducted by TÜV SÜD has found that the willingness of drivers to switch over to electric cars has never been greater than it is now.

Still, electric vehicles won’t become economically attractive to consumers until some major technological challenges involving batteries are overcome, for example. The major weak point here has to do with the storage of the electricity needed to power the drive system, as conventional nickel metal-hydride batteries are too large and heavy, and not sufficiently long-lasting, to be used for electric mobility applications. Moreover, the additional costs they generate for the battery package alone can total tens of thousands of euros.

“One alternative is offered by lithium-ion batteries that already supply power to cell phones, laptops, and navigation devices,” says Dr. Michael Schmidt, Project Manager for lithium-ion batteries at Merck. These batteries basically consist of four parts: a negative electrode (anode), a positive electrode (cathode), a separator, and an electrolyte. “When the cell is charged, lithium ions move from the cathode to the anode via the electrolyte and the separator,” Schmidt explains. “The process then reverses during discharging, whereby the ions release electrical energy.” In June 2009, the Mercedes S 400 Hybrid became the world’s first series-produced car on the market to be equipped with Li-ion batteries.

Now, German Federal Minister of Research, Annette Schavan, has announced she wants to turn the country “into the world’s leading market for electric vehicles.” To promote this transformation, the German federal government is investing more than €700 million in the period 2005–2013. Researchers from Merck are also working on several associated projects simultaneously with the goal of lengthening batteries’ service life and raising their energy density. The German Federal Ministry of Education and Research (BMBF) is expecting big things from Merck here: “We want to produce the world’s best electric cars in Germany in the future,” says Andreas Storm, a parliamentary secretary at the BMBF. “The key component in these vehicles will be reliable high-performance batteries, to whose development Merck can make a major contribution.”