The sensitive detection of the early-stage internal short circuit triggered by lithium plating through the simplified electrochemical model at various working conditions

Abstract

The internal short circuit (ISC) is one of the main causes of thermal runaway in batteries. Facing the current fast charging scenario of batteries, this paper aims to explore the sensitivity of solid-phase diffusion coefficient to ISC during high current charging. The voltage and current data of the real ISC is input into the simplified pseudo-two-dimensions model to identify the intrinsic parameters. The results indicate that the positive solid-phase diffusion coefficient (Ds,p) has higher sensitivity and stability than the negative solid-phase diffusion coefficient (Ds,n). For real ISC, the sensitivity of the solid-state diffusion coefficient increases as the charging current increases. This is consistent with the trends in ISC that we have derived from our low-temperature ISC extension experiment. For #1 ISC battery at 25 °C (SOC = 0.3–0.85), Ds,p changes by 56 % (3C) and 96 % (5C), and Ds,n changes by 6.87 × 10−14m2/s (166 %) (3C), 8.38 × 10−14m2/s (670 %) (5C). Moreover, the sensitivity of the solid-state diffusion coefficient to ISC decreases after battery aging, but it still has sufficient ability to diagnose ISC. High temperature will reduce the sensitivity of the solid phase diffusion coefficient.