BigBattery ETHOS 3X Expansion Kit 48V 15.36kWh LiFePO4 Battery | K0699
BigBattery ETHOS 3X Expansion Kit 48V 15.36kWh LiFePO4 Battery | K0699
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- Price: $3,279.50
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PRODUCT DESCRIPTION
Description
BigBattery ETHOS 3X Expansion Kit 48V 15.36kWh LiFePO4 Battery | K0699

Product Description
The BigBattery ETHOS 3X Expansion Kit is designed to add three additional ETHOS battery modules to an existing ETHOS energy storage system. This modular expansion provides greater energy storage capacity and runtime while maintaining seamless integration with the existing system.
Built around 48V LiFePO4 battery technology, the ETHOS expansion system provides scalable energy storage with integrated battery management, CANBus/RS485 communications, and an IP65 / NEMA 4X protection rating.
Key Benefits
- Adds three ETHOS battery modules to an existing system
- Expands ETHOS energy storage capacity
- 48V LiFePO4 battery technology
- Modular design for expanding an existing ETHOS installation
- CANBus / RS485 communications
- IP65 / NEMA 4X protection rating
- Supports up to 16 parallel connections per control box
- UL9540A, UL1973 and UN38.3 certifications
- Backed by BigBattery's 12-year warranty



Specifications
| Specification | ETHOS 3X Expansion Kit |
|---|---|
| SKU | K0699 |
| Configuration | 3× ETHOS Battery Modules |
| System Voltage | 48V |
| Nominal Voltage | 51.2V |
| Battery Chemistry | LiFePO4 |
| Total Capacity | 15.36kWh |
| Total Ah Capacity | 300Ah |
| 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 |
| Cell Configuration | 16S 3P |
| Maximum Continuous Discharge Current | 300A |
| Maximum Continuous Power | 15,360W |
| Maximum Discharge Peak Current | 450A, max. 5 seconds |
| Maximum Charge Current | 300A |
| Charge Temperature Range | 32°F–113°F (0°C–45°C) |
| Discharge Temperature Range | -4°F–140°F (-20°C–60°C) |
| Optimal Discharge Temperature Range | 59°F–95°F (15°C–35°C) |
| Storage Temperature Range (SoC >50%) | -4°F–113°F (-20°C–45°C), max. 6 months |
| Maximum Connections | Up to 16 parallel connections per control box |
| Protection Rating | IP65 / NEMA 4X |
| Communications | CANBus / RS485 |
| Certifications | UL9540A, UL1973 & UN38.3 |
| Warranty | 12 Years |
What's In The Box?
- 3× BigBattery ETHOS battery modules
FAQs
Q: What is the BigBattery ETHOS 3X Expansion Kit designed for?
A: It is designed to add three additional ETHOS battery modules to an existing ETHOS energy storage system.
Q: How much capacity does the three-module configuration provide?
A: Three ETHOS battery modules provide 15.36kWh of energy storage capacity and 300Ah capacity.
Q: What battery chemistry does the ETHOS use?
A: The ETHOS uses LiFePO4 battery chemistry.
Q: Can multiple ETHOS batteries be connected together?
A: Yes. The system supports up to 16 parallel connections per control box.
Q: What communication protocols does the ETHOS system support?
A: The ETHOS system supports CANBus and RS485 communications.
Variant Specs
| Variant | SKU | Battery Modules | Capacity |
|---|---|---|---|
| ETHOS 2X Expansion Kit | K0698 | 2 | 10.24kWh |
| ETHOS 3X Expansion Kit | K0699 | 3 | 15.36kWh |
