A research team at the Fraunhofer Institute for Manufacturing Engineering and Automation IPA is working on sustainable and cost-effective high-energy round cells for home storage systems that do not contain any toxic or carcinogenic materials. According to the institute, these cells will also have a higher energy density than conventional lithium iron phosphate battery cells.
This means that substances such as nickel and cobalt will not be used in the electrodes. »These materials require a lot of safety technology and complex protective measures in cell production,« says Johannes Wanner, business segment manager for battery systems at Fraunhofer IPA. »If they are eliminated, production will inevitably become cheaper.«
Wanner’s research team is therefore focusing on developing a fluorine-, cobalt- and nickel-free cathode, such as a lithium manganese iron phosphate (LMFP) cathode, and combining it with a high-capacity anode. To truly embrace the concept of a sustainable battery cell, the electrolyte and binder will also be free of fluorine, rendering the battery cell entirely fluorine-free. This also improves cell safety, as hydrogen fluoride can no longer be produced.
»In battery cell production, up to 30 per cent of material is wasted when changing to new electrode coils,« says Wanner. This is both a cost driver and an environmental problem. The research team aims to reduce waste by using a process known as delamination, whereby the defective coatings on the electrodes can subsequently be removed and replaced. Eliminating the standard fluorine-containing binder polyvinylidene fluoride (PVDF), a PFAS material, makes the materials easier to reuse in new cells, thereby improving the recycling rate.
In recent years, scientists at Fraunhofer IPA have set up a fully networked production line for cylindrical battery cells at the ZDB. They now intend to use it to develop their sustainable, high-energy round cell and increase its production capacity. Varta Microbattery, an associated partner, is supporting the project. The battery cell is expected to be ready for the market by the end of 2028.
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