TUM Innovates Electrolyte for High-Conductivity Solid-State Batteries

Solid-state batteries are increasingly viewed as the future of energy storage, thanks to their potential to enhance performance in various applications, particularly in electric vehicles. Researchers at the Technical University of Munich (TUM) have made significant strides in this field by developing a new electrolyte that markedly improves the efficiency of these batteries.

The research team, led by chemist Thomas Fässler, has created an electrolyte capable of conducting lithium ions more rapidly than any previously known materials. This innovative substance is composed of lithium, antimony, and scandium. Traditionally, solid-state electrolytes have relied on lithium-sulfur compounds, which often require complex modifications involving up to five additional elements to optimize performance.

One of the key advancements in this new electrolyte is the alteration of its crystal lattice structure. The researchers replaced every three lithium atoms with a single scandium atom, a transition metal that belongs to the rare earth elements category. This modification generates vacancies within the lattice, facilitating a more efficient and rapid movement of lithium ions.

According to the findings published in the journal Advanced Energy Materials, this novel electrolyte exhibits a conductivity that is over 30% superior to that of existing materials. To validate these results, the team collaborated with colleagues from the Chair of Technical Electrochemistry at TUM.

Jingwen Jiang, the lead author of the study, remarked that the combination of lithium and antimony could potentially be adapted for use with lithium-phosphor systems as well. The team is optimistic that their discovery could have broader implications for enhancing conductivity in various other materials.

Fässler emphasized the importance of this breakthrough in fundamental research, suggesting that the introduction of small amounts of scandium may indicate a new principle that could influence future combinations of elements. Notably, this material is not limited to ion conduction; it also has the potential to conduct electrons, making it a candidate for integration into electrodes.

However, Fässler cautioned that extensive testing is still required before this innovation can be applied in battery cells. The research team has already filed for a patent on their development, signaling the significance of their work in the field.

Solid-state batteries not only promise a higher energy density but also enable faster charging compared to conventional lithium-ion batteries. Additionally, they offer enhanced safety as they are less prone to combustion. Despite these advantages, solid-state batteries remain more expensive than traditional lithium-ion options, which poses a challenge for widespread adoption.