As the global energy storage industry enters a phase of large-scale deployment, safety and compliance have become critical benchmarks in international technology competition. Recently, Kortrong Group's immersion liquid cooling technology received on-site validation at its Zhuhai headquarters with representatives from Électricité de France (EDF). Initial core tests have shown positive results, with further testing still underway.

 

Engineer representatives from EDF visited Kortrong's Zhuhai headquarters to observe and participate in a series of dedicated tests on the immersion-cooled energy storage system. The tests covered multiple dimensions including high and low temperature performance, cycle life, operating temperature gradient, and thermal runaway propagation – all aimed at evaluating the technology's performance under extreme conditions compared to conventional cooling solutions.

As the first company in the industry to achieve mass production of immersion-cooled energy storage systems, Kortrong has accumulated over 3GWh of deployed project experience globally. For this collaboration, Kortrong opened its rigorous, full‑lifecycle testing environment to the French side.

In the most critical test for safety evaluation – thermal runaway propagation – the testing team used a 52.25 kWh battery pack and induced thermal runaway in a single cell through continuous overcharging. The live demonstration showed: after the cell went into thermal runaway, no open flame was observed, and no thermal runaway spread to adjacent cells occurred.

An EDF egineer representative who participated in the testing commented:

"Placing safety at the forefront of energy storage R&D and operations is the fundamental principle behind EDF's collaboration with Kortrong on this test series. Such testing is essential to raising industry standards and strengthening confidence in innovative technologies. Based on our measured data, we observed that Kortrong's immersion technology effectively controlled the cell thermal runaway process, with the pressure relief valve temperature peaking around 90°C and no risk of propagation."

Kortrong engineers explained that this exceptional performance stems from the physical characteristics of full immersion: by completely submerging each cell in a circulating, non‑conductive, flame‑retardant cooling fluid, the system physically cuts off heat transfer and oxygen supply at the moment of a fault – breaking the chain reaction at its source.

Beyond the thermal runaway propagation test, a series of evaluations for long‑term operational reliability – including high/low temperature performance and cycle life – are also underway in parallel.

During technical exchanges, the French side expressed interest in Kortrong's progress on international compliance. Kortrong's 130 kW / 261 kWh immersion-cooled energy storage system has obtained CB and CE certifications from LCIE, a subsidiary of Bureau Veritas – making it the world's first immersion‑cooled storage product to pass the agency's testing. This marks a significant step in aligning Kortrong's compliance efforts with international standards.

This dedicated testing of the immersion-cooled energy storage system, observed and participated in by EDF, not only validates the maturity of Kortrong's immersion cooling technology but also establishes a technical foundation for deeper collaboration between the two parties – while providing a practical reference for the development of international energy storage safety standards.