10 times higher energy density than lithium battery? Porsche develops silicon anode battery and plans to mass-produce it within 5 years
Spain's "Public" daily website recently reported that battery production is an important source of carbon emissions in the manufacturing process of electric vehicles, accounting for 25% to 40% of total emissions. More and more manufacturers are working to reduce emissions in this area, but Porsche wants to go further. The company is developing a battery with better performance and a smaller carbon footprint. Is this a perfect battery?
Porsche will invest around 1 billion euros over the next 10 years in various decarbonization measures, including reducing carbon dioxide emissions from its assembly plants, the report said. Production of the Porsche Taycan at Zuffenhausen (in Stuttgart, Germany) is carbon neutral from the start, but building a car is much more than assembling all the parts on the production line.
Batteries are one of the important sources of emissions in the production of electric vehicles. In this link, the multiple production steps of converting raw materials such as nickel and cobalt into refined products that can be used in batteries consume enormous amounts of energy.
In a recent press conference, Benjamin Pasenberg, head of high-voltage systems at Porsche, said: "Having green energy is very important, especially in battery production, where it takes a lot of energy to heat things." However, using only Green (or low-emissions) energy sources to make batteries are not enough for Porsche (or other manufacturers) to meet their emissions targets. There is also a need to reimagine the battery itself to reduce the pollution that arises from battery manufacturing practices.
To that end, Porsche is working on a new battery. The battery is said to be more powerful, charge faster, and have a smaller carbon footprint than current batteries. The technology employed is to use more silicon in the anode of the battery, rather than the graphite commonly used today.
According to Otmar Beecher, head of electric vehicles at Porsche, silicon anodes are 10 times more energy dense. Porsche expects 20 to 25 percent more watt-hours per liter of volume than today's conventional lithium-ion batteries. That is to say, under a certain energy capacity, the battery volume is smaller. The improved energy efficiency of batteries, in turn, means fewer batteries are needed to power the vehicle, which reduces overall weight (and also reduces the space required for the batteries).
Less vehicle weight also means lower battery consumption, but where is the positive impact on the environment? First, the design of this new cell reduces the material requirements for the aluminum cell structure (housing) compared to cylindrical cell designs. The production of aluminum is one of the important carbon emission sources for automobiles. According to a recent study by Volvo, aluminum accounts for 30 percent of the emissions that arise from the production of modern vehicle materials, even more than the battery itself. Therefore, reducing the use of aluminum also reduces a large part of the emissions. While no specifics were released, Porsche said the battery would also charge faster.
On the other hand, the cobalt content of such batteries would be reduced. It is now known that cobalt is difficult to obtain, very expensive, and has a great impact on the environment. Cobalt currently makes up 20 percent of the Taycan battery cathode material, and Porsche hopes its new technology will reduce the cobalt share to just 5 to 10 percent.
To further reduce emissions, Porsche will focus on the supply chain. The German company will source cobalt, nickel and other raw materials as much as possible from Europe, so that it will be closer to where the new batteries will be produced, near Porsche's research and development center in Weissach. According to the relevant person in charge of Porsche, purchasing cathode materials from Schwarzheide, Germany instead of my country can reduce carbon dioxide emissions by 25%.
In addition, Porsche is pushing its suppliers to make batteries and other components entirely from renewable energy. The German carmaker said it would no longer consider long-term contracts with suppliers who were unwilling to use certified "green" energy. Porsche says the supply chain accounts for about 20 percent of the automaker's total greenhouse gas emissions. That will rise to around 40 percent by 2030 as production shifts to electric vehicles.
The big question is, when will we see this "ideal" Porsche battery in a road car? Like many other technologies in the automotive sector, it will be used first in racing cars, where high performance and fast charging capabilities are paramount. Otmar Beecher said: "Typically, we are 2 to 3 years away from the transition to production cars. So we will see it in production cars after 2025." Porsche expects to commercialize the high-performance battery within five years.
In terms of production, the goal is to achieve a minimum annual output of 100 MWh, enough to power around 1,000 cars. This leads us to believe that it will initially be destined only for some non-production model, possibly some very high-performance supercar.
Of course, it's not a perfect battery. The perfect battery charges in seconds, doesn't overheat or lose capacity over time, and is lightweight and inexpensive to produce. We'll probably never see a battery with all these features in one, but in the short to medium term, Porsche's battery is getting pretty close to -- at least in theory -- the ideal battery. (compiled / Li Zijian)
