Refurbishing sulfated lead-acid batteries through surface electrochemical techniques

Lead-acid batteries (LABs) are the oldest rechargeable batteries, having a history of more than 150 years. Their immense popularity results from their simple chemistry, the ability to provide large currents, geographical abundance, and tolerance to abusive operations. This thesis aims to investigate and solve some of the long-standing issues associated with the technology of LABs- like their highly pollutive recycling process and propensity for self-discharging and gas evolution. A series of materials science and electrochemistry experiments were performed to locally study the failure of LABs due to sulfation and identify promising in-situ chemical refurbishing agents to recover the capacity loss for an increased cradle-to-gate lifetime and decreased environmental overheads. First, a surface electrochemical technique was developed to locally induce and study the sulfation behavior on model Pb anodes and characterize the renewal of electron transfer behavior upon chemical refurbishment. The method was tested using EDTA as a known agent for chemical refurbishment. Taking the work into commercial sulfated LAB anodes, two approaches were used- ionic liquids and organic anions. In the first, two amino-acid based ionic liquids were identified and one of them, [Ch][Ser], was employed to give a 75% capacity recovery from sulfated LAB anodes with <1% capacity remaining. In the second, the organic anion was employed to give a 99% capacity recovery from LAB anodes with similar levels of sulfation. As proof-of-concept, 35% capacity recovery was achieved from full commercial batteries after accelerated sulfation with 0.1% of the discharge capacity remaining. The deleterious effects of oxygen in accelerating self-discharge in LAB anodes were identified in the next study with the identification of increased production of Reactive Oxygen Species (ROS) which worsens corrosion and degradation of battery components in the presence of oxygen. A few directions for future work are also outlined in the final chapter, along with an ongoing work on rapidly estimating complexation strengths from small solution volumes.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Materials Science & Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Baby, Aravind

Contributors dc:contributor

• Rodríguez-López, Joaquín
• Shoemaker, Daniel
• Perry, Nicola H
• Zhang, Yingjie

• Lead-acid Battery
• Refurbishment

Statement dc:rights

• © 2024 Aravind Baby

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/125789

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F125789