Impact of ball milling on the energy storage properties of LiFePO4 cathodes for lithium-ion batteries

Particle size reduction through ball milling presents an appealing approach to enhance the energy storage properties of lithium iron phosphate used in cathodes for lithium-ion batteries. However, the impact of ball milling conditions on electronic conduction and specific storage capacities remains poorly understood. In this study, we investigated the effects of both dry and solvent-based ball milling (utilizing water, methanol, and acetone) on microstructural, electronic, and electrochemical properties. The use of water and methanol resulted in particle agglomeration, creating additional paths for electronic conduction but adversely affecting specific energy storage capacity. Conversely, the utilization of acetone reduced the formation of these agglomerates, improving electronic conduction. However, this also led to the creation of defects that hindered an enhancement in energy storage. Ultimately, dry milling emerged as the optimal method under the experimental conditions assessed here. It achieved a more significant reduction in particle size, an increase in electronic conduction, and a higher specific energy storage capacity.