Summary
The guest lecture was organized by Dr. V. Srinivasadesikan, Associate Professor, Department of Chemistry, VFSTR. Dr. V. Srinivasadesikan introduced the guest speaker, Dr. Sreedhar Naidu, and read his profile.
Dr. Sreedhar Naidu, Dy. Manager, Amara Raja Batteries, Tirupathi, spoke about the lead-acid batteries and the current challenges in the industry. Lead-acid batteries remain a foundational energy storage technology for automotive applications despite increasing penetration of lithium-ion systems. Their proven reliability, intrinsic safety, robust cold cranking performance, mature supply chain, and exceptional recyclability make them indispensable for internal combustion engine (ICE) vehicles and hybrid electric vehicles (HEVs). In these platforms, lead-acid batteries primarily support starting, lighting, ignition (SLI), and low-voltage auxiliary loads, where high power delivery, predictable failure modes, and cost efficiency are essential. He also delivers and discusses the key topics of Key Active and Structural Materials, Electrolyte System and Separators, Additives and Material Optimization, Role in ICE and Hybrid Vehicles, 12V Low-Voltage Automotive Systems, and Sustainability and Recycling. He concluded with the ongoing advancements in grid alloys, separator technologies, and electrode additives that have enabled lead-acid batteries to meet the evolving requirements of modern automotive platforms. For low - voltage energy storage in internal combustion and hybrid vehicles, advanced lead‑acid battery materials remain a reliable, economical, and environmentally sustainable solution that will continue to complement electrified powertrain technologies. At the end of the session, all the faculty members, research scholars, and students raised a few questions, which were addressed by the speaker. Finally, the HoD, school dean, and faculty members congratulated the speaker for his scientific talk and discussion.
About Guest Lecture
Introduction
Lead-acid batteries remain a foundational energy storage technology for automotive applications despite increasing penetration of lithium-ion systems. Their proven reliability, intrinsic safety, robust cold cranking performance, mature supply chain, and exceptional recyclability make them indispensable for internal combustion engine (ICE) vehicles and hybrid electric vehicles (HEVs). In these platforms, lead-acid batteries primarily support starting, lighting, ignition (SLI), and low-voltage auxiliary loads, where high power delivery, predictable failure modes, and cost efficiency are essential.
Key Active and Structural Materials
Automotive lead-acid batteries employ lead dioxide (PbOâ‚‚) as the positive active material and spongy lead (Pb) as the negative active material. These active masses are supported on lead-based grid alloys that ensure mechanical integrity, electrical conductivity, and corrosion resistance. Modern automotive grids predominantly use lead-calcium (Pb-Ca) and lead-calcium-tin (Pb-Ca-Sn) alloys, replacing traditional lead-antimony systems to reduce water consumption, suppress corrosion, and improve charge acceptance under partial state of charge operation.
Electrolyte System and Separators
The electrolyte is a dilute sulfuric acid (Hâ‚‚SOâ‚„) solution that participates directly in electrochemical energy conversion. In advanced enhanced flooded batteries (EFBs) and absorbent glass mat (AGM) designs, electrolyte management is optimized to withstand dynamic automotive duty cycles. Microporous polyethylene separators are used in flooded and EFB batteries, while boron silicate glass microfiber separators are employed in AGM batteries to immobilize electrolyte, reduce internal resistance, and enhance vibration tolerance.
Additives and Material Optimization
Performance-enhancing additives have become increasingly important for modern automotive duty cycles. Carbon-based additives incorporated into the negative active material improve dynamic charge acceptance and mitigate sulfation under partial state of charge conditions. Organic expanders and barium-based compounds are used to preserve plate porosity, enhance cycle life, and stabilize long-term electrochemical performance.
Role in ICE and Hybrid Vehicles
In ICE vehicles, lead-acid batteries deliver high cold cranking current and support growing electrical loads associated with safety, infotainment, and body electronics. The adoption of start-stop systems has increased cycling demands, necessitating EFB and AGM constructions. In HEVs , lead-acid batteries serve as 12 V auxiliary power sources, ensuring ECU functionality, system wake-up, and fail-safe operation during high-voltage battery isolation events.
12 V Low Voltage Automotive Systems
The 12 V electrical system remains fundamental to ICE and hybrid vehicle architectures. AGM and EFB lead-acid batteries dominate this domain due to their high instantaneous power capability, superior cold temperature performance, predictable safety behavior, and low total cost of ownership. AGM batteries, in particular, exhibit enhanced cycling durability, low internal resistance, and extended partial state of charge tolerance required for modern start-stop and hybrid duty cycles.
Sustainability and Recycling
A defining advantage of lead-acid battery technology is its closed-loop materials ecosystem. More than 95% of lead-acid battery materials—including lead, plastic housings, and electrolyte - are recovered and reused. This near-perfect recyclability minimizes environmental impact, reduces dependence on primary raw materials, and supports a well-established circular economy model.
Conclusion
Ongoing advancements in grid alloys, separator technologies, and electrode additives have enabled lead-acid batteries to meet the evolving requirements of modern automotive platforms. For low-voltage energy storage in internal combustion and hybrid vehicles, advanced lead-acid battery materials remain a reliable, economical, and environmentally sustainable solution that will continue to complement electrified powertrain technologies.
