Freen-BSL-T Smart Telecom Battery

The Freen-BSL-T is a smart 48 V sodium-ion backup battery built for telecom sites, base stations and any unmanned installation where power has to hold and nobody is there to fix it. It uses the same Na-ion chemistry (NFPP) as the rest of the BSL range, so it brings the same thermal stability and long service life without lithium, and adds a bidirectional DC/DC converter that lets it work alongside the batteries already on site.

Engineered as a rack-embedded unit for standard telecom cabinets, the BSL-T drops into an existing shelter without rebuilding the power plant. It runs in parallel with legacy VRLA or lithium strings, so a site can be modernised one battery at a time instead of all at once.

Key Benefits

Works With the Batteries You Already Have

A self-developed bidirectional DC/DC converter offers three selectable modes: battery pass-through, boost/buck and smart hybrid. Mixed strings of VRLA, lithium and sodium can share one busbar, which removes the biggest cost from a site upgrade.

True Arctic Operation

Stable operation from −40 °C to +60 °C with 85 % discharge efficiency retained. Northern, mountain and desert sites need no cabinet heating, which means no parasitic load and one less thing to fail.

Extended Reach on Existing Feeders

Boost mode raises and holds a constant bus voltage, extending remote power capability over cable that is already in the ground. Constant-voltage discharge defaults to 52 V and is adjustable across 42 to 58.4 V.

Built-In Theft Protection

An integrated gyroscope plus software-based anti-theft system. On unguarded sites this is often the argument that closes the deal.

Long Service Life

Over 10,000 cycles at 70 % DOD, with a 20-year design life, roughly double that of a conventional lithium backup battery.

Modular and Scalable

Each unit delivers 4.8 kWh, and up to 32 units run in parallel for 153.6 kWh on a single 48 V bus.

Technical Highlights

• Nominal Voltage: 48 V
• Bus Operating Range: 42 to 58.4 V
• Energy (per unit): 4.8 kWh
• Capacity: 160 Ah cell, NFPP prismatic
• Max Discharge Power: 4,800 W at the bus
• Charge / Discharge Current: 100 A / 100 A
• Discharge Cut-off: 40 V
• Parallel Operation: up to 32 units, 153.6 kWh
• Cooling: Natural convection, no fans
• Installation: Embedded, telecom cabinet
• Dimensions: 480 × 550 × 200 mm
• Weight: 46 kg
• Ingress Protection: IP45
• Altitude: up to 4,000 m
• Certification: CE, UL 1642, UN 38.3, CB, MSDS

Smart Battery Management

An advanced integrated BMS monitors cell voltage, current and temperature continuously, and speaks to the site through a genuinely broad interface set: CAN, two RS485 ports, three dry contacts, IoT and TCP. It provides:

• Over-voltage and under-voltage protection
• Short-circuit and overload protection
• Reverse-polarity protection
• Over-temperature and low-temperature protection
• Compatibility with mainstream DC controllers and power systems
• Remote monitoring and firmware management

Ideal For

✔ Telecom base stations and shelters

✔ Unmanned and hard-to-reach sites

✔ Retrofit alongside existing VRLA or lithium banks

✔ Off-grid repeaters, sensors and monitoring stations

✔ Extending remote power over existing feeders

Warranty

Backed by a long-term performance warranty with guaranteed retained capacity over time.