Response Analysis of Li-Ion Battery Capacity Under the Influence of Vehicular Excitations

Li-ion batteries have become a more significant form of energy storage in portable applications in recent years, such as electric cars for on-road use and electric machinery for off-road use, where consistent and random vibrations occur. The mechanical design and internal component securing of a battery cell dictate its resilience to vibration and stress. A primary challenge in developing battery packaging for electric vehicles is the deformation of components caused by vibrations from the irregular road profile. Hence, it is essential to understand the influence of mechanical vibrations on the electric capability of Li-ion batteries. This work aims to investigate the effect of mechanical excitations on lithium-ion batteries. A vibration test is conducted in accordance with the SAE J-2380 standard to ascertain the cell’s charge and discharge capacity in a single cycle. The SAE J2380 vibration spectra are significant as they were structured to replicate 100,000 miles of vehicular operation and generated from variable street-collected data. The discharge curve is plotted revealing the status of voltage and current after the test and before the test. The results indicate that the cell’s capacity has decreased relative to its condition prior to the vibration test, implying a possible reduction in the cell’s electrical performance. Cellular degeneration occurred, leading to a loss in efficiency. Following the post-test, the leakage current decreased, suggesting that the internal resistance had increased. Consequently, the significant rise in DC resistance may be attributed to vibrations linked to a reduction in capacity.