Comprehensive Battery Safety Risk Evaluation: Aged Cells versus Fresh Cells Upon Mechanical Abusive Loadings

Abstract

Despite their wide applications, lithium‐ion batteries (LIBs) have been struggling with their safety risks arising from different lifetime stages. Here, the NCMA pouch cell is taken as an example, and the safety of both fresh and aged cells from three milestone stages, that is, internal short circuit (ISC) triggering risk, ISC mode, and the subsequent thermal runaway (TR) consequence is investigated. By combining mechanical abusive testing and physics‐based models on commercialized cells with various states‐of‐health (SOH) and states‐of‐charge, it is discovered that the ISC triggering delays with the decay of SOH and soft ISC mode will be triggered more frequently, which is mainly due to the mechanical behaviors of the current collectors. The temperature rises and peak temperature during the subsequent TR also become milder for aged cells due to the reduced capacity and deterministic soft ISC process. Results here provide a mechanistic explanation of the safety risk comparison between the fresh and aged cells, offering cornerstone guidance to the evaluation and design of next‐generation safer LIBs.

Advances and challenges in thermal runaway modeling of lithium-ion batteries

“…However, thermodynamic parameters obtained from calorimetry tests are specific to one chemical system or state, as TR performance is influenced by materials, 87 , 88 state of charge (SOC), 89 and state of health (SOH). 90 , 91 In practical applications, SOC and SOH may vary over time or between cells, including SOC changes during cycling and differing aging degrees due to cell inconsistency. Recently, some modeling strategies have been proposed to identify thermodynamic parameters across the full SOC range, such as interpolating kinetic parameters 92 and developing thermal-electric coupled models based on dimensionless normalized concentration.…”

Interaction between LMFP and NCMA and Its Effect on Blending Cathode-Based Cells

“…On the way to develop high-energy batteries, high-nickel layered-structure material is widely applied as a cathode for Li-ion cells [1][2][3]. However, its relative unstable structure raises concerns on safety issues [4][5][6][7]. Compared to conventional layered-structure cathodes, including LiNi 1−x−y Co x Mn y O 2 (NCM) and LiNi 1−x−y Co x Al y O 2 (NCA), LiNi 1−x−y−z Co x Mn y Al z O 2 (NCMA) shows more benefits for (a) low cost-Al was selected to partially substitute expensive Co element while maintain the material's high specific capacity; (b) extra cycling stability-NCM volume contraction/expansion during the H2 ↔ H3 phase transition is slightly reduced by Al doping; and (c) enhanced thermal stability-NCMA is structurally stable due to the synergetic effect of Al and Mn ions stabilizing the layered structure and delaying the thermally induced phase transitions [2,8].…”

A Hierarchical Modeling Framework for Electrochemical Behaviors in Lithium‐Ion Batteries with Detailed Structures

“…The accurate modeling of lithium‐ion batteries is pivotal in facilitating their broader application, ensuring cost‐effectiveness, optimal performance, safety, and durability as the next‐generation power sources and energy storage systems. [ 1–3 ]…”

“…The accurate modeling of lithium-ion batteries is pivotal in facilitating their broader application, ensuring cost-effectiveness, optimal performance, safety, and durability as the next-generation power sources and energy storage systems. [1][2][3] Recently, a range of models encompassing electrochemical, thermal, mechanical, and multiphysics aspects of LIBs have been established and applied across diverse scenarios. [4][5][6][7][8] Among these, physics-based and equivalent circuit models have emerged as two widely employed approaches for characterizing the electrochemical behavior of lithium-ion batteries.…”