Exploring battery material failure mechanisms through synchrotron X-ray characterization techniques

Rechargeable battery cycling performance and related safety have been persistent concerns.It is crucial to decipher the capacity fading induced by electrode material failure via a range of techniques.Among these,synchrotron-based X-ray techniques with high flux and brightness play a key role in understanding degradation mechanisms.In this comprehensive review,we summarize recent advancements in degra-dation modes and mechanisms that were revealed by synchrotron X-ray methodologies.Subsequently,an overview of X-ray absorption spectroscopy and X-ray scattering techniques is introduced for charac-terizing failure phenomena at local coordination atomic environment and long-range order crystal struc-ture scale,respectively.At last,we envision the future of exploring material failure mechanism.

Failure Prediction Modeling of Lithium Ion Battery toward Distributed Parameter Estimation

Lithium ion battery has typical character of distributed parameter system, and can be described precisely by partial differential equations and multi-physics theory because lithium ion battery is a complicated electrochemical energy storage system. A novel failure prediction modeling method of lithium ion battery based on distributed parameter estimation and single particle model is proposed in this work. Lithium ion concentration in the anode of lithium ion battery is an unmeasurable distributed variable. Failure prediction system can estimate lithium ion concentration online, track the failure residual which is the difference between the estimated value and the ideal value. The precaution signal will be triggered when the failure residual is beyond the predefined failure precaution threshold, and the failure countdown prediction module will be activated. The remaining time of the severe failure threshold can be estimated by the failure countdown prediction module according to the changing rate of the failure residual. A simulation example verifies that lithium ion concentration in the anode of lithium ion battery can be estimated exactly and effectively by the failure prediction model. The precaution signal can be triggered reliably, and the remaining time of the severe failure can be forecasted accurately by the failure countdown prediction module.

Overcharge to Remove Cathode Passivation Layer for Reviving Failed Li–O_(2)Batteries

Prolonging the lifetime of batteries is a long-term pursuit,and it is also one of the prerequisites for the practical application of batteries.However,this endeavor is challenging for high-energy Li–O_(2)batteries due to their poor charge efficiency and cathode passivation-induced by-products accumulation.Here,we demonstrated that overcharging Li–O_(2)batteries could facilitate the decomposition of accumulated residue products and revive the cathode;thus,the battery lifespan could be significantly extended.This long battery lifetime not only made full use of the Li anode but also enabled the battery to recycle in a safer way without the risk of firing and explosion.Furthermore,overcharge could be used in Li–O_(2)batteries with high mass loading,high rate,and large capacity.This overcharge strategy simplified the cathode regenerating procedures and realized system-level efficient use of battery components,thereby prolonging the life of Li–O_(2)batteries to meet the requirements of practical applications.