An Inevitable Shift in Lithium Battery Manufacturing: The Evolution from Wet to Dry Electrode Processes

Over more than a decade of rapid expansion in the lithium-ion battery industry, wet electrode manufacturing has become the de facto standard. Mature and reliable, it has supported the large-scale commercialization of both power batteries and energy storage systems. However, as requirements related to safety, cost, energy consumption, and environmental compliance continue to intensify, the limitations of this process are becoming increasingly apparent. Against this backdrop, dry electrode technology has gradually moved from laboratory research into industrial consideration, and is now widely regarded as a key direction for the next stage of battery manufacturing.

1. The Growing Impact of the “Hidden Costs” in Wet Processes

Traditional wet electrode manufacturing is centered on slurry preparation, where active materials, conductive additives, and binders are dispersed in organic solvents before coating. In the early stages of industry development, this approach offered clear advantages in process stability and scalability. Yet under large-scale manufacturing conditions, its structural shortcomings have become more pronounced.

One major issue lies in safety and environmental pressure. Wet processes rely heavily on organic solvents such as NMP, which are both toxic and volatile. As a result, production lines must be equipped with complex solvent recovery systems and explosion-proof infrastructure. These systems require significant upfront investment and ongoing energy consumption, while also limiting factory layout flexibility and expansion efficiency.

In addition, manufacturing costs remain rigid. The drying stage is typically the most energy-intensive and time-consuming step in electrode production. To meet high-throughput demands, long-duration, high-temperature drying becomes unavoidable, embedding substantial energy consumption and carbon emissions into each battery cell produced.

2. Dry Electrode Technology: More Than Simply “Removing the Solvent”

At first glance, the most visible change in dry electrode processes is the elimination of liquid solvents. In reality, however, the transformation runs much deeper, fundamentally altering how electrodes are formed.

In dry processes, binders undergo fibrillation through mechanical shear and calendering, creating a stable three-dimensional network that binds active materials together. This structure avoids solvent migration and drying-induced stress, allowing the electrode to achieve mechanical integrity at the forming stage itself.

From a manufacturing perspective, this shift leads directly to a simplified process flow. Dry mixing, film formation, and lamination replace slurry preparation and drying. With the drying step removed entirely, production lines become shorter, equipment counts are reduced, and manufacturing throughput is significantly improved.

3. Safety and Consistency as Practical Advantages

In real-world applications, the most immediate benefits of dry electrode manufacturing are often found in safety and product consistency.

Without organic solvents, the risks of fire and explosion during production are substantially reduced. Workshop design no longer depends on high-level explosion-proof standards, making operations safer and more manageable for both personnel and equipment. Meanwhile, VOC emissions are nearly eliminated, easing long-term environmental compliance pressures.

From a product standpoint, dry electrodes avoid common issues associated with wet processes, such as slurry sedimentation, uneven drying, and electrode cracking. The internal structure of the electrode becomes more uniform, with reduced batch-to-batch variation—an advantage that is particularly critical in large-scale production.

4. A Practical Path for Thick Electrodes and High Areal Density Designs

As application demands continue to rise for higher energy and power density, thick electrodes are becoming increasingly unavoidable. However, wet processes face inherent challenges in this area, including limited drying efficiency and the risk of internal defects.

Dry electrode manufacturing, free from solvent diffusion and evaporation constraints, demonstrates greater adaptability to thick electrodes and high areal density designs. This opens up greater process flexibility for high-energy cells, high-power applications, and emerging material systems.

5. Industrialization Challenges Remain, but the Direction Is Clear

It must be acknowledged that dry electrode technology is not without barriers. It places higher demands on equipment precision, binder systems, and process window control, and typically requires a longer optimization phase during early deployment. Nevertheless, once stabilized, its advantages in cost reduction, energy efficiency, and scalable manufacturing become increasingly pronounced.

From an industry perspective, dry electrode technology is not simply a replacement for wet processes. Instead, it represents a more sustainable manufacturing pathway for the next generation of lithium batteries.