Japan’s 90% Lithium Recovery: The Chemistry Behind EV Recycling

Picture a future where EVs are everywhere, but the recycling process can’t keep up. That disconnect is already showing up in the real world: batteries wear out, packs get retired, and valuable materials end up waiting in landfills longer than they should.

Against that backdrop, Japan’s battery-recycling community has been working on a tougher goal than “remove some metals.” The aim is to recover lithium at a rate high enough that it can realistically flow back into new lithium-ion batteries. And according to recent project updates and process results, one approach can recover about 90% of lithium from used EV battery material.

Why does a number like “90%” matter so much? Because lithium isn’t cheap, it’s not evenly available around the planet, and building recycling that returns high-purity material is the bridge between environmental promises and actual battery manufacturing.

The starting point: what you get when a battery is “done”

When a lithium-ion battery is removed from a vehicle, it doesn’t look like a tidy recipe. It’s an assembly of metals, plastics, electrolytes (the liquid inside), binders (the glue inside electrodes), and—most importantly—active materials from the cathode (the positive electrode).

Most recycling flows eventually reach a material called black mass. “Black mass” is a dark, metal-rich powder made by breaking down and thermally treating spent lithium-ion batteries so the metals and lithium-bearing compounds become concentrated in a smaller, processable form.

At that point, the recycling question turns into something more chemical than mechanical:

• How do we dissolve lithium (and other metals) out of black mass?
• How do we separate lithium cleanly from everything else?
• How do we make the recovered lithium suitable for battery-grade use?

That’s where hydrometallurgy enters.

Hydrometallurgy means using water-based chemical reactions to extract metals. Instead of melting scrap in a furnace (which is common in some metal recycling), hydrometallurgy dissolves target materials into a liquid and then recovers them from that solution.

The “small” tweak that changes the whole process

A typical lithium-ion battery recycling route for lithium uses a chemical step often described as caustic leaching. “Leaching” means letting a reagent react with the material so lithium-containing compounds dissolve into solution. “Caustic” points to strong alkaline chemistry (high pH conditions).

This is where a concept called pH shows up.

pH is a scale that describes how acidic or basic (alkaline) a liquid is. Lower pH means acidic; higher pH means basic. Many metal dissolution and selectivity behaviors depend on pH, because pH controls which chemical forms of lithium stay soluble and how other metals behave.

Traditionally, some recycling processes adjust pH using sodium hydroxide (a strong base). Sodium hydroxide is effective, but it comes with side effects:

• It introduces sodium into the chemical system.
• Downstream purification may need extra work to reach battery-grade lithium purity.
• The overall environmental footprint can grow because extra chemicals and handling are required.

Japan’s approach changes a key variable: instead of using conventional sodium hydroxide as part of the pH adjustment, the process uses recovered lithium hydroxide.

Lithium hydroxide (LiOH) is a lithium-containing base. In battery supply chains, lithium hydroxide is also a familiar intermediate for producing battery-grade lithium chemicals.

So the core idea is almost poetic in its simplicity: use lithium chemistry to recover lithium.

What the chemistry accomplishes

In hydrometallurgical processing, the goal isn’t only to dissolve lithium. The goal is to dissolve lithium in a way that makes it easier to recover as a purified product.

By using recovered LiOH for pH adjustment, the process can improve product purity—meaning the lithium product contains fewer impurities that would otherwise interfere with battery-quality standards.

And in reported testing, the lithium recovery rate reaches around 90%, a leap compared with older baselines that often landed below that level.

From lithium recovery to “battery-to-battery” potential

Recycling becomes truly valuable when the recovered output can feed back into manufacturing. That’s often called closed-loop recycling or battery-to-battery recycling.

Closed-loop recycling isn’t just about “getting materials back.” It’s about getting materials back in a form that’s practical for new battery production without starting from scratch.

That’s why purity is such a big deal.

Even if a process extracts lithium successfully, the recycled lithium must usually meet tighter specifications:

• low impurity levels (metals and contaminants that can affect performance)
• appropriate chemical form (for subsequent conversion steps)
• consistent quality so manufacturers can run standard production lines

When a process also reports a meaningful reduction in carbon footprint (a measure of greenhouse gas emissions), it highlights a second advantage beyond yield. In other words, the “90%” headline isn’t only about more lithium—it’s also about how efficiently the process runs.

One project update reports that the approach can reduce carbon footprint compared with a conventional process by roughly 40%, largely by minimizing chemical usage through the lithium-based pH strategy.

The part nobody sees: collection still limits recycling

A high-performing chemical process can’t fix a supply problem.

To recycle EV batteries at scale, used batteries must actually show up in the recycling system. That requires collection networks, logistics, and sorting.

Japan’s recycling pipeline faces a similar challenge seen in many countries: large volumes of retired lithium-ion batteries don’t always flow into official routes quickly.

Recent analysis for Japan has estimated that only about 14% of end-of-life portable lithium-ion batteries were collected through existing collection schemes. While portable batteries aren’t identical to automotive packs, this still signals how collection effectiveness can lag behind technological capability.

For EVs, the collection problem can be different in details (vehicle channels, dismantling infrastructure, regulated handling), but the underlying reality remains: without consistent input, even the best extraction process can’t run at high capacity.

When does this become real production?

Lab results are encouraging, but the path to widespread impact runs through pilot and mid-scale validation.

Project updates place this kind of work on a timeline that includes demonstration and validation moving into larger facilities, with plans tied to mass-production validation beginning in April 2027 at a targeted facility.

That kind of schedule matters for two reasons:

1. It tests whether the method maintains performance under real throughput, variable feedstock, and plant constraints.
2. It pressures the chemistry and purification steps to stay stable over time, not only in controlled experiments.

And that stability is where many recycling technologies either earn their reputation—or quietly stall.

Why people keep chasing lithium selectivity

At this point, it’s tempting to think lithium recovery is “just” another extraction problem. But lithium is trickier than it sounds, because it sits in a chemical neighborhood crowded by other metals.

A good recycling flow has to manage separation, selectivity, and purification:

• dissolve lithium while keeping other metals less soluble (or dissolving them differently)
• separate lithium from a mixture that can include nickel, cobalt, manganese, and more
• recover lithium in a form suitable for future battery manufacturing

So the bigger lesson from Japan’s approach is not only that a certain yield is high. It’s that small changes in the chemistry can improve selectivity, purity, and efficiency in one stroke.

The big takeaway

A breakthrough in EV recycling doesn’t always look like a brand-new invention. Sometimes it looks like a single decision in the middle of a chemical process: swapping sodium hydroxide for recovered lithium hydroxide during pH adjustment.

That decision can raise lithium recovery toward 90%, support high-purity output suitable for reuse, and reduce overall chemical and carbon burden enough to matter.

But recycling at scale still depends on the messy front-end work: collecting batteries, sorting them safely, and feeding consistent material into plants.

The most hopeful part is that this kind of chemistry is now being positioned for mid-scale validation on a production-adjacent timeline. If the process keeps its performance when the inputs get less controlled and the throughput gets higher, “recycling lithium” may move from a promise to a reliable supply route for future EVs.