Elucidating the Origin of Intensified Thermal Safety Concerns of Practical Next‐Generation High‐Energy‐Density Li‐Ion Batteries
Abstract
ABSTRACT High‐specific‐energy battery systems, crucial for powering heavy‐lift unmanned aerial vehicles (UAVs) and electric vertical take‐off and landing (eVTOL) aircraft, are regarded as key enablers for the development of the low‐altitude economy. However, their commercialization remains hindered by significant thermal safety concerns. In this work, using an ultrahigh Ni‐rich layered oxide cathode (Ni accounts for 96%) paired with a mixed Si@C anode as a model system, we systematically investigate real‐time gas evolution behavior and elucidate the underlying mechanisms of gas generation at both cathode/anode electrodes, along with their crosstalk reactions during thermal runaway. The results reveal severe gas emission from the Si@C anode, with H 2 constituting 71.12% (mass ratio) of the total gas released. Meanwhile, the Ni96 cathode releases active oxygen species (O n− /O 2 ) at elevated temperatures (e.g., 220°C), which react with reducing gases generated from the Si@C anode and electrolyte, thereby triggering the onset of thermal runaway. Furthermore, a specially tailored low‐hydrogen (low‐H) electrolyte is employed to effectively suppress H 2 evolution, thereby enhancing the safety of high specific energy battery systems. These insights into gas evolution mechanisms provide a foundation for the targeted design of battery materials and the formulation of practical safety strategies for the low‐altitude sector.
Article Details
Authors (15)
Wenbin Tu
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Jinzhi Wang
Haitang Zhang
Wei Li
Junhao Wang
Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry and Molecular Engineering
Jiyuan Xue
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Yuan Tian
Yizhen Huang
Yuhang Wu
Yawen Yan
State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China
Yizhe Chen
Department of Chemistry
Yeguo Zou
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Department of Chemistry, College of Chemistry and Chemical Engineering
Xin Sun
Yu Qiao
Shi‐Gang Sun
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China