Fast lithium growth and short circuit induced by localized-temperature hotspots in lithium batteries

Abstract

Fast-charging and high-energy-density batteries pose significant safety concerns due to high rates of heat generation. Understanding how localized high temperatures affect the battery is critical but remains challenging, mainly due to the difficulty of probing battery internal temperature with high spatial resolution. Here we introduce a method to induce and sense localized high temperature inside a lithium battery using micro-Raman spectroscopy. We discover that temperature hotspots can induce significant lithium metal growth as compared to the surrounding lower temperature area due to the locally enhanced surface exchange current density. More importantly, localized high temperature can be one of the factors to cause battery internal shorting, which further elevates the temperature and increases the risk of thermal runaway. This work provides important insights on the effects of heterogeneous temperatures within batteries and aids the development of safer batteries, thermal management schemes, and diagnostic tools.

3D microstructure design of lithium-ion battery electrodes assisted by X-ray nano-computed tomography and modelling

“…Heterogeneous pore phase and particle packing can result in high current densities locally, leading to a non-uniform state-of-lithiation (SoL) 11,14 and hot-spot formation 13,15 . Consequently, uneven utilisation of the active material as well as non-uniform mechanical (cracking and delamination) [16][17][18] and electrochemical (ionic mixing and phase transition) aging 19,20 significantly reduce the cell's cycle life, energy density and safety 21,22 , particularly under high-rate conditions 23,24 . Improved understanding of the interplay between microstructural heterogeneities and battery performance not only helps to alleviate degradation, but also provides new insights into advanced structure design.…”

Recent Advances of Emerging 2D MXene for Stable and Dendrite‐Free Metal Anodes

“…[89,90] Other Methods: In addition to the above-mentioned methods, other methods for stabilizing the alkali-metal anodes have also been proposed in the past several years. These methods include changing the deposition environment of alkali metal, [91][92][93][94] regulating the working current density, [95,96] modifying separators, [97][98][99][100] using multifunctional binders, [101] and utilizing new current collectors. [102]…”

Near-Zero-Energy Smart Battery Thermal Management Enabled by Sorption Energy Harvesting from Air

“… 8 Remarkably, LIBs face the safety risks of overheating and thermal runaway if they work under high temperatures for a long duration. 9 , 10 However, a low ambient temperature also threatens the working performance and safe operation of LIBs because the diffusion kinetics of Li + ions becomes slow and Li metal deposition occurs. 11 As a result, LIBs suffer from significant performance degradation in terms of both energy power and energy density, thus causing issues for EV applications in cold regions, especially during the start-up stage of EVs.…”