Analysis of Capacity Decay, Impedance, and Heat Generation of Lithium-ion Batteries Experiencing Multiple Simultaneous Abuse Conditions

Abstract

Abuse of Lithium-ion batteries, both physical and electrochemical, can lead to significantly reduced operational capabilities. In some instances, abuse can cause catastrophic failure, including thermal runaway, combustion, and explosion. Many different test standards that include abuse conditions have been developed, but these generally consider only one condition at a time and only provide go/no-go criteria. In this work, different types of cell abuse are implemented concurrently to determine the extent to which simultaneous abuse conditions aggravate cell degradation and failure. Vibrational loading is chosen to be the consistent type of physical abuse, and the first group of cells is cycled at different vibrational frequencies. The next group of cells is cycled at the same frequencies, with multiple charge pulses occurring during each discharge. The final group of cells is cycled at the same frequencies, with a partial nail puncture occurring near the beginning of cycling. The results show that abusing cells with vibrational loading or vibrational loading with current pulses does not cause a significant decrease in operational capabilities while abusing cells with vibrational loading and a nail puncture drastically reduces operational capabilities. The cells with vibration only experience an increase in internal resistance by a factor of 1.09-1.26, the cells with vibration and current pulses experience an increase in internal resistance by a factor of 1.16-1.23, and all cells from each group reach their rated lifetime of 500 cycles without reaching their end-of-life capacity. However, the cells with vibration and nail puncture experience an increase in internal resistance by a factor of 6.83-22.1, and each cell reaches its end-of-life capacity within 50 cycles. Overall, the results show that testing multiple abuse conditions simultaneously provides a better representation of the extreme limitations of cell operation and should be considered for inclusion in reference test standards.