Effect of Vibrational Abuse on the Electrodes of Nickel Manganese Cobalt (NMC) and Lithium Iron Phosphate (LFP) 18650 Cells

<div class="section abstract"><div class="htmlview paragraph">In light of the growing demand for Electric vehicles (EVs) as a sustainable mode of transportation, it becomes essential to understand the effect of various abuse conditions that batteries undergo. Vibrational abuse is a significant condition experienced by batteries in operation. Vibrations caused by road roughness, acceleration inertia, and other factors can affect key performance indicators such as cycle life, capacity retention, and safety. These cells undergo various chemical and mechanical reactions over time, leading to the degradation of components like the anode, cathode, electrolyte, separator, and current collector, resulting in reduced performance. Therefore, understanding battery degradation is important for managing system performance. This study is focused on a detailed analysis of Lithium Iron Phosphate (LFP) and Nickel Manganese Cobalt (NMC) cells subjected to vibrational abuse. Vibration testing was carried as per International Electrotechnical Commission (IEC) standard 62660-2 to assess the effect on cylindrical 18650 NMC & LFP cell materials. The cells were tested at different state of charge (SoC) levels-75% and 100%- under vibrational conditions. Testing parameters included an 8-hour duration in all directions (x, y, z), a frequency range of 10-2000, and an acceleration of 3 g- rms. post-testing, internal resistance was measured, and both anode-cathode materials underwent visual examination and detailed electrode material analysis using a scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). The study indicated that vibrational abuse significantly affected NMC battery cells, which showed electrode degradation to a greater extent than LFP cells.</div></div>