Nothing less than perfect.
Dryer
Drying is not just drying: we not only know this, we measure it and plan each individual system individually. Because the quality of the electrode drying process determines the performance of the finished lithium-ion battery cell.
Drying process
- Convection drying
- Infrared radiation (IR)
- Near infrared radiation (NIR)
- Laser drying (coming soon)
Selecting the drying process: it's the optimum that counts
When it comes to finding the optimum process for individual anode and cathode drying requirements, we leave nothing to chance. Based on process and material data from the previous coating process, our experienced engineers define the perfect process for the job.
To do this, they use relevant variables as the basis for the system design.
Variables during the drying process
Physical variables | Outlet velocity of the nozzles |
Air temperature | |
Material variables | air properties |
Nozzle Type | Venturi / WebConStar |
Flotation / FlowStar | |
Perforated plate / LaminarStar | |
Geometric variables | Distance between nozzles |
Size of the slots | |
Distance between nozzle and substrate |
Further information
You can find more detailed information on the subject of "Drying" in our data sheet.
Download "Drying technologies" data sheet
Theory meets practice: the key to perfection
In close cooperation with universities and research institutes, we combine theoretical basic research, the latest developments and years of experience to create ground-breaking practical possibilities. Because when drying substrates coated with micrometer precision, little things make a big difference.
Our own drying nozzle
Our self-developed WebConStar nozzle allows us to combine effective drying and optimum web guidance. We use the Venturi effect.
Background knowledge: Drying and analysis methods
Drying describes the transfer of energy from a solid surface and the adjacent liquid or surrounding moving gas. The combined effects of convection and fluid movement come into play here: the greater the movement of the fluid, the greater the convection heat transfer. The speed at which the heat is transferred (heat transfer rate) is just as decisive for drying as it is difficult to determine. It is described by the heat transfer coefficient hconvection (HTC).
Venturi effect
In industrial convection drying, a variety of nozzles are available. They vary in their form, and most importantly in the way they guide the drying air towards the wet substrate.
For dryer design and process optimization, knowing the available drying capacity, i.e. the heat transfer coefficient (HTC) for each nozzle and parameter set is crucial.
We use CFD simulations to calculate the HTC and the air distribution inside the dryer. Computational fluid dynamics simulation is a numerical method that uses the 2D or 3D variables of the CAD file of the specific system.
We test the uniform distribution of speed and flow volume of the nozzles. We also use CFD to determine the pressure loss in the entire drying module.
The result is a local and averaged HTC, which defines the drying process of your application.
fig. 1 | fig. 2 | fig. 3 |
Once we have determined the heat transfer coefficient for the dryer geometry, we can calculate and ultimately implement the optimum drying process for a specific product.
We use the following process parameters for the simulation run:
- Coating:
- Coating weight [ kg x m-2 ]
- Solid content [ Weight % ]
- Solvent type
- Substrate:
- Substrate weight [ kg x m-2 ]
- Substrate type
- Web speed
- Web temperature
- Fresh air temperature
The curves show the temperature profile, the drying rate and the residual moisture content over the drying section.
fig. 1 | fig. 2 | fig. 3 |
Simulation of the drying process with DrySign®
At the end of our comprehensive analyses is the simulation of the individual drying solution. It allows conclusions to be drawn about your efficiency and any weak points even before we implement the concept technically.
We create a process and instrument diagram for this purpose:
- Incoming fresh air volume flow
- Exhaust air and fresh air in each section
- Required heating capacity
- Required fan output
- Exhaust air temperature
We use our proprietary DrySign drying simulation software for this. It is able to simulate the drying of single-sided, double-sided and even multi-layer coatings and even take diffusion effects into account. This final simulation forms the basis for further adjustments as well as the final design and its technical implementation.
Our drying solutions in practice
Would you like to find out more?
Our experts are looking forward to speaking to you in person!