AVL Focus - Issue 2025

The Innovation: AEE 1

In 2024, AVL took a decisive step: with its first proprietary

PEM electrolyzer stack – designated AEE 1 – a new level

of technology excellence was established. Developed,

manufactured, and tested entirely in-house within only twelve

months, the stack stands out not only for its efficiency, but

also for several technological features that set it apart from

existing solutions:

• Differential pressure operation: AEE 1 operates reliably at

30 bar. This reduces the need for additional compressors

and simplifies direct integration into industrial processes.

• Optimized water and gas management: Uniform

distribution across all cells ensures low pressure losses

and minimizes degradation – critical for long service life.

• Material and design innovations: Tailored bipolar plates

and catalyst layers enhance robustness and enable high

current densities, even under dynamic operation with

renewable energy sources.

Development Process and Core Competencies

The stack architecture builds on AVL’s profound understanding

of hydrogen technology and its long-standing experience

with automotive fuel cell stacks. Proven principles from

high-volume manufacturing – such as precise sealing

concepts and minimized contact resistance – were directly

transferred to the electrolyzer design. Another decisive factor

was AVL’s methodology of safeguarding designs through

virtual simulation and co-simulation with Digital Twins,

which shortened iteration loops significantly, while ensuring

maximum precision and quality.

Customer Benefits and Market Impact

The benefits for customers are clear: AEE 1 enables reduced

development costs and shorter time to market. Beyond

providing the technology, AVL supports customers with

simulation, testing, and training. A current example is a

project with a Chinese partner to develop a 2.5 MW stack

based on the AEE 1 design, demonstrating that the solution is

immediately transferable to industrial scale.

With its first PEM stack developed in-house, AVL underscores

its innovative strength in energy technology. AEE 1 exemplifies

how expertise from the automotive industry can be

successfully applied to the challenges of the energy transition.

It represents AVL’s commitment to actively shaping the path to

a climate-neutral future.

AEE 1 PEM

­Electrolyzer Stack

• Developed in just 12 months

• Efficiency: 71 % (LHV) > exceed-

ing DOE 2026 target (69 %)

• Energy consumption:

47 kWh/kg H2

• Operation at 30 bar differential

pressure

• Active cell area: 300 cm²

• Foundation: automotive fuel cell

engineering know-how

• Reference project: 2.5 MW PEM

stack with Chinese partner in

development

“The AEE 1 is a

technological

breakthrough for

scalable, efficient

PEM electrolysis,

marking AVL’s entry

into industrial stack

development.”

JÜRGEN RECHBERGER

Head of Business Unit Fuel Cell & Energy

2025