Two TU Darmstadt start-ups on one of Europe’s most visible start-up stages
ILLUTHERM GmbH and reLi Energy have made it into the top 20 of the Slush 2025 pitch competition in Helsinki – and are now competing for a place in the final and a €1 million investment.
Slush, taking place on 19 and 20 November in Helsinki, is one of Europe’s largest and most influential start-up events: hundreds of start-ups meet investors, corporates and multipliers from all over the world. The international pitch competition therefore sends a strong signal to the market.
From over 100 applications to the top 20
ILLUTHERM and reLi Energy came through a multi-stage selection process against well over one hundred European applicants. After first being selected for the Top 100 and then the Top 50, they are now among the 20 start-ups pitching on stage on the first day of Slush – with a four-minute pitch and four-minute Q&A in front of an international expert audience.
Only three start-ups will then make it into the grand final on the second day of the conference – where a €1 million investment is at stake.
ILLUTHERM: Rethinking high-temperature processes
Founded in 2023 and based in Darmstadt, ILLUTHERM GmbH is developing a technology that uses blue LED light to heat materials such as steel to over 1,000 degrees Celsius within seconds.
The start-up is thus addressing a key lever for industrial decarbonisation: energy-intensive high-temperature processes. Its goal is to replace fossil fuels and make production processes in energy-intensive industries significantly more efficient and climate-friendly.
reLi Energy: Extending the lifetime of batteries and energy storage systems
Founded in 2022, reLi Energy GmbH optimises the operation of batteries and energy storage systems. By deploying intelligent operating strategies, the start-up extends storage lifetime, reduces costs and contributes to sustainability and resource conservation – a key factor for the energy transition.
Strong ecosystem – HIGHEST and Hessen visible together
Both teams are part of the Hessen delegation organised by Hessen Trade & Invest / StartHub Hessen, which is accompanying the start-ups at Slush. Alongside the competition, ILLUTHERM and reLi Energy are using Slush to build contacts with investors, industrial partners and other start-ups.
As HIGHEST – the Innovation and Start-up Center of TU Darmstadt – we are particularly pleased that two TU Darmstadt start-ups have made it this far in the Slush pitch competition. They are emblematic of the strength of our deep-tech start-up scene and of the close interplay between excellent research, technology transfer and entrepreneurship in Darmstadt and the Rhine-Main region.
We are keeping our fingers crossed for ILLUTHERM and reLi Energy to make it into the final – and to gain even more international visibility for their innovations and for our ecosystem.
Photo: Slush / Julius Konttinen