Low-voltage PV storage set: Deye SUN-8kW 3-phase hybrid inverter & Felicity FLS48100SG2 battery storage unit 10.24 kWh

Hybrid inverter and energy storage system as a set – the heart of your solar system

This set contains the two key components of a solar system with storage: the three-phase Deye SUN-8K-SG05LP3-EU-SM2 hybrid inverter and the Felicity FLS48100SG2 battery storage unit with a capacity of 10.24 kWh. Combine this set with solar panels of your choice to install a new system, or retrofit an existing PV system with this low-voltage PV storage set.
 

Who is this kit suitable for?

✅ Builders and homeowners who wish to select their own solar panels
✅ Owners of an existing PV system who wish to retrofit a storage system (AC coupling)
✅ Households with a three-phase domestic connection, as is common in Germany
✅ Households with higher consumption who wish to upgrade to up to 40.96 kWh at a later date
 

Components explained simply

1. Hybrid inverter: Deye SUN-8K-SG05LP3-EU-SM2

What it does: Solar panels generate direct current (DC), but your household needs alternating current (AC). The inverter converts the electricity. As a hybrid inverter, it also controls the storage system and automatically decides where the electricity flows: into the house, into the storage system or into the grid.

Why choose this inverter:

• 8 kW output, 3-phase: It feeds into all three phases of your domestic connection, as is standard practice in Germany.
• Unbalanced output: It can load the phases to different degrees, up to 50 % of the rated power (4 kW) per phase. This is useful because domestic appliances rarely use the phases evenly.
• Plenty of scope for solar modules: Up to 12.8 kW maximum PV input power, 800 V maximum input voltage and two MPP trackers. This also allows you to utilise two roof areas with different orientations, e.g. east and west.
• High efficiency: Up to 97.6 % (Euro efficiency 97.0 %).
• Retrofitting a storage system: The inverter can also be combined with an existing PV system via AC coupling.
• Smart charge control: With 6 freely adjustable time slots, you can specify when the storage unit is charged or discharged, e.g. to match a dynamic electricity tariff.
• Off-grid operation: According to the manufacturer, the inverter supports off-grid operation, i.e. operation without connection to the public grid. Whether and how your appliances will continue to be powered in the event of a power cut depends on the installation. Discuss this with your electrician.
• Future-proof: It supports charging via a diesel generator and the parallel operation of up to 10 inverters.
• Rugged: IP65 protection against dust and water jets, operating temperature range from −40 to +60 °C.
• Complies with standards: It complies with the German grid connection guideline VDE-AR-N 4105.

Integrated protection functions: Insulation monitoring, residual current detection, anti-islanding protection, DC switch, reverse polarity protection and overvoltage protection (Type II, DC and AC).

Good to know: The inverter weighs 35.2 kg and has a noise level of up to 55 dB. A utility room, utility cupboard, basement or garage is therefore a more suitable location than a living area.

2. Battery storage: Felicity FLS48100SG2 (10.24 kWh)

What it does: The storage unit stores surplus solar power and releases it as soon as the panels are not supplying enough, i.e. mainly in the evening and at night.

Why choose this storage system:

• 10.24 kWh capacity: Two modules, each with a capacity of 5.12 kWh. With a depth of discharge of at least 95 %, approximately 9.7 kWh is available.
• LiFePO4 cells: Lithium iron phosphate is considered a particularly safe and long-lasting battery chemistry. The storage system can around 6,000 charge cycles (at 0.2C, 25 °C and 80 % depth of discharge).
• Multiple layers of protection: An intelligent BMS, a circuit breaker and a fuse protect the storage unit. According to the manufacturer, this is supplemented by a fire protection module as well as protection against overcurrent, overvoltage, undervoltage and overtemperature. The fuse can be easily replaced from the outside.
• Easy to expand: The modules are stacked on top of one another. This allows you to expand the capacity up to 40.96 kWh (8 modules).
• Display: The control module displays the key values on an LCD screen; each battery module has an LED indicator.
• Charging and discharging capacity: With two modules, Felicity recommends 100 A (approx. 5.1 kW); a maximum of 120 A (approx. 6.1 kW) is possible under continuous operation. Adding more modules also increases the possible charging power.
• Warranty: 10 years (in accordance with Felicity’s warranty terms and conditions).

Important: The storage unit has an IP21 protection rating and must be installed indoors, e.g. in the cellar, utility room or garage. It is placed or stacked on the floor, it is not designed for wall mounting. Each module weighs approx. 46 kg (approx. 92 kg in total) and measures 600 × 450 × 180 mm. Charging is possible at 0–55 °C, and discharging at −20–55 °C.

Scope of delivery

• 1x Deye SUN-8K-SG05LP3-EU-SM2 hybrid inverter (3-phase)
• 1x Felicity FLS48100SG2 battery storage system 10.24 kWh, comprising 1x control module FLS48100SCG2 and 1x battery module FLS48100SMG2

FAQs on the low-voltage PV storage set

Which solar modules are compatible with the inverter?
The inverter handles up to 12.8 kW of PV input power via two solar inputs, each with one string. The voltage range is 200–650 V, with a maximum current of 20 A per input. This means it is compatible with most modern solar modules. Your installer will determine the exact wiring configuration.

Can I combine the kit with my existing PV system?
Yes. The inverter supports AC coupling. This allows an existing PV system to be retrofitted with a storage unit without replacing the existing inverter. Your electrician will advise you whether this is suitable for your system.

How much energy can I actually store?
The battery has a rated capacity of 10.24 kWh. With a depth of discharge of at least 95 %, you’ll have around 9.7 kWh of usable energy available.

How quickly does the storage unit charge and discharge?
With two modules, Felicity recommends a current of 100 A, which is around 5.1 kW. A maximum of 120 A (around 6.1 kW) is possible on a continuous basis, depending on temperature and state of charge. As the number of storage modules increases, so does the possible charging and discharging power.

Can I expand the storage system later?
Yes. The FLS48100SG2 can be expanded to accommodate up to 8 modules, which equates to 40.96 kWh. The modules are simply stacked on top of one another.

Can the storage unit be wall-mounted?
No. The storage unit is placed on the floor or stacked. It has an IP21 protection rating and must be located indoors, e.g. in the cellar, utility room or garage.

Where is the inverter installed?
The inverter is IP65-rated and can also be operated in harsh environments. With a noise level of up to 55 dB, a utility room, cellar or garage is more suitable than a living space.

Will the system work during a power cut?
According to the manufacturer, the inverter supports off-grid operation (stand-alone mode). Whether your appliances will continue to be powered in the event of a power cut depends on the installation. Seek advice from your electrician on this matter.

What does ‘low voltage’ mean and what are the advantages?
The battery operates at a nominal voltage of 51.2 V (48 V class). Low-voltage systems are considered particularly safe to use and can be easily expanded in a modular fashion.

What warranties apply?
The Felicity battery comes with a 10-year warranty in accordance with Felicity Solar’s warranty terms and conditions. The Deye inverter comes with a 5-year warranty in accordance with Deye’s warranty terms and conditions.

Can I install the system myself?
Connection to the domestic mains supply and commissioning must be carried out by a registered electrician. Furthermore, the system must be registered with the grid operator and in the market master data register.