In the future, electrically powered cars are expected to play a key role in improving the air quality in metropolitan areas and reducing CO2 emissions. As a consequence, the increase in e-fleets and thus also battery capacities is being pushed on a global scale – and especially in China. For manufacturing the key component of these energy storage devices, the so-called battery electrode slurry, Bühler has in the past years joined forces with the Chinese manufacturer Lishen and developed an entirely new and much more efficient production process – and has now been awarded the first large-scale order by Lishen for four production lines worth almost CHF 10 million. “For us, this order means that we have entered the rapidly growing market of the future of e-mobility,” explains Samuel Schär, CEO of the Bühler Advanced Materials Business.

The growth in the world’s population and the increasing prosperity especially in the emerging countries is producing a vehicle density never seen before. Today, China with its output of more than 20 million cars per year is the world’s largest automobile manufacturer. But in particular in densely populated cities, motorized traffic poses a great challenge. Electrically powered cars therefore stand to make a substantial contribution to cutting CO2 emissions and thus to ensuring clean and efficient mobility. Moreover, the Chinese government is promoting the propagation of electrical vehicles on the basis of a number of targeted measures. In order to meet the requirements of this expected boom, battery manufacturers are currently ramping up capacities on a massive scale too.

One of the largest battery manuafacturers in China is Lishen, which was set up in 1997. The company with 10.000 employees specializes in the development, production, and sale of lithium-ion batteries for electrically powered cars. Lishen plans in the next few years to commission three new battery factories in China. Their combined annual capacity will amount to 40 gigawatt-hours – more than the global production capacity for lithium-ion batteries in 2013 and sufficient for 700.000 average car batteries.

One of the core components of these batteries are the materials of the positive and negative pole (so called anode and cathode) – which store the lithium-iones in their porous structure. The processing of these materials have a direct impact on the efficiency, performance, and capacity of lithium-ion batteries. However, the methods used today for this purpose are unsuitable for handling the ever-larger production volumes. Therefore, in close partnership with Lishen, Bühler has developed an entirely novel process over the past years which allows continuous production using a twin-screw extruder – to date, the slurries were mixed batch by batch in large agitator vessels. The new Bühler process enables a much more consistent quality to be achieved, takes up 60 percent less space, and reduces the process energy demand by 60 percent – thus slashing significantly the production cost of the batteries. “These efficiency increases in the production of the key components are crucial for propagating electric mobility on a large scale,” says Cornel Mendler, Head of the Bühler Business Area Grinding & Dispersion.

The Lishen investment of just under CHF 10 million equals a capacity sufficient for an hourly battery output for about 30 electric cars or 3200 e-bikes – for a whole year, this translates into almost 20 million e-bike batteries or more than 150,000 electric vehicle batteries. “After long years of joint research and development efforts, this for us is the breakthrough into the world of large-scale commercial battery production,” says Mendler. Lishen and Bühler have already agreed to further expand their collaboration.