Dry bulk processing methods can offer surprising control of particle shape, size, internal composition, and surface morphology. Mechanofusion is a method that can be used to smooth, spheronize, coat, and embed particles [1–4]. Dry particle microgranulation (DPMG) is a newly developed mechanofusion method in which ~50 μm speres are added to the process as "templating" media [5]. Here it will be shown that DPMG and new applications of mechanofusion offer unprecedented control in particle shape, internal porosity, and internal composition variation, enabling the creation of never before possible highly engineered particles, including:

• consolidating submicron particles into dense and uniform ~10 μm particles that are spherical or tetrahedral in shape
• spontaneous formation of core/shell particles from a mixture of submicron particles with different compositions
• creating spherical graphite particles from fine flake graphite
• embedding nanoparticles within the core of ~10 μm host particles
• applying fused dense oxide particle coatings
• smoothing the surface of polycrystalline particles to lower their surface area

Such methods can produce no waste and operate at 100 % yields, greatly reducing environmental impact and cost compared to other commercial particle production methods. This offers tremendous opportunity for creating sustainable advanced battery materials. Examples of new cathode and anode materials synthesized by these methods and opportunities for new materials will be discussed.

References

[1] L. Zheng, T.D. Hatchard, M.N. Obrovac, A high-quality mechanofusion coating for enhancing lithium-ion battery cathode material performance, MRS Commun. 9 (2019) 245–250. doi:10.1557/mrc.2018.209.

[2] Y. Cao, T.D. Hatchard, R.A. Dunlap, M.N. Obrovac, Mechanofusion-derived Si-alloy/graphite composite electrode materials for Li-ion batteries, J. Mater. Chem. A. 7 (2019) 8335–8343. doi:10.1039/C9TA00132H.

[3] L. Zheng, C. Wei, M.D.L. Garayt, J. MacInnis, M.N. Obrovac, Spherically Smooth Cathode Particles by Mechanofusion Processing, J. Electrochem. Soc. 166 (2019) A2924–A2927. doi:10.1149/2.0681913jes.

[4] Y. Liu, M. Charlton, J. Wang, J.C. Bennett, M.N. Obrovac, Si 85 Fe 15 O x Alloy Anode Materials with High Thermal Stability for Lithium Ion Batteries, J. Electrochem. Soc. 168 (2021) 110521. doi:10.1149/1945-7111/ac3163.

[5] M.N. Obrovac, L. Zheng, M.D.L. Garayt, Engineered Particle Synthesis by Dry Particle Microgranulation, Cell Reports Phys. Sci. 1 (2020) 100063. doi:10.1016/j.xcrp.2020.100063.