5 times faster: New process accelerates battery cell production

High-speed stacking SVOLT Energy Technology

One goal in battery development is to maximise the number of battery cells in the battery pack of an electric car. But SVOLT's high-speed stacking is about more than that: the process has many significant advantages.

2024/03/14 - It was an April Fool's joke in spring 2016 when the fast food chain BURGER KING® presented its new "Square" product line on social media. The first square Whopper® was supposed to require 25 percent less transport costs and up to 32 percent less storage space thanks to more efficient use of space. And all this without changing the portion size.

It was no joke when a large coffee retail chain announced at the beginning of 2023 that it would be using a square shape for its capsules in future. The compact "cubes" could be better stacked and packaged in a more space-saving way.

What has this got to do with traction batteries?

With batteries for electric cars it's also about fitting as many battery cells as possible into as little space as possible. And just as round coffee capsules do not stack well, the same applies to round battery cells. In contrast, rectangular, prismatic cells, such as those offered by battery manufacturers like SVOLT, can be stacked particularly well and are superior to round, wound battery cells in terms of space utilisation.

Production boost for battery cells

Until now, the stacking process - in which eight electrode sheets are folded for prismatic cells - was slower than the conventional winding of round cells. Prismatic cells were therefore considered too expensive for upscaling electric cars. However, the "High Speed Stacking" developed by SVOLT speeds up the previous process by a factor of eight. The new process also saves 30 percent of the space within a battery cell factory that was previously used for stacking.

The reason: round cells require more space for the winding technology, in which the electrodes are wrapped around a core. This process is less space-efficient and requires more production space. When manufacturing prismatic cells, the production equipment can be closer together, as the feeding and handling of the materials requires less space than the movement and processing of round cells. The bottom line is that high-speed stacking reduces energy costs: the air on the surface where stacking or winding takes place has to be dried in a costly and energy-intensive process to ensure the necessary process reliability.

Following a trial phase and a pilot project, SVOLT has been using high-speed stacking in series production since May 2023.

Prismatic cells therefore not only deliver more energy in a given installation space: thanks to high-speed stacking, they can now also be produced considerably faster - with significantly reduced space requirements in production.