Automotive Engineering - April 2023 - 35

Chamber
made to
PROTECT
EV BATTERIES
With the ACS Dust Chamber, testing
to ISO 20653 helps ensure EV
battery housing designs will keep
out dust and small particulates.
I
ngress protection testing against solid particulates, such as dust,
is a crucial part of battery manufacturing. If a battery is not designed
to keep dust out, small particles can infiltrate and wreak
havoc on the delicate workings within the battery's housing.
A major vehicle OEM selected ACS, a specialized equipment maker,
to design and build a self-contained test stand with a dust chamber,
in accordance with ISO and client-specific standards. ISO 20653 testing
determines the degrees of protection provided by enclosures of
electrical equipment on road vehicles against foreign objects, water,
and access. This test stand was designed to test the 5K and 6K regimes
of ISO 20653. Among the client-specific requirements was the
ability to test two different size batteries in a single chamber.
ACS engineered and built an environmental test chamber designed
to the standard of keeping 2 kg (4.4 lb) of dust suspended per cubic
meter of volume. After exposure in the dust chamber, the battery can
be examined to see how much, if any, dust made it inside. The dust is
circulated to a specific mass per unit volume and flow rate using a
fan that was modified for this application.
The entire test stand is dust-tight, preventing it from creating a
mess in the plant. Its footprint uses 8 x 8 ft (2.4 x 2.4 m) of floor
space, stands 7 ft (2.1 m) tall and weighs less than 4000 lb (1814 kg).
The unit can easily be moved and has a minimal power draw, requiring
only 480V at 60A to operate.
The interior working volume was designed for a test article up to
50 cubic ft (1416 L). The geometry of the test chamber was critically
sized for the specific devices under test. The volume of the test
chamber was optimized to allow adequate airflow around the largest
test article as well as minimize excess space for a test article with a
smaller volumetric footprint.
By knowing the test article constraints, the ACS team was able to
right-size the fan and keep the ISO dust on-hand to a minimum. An
Allen-Bradley PLC on the unit allows the operator to control the duAUTOMOTIVE
ENGINEERING
EV BATTERY TESTING FEATURE
The ACS Dust Chamber's interior working volume was designed
for a test article up to 50 cu.ft. The geometry of the chamber was
critically sized for the specific devices under test.
" Small particles can
infiltrate and wreak
havoc on the delicate
workings within the
battery's housing. "
ration and speed of the suspended air-dust mixture.
The automaker is now able to test degrees of protection
against foreign objects, determining whether
its batteries provide 5K ingress protection (dust-protected)
or 6K ingress protection (dust-tight).
" One of the technical challenges with this project
was to design the chamber and size the test stand for
multiple battery sizes, " said David Suehs, engineering
manager, Machine Design Group at ACS. " The ISO
standard requires a 2 kilogram mass of dust per cubic
meter. As the unoccupied volume interior to the
chamber changes with the test article, the fan velocity
and volume of raw dust product needed to be varied, "
he noted.
Based in Verona, Wisconsin, ACS designs, engineers,
and builds innovative equipment, machines, controls,
and facilities for industry leaders in verticals including
automotive, aerospace, and manufacturing. ACS has a
regional office in Troy, Michigan, and serves customers
across North America and around the world. For more
information: acscm.com.
April 2023 35
http://www.acscm.com
Automotive Engineering - April 2023

Table of Contents for the Digital Edition of Automotive Engineering - April 2023
