Battery cell production uses vacuum to degas the electrode slurry and to dry the electrode coils for around 8 to 48 h, and dry rooms usually kept below 1% relative humidity, according to Fraunhofer FFB. Ultra Controlo distributes and services Elmo Rietschle, whose maker lists drying processes among the uses of its vacuum pumps; it does not name battery production.
Fraunhofer FFB, the Fraunhofer Research Institution for Battery Cell Production in Münster, describes these steps of cell production.
During dosing and mixing, a vacuum is applied to extract air bound and trapped in the mixture.
The coated foil passes through a drying oven heated by convection; the solvents are then recovered and either processed or recycled.
Coils are dried for around 8 to 48 h at low temperature and low total pressure; the vacuum dryers can be operated with inert gas such as argon.
Dry rooms keep relative humidity usually below 1%, at electrode manufacturing, electrolyte filling and assembly, which Fraunhofer FFB calls critical stages.
During and after filling, a dynamic pressure or under-pressure profile is applied to the cell to activate capillary action in its porous components.
The first charge and discharge cycles form the cell; gas is then released from hard-case cells in a degassing step, or cut out with a gas pocket on pouch cells.
Sources: Fraunhofer FFB, Battery Technology radar: Battery Cell Production, Complete Manufacturing Process, and Heatmap of cost, dry room section (battery-technology.net), read 28 October 2026.
Fraunhofer FFB describes three places where the line keeps moisture away from the materials.
A dry room is a controlled environment with extremely low humidity, usually below 1% relative humidity; it needs a continuous supply of energy, mainly for humidity control and air treatment.
Source: Fraunhofer FFB, Heatmap of cost, dry room.
Residual moisture is removed by evaporation at low temperature while a low total pressure is kept in the vacuum dryer; the coils then go on in a dry room atmosphere.
Source: Fraunhofer FFB, Battery Cell Production.
The vacuum dryers can be operated with inert gas, such as argon, an additional procedure that Fraunhofer FFB says prevents the adverse effects of corrosion.
Source: Fraunhofer FFB, Battery Cell Production.
Fraunhofer FFB does not give a dew point for the dry room; it gives relative humidity.
Equipment from the partner brands we supply, matched to the jobs in battery cell production, where Fraunhofer FFB says vacuum drying is an energy-intensive process. Where a maker names the industry, the card says so; otherwise the match is our recommendation.
For degassing the slurry, we supply oil-free, air-cooled vane pumps from 3 m³/h (V-VTE) to 154 m³/h (V-VTR), says Elmo Rietschle, which lists drying processes and environmental engineering among their applications.
Elmo RietschleFor vacuum drying of the coils, we supply oil-free dry screw pumps with an end vacuum of 0.08 mbar (abs) on the S-VSI, says Elmo Rietschle, which lists freeze drying and drying and process vacuum for the IDS series.
Elmo RietschleFor vacuum at electrolyte filling and formation degassing, we supply oil-free claw pumps; the C-VLU reaches 30 mbar (abs) with no oil or filters to replace frequently, says Elmo Rietschle.
Elmo RietschleFor vacuum ovens and degassing in the laboratory and on pilot lines, we supply oil-less diaphragm vacuum pumps; the 8311 gives up to 43 l/min at 230 V, 50 Hz, says Thomas.
ThomasFor compressed air on the cell line, we supply two-stage dry screw compressors certified ISO 8573-1 (Compressed air: contaminants and purity classes) Class 0 by TÜV; the T/TVS 90-160 gives 6.7 to 28.3 m³/min, says Gardner Denver.
Gardner DenverFor cooling circuits and demineralised water, we supply pulsation-free pumps for high pressure at low flow; magnetic-drive versions give up to 200 l/min and 90 m, says Speck Pumpen.
Speck PumpenSources: Ultra Controlo Industrial 2026 catalogue, p. 11; Elmo Rietschle, rotary vane, dry running, IDS series, screw and claw vacuum pump pages (elmorietschle.com) and Product Guide 2026, p. 9; Thomas, 8211 and 8311 series pages; Gardner Denver, EnviroAire T/TVS 90-160 kW (EMEIA); Speck Pumpen, Liquid and Vacuum Pumps in the Process Industry (brochure); Fraunhofer FFB, Heatmap of cost (battery-technology.net).
Ultra Controlo is a Portuguese manufacturer of compressed air, vacuum and technical gas systems, with 40 years of experience. We design, assemble and test our own compressors, dryers and carbon towers in Portugal, and supply and service five partner brands.
ULTRASCREW compressors, ULTRASEC and ULTRADRY dryers and ULTRAK activated carbon towers.
Gardner Denver, Elmo Rietschle, Thomas, Speck Pumpen (Circutec and SPECK Neunkirchen) and Speck Triplex.
Preventive and corrective maintenance, original spare parts and emergency support, by our own team.
Source: Ultra Controlo Industrial 2026 catalogue, pp. 3, 10, 16, 17 and 22.
Fraunhofer FFB says dry rooms keep humidity extremely low, usually below 1% relative humidity, to prevent moisture-related problems in battery components, and names electrode manufacturing, electrolyte filling and assembly as critical stages where they are used.
Fraunhofer FFB says vacuum drying of the coated coils takes around 8 to 48 h, removing residual moisture by evaporation at low temperature while a low total pressure is kept in the dryer.
Fraunhofer FFB describes vacuum during mixing to extract trapped air from the slurry, vacuum drying of the electrode coils, and a dynamic pressure or under-pressure profile applied to the cell during and after electrolyte filling.
Ultra Controlo distributes and services Elmo Rietschle, whose maker lists drying processes and freeze drying among applications of its oil-free and screw vacuum pumps. The maker does not name battery production.
Ultra Controlo supplies Elmo Rietschle dry running vane, dry screw and claw vacuum pumps; the maker lists drying processes and freeze drying among the uses of its vane and screw pumps, but not battery production. It also recommends Thomas diaphragm vacuum pumps, Gardner Denver EnviroAire T/TVS oil-free compressors and Speck Pumpen (Circutec) peripheral pumps for cooling circuits.
The process step, the vacuum level, the vapour or solvent load and the duty. We reply with the equipment that fits.
