KAIST researchers used a 3D digital twin to map battery degradation, revealing how electrode structure affects performance during rapid charging while guiding longer-lasting battery design.
Researchers at the Korea Advanced Institute of Science and Technology (KAIST) have developed a 3D digital twin that identifies why electric vehicle batteries degrade during fast charging. The virtual model recreates the internal structure of a graphite anode, allowing researchers to examine microscopic processes that are difficult to observe experimentally.
The study found that the spatial arrangement of materials inside an electrode can strongly influence battery performance, even when batteries have similar overall charge capacities. In particular, the distribution of binder materials and pore spaces affects lithium-ion movement and the formation of protective layers inside the electrode.
Fast charging can cause several degradation mechanisms within graphite anodes. Lithium ions must move rapidly through electrolyte-filled pores and into graphite particles. When charging conditions become more demanding, uneven material arrangements can restrict these pathways and contribute to performance losses.
The researchers used a 3D digital twin based on an actual commercial graphite anode to simulate these internal processes. The model reconstructs the three-dimensional arrangement of graphite particles, binder and electrolyte pores, enabling the team to track lithium-ion movement, lithium plating and structural stress.
The simulations showed that anodes with almost identical overall capacities can experience substantially different internal degradation depending on their microstructure. In a 50-micrometre-thick anode, concentrating binder near the separator increased performance-degrading lithium plating compared with a more evenly distributed arrangement.
The study also found that distributing binder more uniformly can create consistent lithium-ion transport pathways and protective-film formation. In thicker, 80-micrometre anodes, strategically positioning binder increased charge capacity compared with uneven distributions.
The researchers say the findings could help manufacturers design faster-charging EV batteries with longer lifespans. By testing electrode layouts virtually before producing physical prototypes, the digital-twin approach could reduce trial and error and improve battery design.
