What will the future hold for lead-acid batteries?

Lead-Acid Batteries in Energy Storage Applications

The core value of lead-acid batteries lies not only in their continued use as a mature product but also in the profound technical principles, engineering expertise, and deep understanding of energy storage system needs accumulated during their development. These invaluable experiences can be inherited, borrowed, and applied to broader fields in new energy and modern industrial scenarios, even providing insights for the future direction of energy storage technologies. In today's rapidly advancing renewable energy landscape, dominated by wind and solar power, the importance of energy storage systems has become increasingly prominent.

These systems are essential for addressing the intermittency and variability of renewables, serving as the cornerstone for building stable, efficient, and flexible smart grids. In this emerging arena, which demands high technical performance and cost-effectiveness, lead-acid batteries continue to play an indispensable role through their unique advantages, complementing other storage technologies effectively. For GW-scale wind-solar storage power stations, while lithium-ion batteries are favored for their high energy density and long cycle life, advanced lead-acid variants like lead-carbon batteries remain a key option in scenarios prioritizing ultimate cost benefits. Their lower initial investment, mature recycling systems, and higher safety (resistant to thermal runaway) make them ideal where energy density is not critical but reliability and economy are paramount.

For instance, they can handle grid peak shaving and valley filling, frequency regulation (especially lead-carbon batteries with fast response times), and backup capacity. In developing countries or cost-sensitive projects, lead-acid storage systems excel with their "affordable and manageable" characteristics, maintaining strong competitiveness.

To leverage strengths and mitigate weaknesses, hybrid schemes combining "lead-acid + lithium-ion + supercapacitors" are gaining attention. In such systems, lead-acid batteries (particularly long-life lead-carbon types) use their cost advantages and deep-cycle performance for long-duration, high-capacity energy storage and release ("energy-type" applications for base-load regulation and extended backup). Lithium-ion batteries handle mid- to short-term energy turnover with their high density and rate capability, while supercapacitors address short, high-frequency power surges (smoothing fluctuations and providing instant support) through ultra-high power density and extended cycle life. This "division of labor and collaborative operation" optimizes overall system performance, lifespan, and costs.

Lead-Acid Batteries in Electric Vehicle Applications

Beyond renewable energy generation, lead-acid batteries find applications in electric vehicles. Although they have been fully replaced by lithium-ion batteries in mainstream passenger EVs due to insufficient energy density, they retain niches in specific new energy transport segments or as auxiliary systems.

For example, in China and Southeast Asia, the market for low-speed EVs like electric tricycles, quadricycles, and patrol vehicles for short commutes or logistics is vast. These vehicles prioritize cost over range, making lead-acid batteries (deep-cycle or partial lead-carbon types) the dominant choice with their ultra-low procurement costs and mature supply chains.

Additionally, as mentioned earlier, automotive 12V auxiliary power systems persist. Even in advanced pure EVs (e.g., Tesla) and hybrids, the 12V low-voltage systems for controls, lights, wipers, and infotainment commonly use lead-acid batteries. This stems from their superior low-temperature cranking performance, cost, safety, and reliability compared to down-converting high-voltage lithium or small lithium auxiliaries.

In specialized vehicles and machinery electrification—where energy density is secondary but adaptability to harsh environments (vibration, dust, temperature swings), cost, and maintenance ease are key, such as explosion-proof mining vehicles or port AGVs—rugged traction-type lead-acid batteries still hold ground.

The Inspirational Value of Lead-Acid Batteries

Lead-acid batteries not only apply directly in storage but their century-long technical principles and engineering experiences offer significant inspiration for other storage technologies, especially electrochemical ones.

The active materials in lead-acid plates (spongy lead, lead dioxide) feature typical porous structures, where pore size distribution, surface area, and porosity are crucial. Techniques like porogens, particle morphology control, and volume change management (additives, grid design) in lead-acid batteries inspire electrode design in lithium-ion, sodium-ion, and flow batteries.

Maintaining ion and electron transport channels under high active material loads is a shared challenge across electrochemical systems. Similarly, research on electrolyte concentration, additives, and separators (e.g., AGM's liquid absorption and ion conduction) informs optimization in other batteries, enhancing conductivity, electrochemical windows, and interface stability.

For instance, the oxygen recombination in VRLA batteries, though distinct from lithium's SEI formation, provides ideas for gas management and side-reaction suppression, boosting safety and lifespan in sealed batteries.

In BMS development, while modern systems for lithium are more sophisticated, early strategies for large lead-acid packs laid foundations for monitoring, balancing, and protection. Insights into aging (grid corrosion, active material shedding, sulfation) aid accurate SOH estimation, transferable to other batteries.

Rich failure analysis from practice identifies root causes (overcharge, over-discharge, heat, defects) and solutions (alloy tweaks, charge optimization, thermal management), vital for maturing new technologies. As a standardized industrial product, lead-acid's expertise in automated production, quality control, supply chains, and cost management guides emerging tech toward commercialization.

New Positioning for Lead-Acid Batteries

Looking ahead, lead-acid development will focus on "leveraging strengths, addressing weaknesses, and precise positioning" to secure unique niches in the energy transition.

Future efforts will refine lead-carbon composites for better PSoC cycle life, charge acceptance, and low-temperature performance, while cutting costs for competitiveness in storage and start-stop systems. Innovations in bipolar and novel structures will expand high-performance potential, alongside new grid alloys, additives, and separators for gradual improvements in heat resistance and deep-cycle durability.

In smart and eco-friendly aspects, deepen BMS and recycling efficiency. In core areas like auto starting, UPS backup, and industrial vehicles, sustain market share via tech upgrades and cost controls. Proactively pursue "lead + X" hybrids with lithium, supercapacitors, etc., for optimal integrated solutions tailored to scenarios.

The lead-acid story is one of steady industrial evolution, not flashy breakthroughs. On the "fast track" of higher density and faster charging, it carves a "slow mastery" path through extreme cost control, unwavering reliability, deep safety insights, and early circular economy practice.

Due to inherent density limits, it won't match lithium's portability or fuel cells' range, but in stable, durable, economically viable domains, it's irreplaceable. In the renewable wave, it's not the surfer on the crest but the sturdy dam base, quietly enabling smooth transitions.

Lead-acid's future hinges on amplifying comparative edges via ongoing innovation and expansion, finding new balances and growth points. Its century of industrial wisdom will continue inspiring sustainable, cost-effective storage solutions.