SAMPE Journal - September/October 2020 - 28

FEATURE / AUTOMOTIVE ENGINEERING WITH PL ASMA

Figure 1. The highly effective, process-reliable and fully automated plasma
treatments from Plasmatreat are key technologies in the production of electric drive and storage systems for the electromobility sector.

the industry. Openair-Plasma technology is now
firmly established as a key technology in an ever-increasing number of applications; several leading automotive manufacturers have now integrated it permanently into their production lines. This
success can be attributed to the ease-of-use, high
effectiveness and in-line capabilities of plasma
treating processes. They enable plasma treatments
to be performed under normal pressure, are fully
automatable and can be incorporated into existing
manufacturing processes with ease. Furthermore,
they guarantee perfectly pretreated surfaces, maximum process control (including traceability) and
area-selective applications - with the added benefit of low running costs.
HIGHLY EFFECTIVE PLASMA CLEANING AND
ACTIVATION
Whether for vehicle sensors, battery modules/battery packs or electric vehicles, plasma treatments
using these technologies are key to progress in
the automotive industry. Possible applications
range from pretreating structural bonds with Openair-Plasma, sealing sensitive electronics and pro-

ducing flawless paint finishes to using PlasmaPlus
nanocoating to create highly effective functional
coatings.
Innovative plasma technology processes also
come into their own in the production of electric
drive and storage systems as shown in Figure 1. The
long-time stability of a battery pack is one of the
most important factors when it comes to electromobility today. The battery's thermal management
system and the insulation of individual battery
cells are critical in this respect. To prevent an internal short-circuit, the bonding medium between
the individual cells in a cell stack must have an insulating effect. Consequently, polyurethane adhesives are normally used for this purpose. Microfine
cleaning and activation of the outer casing of the
cell (normally aluminum) is essential to achieve a
precise insulating bond with optimum adhesive
characteristics, because aluminum and other metals are often contaminated with undefined oxide
layers, wafer-thin layers of dust or traces of residue from the production process such as release
agents, lubricants, cutting oils and drawing grease.
These impurities diminish the effectiveness of the
surface energy naturally present in the aluminum
which largely determines the strength of an adhesive bond.
Plasma cleaning removes dust deposits, oxide
layers, grease and other contaminants. After cleaning, the surface energy of the substrate is restored
to optimum levels to ensure complete, homogenous wettability of the treated surface with paints
or adhesives. The high energy level of the plasma
can fragment the structure of chemical and organic
substances on the surface of the material in a targeted manner. Furthermore, the deionizing effect
of the plasma beam neutralizes loose particles of

Figure 2. Openair-Plasma pre-treatment of prismatic cells. Cleaning and activation lay the foundations for a precise adhesive bond with optimum
adhesive characteristics.

SAMPE JOURNAL

S E P T E M B E R /O C TO B E R 2 0 2 0

w w w. s a m p e . o r g

http://www.sampe.org

SAMPE Journal - September/October 2020

Table of Contents for the Digital Edition of SAMPE Journal - September/October 2020