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N O . 1 2 0 2 1 – S P E C I A L
For over 15 years, we have been
developing thermal, mechanical
and electrically-coupled simulation
models, parameter routines and full
processes – from initial requirements
to final test plans. This allows
us to repeatedly optimize new battery
generations with regard to performance,
durability and safety.
Our development work leverages
simulations and models. These integrated
CAE solutions are precisely
tailored to your needs, for example
with regard to accuracy or specific
standards (e.g. GTR, UNECE,
etc.). This guarantees the consistency
of our models in all phases – from
system design (AVL CRUISE™ M)
and construction via development
(electrochemical models in AVL
FIRE™ M, mechanical models in
Abaqus) to parameterization and
testing with tools such as our cell
testing device. By recreating real
phenomena in the simulation, we
are able to master even the toughest
cell development challenges.
MECHANICAL CELL TESTING
The Battery Safety Center is the result
of our long-term cooperation
with the Institute for Vehicle Safety
at Graz University of Technology.
The facility has sled systems for
moving batteries, as well as climatic
chambers, presses and specific stations
for simulating thermal propagation.
The tests we perform in
the Battery Safety Center are used
to parameterize models. These, in
turn, were developed as an R&D
project together with MIT. They are
among the most accurate models in
the world for battery cell deformation.
With our extensive mechanical
testing options, we are paving the
way for OEMs to fully integrate
cells and modules in vehicle chassis.
ELECTRICAL CYCLES AND
AGEING TESTS
For 20 years, AVL has also been developing
electrical battery and cell
testing equipment for automotive
development and fully-automated
tests. These integrated test systems
are fully regenerative, electrically
isolated and can reproduce dynamic
load changes that occur in reality
at any time. Thanks to the modular
structure, they can be flexibly
adapted to any requirements, offering
a high degree of future proofing.
For example, there are test chambers
capable of containing gas escapes up
to hazard level six. The cell brackets
are specifically designed for swelling
and breathing tests or electrochemical
impedance spectroscopy (EIS)
and can be adapted to all available
formats. The test stands are controlled
via a real-time automation
system. All the passive safety facilities,
such as overpressure valves and
rupture disks, also meet the highest
demands.
focus: In terms of their design, are
future high-energy cells safer than
the current generation?
Novak: New developments in chemistry
are towards greater safety with
higher energy density. However,
they can also have other durability
issues, as can be seen with all-
solid-state batteries (ASSB), and the
anodes which are very short-lived.
focus: Why are innovations in cell
formats and connections so important
for the automotive industry?
Novak: They offer potential for increased
efficiency. Optimal packaging
of the cells is extremely important,
particularly regarding swelling
and breathing – two phenomena
that occur in every battery. Safe
integration is crucial, particularly
with regard to the topic of rapid
charging.
Model prediction
High-resolution micro CT scanning
I N T E R V I EW
Wolfgang Novak
Skill Area Manager
Battery & Cell