Pylontech Fidus Battery EU Pro FB-L-5.12-EU-Pro 5.12kWh5.12kWh 51.2V self-heating LFP battery, without brackets and cables

Overview

The FB-L-5.12-EU-Pro is the self-heating version of the Fidus Battery EU: 5.12kWh at 51.2V, 4.86kWh usable, 100A continuous and up to 200A for 15 seconds. Cell-level heating works between -20°C and -10°C, so the battery can be placed in unheated garages or sheltered outdoor spots where winter temperatures fall below the standard model's -10°C limit. This listing is the battery alone, without mounting brackets or cables, which suits installers who already stock Pylontech accessories or rack mounting. Two units give 10.24kWh, six give 30.72kWh.

• 5.12kWh, 51.2V LiFePO4, 4.86kWh usable
• 100A continuous, up to 200A for 15 seconds
• IP65 enclosure with C5-M corrosion protection
• Pro version with cell-level self-heating
• Up to 20 batteries per group, 6 groups
• LED, Bluetooth and optional Wi-Fi

How it works

Fidus Battery EU is a 51.2V lithium iron phosphate battery with an integrated BMS, sized at 5.12kWh nominal and 4.86kWh usable at 95% depth of discharge. Units connect in parallel: up to 20 batteries form one group and up to six groups can be combined, which Pylontech puts at 5–583kWh. Multi-group systems need the LV-HUB-V2 as master, with at most 19 batteries per group.

Two versions share housing and electrical data. The FB-L-5.12-EU works from -10°C to +55°C. The FB-L-5.12-EU-Pro adds cell-level heating that activates between -20°C and -10°C, so the battery can bring itself into its working range in unheated rooms; charging and discharging are allowed only above -10°C.

Key features

Each battery delivers 100A continuous in both directions, 103–120A for two minutes and 121–200A for 15 seconds, which equals 1C continuous and 2C peak. Pylontech states 8,000 cycles at 25°C, 0.5C and 5–95% state of charge, plus a 15-year design life. The IP65 enclosure carries C5-M corrosion protection and natural cooling, and the battery is certified to IEC 62619, IEC 63056, VDE-AR-E 2510-50 and IEC 62477-1.

Installation and compatibility

Pylontech designs Fidus for wall, ground or rack mounting, indoors or in sheltered outdoor locations within -10°C to +55°C, or -20°C for the Pro. A unit measures 630×170×363mm and weighs 45kg. Discharge voltage runs from 42.5V to 56.8V and charge voltage from 56V to 56.8V, so the inverter must support a 48V-class LFP battery with CAN or RS485 battery communication.

Fidus appears in Pylontech's low-voltage compatibility list, which Pylontech says covers more than 50 inverter brands. Listed models include Victron MultiPlus and Quattro 48V via Venus OS, SMA Sunny Island 4.4M, 6.0H and 8.0H, Studer Xtender and Next3, Schneider Conext XW Pro and Solis S6-EH1P-L single-phase hybrids, each with notes on firmware and settings.

Monitoring and settings

The integrated BMS communicates with the inverter over CAN or RS485, and Pylontech's compatibility list states for each inverter whether communication, force-charge activation and firmware versions have been verified. LED indicators and Bluetooth are built in for on-site checks, and Wi-Fi is available as an option for remote monitoring. Short-circuit current is limited to less than 1000A for 1ms, which helps when sizing fuses and breakers between battery and inverter.

Questions and answers