Fraunhofer Institute Achieves Over 1000 Cycles and 280 Wh/kg with Silicon-Anode Batteries

Breakthroughs in High-Energy Battery Testing

According to НВ — Техно: The Fraunhofer Institute for Solar Energy Systems has revealed promising test results for high-capacity batteries featuring silicon-based anodes, developed under the StrOboBatt project. Designed for electric vehicles, aviation, and stationary storage, these batteries demonstrated exceptional durability by completing more than 1000 charge-discharge cycles while maintaining an energy density of up to 280 Wh/kg. Industrial-scale production is expected to push this value even higher, reaching approximately 330 Wh/kg.

Technical Insights and Performance Data

Tests were conducted on 25 Ah battery cells under axial pressures of 300 and 1000 kPa with a 1C current rate. The anodes combine graphite with a silicon-carbon composite, making up 51% of the active material, while the cathodes consist of nickel, manganese, and cobalt oxides with a high nickel content. Applying axial pressure significantly reduces interfacial resistance and minimizes electrode delamination risks. At 1000 kPa, the batteries retained over 83% of their initial capacity after 1000 cycles, whereas at 300 kPa, capacity degradation was more noticeable.

Lucas Dold from Fraunhofer emphasized,

“Battery lifespan remains a major challenge for the widespread industrial use of high-silicon anodes. Achieving over 1000 cycles with at least 80% capacity retention is a critical milestone.”

Mark Kissling highlighted the role of axial pressure, stating,

“Under a contact pressure of 1000 kPa, our cells maintain over 83% of their original capacity even after more than 1000 full cycles.”

These advancements represent a significant step forward in energy-dense battery technology, with the potential to transform electric transportation and other cutting-edge industries.

Integrating these innovations into battery manufacturing is key to enhancing both efficiency and longevity of storage systems. This progress supports reducing reliance on conventional energy sources and promotes the growth of environmentally friendly transportation solutions. Ongoing research is expected to further increase energy density and battery lifespan-essential factors for meeting the demands of today’s industrial applications.

In addition to advancements in silicon-anode technology, researchers are also exploring innovative materials to enhance battery performance. For instance, composite materials developed for zinc-air batteries show promise in improving efficiency and lifespan, highlighting the broader efforts within the industry to create more sustainable energy solutions.