FUCHS X LYDEN Joint Release: 700‑Day Operational Re‑inspection Report on Immersion‑Cooled Energy Storage Coolant
Recently, a CNAS‑accredited laboratory completed a full‑item re‑inspection of the immersion‑coolant deployed for the 30 MW frequency‑regulation project at Phase II of Haifeng Power Plant, with system integration undertaken by LYDEN New Energy.
Representing one of China’s large‑scale and early‑operational power‑plant‑based immersion‑cooled energy‑storage frequency‑regulation projects, the site uses FUCHS RENOLIN ES SUPER coolant. At the time of sampling, the fluid had been circulating continuously under full‑load conditions within battery enclosures for 700 consecutive days.
Re‑inspection findings confirm that RENOLIN ES SUPER shows no observable degradation in electrical insulation, chemical stability or thermal‑management performance, and maintains excellent material compatibility.
Robust Electrical Insulation: The Primary Safety Barrier Remains Intact
In immersion‑cooled systems, coolant directly wraps every single battery cell. Insulation failure would multiply safety risks. Reliable insulation is therefore the most critical long‑term verification metric for immersion‑cooled solutions and a top priority for LYDEN throughout the project lifecycle. Test results demonstrate that after 700 days of service, RENOLIN ES SUPER retains dependable electrical‑insulating properties, with dielectric loss and electrical conductivity remaining near instrument detection limits.
Outstanding Chemical Stability: No Degradation, No Corrosion Risks
Acid number and water content serve as core indicators for coolant degradation. A rising acid number signals potential corrosion, while excessive water content impairs demulsification performance. For system integrators focused on full‑lifecycle safety, these two parameters form key references for long‑term operation and maintenance. Re‑inspection data show both indicators remain at very low levels. The coolant preserves strong anti‑oxidation and anti‑demulsification performance with no risk of acid‑induced corrosion.
Consistent Thermophysical and Viscosity‑Temperature Properties: Stable Thermal‑Management Efficiency
Thickening coolant and impaired heat transfer can silently reduce system usable capacity and hurt plant revenue. For LYDEN, thermophysical and viscosity‑temperature characteristics are vital for evaluating full‑lifecycle project economics. Test results reveal viscosity‑temperature behavior, thermal conductivity and specific‑heat capacity largely match those of fresh fluid, so original system thermal‑management design parameters remain fully valid.
Favorable Material Compatibility and System Cleanliness
No corrosion risk was identified. The coolant is well‑compatible with metals and sealing materials; particle contamination stays under control. The fluid stays clear and transparent with no turbidity or phase separation. This verifies that internal components inside LYDEN‑integrated enclosures remain in sound condition after 700 days of operation.
As the system integrator, LYDEN has monitored the field performance of RENOLIN ES SUPER since commissioning. Its project leader commented:
“As an integrator, we attach great importance to full‑lifecycle safety and economics. Satisfactory re‑inspection results after long‑term full‑load operation greatly boost our confidence. Risks of system failures triggered by coolant degradation are extremely low, routine maintenance costs are optimized, and long‑term availability and return‑on‑investment are well‑secured. The exceptional long‑term stability of FUCHS products is key to our system’s sustained value creation.”
From 14‑month to 700‑day test cycles, successive datasets from the Haifeng Phase II project prove RENOLIN ES SUPER delivers sustained long‑term stability. Coolant no longer represents a recurring concern for energy‑storage systems. Maintaining steady insulation strength, chemical inertness and heat‑dissipation capability, it delivers verifiable evidence for long‑term safe operation, OPEX control and investment returns.
Selecting high‑quality FUCHS immersion‑coolant constitutes a strategic investment in energy‑storage system long‑term safety, stability and profitability. FUCHS will continue partnering with LYDEN and other industry stakeholders to advance deployment and high‑quality development of immersion liquid‑cooled energy‑storage technology.