Optimised EV fast charging: fourfold increase in battery life

In recent years, fast charging for electric vehicle applications has been a topic of immense importance among battery researchers. This arises from the need to address people’s anxiety of EV driving range while ensuring good performance and safety of lithium-ion batteries. However, fast charging involves a high current, which increases the cell temperature and ultimately leads to capacity loss of the battery.  

Under fast charge conditions when high temperatures are reached, compounds are leached from the cathode, contributing to capacity decrease. An understanding of the leaching mechanism under practical operating conditions is important for designing the safe fast charging test method. 

This presentation will discuss the plausible reaction mechanism for the leaching process. Several new observations, such as the extent of deposition at the electrodes and catalyzed solid-electrolyte interface formation, provide key insights needed to understand capacity decrease during fast charging. An optimised fast-charging test method has mitigated leaching, resulting in battery life extension by four times compared with the conventional fast charging method. Such findings will provide significant new insights into the understanding and control of capacity decrease due to transition metal ion dissolution for advanced fast-charging battery systems. 

Format:

• 5 min welcome and introduction
• 30 min presentation 
• 15 min facilitated Q&A by Thrinath Ramireddy, Postdoctoral Fellow, Battery Storage and Grid Integration Program 

About the speaker

Vallabha Rao Rikka is a postdoc researcher at the Electrochemical Safety Research Institute (ESRI), Underwriters Laboratories, USA, where he works on the safe fast charging of lithium-ion batteries and beyond lithium-ion batteries for electric vehicle applications.

Vallabha was a scientist at ARCI Chennai’s Centre for Advanced Energy Materials (CAEM). Focused on cell formation and life cycle studies at fast charging of cylindrical and prismatic lithium-ion cells of made in-house for use in electric vehicles and energy storage applications. Vallabha is skilled at in-situ/ex-situ operando characterisation of electrode and electrolyte interfaces.

During the course of the past nine years, Vallabha’s primary focus has been on the development of test methods for the rapid and effective formation of a solid electrolyte interphase (SEI) layer on the anode surface of a lithium-ion battery (LIB).  This invention reduces lithium-ion cell formation time by 75% compared to the conventional process and has an Indian patent (Indian Patent, Patent application No. 202011052906). He has derived the fast-charging test protocol, which is one of the safest charging test methods for electric vehicle applications and can charge a battery to 100% of its capacity in just 15 minutes. This protocol eases range anxiety.