Chinese manufacturer Hithium has recently signed a strategic cooperation framework agreement with KNESS Group, an international renewable energy and energy solutions provider, in Warsaw, Poland. Under the agreement, the two companies will focus on the Ukrainian market, advancing energy storage projects with a total planned capacity of 2 GWh over the next two years.
The cooperation will cover multiple BESS of varying durations, including 6.25 MWh and 5 MWh systems, with approximately 400 MWh scheduled for initial delivery in Q1 2026.
Sam Wang, Sales Director of Hithium, emphasized that long-duration energy storage is becoming critical infrastructure for supporting high renewable energy penetration and enhancing power system resilience in Ukraine.
Hithium sees growing demand for long-duration energy storage in Eastern Europe, driven by the accelerated deployment of renewables. In September 2025, the company signed a 2 GWh battery energy storage supply agreement with Bulgarian EPC Solarpro Holding. This deal will support multiple utility-scale energy storage projects across Eastern Europe, including Bulgaria, Hungary, Romania, and North Macedonia.
As part of this agreement, Hithium will supply its long-duration DC block solutions, including the ∞Power 6.25 MWh BESS using 1175 Ah and 587 Ah battery cells.
Notably, Hithium was among the first BESS suppliers active in Bulgaria, having delivered a 25 MW / 55 MWh battery storage facility for Austria’s Renalfa IPP in 2024 – then the largest operating system of its kind in the country.
The latest supply deal announcement follows the release of Hithium’s results from a large-scale fire safety test of its 6.25 MWh ∞Power battery energy storage system. The so-called open-door test, supervised by UL Solutions, subjected the unit to maximum oxygen conditions to evaluate thermal runaway risks in high-capacity 1175 Ah cells. Hithium reported that fire-resistant module covers, reinforced steel enclosures, and insulated multi-layer container structures confined any fire to a single battery system, with no thermal propagation across containers and temperatures in adjacent cells remaining below safety thresholds.
Ranked among the top DC BESS suppliers and frequently appearing in the top three DC-side rankings alongside CATL and BYD, Hithium is also a leading battery cell manufacturer. According to the latest data from Taiwanese research firm InfoLink, Hithium was the second-largest battery cell supplier worldwide in 2025, surpassed only by CATL.
