Freen-BSL-N Energy Storage

The Freen-BSL-N is a low-voltage, modular sodium-ion battery system built on NFPP chemistry (sodium iron phosphate pyrophosphate), the most durable and safest cathode material available in sodium-ion technology. Designed for residential, small commercial, and public-tender applications where maximum cycle life and zero critical minerals are non-negotiable.

Engineered as a 50 V floor-mounted unit, Freen-BSL-N integrates with standard hybrid and off-grid inverters via CAN and RS485, making it a direct fit for solar, wind, and hybrid renewable systems. Its modular design has no parallel limit, so capacity grows with your needs without architectural constraints.

Key Benefits

NFPP: The Safest Sodium-Ion Chemistry

NFPP cathode material has less than 4% crystal lattice volume change during cycling, virtually eliminating particle degradation. No oxygen release at high charge voltage. No thermal runaway under any abuse condition: short circuit, puncture, overcharge, or crush.

14,000 Full Cycles

The highest cycle life in the Freen lineup. At one cycle per day, that is over 38 years of operation. Energy retention ≥60% at end of life. The battery will outlast the building.

Zero Critical Minerals

NFPP chemistry uses only iron and sodium. No lithium, no cobalt, no nickel in the entire cell. Closes the critical-minerals question on any EU public tender without additional documentation.

High Energy Efficiency

Round-trip efficiency above 97%, ensuring minimal losses during charging and discharging.

Wide Temperature Tolerance

Discharge from -30°C to +60°C without external heating. Charge from 0°C to +55°C. Full performance in Nordic winters, mountain cabins, and unheated outbuildings where lithium batteries shut down or waste stored energy on self-heating.

Unlimited Parallel Scalability

Each unit provides 7.5 kWh. The number of modules in a system is limited only by the inverter, not by the battery. No artificial ceiling on capacity.

Lightest in the Floor-Mount Line

108.6 kg per module, 11% lighter than the standard BSL. Easier to carry through a doorway, down a staircase, or into a garage.

Technical Highlights

• Nominal Voltage: 50 V
• Voltage Range: 40–60 V
• Usable Energy (per unit): 7.5 kWh
• Capacity: 150 Ah
• Max Continuous Power: 4 kW
• Max Current: 80 A
• Cycle Life: >14,000 cycles to 60% SOH
• Efficiency: >97%
• Cooling: Natural convection (no fans, no pumps, no filters)
• Installation: Indoor, floor-mounted
• Communication: CAN & RS485 for inverter integration
• Ingress Protection: IP20
• Weight: 108.6 kg
• Certifications: CE, UN38.3, IEC 62619

Smart Battery Management

An advanced integrated BMS continuously monitors cell voltage, current, and temperature. It provides:

• Over-charge / over-discharge protection
• Short-circuit and over-current protection
• Active cell balancing
• Automatic shutdown under unsafe conditions
• Real-time communication with compatible inverters via CAN protocol
• Remote monitoring included at no extra cost

Ideal For

✔ Home solar and wind energy storage

✔ Farms, off-grid cabins, and remote properties

✔ EU public tenders requiring zero critical minerals

✔ Projects demanding maximum cycle life (telecom sites, daily-cycling installations)

✔ Cold-climate installations without heated enclosures

✔ Backup power and self-consumption optimization

Warranty

Backed by a 10-year warranty with guaranteed energy throughput (MWh) over the warranty period. If the battery underperforms versus the warranted throughput, we replace it. Not a marketing promise, a contractual commitment.