Improving Performance in Electric Vehicle Batteries  

CBI spoke to Marcus Young, an Associate Professor and Associate Department Chair for the Undergraduate Program at the University of North Texas (UNT) about a two-year project that kicked off in February 2023 to look at materials in low voltage (12V) batteries for electric vehicles in an effort to further improve performance of lead batteries.  

Lead batteries are still used in virtually every car on the road-from combustion engine vehicles through to Electric vehicles. Working alongside UNT, East Penn Manufacturing Company, and ECOBAT, CBI will further study the 12V battery electrochemical processes for materials and duty cycles common for lead batteries used in electric vehicles. By understanding more of how these batteries function in different charge conditions, temperature, and climate, we can determine what changes will attain a longer life span and better performance. 

Electric vehicles rely on lead batteries to provide safety functionality in the case of failure of the main propulsion battery.  This application is referred to as low voltage or auxiliary battery functionality. The lead batteries used in low-voltage EV applications use advanced alloys with different metallic additives to achieve current levels of performance. The study will focus on two specific additives, Ba (barium) and Bi (bismuth), and how their grain structure and influences on corrosion rates and crystallization would affect grid performance in the conditions found in EVs Previous research has shown that grids with Ba additives have reduced oxide formation, while Bi facilitates faster recrystallization. 

Using XRM – or X-ray microscopy, this project will investigate corrosion in batteries and look at the impact of Ba or Bi additives on battery life. The technique requires relatively thin samples to be used.  Extremely thin pieces have been created and used on the nano scale, so that they can be x-rayed. As the x-ray penetrates through these panels, researchers will isolate areas of interest and study the impact of aging time to see a source(s) of potential problems. 

Beyond lab-scale techniques, synchrotron experiments at the APS at Argonne National Laboratory will be used on large samples linking lab findings to real world lead battery products used in auxiliary applications.   

“We’re making battery life better for everyone,” said Young. He explained that ultimately this research will impact daily users as the battery storage community creates faster, better, and more efficient sources.