Sunsynk G5.3 5.32kWh 51.2V LiFePO₄ Battery for Solar and Backup Power

The Sunsynk G5.3 is a low-voltage lithium iron phosphate (LiFePO₄) battery designed for modern solar
energy storage and backup power systems where safety, longevity, and system scalability are critical.
With a nominal voltage of 51.2V and an energy capacity of 5.32kWh, the G5.3 is engineered to operate
reliably in daily cycling applications as well as during grid power interruptions.

This battery is not a generic lithium storage unit. It is purpose-built to integrate with compatible
hybrid and inverter-charger systems using CAN2.0 and RS485 communication, allowing the inverter to
receive real-time battery data and apply controlled charge and discharge behavior.

Sunsynk G5.3 battery system role and operating concept

In a solar-and-storage system, the Sunsynk G5.3 functions as a managed energy storage module rather than
a passive DC power source. Its internal battery management system continuously monitors voltage,
current, temperature, and state of charge, ensuring the battery operates within safe limits under all
conditions.

This enables stable operation during solar charging, inverter discharge under load, and transition
periods during grid outages. When paired with a compatible inverter, the battery becomes an active
participant in system control rather than a standalone component.

Low-voltage architecture and scalability

The G5.3 operates as a 48V-class (51.2V nominal) battery, making it suitable for a wide range of
low-voltage hybrid inverters and inverter-chargers. One of its key strengths is scalability, with
support for parallel connection of up to 32 battery units, allowing total system capacity to exceed
170kWh.

This makes the Sunsynk G5.3 suitable not only for residential installations but also for larger
commercial systems where extended backup duration or higher sustained loads are required.

Charge and discharge capability

The battery is designed to handle meaningful charge and discharge currents, supporting a recommended
current of 50A, a maximum continuous current of 100A, and short-duration peak currents up to 150A.
This allows the system to support real-world load behavior, including momentary surges from pumps,
motors, or appliances when the system is correctly designed and protected.

Cycle life and daily use durability

Built on lithium iron phosphate cell chemistry, the G5.3 prioritizes safety and long service life.
Under typical operating conditions, the battery is rated for a cycle life of 6000 cycles at 90% depth
of discharge, making it suitable for daily charge-and-discharge operation over many years.

The recommended depth of discharge of 90% balances usable energy with long-term durability, ensuring
consistent performance across the battery’s service life.

Installation format and physical design

The Sunsynk G5.3 is designed for wall-mounted installation and also supports integration into
19-inch standard battery cabinets. The enclosure is intended for indoor installation where the
battery is protected from direct environmental exposure.

Clear LED indicators on the front panel provide immediate visual feedback on state of charge and
operating status, which is useful during commissioning and troubleshooting.

Communication and system integration

CAN2.0 and RS485 communication ports allow the battery to integrate with compatible inverters and
energy management systems. This enables controlled charging, accurate state-of-charge reporting,
and coordinated protection behavior between the battery and inverter.

This communication-based approach improves system stability compared to voltage-only battery setups.

Technical specifications

Identity

• Brand: Sunsynk
• Model: SUNSYNK-G5.3
• Battery type: Low-voltage lithium battery module

Battery and electrical

• Battery chemistry: Lithium iron phosphate (LiFePO₄)
• Nominal voltage: 51.2 V
• Operating voltage range: 43.2 – 57.6 V
• Capacity: 104 Ah
• Nominal energy: 5.32 kWh
• Usable energy: 4.79 kWh
• Recommended depth of discharge: 90%

Charge and discharge

• Recommended current: 50 A
• Maximum continuous current: 100 A
• Peak current (2 minutes at 25°C): 150 A

Scalability and communication

• Parallel capability: Up to 32 units
• Total scalable capacity: Up to approximately 170 kWh
• Communication ports: CAN2.0, RS485

Physical

• Dimensions (W × H × D): 440 × 600 × 133.2 mm
• Weight: 44 kg
• Installation method: Wall-mounted or 19-inch cabinet supported
• Ingress protection rating: IP20

Environmental

• Charge temperature range: 0°C to +55°C (optional heating allows operation down to -20°C)
• Discharge temperature range: -20°C to +55°C
• Storage temperature: -20°C to +35°C
• Humidity: 5% – 95%
• Maximum altitude: ≤2000 m

Certifications

• CE
• UK
• UN38.3