Breakthrough in lithium-metal solid-state battery technology

Why solid-state batteries matter

As electric vehicle (EV) adoption continues to grow, so does the need for more powerful and efficient batteries. Consumers are increasingly looking for cars that offer longer driving ranges and faster charging times. However, traditional lithium-ion batteries have limitations, particularly when it comes to energy density and safety. They rely on liquid electrolytes, which can be prone to leaks and fires.

Solid-state batteries, on the other hand, replace the liquid electrolyte with a solid material, offering several benefits. These include higher energy density, better thermal stability, and a lower risk of fire. Yet, despite their potential, solid-state batteries have been difficult to produce in a cost-effective way—until now.

A significant boost in energy density

The prototype developed by imec and its partners has changed that. Their lithium-metal solid-state battery achieves a remarkable energy density of 1070 Wh/L. This was made possible by combining several advanced materials and innovative manufacturing techniques.

At the core of the design is a “liquid-to-solid” electrolyte, created using a polymerized ionic liquid (PIL) nanocomposite. This electrolyte solidifies at room temperature, simplifying the production process. Additionally, the battery uses a thin lithium metal anode and a 50 μm solid electrolyte separator, creating a compact and efficient cell structure. The result is a battery that can store more energy in less space, offering a significant improvement over current technologies.

Affordable and scalable production

One of the most exciting aspects of this new battery is its cost-effective manufacturing process. Imec and its partners designed the production method to be compatible with existing lithium-ion battery factories. This means companies won’t need to invest in entirely new facilities to produce these solid-state batteries.

The process is also projected to reduce costs to less than €150 per kilowatt-hour (kWh), which would make solid-state batteries an affordable option for electric vehicles. This is a crucial development because the cost of the battery pack remains one of the largest factors influencing the overall price of EVs.

Tackling safety and sustainability challenges

In addition to its energy and cost advantages, this new battery offers improved safety. Traditional lithium-ion batteries can be prone to overheating and fires due to the liquid electrolytes inside them. The solid-state design, with its more stable electrolyte, reduces these risks. By using materials that are less likely to ignite, the battery provides a safer option for vehicles and other applications.

Imec’s battery also addresses environmental concerns. The team used cobalt-lean NMC cathodes, which help lower the environmental impact of production while maintaining high capacity. Reducing reliance on cobalt is a priority for the industry, given the metal’s environmental and ethical sourcing issues.

Overcoming technical challenges

Developing a battery with such high performance wasn’t easy. The team faced several technical challenges along the way, particularly in making the solid electrolyte strong enough for practical use. To overcome these, they introduced advanced coatings and fine-tuned the materials used in the battery’s construction. These improvements not only enhanced the battery’s durability but also shortened its charge time to just three hours and extended its lifespan to 100 cycles.

Looking ahead

The successful development of this lithium-metal solid-state battery is just the beginning. Imec and its partners are now focusing on scaling up production to make these batteries available for industrial use. They’re also working on further improvements, such as increasing energy and power density and exploring next-generation materials for even better performance.

The consortium behind this breakthrough includes leading research institutions like Fraunhofer (Germany) and Delft University of Technology (Netherlands), as well as industry players like Fiat’s research center (Italy) and VDL Groep (The Netherlands). Their combined expertise will be critical in bringing this technology to market and ensuring it meets the needs of the growing EV industry.

Conclusion

Imec and its partners have made a significant leap forward in battery technology. By developing a lithium-metal solid-state battery with high energy density and a cost-effective manufacturing process, they’ve opened the door to more efficient and affordable electric vehicles. As the world continues to push for lower carbon emissions and more sustainable energy solutions, this breakthrough could play a vital role in shaping the future of transportation and energy storage.

With further testing and development, this technology could soon become a standard in the automotive industry, driving the next wave of innovation in clean energy.

Source: Imec