Surface coatings to mitigate phase separation in LiFePO4 during lithium-ion battery discharge
Artikel i vetenskaplig tidskrift, 2026
To achieve long-lasting, high-performance lithium-ion batteries, local inhomogeneity in current density must be avoided. One driver of such inhomogeneity is the spinodal decomposition of active materials into Li-rich and Li-poor phases during charge and discharge, respectively. Whether or not such phase separation occurs is linked to the dynamics of lithium (Li) at the active material surface and within its bulk. Here, we show that particle surface coatings can be designed to inhibit phase separation. Using LiFePO4 as a model system, we prepare particles with different coatings in order to tune Li dynamics and electronic structure and thereby induce or prevent phase separation, which we verify through experiment and ab initio calculations. We then leverage our findings to create a mixed ceramic-carbon coating that mitigates phase separation down to rates as low as 0.1C and simultaneously enables fast (dis)charge up to 5C.
lithium-ion batteries
phase separation
surface coating
spinodal decomposition
LiFePO4
lithium dynamics
Författare
Peter Benedek
Eidgenössische Technische Hochschule Zürich (ETH)
Stanford University
Xueyan Zhao
Eidgenössische Technische Hochschule Zürich (ETH)
Emanuel Rudolf Bileter
Eidgenössische Materialprüfungs- und Forschungsanstalt (Empa)
Annina Moser
Eidgenössische Technische Hochschule Zürich (ETH)
Ola Kenji Forslund
Kungliga Tekniska Högskolan (KTH)
Nami Matsubara
Kungliga Tekniska Högskolan (KTH)
E. Nocerino
Kungliga Tekniska Högskolan (KTH)
Stephen P. Cottrell
STFC Rutherford Appleton Laboratory
Marisa Medarde
Paul Scherrer Institut
Yasmine Sassa
Chalmers, Fysik, Materialfysik
Ramesh Shunmugasundaram
Eidgenössische Technische Hochschule Zürich (ETH)
Thomas Francisco Jaramillo
Stanford Engineering
Stanford University
A. Borgschulte
Eidgenössische Materialprüfungs- und Forschungsanstalt (Empa)
Fanni Jurànyi
Laboratory for Neutron Scattering, Villigen
Martin Månsson
Kungliga Tekniska Högskolan (KTH)
Vanessa Wood
Eidgenössische Technische Hochschule Zürich (ETH)
Matter
25902393 (ISSN) 25902385 (eISSN)
Vol. In PressÄmneskategorier (SSIF 2025)
Materialkemi
Den kondenserade materiens fysik
Fysikalisk kemi
DOI
10.1016/j.matt.2026.102725