FA_Rostprävention_per_Roboter – Polyplan-GmbH

Corrosion prevention by robot: Protecting battery packs from corrosion in the long term

Turnkey, robot-guided systems from Polyplan for cavity sealing of vehicle doors and hatches have been proving their worth in the global automotive industry for almost 20 years thanks to their process efficiency and sustainability. The company has now also adapted the technology for corrosion prevention in battery cell production – and will be presenting it at the Battery Show Europe from 18-20 June 2024 in Stuttgart (Hall 4, Stand A10).

The configuration of the system solution – from industrial robots and wax dosing to measurement and safety technology – is tailored to the individual requirements of battery pack production and the customer. It is then integrated into the production environment as a turnkey solution in accordance with the customer's standards and specifications. Polyplan's AirLess and AirMix application technologies guarantee cycle time, material and energy-efficient sealing of battery areas and parts that are at risk of corrosion and difficult to access, such as radiator connections and screw heads. This means that the cavity preservation of battery cells – as well as that for vehicle doors and flaps – fulfils all the requirements for sustainable production in the automotive industry.

Corrosion protection: an important process step in automated battery production

Polyplan-GmbH Polyurethan-Maschinen is a company of the Pepperl+Fuchs Group, which has extensive expertise in automated battery production, from the electrode to the cell and the module through to the pack. Ultrasonic sensors detect double layers of extremely thin electrode foils, stereo vision sensors recognise missing or incorrectly positioned battery cells in the pack, 3D inspection systems ensure the continuity and correctness of gap filler paths for heat dissipation – and systems for cavity preservation from Polyplan guarantee reliable corrosion prevention in the sealed and ready-to-use battery packs. As in the systems for car doors and hatches, the manual application of anti-corrosion waxes or flooding the cells in wax baths is also ruled out in battery cell production. Non-automated sealing is prone to errors and can hardly be documented, while flooding does not enable targeted application and would consume an unnecessarily large amount of wax and energy. Both methods – as well as other common spraying methods, which often use too much wax – can also contaminate the production environment due to wax carryover and result in considerable cleaning effort. All of these disadvantages can be avoided by dosing and applying anti-corrosion wax by robots exclusively to the points and areas to be protected. Weighing the dosing quantity and measuring the dosing jet also ensures maximum process reliability and resource efficiency.

High precision, minimum quantities, emission-free – sustainable wax dosing by robot

Polyplan's automatic complete systems for corrosion prevention in battery cells basically consist of an industrial robot from a well-known manufacturer, a specially developed robot hose package, a wax dispenser with wax jet dosing valve and an application lance with integrated application nozzle, calibration tip and laser sensor for position correction. If no central wax supply is available, an optional container station with drum feed can be used to ensure a constant supply of - if required, tempered and homogenised - preservative wax to the application technology. 

Before application of the cavity sealant begins, a laser sensor measures the 3D position of the battery pack to ensure precise and collision-free path control of the robot in places and areas that are often difficult to access. At the same time, the position of the mould zero point is checked and corrected and the nozzle position and orientation are measured. Depending on the desired application pattern, the orientation of the wax jet is now checked – for the spray-air-free, pinpoint AirLess application – or the geometry of the spray cone is defined – for surface wetting in the patentet AirMix process. It is possible to switch between the two methods while the process is running – in addition, they can be infinitely varied in terms of discharge quantity and switched on and off without dripping. In the wax dispenser, a self-calibrating scale determines the dispensing quantity with high accuracy and records the target quantity, measured quantity and weighed quantity at different dispensing rates. The robot then guides the application lance with the application nozzle into the battery pack with high precision and applies wax to the desired points and areas. For example, the wax can be applied from a distance of 500 mm with a precision of ± 1 mm. This only requires a minimal amount of around one gram per metre of seam length (1 g/m) – in other words, high-quality, long-term corrosion prevention is achieved with extremely low wax consumption. As no aerosols are released during application, there is no need for time-consuming and cost-intensive extraction – which is reflected not only in cost savings but also in shorter cycle times.

Cost-efficient processes, future-proof system technology

No wasted material thanks to efficient application processes, no expensive tool changes when changing the application strategy, no contamination in the production environment due to overspray and wax carryover, no extraction of aerosols, no complex system maintenance – Polyplan's robot-guided systems for corrosion prevention in battery cell production guarantee cost-efficient processes in every respect. And this right from the start – because Polyplan's in-house robot laboratory and process technology centre can test the feasibility of applications and possible system concepts at an early stage, for example with regard to application strategies or the suitability of certain preservation media. After completion, each system is set up at Polyplan for joint pre-commissioning with the customer before delivery. This largely eliminates project risks and ensures the shortest possible installation and commissioning times at the final installation site. In operation, the system solutions are characterised by a high level of investment and future security due to their sustainability, scalability and easy convertibility to new types of battery cells. In general, they are also suitable for other tasks in which small quantities of liquid media are to be applied with high precision.

Facts, figures and data on minimum quantity corrosion prevention for battery cell production

+ Material-saving application of preservatives to corrosion-prone areas in battery cells such as cooling connections and screw connections
+ Robot-guided nozzle and precision application process ensure accessibility even to hard-to-reach areas
+ Liquid output variably adjustable from 300 - 3,000 mg/s 
+ Smallest shot size 12 ms – therefore even minimal quantities can be dosed
+ Suitable for both 100% wax and water-based protective waxes
+ Two available and switchable application methods: AirLess – spray air-free – for precise spot or seam application; AirMix – spray air – for wetting surfaces and contours
+ Both processes can be switched on and off without dripping
+ Spray air pressure in the AirMix process is infinitely adjustable between 6 bar and 12 bar
+ Application distances between 5 mm and 500 mm – beyond this on request
- the full functional scope of the system is integrated into the production environment as a turnkey solution without interface risks and in accordance with applicable factory standards and process regulations.
+ to be seen at the Battery Show Europe from 18 - 20 June 2024 in Stuttgart (Hall 4, Stand A10)

Press contact

Polyplan-GmbH Polyurethane Machines
Head of Sales, Aftersales and Marketing
Mr Jan Jacobi
Mitterstrassweg 23

D-82064 Strasslach

Phone: +49 (0)8170 - 9305 - 48
Fax: +49 (0)8170 - 9305 - 55

Email: jan.jacobi[at]polyplangmbh.de
Internet: www.polyplangmbh.de