BigBattery ETHOS 3X Expansion Kit | 3 × 48V 5.12kWh LiFePO4 Batteries
BigBattery ETHOS 3X Expansion Kit | 3 × 48V 5.12kWh LiFePO4 Batteries
SKU: K0699
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- Price: $3,279.50
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- List Price: $4,040.00
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- Price: $3,279.50
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PRODUCT DESCRIPTION
Description
BigBattery ETHOS 3X Expansion Kit | 3 × 48V 5.12kWh LiFePO4 Batteries



Product Description
The BigBattery ETHOS 3X Expansion Kit adds three 48V 5.12kWh stackable battery modules to an ETHOS energy storage system. The kit includes an ETHOS rack base and the parallel power and communication cables needed to integrate the additional modules.
Built for system expansion, this kit provides greater energy-storage capacity and flexibility while retaining the modular ETHOS design.
- Includes three 48V 5.12kWh ETHOS battery modules
- Stackable design supports ETHOS system expansion
- LiFePO4 battery chemistry
- Includes an ETHOS rack base
- Includes parallel power and communication cables
- IP65 and NEMA 4X protection ratings
- CANBus and RS485 communication
- Backed by BigBattery’s 12-year warranty

Specifications
| Specification | Details |
|---|---|
| SKU | K0699 |
| Battery Quantity | 3 modules |
| Capacity Per Module | 5.12kWh |
| System Voltage | 48V |
| Nominal Voltage | 51.2V |
| Battery Chemistry | LiFePO4 |
| Charging Voltage Range | 55.6–57V |
| Maximum Charge Voltage | 57V |
| Operating Voltage Range | 48–57V |
| Suggested Low-Voltage Cutoff | 48–50.8V |
| BMS Cutoff Range | 42–47V |
| Charge Temperature Range | 32°F to 113°F / 0°C to 45°C |
| Discharge Temperature Range | -4°F to 140°F / -20°C to 60°C |
| Optimal Discharge Temperature Range | 59°F to 95°F / 15°C to 35°C |
| Storage Temperature Range Above 50% SOC | -4°F to 113°F / -20°C to 45°C for up to 6 months |
| Maximum Connections | Up to 16 parallel connections per control box |
| Protection Rating | IP65 / NEMA 4X |
| Communication | CANBus / RS485 |
| Certifications | UL9540A, UL1973 and UN38.3 |
| Kit Weight | 420 lb |
| Warranty | 12 years |
What's In The Box?
- 3 × 48V ETHOS 5.12kWh Stackable Battery Modules — FETHS-48051-G1
- 1 × ETHOS Rack Base — CNT081
- 1 × ETHOS Parallel Power Cable, 4.9 ft — CBL089
- 1 × ETHOS Parallel Communication Cable, 4.9 ft — CBL096
FAQs
How many battery modules are included?
The kit includes three 48V ETHOS 5.12kWh stackable battery modules.
Is this a complete standalone ETHOS system?
The product is listed as an expansion kit intended to add battery modules to an ETHOS energy storage system.
Does the kit include an ETHOS control box?
No ETHOS control box is listed among the included components.
Are the parallel connection cables included?
Yes. The kit includes one 4.9-foot parallel power cable and one 4.9-foot parallel communication cable.
What warranty covers the batteries?
BigBattery backs the batteries with a 12-year warranty.
