The lead battery was invented in the 19thcentury. Today, in the 21stcentury, it remains the most commonly used rechargeable battery, in spite of the emergence of newer technologies such as lithium-ion. When it comes to key performance indicators – safety, reliability, sustainability, and initial cost ($/kWh) – the lead battery has few competitors, whether for powering our cars, providing standby power, or storing energy to optimize new renewable inputs.
The lead battery hasn’t just survived. The industry is accelerating the pace of innovation and improving performance factors such as cycle life, water loss, self discharge, internal resistance, and charge acceptance – all of which directly impact safety, reliability, sustainability, and costs in a market expected to reach $84.46 billion by 2025.
Lead batteries have an unmatched record for safety. Lithium-ion batteries, on the other hand, continue to have significant safety issues in both electric vehicles and grid storage applications. Even if the lithium industry continues to improve on safety issues—like self-combustion—it is unlikely to site commercial- and grid- scale lithium batteries in dense urban settings (such as the basements of Manhattan high-rises) due to the inherent flammability of lithium material.
Lead batteries have been relied upon extensively for 160 years. They’re used in a wide range of temperatures and operating conditions; due to their higher reliability, even fully-electric vehicles (with lithium-ion batteries) use 12V lead batteries to power their most critical computer and electronic controls.
According to Battery Council International, more than 99 percent of the lead batteries in the U.S. are recycled - all of the materials can be reused. In fact, more than 60 percent of the lead used by lead battery manufacturers in the U.S. comes from recycled batteries instead of virgin lead material.
Because they can be economically recycled, lead batteries have high residual value, which further reduces their economic cost. Compare this to lithium batteries, which only have about a 5 percent recycle rate. Improving the recycle rate for lithium-ion batteries will likely require a significant subsidy, but this is not cost competitive with virgin sources, and will only add to the battery’s costs. Usually, the recycling of lead batteries is included in their price; for Li-ion batteries, this is not the case.
Additionally, lead batteries are greener than lithium-ion; they have less embedded energy and carbon dioxide in their manufacture, are sourced and recycled in North America, and are not dependent on foreign, and possibly unstable sources for raw materials.
Though certain storage battery systems can be comparable in cost, the initial cost per kWh of lead batteries is generally about 1/3 that of lithium-ion batteries. But if lead is more cost effective, why isn’t it used more widely in grid storage? In fact, it is becoming more widely used – the Consortium for Battery Innovation website (http://www.batteryinnovation.org) highlights lead battery applications for grid storage with a searchable map of installations. Lead batteries continue to be the standard for grid backup power in applications such as data centers, hospitals, and telecom. Lithium has gained more recognition recently for newer applications such as frequency regulation and time shifting of renewable energy supply—specifically solar and wind—but lead batteries are proving effective and cost-competitive in these applications as well.
Major Innovations in Lead Battery Technology
As the North American lead battery industry continues to accelerate innovation with increased battery lifecycle and other performance improvements, the gains in safety, reliability, and sustainability will not only make lead more competitive with lithium, but—just as importantly—it will help manufacturers and other high energy consumers reduce costs and grow their bottom line.
Argonne National Lab – the premier Department of Energy National Lab focused on battery technology – has established an industry collaboration with 14 U.S. lead battery manufacturers and suppliers to continue this drive for innovation. With this public-private partnership leading the way, the market can soon expect to see critical advancements in areas such as battery design, carbon technologies, lead oxide technologies, and new electrolytes.
Bipolar lead battery test results demonstrate improved AGM battery lifecycle in the range of 3-4x, while also improving energy density by 40 percent. Several top global lead battery manufacturers are taking advantage of this newer technology.
Advanced carbon technologies are substantially improving charge acceptance and cycle life in many applications. There are several carbon suppliers that are improving battery performance without sacrificing on other factors such as safety, reliability, sustainability, or costs. Specialized carbon materials improve durability and performance of batteries for hybrid and electric vehicles, and for grid-level electricity storage.
Lead Oxide Technologies
Lead battery manufacturers are the biggest consumers of lead, with different types of oxide to meet specific product characteristics such as acid absorption, water absorption, and tamped density values related to the reactivity of the oxide.
Since the invention of lead batteries, sulfuric acid has been the electrolyte used as the third active material, but this is one area where innovation can transform the lead battery for the 21stcentury. Electrochemical cyclometric tests have shown that replacing the sulfuric acid in lead batteries reduces parasitic reactions on both positive and negative electrodes, and may offer significant performance improvements on severalcritical lead battery performance parameters including water loss, charge/discharge resistance, and self discharge.
The lead battery technology innovations in bipolar battery design and materials - including carbons, lead oxides, and electrolytes - has the potential to improve lead battery performance in deep cycle stationary storage applications by 5 to 10x in the next few years as these technologies are realized in volume commercial products.
Lead batteries have proven their effectiveness for 160 years because they get the job done simply and efficiently. Furthermore, this established and mature market is on the verge of real transformation. The future of the lead battery industry is as promising – and electrifying – as any of the newer technologies on the market.
Paul Bundschuh is CEO of Tydrolyte, which innovated an electrolyte solution for automotive and stationary storage lead battery manufacturers. Tydrolyte’s chemistry replaces toxic sulfuric acid in lead batteries for safe and sustainable energy storage.