Smart nano-scavengers improve the performance of lithium-ion batteries

The results of the research published on Advanced Functional Materials

The stability over time and safety of lithium-ion batteries are limited by chemical and electrochemical processes catalyzed by the presence, even in small quantities, of water molecules inside the cell itself. In particular, water reacts with fluorine-containing lithium salts, commonly used in commercial batteries, producing hydrofluoric acid which, in turn, attacks the cathode materials resulting in the release of transition metal ions (Co, Mn, Ni).
To eliminate, or at least reduce, these inconveniences, modern technological research focuses on nanomaterials capable of "capturing" pollutant molecules, thus reducing the level of damage to the electrochemical cell. This approach, which simulates typical behaviors of biological systems, is commonly defined as "self-healing".
In the article “Chitosan-Decorated Alumina Hybrid Nanoparticles as Smart Scavengers of HF and Dissolved Transition Metals in Lithium-Ion Batteries”, doi: 10.1002/adfm.202406315, published in the journal Advanced Functional Materials (Wiley, Impact Factor 19, 2022 Journal Impact Factor, Journal Citation Reports (Clarivate Analytics, 2023)), Prof. Piercarlo Mustarelli of the department of Materials Science of the University of Milano-Bicocca, in collaboration with the University of Pavia (Prof. Eliana Quartarone), proposes an innovative scavenger consisting of alumina nanoparticles functionalized with chitosan, able to activate autonomously in the presence of hydrofluoric acid and to capture transition metal ions, thus limiting the battery degradation processes.