Fronius LFP: 6.3kWh [HV Battery]

The Fronius Reserva is a DC-coupled high-voltage modular Lithium Iron Phosphate (LFP) battery system designed for residential solar energy storage. Built around 3.15 kWh modules operating at a nominal 102.4 V each, the Reserva 6.3 uses 2 stacked modules to deliver 6.31 kWh of 100% usable energy. With 5.94 kW continuous charge/discharge power, an 8.45 kW 5-second peak, a 10-year warranty with 70% capacity retention in Australia, backup power capability, and full Fronius Solar.web monitoring, the Reserva 6.3 is a capable and well-integrated entry-level storage solution for Australian homes. Designed exclusively to pair with Fronius GEN24 Plus and Verto Plus hybrid inverters, it delivers a true single-manufacturer ecosystem for inverter, battery, monitoring, and support.

Fronius LFP 3.15 DataSheet

Fronius LFP 3.15 User Manual

Fronius LFP 3.15 Warranty

Key Benefits

Premium Performance for High-Demand Homes

The Fronius Reserva 6.3 connects directly to the DC bus of the Fronius GEN24 Plus hybrid inverter, charging the battery from the PV array without requiring an intermediate AC conversion step. This DC coupling approach minimises energy losses during charging, making the most of even brief windows of solar generation throughout the day. The combination of 5.94 kW continuous power with an 8.45 kW 5-second peak provides sufficient output for most residential demand events — from air conditioner startup currents to simultaneous operation of multiple large appliances. The system can also draw charge from the grid at off-peak tariffs, managed through the Fronius Solar.web platform.

Advanced LFP Architecture at Scale

The Reserva uses Lithium Iron Phosphate (LFP) prismatic cells — widely recognised as the safest and most thermally stable lithium chemistry for residential battery storage. Unlike NMC chemistries, LFP cells have a significantly higher thermal runaway threshold, supporting safer installation in habitable structures and garages. Each module operates at a nominal 102.4 V with a capacity of 30.85 Ah (~3.16 kWh). The 2-module Reserva 6.3 produces a nominal system voltage of 204.8 V, operating across a range of 185.6–227.2 V — fully compatible with Fronius GEN24 Plus single-phase and selected three-phase hybrid inverter platforms. An integrated Battery Management System (BMS) provides continuous multi-layer protection against over-voltage, under-voltage, over-current, and thermal events, along with automatic forced re-charging to prevent deep discharge.

Designed for Expansion and Long-Term Value

The Reserva 6.3 is the entry-level configuration of the Fronius Reserva range. The same tower can be expanded up to 5 modules — providing 9.5, 12.6, or 15.8 kWh — by adding modules to the existing stack and BMS without replacing the base unit. For larger storage requirements, up to four Reserva towers can be connected in parallel without additional combiner boxes or third-party hardware, allowing total system capacity of up to 63.2 kWh. Importantly, adding parallel towers increases capacity only — it does not increase charge/discharge power. This makes the Reserva 6.3 a sensible entry point for homeowners who may wish to expand as their usage grows, without committing to a platform change.

Technical Specifications

Energy Storage Specifications

Power Specifications

Physical & Environmental Specifications

System Integration

Warranty & Performance

Compatibility Table

The Sungrow SBH High Voltage Battery is primarily designed for Sungrow three-phase hybrid inverters:

Installation & Requirements

What's Included

Installation Prerequisites

Certifications & Compliance

AS/NZS 5139 Compliance Positioning

Important: Product features and certifications support compliant installation outcomes, however final AS/NZS 5139 compliance is site-specific and must be confirmed by the installer based on battery location, mounting surface, clearances, barriers, ventilation, and the overall system design.