This may sound personal, but let me go back about 20 years, when I was living in Jiangsu Province, China. I remember being puzzled by a report I came across at that time. By then, China’s motorization was already well underway. In addition, scooters powered by lead batteries were becoming popular, and demand for lead batteries for automobiles (for gasoline vehicles) was increasing. In the Shanghai–East China region, large numbers of used batteries were being generated.

 

Most of the batteries collected in East China were sent to a recycling plant in Changzhou, Jiangsu Province. After being recycled, they were sold again. However, strangely, about one-third of the batteries reportedly went missing during the transport from Shanghai to Changzhou. Why was this happening?

 

According to my Chinese colleagues, there were people who would top up used batteries with acid and disguise them as new, reselling them on the market. In other words, rather than recycling, some were secretly reusing them.

 

This was troubling. Batteries that slipped outside legitimate distribution channels essentially became bogus parts and might never return to the proper recycling system. Even if acid was added, the batteries would quickly deteriorate and eventually be discarded. But if they were discarded outside the proper channels, the lead, antimony, and sulfuric acid risked being illegally dumped, potentially causing serious environmental pollution and health damage.

 

Since then, the number of automobiles in China has skyrocketed, and consumption of lead batteries has also soared. Although China is the country advancing toward battery electric vehicles (BEVs) the fastest, the number of lead batteries being generated has not decreased. For 20 years, I carried the worry: what if more and more lead batteries were not being recycled?

 

However, attending the “9th International Secondary Lead and Battery Recycling Conference (Recycle 100)” held in Kota Kinabalu, Malaysia, on September 1, I came to understand that my concerns had been unnecessary. In particular, after listening to the lecture “Recycled Lead in China” by Dr. Dong Li, founder of Leoch International Technology Limited, I learned that lead in China is in fact being properly managed and recycled.

 

 

The company is the largest player in China’s lead recycling sector, operating recycling plants across the country. There, lead battery scrap is treated as a valuable resource, reprocessed, and prevented from leaking into the outside environment. Naturally, this is backed by two pillars: the establishment of recycling technology and economic rationality.

 

On the technology side, the process of recovering lead from lead battery scrap is already well established. After crushing the scrap and separating out fragments of plastic cases, the material is calcined to remove sulfuric components, and finally recovered as lead dioxide (PbO₂). Depending on circumstances, it may be recycled directly as PbO₂ or reused as metallic lead, but the technical challenges are relatively minor.

 

The other issue is economic rationality. For recycling to function as a business, the added value gained by turning what is essentially a waste material into something of value must exceed the cost of the process. If this condition is met, illegal dumping and pollution will no longer be issues. In this sense, my worries from 20 years ago really were unfounded.

 

The challenge now lies in how to locate and distribute recycling sites. Both in Japan and China, the importance of lead recycling is rising. Even in the age of lithium-ion batteries, demand for lead batteries is gradually increasing. Moreover, the share of batteries made from recycled lead is also growing. In other words, the demand for lead recycling is expanding.

 

How to configure the network of recycling plants is therefore a key issue. Unlike in the past, it is no longer feasible to concentrate all waste batteries in a single site such as Changzhou. Both in Japan and China, it is necessary to establish a nationwide system with multiple recycling hubs. Dr. Dong Li’s Leoch International Technology Limited operates not only across China but worldwide: three plants in Malaysia, two in Mexico, two in Vietnam, one in India, and in China—two in Jiangsu (for lead and lithium-ion batteries), four in Anhui (including one each for lead batteries, lithium-ion batteries, and UPLUS batteries), and one in Zhaoqing, Guangdong.

 

Within China, the plants are concentrated in East China and Guangdong, likely because most waste batteries are generated in the fast-developing coastal regions. Still, it is unclear if this distribution is optimal. From the perspective of investment and pollution control, concentrating in fewer sites may make sense, but from the perspective of collection costs nationwide, regional distribution is more suitable. There is also the idea of situating recycling plants near lead battery manufacturing sites. Since demand for lead batteries is steadily and slightly increasing, and the use of recycled lead is rising every year, more recycling plants are needed in China. Dr. Dong Li’s next challenge will be to reconfigure the recycling network in China and across Asia.

 

(The author asking Dr. Dong Li a question)

 

Another point Dr. Dong Li raised caught my attention. He commented that synergy effects can be realized by recycling both lead batteries and lithium-ion batteries. However, in many ways, the characteristics of the two are very different. Is there really synergy?

 

In terms of collection, automotive lead batteries are standardized in shape and size, and systems for collection and replacement are already established. A car’s lead battery is replaced several times during its service life, flowing naturally into the recycling system.

 

By contrast, automotive lithium-ion batteries vary in form and size by vehicle model and are not yet standardized. Even when performance declines, replacing them is a major operation and costly. The lifespans of the battery and the vehicle body are almost the same, meaning replacements do not occur frequently. A well-established recycling system is not yet in place. Furthermore, when no longer suitable for automotive use, they can be reused for stationary applications, making the system even more complex. Although EVs in China have increased explosively in recent years, the demand for recycling lithium-ion batteries will only surge in the future. Dr. Dong Li was right to anticipate this early and to push forward with technology development and plant construction for LIB recycling, but whether synergy exists remains unclear. In fact, his company operates separate plants for lead and lithium-ion batteries.

 

The recycling processes are very different. For lead, as mentioned, calcination, high-temperature oxidation-reduction reactions, solvent extraction, and precipitation are used to recover PbO₂. For lithium-ion batteries, however, at room temperature, solvent extraction is used to generate lithium chloride (LiCl), which is then dissolved in brine and reacted with carbon dioxide to produce lithium carbonate (Li₂CO₃).

 

With lead, key issues are preventing leakage of sulfur dioxide gas generated during calcination and protecting workers’ health from lead exposure. At the Kota Kinabalu conference, many equipment manufacturers and smelters presented pollution-control and safety-focused lead recycling systems, suggesting these issues are being addressed. The fundamentals are exhaust-gas capture and absorption systems during calcination, along with full automation using robots.

 

Separation of copper from scrap can be achieved by adding sulfur to recover it as Cu₂S. Another challenge is separating antimony (Sb) from lead. Antimony is found in the battery grids. Ideally, the grid parts could be mechanically separated during crushing, but that is unrealistic. In practice, lead paste and grid materials are recycled together.

 

As Dr. Sander Arnout of InsPyro and Dr. O.K. Ola Hekselman of Solveteq explained, the Ellingham diagram shows PbO₂ and SbO₂ lines close together, making separation by oxidation-reduction challenging, but it can be done with top-blown pure oxygen. Dr. Arnout has shown that lowering slag melting points by adjusting basicity to around 1 enables antimony separation. The Harris process using caustic soda (NaOH) or sodium nitrate (NaNO₃) is also possible. Alternatively, one can intentionally not separate antimony, producing Pb-Sb alloys instead. But with today’s soaring antimony prices, separation has become more rational.

 

(Dr. Sander Arnout from InsPyro)

 

(Dr. O.K. Ola Hekselman from Solveteq)

 

By contrast, lithium-ion battery recycling follows a completely different route. EV lithium-ion batteries may be reused first for stationary or grid storage before recycling. When recycling, they undergo dry processing—heating, crushing, screening with rotary kilns—followed by copper separation and reduction to black mass. From there, hydrometallurgical processes (solvent extraction) are repeated several times, leading to LiCl and ultimately lithium carbonate recovery. For ternary systems, cobalt sulfate and nickel sulfate are also recovered. The final steps mirror those used in refining lithium from salt lakes.

 

Compared to lead, the processes are at lower temperatures and entirely different. Unfortunately, in every presentation, the details of solvent composition and extraction conditions were withheld—understandably for corporate secrecy, but frustrating for a beginner like myself, as these were precisely what I wanted to know most.

 

In any case, how to advance the recycling of such fundamentally different materials—lead and lithium—in parallel and actually create synergy is still an open question. There were countless things I wanted to ask Dr. Dong Li, but time was far too short.

 

(The author having a further conversation with Dong Li)

 

The common theme running through the presentations by Dr. Dong Li of Leoch International, Dr. Sander Arnout of InsPyro, Dr. O.K. Ola Hekselman of Solveteq, and many others was this: the global importance of lead battery recycling continues to grow, and the importance of lithium-ion battery recycling is now being added on top of it.

 

Battery electric vehicles with lithium-ion cells are becoming mainstream worldwide. Yet for BEVs to truly gain acceptance and recognition as practical tools, their recycling systems must be firmly established. For both lead and lithium, while the technical hurdles of recycling are being steadily overcome, there is still room for debate on how to nurture recycling as an industry and how to integrate it into society’s infrastructure. Should private companies tackle these challenges individually? Should national governments take the initiative? Or should an international cooperative framework be built? Personally, I find this question deeply intriguing.

 

 

(IRUNIVERSE, Y. Akai)

 

 

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