What changes will happen to lithium batteries production line through planar infrared heating technology?

7/7/2025

In the current lithium battery manufacturing site, the most "heavy" part of the process is still the drying stage after coating. Ovens are often reach 60 to 70 meters long. The boilers,
Thermal transfer oil pipelines and maintenance passages covers an huge area of workshop.

Hot-air drying technology, with its mature technical path and strong system compatibility, has long been the common choice in the field of pole piece drying. Although there is room for improvement in energy consumption, carbon emissions, and control efficiency, it is still widely used at present. As some enterprises begin to deploy localized production capacity overseas and carry out advance calculations of carbon taxes, ESG management, and plant space constraints, the requirement of system optimization issues is quietly increasing.

On June 25th, at the Battery Application Special Session of the 18th Gaogong Lithium Battery Industry Summit, Dr. Song Qi, our deputy general manager of RESO New Materials, delivered a keynote speech on "New Generation High-Efficiency Coating Drying Technology: Opportunities and Changes Brought by Planar Infrared", systematically introducing the planar infrared drying system and elaborating on its application in terms of energy conservation, efficiency improvement, consumption and land occupation reduction.



How much room for cost reduction in hot air drying? Dr Song Qi stated the problems of current hot air oven system, points out that the hot air drying behind "dominant" cost of investment, energy consumption, and the "potential"carbon tax cost. "We see now is a few hundred meters of drying oven , behind have to match system of boiler, piping, heat exchange equipment. The combined area occupied by these systems may exceed 4,000 square meters. He mentioned that this part is an important influencing factor in the design and construction investment of the factory, but it is often not reflected in the configuration of core equipment on the production line.

Another cost point that has been repeatedly emphasized is energy. The drying process accounts for approximately 15% of the overall carbon emissions of lithium batteries. Whether it is to reduce the carbon footprint of the system or to meet the ESG requirements of overseas projects, the drying section cannot be ignored.

"Hot air drying consumes a vast amount of fossil energy," he said, citing calculation data. If the annual battery production is estimated at 1.5 TWh, the drying process could generate more than 230 million tons of carbon emissions.

Although carbon tax has not been widely implemented yet, based on a carbon price of $25 per ton, it would be a potential cost of nearly $600 million. If the carbon price rises to $100 per ton in the future, its impact will further increase.

In response to this issue, the solution proposed by RESO is to replace the traditional hot air system with our infrared module, and complete the drying process after coating through the "electricity-induced radiation" method.

Dr. Song Qi introduced that the new generation of planar infrared drying system released by RESO, we use self-developed graphene materials as the heating source, combined with medium and long-wave infrared radiation, to construct a large-area, close-range heating method.

"We adopt a planar heating structure instead of the traditional point or line heating of infrared," he pointed out. This design enables the infrared module to be close to the surface of the coated materials, with minimal energy loss and a significant improvement in heat exchange efficiency.



The infrared conversion efficiency of the RESO infrared module has reached over 80%, and it can achieve the heating target within the temperature range of 200 to 300℃. The system supports module assembly and compatible with various process sections such as cathode and anode electrodes, separators, and thick coating.

Our Infrared drying system has the following key technical benefits:

The first, over 50% of energy saving: the infrared as the only heat source, cancel the wind heating structure, energy consumption greatly reduced;

The second, drying efficiency more than 40% improving: the closed range heating to realize more rapid, uniform drying process, support higher coating speed;

The third, the drying oven shorten by 30% ~ 50%, unit drying ability improve the capacity so that can enhance workshop space utilization, decrease the cost of civil engineering and equipment integration.

In addition, the infrared module is fully enclosed structure, completely isolated from air ,moisture and solvent, the design of lifespan is over 20000 hours; We have developed a variety of modules, including high-power type, water-based material compatible type, explosion-proof type, etc., to meet the diverse needs of different customers.

At the same time, we are also researching the the second generation of infrared module, which is expected to further enhance energy efficiency and adaptation ability.

In practical applications, we began to promote the planar infrared technology industrialization since 2022, so far, we have delivered more than 200 sets of systems, more than 30000 pieces of planar modules, total provide more than 20 service customers, Our delivery includes both new equipment installed and the modification of the original hot air system by embedding our modules.



In terms of energy adaptation, its 100% electric drive architecture can seamlessly integrate with clean energy sources such as photovoltaic and wind power, providing a flexible green energy access solution for lithium battery production lines.

In regarding the system design level, completely abandoned the boiler, pipe network and heat exchange system structure, not only enhanced the plant layout space utilization, but also reduced more than 30% of the cost of equipment maintenance;

From the safety point of view, we can avoid the common gas heating approval of overseas project barriers, reduce the financial burden on multinational capacity deployment cycle.

From the energy input to the process of the systematic refactoring, are reshaping the li-ion battery technology paradigm of drying part. It can be foreseen that in the future, when lithium battery enterprises are making overseas plans, conducting carbon emission simulations or evaluating process energy conservation, RESO infrared drying technology will become a key variable to achieve those goals.