The PY.FLEX DC is built for teams that design their own systems and bring their own power conversion, topology and controls. What the block brings is a sodium-ion core they can specify around: a wide thermal operating window, reduced thermal runaway risk, and liquid cooling that holds cell temperature even when conditions do not cooperate. Specified to drop into an architecture that has already been drawn.
Built into your system
Systems you design yourself
Your inverters, your topology, your controls, specified by the team that owns the design.
Where the battery has to fit the design
The architecture is set before the battery is chosen, so the block has to work within decisions that are already made.
Open by design, robust by chemistry
Sodium-ion safety and liquid cooling, supplied as a block for you to integrate.
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Ready when you are
Your power conversion, your call
Supplied without an inverter, so the topology stays yours
Open integration
Fits into existing DC architectures without rework
Proven safety
Reduced thermal runaway risk
Stable under pressure
Reliable across a wide range of ambient temperatures
Built tough
Engineered for demanding environments
Grow on demand
Capacity can be added step by step
Independent by supply chain
Built without lithium and without cobalt
PY.FLEX DC
A sodium-ion battery energy storage system, supplied as a DC block without a power conversion system. Nothing bundled, nothing assumed.
Built for where power matters
Self-Consumption Optimization
Backup Power
Independent Power Supply / DC Remote Microgrids
Low Voltage Grid Support
Energy Arbitrage
DC EV Charging Infrastructure – Overnight & Grid Support
Peak Shaving
Keep reading
PHENOGY in the Press: Resilient Energy for Armed Forces
Sodium-ion battery storage makes energy supply more resilient: robust in operation and at extreme temperatures, independent of vulnerable supply chains. The military benefits too: in our contribution to the "Future of Defence" supplement, we explain why the technology is ready for the field. The supplement was published in September 2026 in the Frankfurter Allgemeine Zeitung, one of Germany's leading national newspapers (in German).
‘This Award Shows That We Are on the Right Track’
The market is moving in a direction for which PHENOGY is well positioned.
7 Reasons PHENOGY Became the First Sodium-Ion Winner
Sustainable, Safe, and Proven in Practice
Disclaimer: Layout and specifications are subject to change as part of our continuous improvement process.
Use cases: Supported when integrated with your power conversion and controls.
Energy Arbitrage: Our battery storage enables arbitrage by storing low-cost or self-generated electricity and using it when market prices are high, helping to optimize costs and reduce CO2 emissions, while enabling additional value through energy trading.
External Communication / Aggregator: Communication with external systems or commercial aggregators is handled by the power conversion unit selected for the project. The PY.FLEX DC is supplied without power conversion, so these interfaces are defined on the customer side.
EMS: Not included. Energy management is provided by the customer-side system.
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