China: battery precursor technologies? 

When you hear “Chinese precursors for batteries?”, the first thought is volumes, prices, maybe even copying. But over the past five to seven years the picture has become much more complicated. Many people still think that everything is simple here - they took Western patents, scaled it up, and it’s done. In fact, if you dig into the value chain, especially in the area of ​​materials for lithium-ion and new solid-state systems, you can see that Chinese players are no longer just “doing”. They are actively conducting R&D, often in directions that were considered dead ends in the West due to the high cost of the process. But more on that later.

From ?made in China? to “designed in China”: an evolution of the approach

Previously, about ten years ago, indeed, a lot was built on reverse engineering. We purchased samples of lithium cobaltate (LCO), nickel manganese cobaltate (NMC), disassembled them, and tried to repeat them. But the purity and stability of the parties was a constant nightmare. I remember in 2015-2016, conversations with technologists at one of the sites in Changsha boiled down to one thing: “the parameters seem to be according to the specifications, but the output battery gives a variation in capacity of 5-7%?”. The problem was not in the formula, but in the subtleties of the synthesis of precursors - control over particle size, morphology, and impurity content at the ppm level.

The shift began when major battery manufacturers such as CATL and BYD began to impose stringent requirements not just on the chemical composition, but on the functional characteristics of the material. They needed not just nickel-cobalt-aluminum (NCA) powder, but a material with a certain porosity that would provide better ionic conductivity in the finished cathode. This has forced precursor supply companies to invest in their laboratories and pilot lines. Here we are no longer talking about copying, but about customizing processes ourselves - carbothermic reduction, hydrothermal synthesis, co-precipitation methods with precise control of pH and temperature.

An interesting case is the development of chains for NMC 811 (with a high nickel content). The pursuit of high energy density is obvious, but along with nickel, problems also grow - thermal stability decreases, cation displacement in the layered structure. Chinese engineers not only followed the path of alloying (adding aluminum, magnesium), but also began experimenting with a gradient coating of precursor particles - the core is richer in nickel for the container, and the outer layers are enriched with manganese or cobalt for stability. This requires precise control at the stage of precursor synthesis. I saw samples from one supplier from Sichuan - their approach to multi-stage deposition was really impressive, although at that time (a couple of years ago) the yield on the pilot line was catastrophically low, about 65%.

Where the real difficulties lie: not chemistry, but engineering

Many focus on chemical formulas, but the main battle right now is in chemical engineering and scaling. You can get a kilogram of an excellent precursor for LFP (lithium iron phosphate) with an olive structure in the laboratory. But when you try to scale up to 10 tons per month, miracles begin: agglomeration of particles, uneven distribution of alloying elements, fluctuations in bulk density. This kills the economics of the project.

Here, Chinese companies began to show their strengths - flexibility and speed of iteration. They often don't have gigantic, once-for-all factories. There are modular pilot lines that can be quickly reconfigured. A familiar technologist fromChengdu Yizhi Technology Co.(this is a design institute created by Huaxi Technology) once said that for one European customer they tried three different reactor configurations for the synthesis of a sulfide electrolyte precursor (for solid-state batteries) before reaching an acceptable purity of the product. Their websiteyzkjhx.rurather stingy with details, but from the project descriptions it is clear that they are deeply involved in the development of turnkey processes. - from laboratory to commercial production.

Another sore point is raw materials. Dependence on imports of cobalt and lithium has not gone away. Therefore, enormous efforts are aimed at two directions: firstly, deep processing and recycling in order to squeeze the maximum out of secondary raw materials; secondly, to develop materials that reduce this dependence. Sodium-ion batteries can be considered a breakthrough in recent years. And here China seems to be trying to seize the initiative not only in the production of elements, but also in creating a chain of precursors for them - for example, layered oxides or polyanionic compounds. CATL has already announced commercial products. But if we talk about precursors, the key challenge is the stability and low cost of synthesis. There are laboratory successes, but what will a tonnage batch look like? There are still more questions than answers.

Solid-state batteries: a new race and old problems with precursors

This is where the most interesting, but also murky area is now. Everyone talks about solid state batteries (SSB) as the holy grail. But if we move away from the hype, the main technical problem is the interfaces. The solid electrolyte (sulfide, oxide, polymer) and the electrode material must be in perfect contact. And this again comes down to precursors.

For sulfide electrolytes (e.g. Li₂S–P₂S₅systems) we need highly pure precursors, and the synthesis must take place in a completely inert atmosphere - oxygen and moisture kill everything. Chinese companies, such as the same Chengdu Yizhi Technology Institute, are actively working on methods of solid-phase synthesis and mechanical alloying on an industrial scale. But the main snag is not the synthesis of the electrolyte itself, but the creation of precursors for composite cathodes. One needs to uniformly deposit the active material (say, NMC) onto the sulfide electrolyte particles to create an ionically conducting matrix. Standard mixing methods do not work - they create “dead zones”. The solution is seen in the development of specialized precursors, where the desired structure is formed in situ, at the synthesis stage. I have heard of attempts to use atomic layer deposition (ALD) techniques adapted for mass production, but so far it is expensive and slow.

A failed attempt that few people talk about is the early projects on oxide electrolytes such as LLZO (lithium lanthanum zirconium oxide). The material is promising, but its precursors require high-temperature sintering (above 1200°C). They tried to establish synthesis, but were faced with enormous energy consumption and the problem of controlling the stoichiometry of lithium - it simply evaporates at such temperatures. As a result, many startups curtailed or froze these areas, switching to sulfides or hybrid systems. This is a good example of beautiful laboratory chemistry encountering insurmountable engineering and economic barriers at the precursor level.

Looking to the Future: Chain Integration and Ecology

The trend that will become decisive is vertical integration. Large players like CATL or Gotion High-Tech no longer just buy precursors, but invest in joint ventures with their manufacturers or build their own facilities. For what? To control the entire chain - from raw materials to the finished electrode. This makes it possible to finely optimize parameters for a specific cell architecture (for example, for tablet or bag cells).

The second big topic is environmental friendliness. European regulators have long been putting pressure on the topic of carbon footprint and responsible sourcing. For Chinese suppliers, this is not only a threat, but also an opportunity. I see many people starting to certify their processes, introducing solvent recycling systems in the production of precursors, and working on “green” ones. synthesis methods - say, using less toxic reducing agents or in aqueous environments. This is no longer PR, but a dire necessity to enter global markets. Chengdu Yizhi Technology Co., Ltd., with its registered capital of 120 million yuan and the status of a design institute, is one of those that can offer customers not just a product, but a technology with a calculated environmental and economic balance.

And one last thing. You shouldn't expect any one "killer" thing. breakthrough in precursor chemistry. The evolution will be gradual: an improvement in purity by 0.5%, a reduction in the cost of synthesis by 3%, an increase in the shelf life of the material in air. It is in this painstaking, invisible work - control over thousands of parameters, iterations on pilot lines, solving scaling problems - that China's leadership in this area lies today and tomorrow. They have already gone from imitators to serious competitors in process engineering. The next step is perhaps to become trendsetters in the design of the materials themselves, but this requires fundamental discoveries. And they don't happen according to schedule.