
Big Battery | 12kW | 30.7kWh | ETHOS Energy Storage System (ESS)
12kW | 30.7kWh | ETHOS Energy Storage System (ESS)
Premium Indoor Power Storage for Homes, Cabins & Tiny Living
BigBattery's 48V ETHOS Energy Storage System delivers a robust 30.7kWh indoor solution, perfectly tailored for grid-tied residential setups, including tiny homes, cabins, and family residences. With reliable performance, intelligent energy management, and industry-leading safety features, the ETHOS is engineered to power your lifestyle while maximizing energy savings.
Built for Flexibility & Growth
The ETHOS system is designed with a stackable, modular format that grows with your energy needs. It comes pre-equipped with everything you need for a smooth installation—no guesswork required.
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Indoor-Optimized Configuration: Clean, compact, and designed for interior spaces
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Expandable Design: Scale up as your energy demands increase
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Easy Installation: Includes all mounting and integration hardware
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Durable Protection: IP65-rated enclosure shields against dust and water intrusion
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Internal Fire Suppression: Safety you can trust in residential environments
Intelligent Monitoring & Control
An intuitive LED control panel and integrated CANBus + RS485 protocols offer real-time diagnostics and performance visibility.
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Smart Monitoring: LED interface provides system status at a glance
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Advanced Battery Management System (BMS): Auto cell-balancing ensures optimal battery life and performance
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Reliable Safety Mechanisms: Continuous monitoring helps prevent faults or imbalance
Paired with a Powerful 12000W Lux Inverter
To complete the system, the ETHOS is paired with a high-efficiency 12kW Lux inverter, delivering the power and smart control capabilities needed for hybrid grid and off-grid setups.
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Three MPPT Inputs: Maximize PV input from multiple solar arrays
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18000W PV Array Support: Handles large-scale solar production
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Integrated UPS Module: Seamless transitions between grid and backup power
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LCD Touchscreen Display: Simplified control and configuration
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Smart Load Control, AC Coupling, & Peak Shaving: Optimize usage, reduce utility costs, and maintain system stability
Key Features Summary:
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30.7kWh Indoor Battery Storage – Ideal for homes with medium to high power needs
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12kW Output via Lux Inverter – Efficient power for whole-home loads
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Expandable & Modular – Adaptable for future energy upgrades
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Advanced Safety – IP65 protection, auto-balancing BMS, fire suppression
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Real-Time System Monitoring – Built-in LED control and advanced communications
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High Solar Input Capacity – Supports up to 18,000W of PV panels
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Seamless On/Off-Grid Switching – Integrated UPS ensures uninterrupted power supply
Get Reliable, Scalable Power with the 48V ETHOS Indoor ESS
The 12kW | 30.7kWh ETHOS Energy Storage System (ESS) is a smart investment for homeowners seeking dependable, scalable, and safe indoor energy storage. Whether you're preparing for emergencies, optimizing solar usage, or qualifying for net metering and solar incentives, the ETHOS delivers.
Take control of your home’s energy and reduce your reliance on the grid with ETHOS—built for today, ready for tomorrow.
What's Included
6 × 48V ETHOS 5.12kWh Stackable Battery Module
1 × ETHOS Control Box
1 × ETHOS RACK BASE
1 × LUXPower 12kW Hybrid Inverter
2 × Ethos Parallel Power Cable 4.9 ft (1500mm)
1 × Ethos Parallel Comm Cable 4.9 ft (150cm)
Specs and Downloads
SKU: | K0957 |
GTIN-12 (U.P.C.): | 850061252128 |
System Voltage: | 48V |
Nominal Voltage: | 51.2V |
Chemistry: | LiFePO4 |
kWh Capacity: | 15.36kWh |
Ah Capacity: | 300Ah |
Charging Voltage Range: | 55.6 - 57V |
Max Charge Voltage: | 57V |
Operating Voltage Range: | 48 – 57V |
Suggested Low Voltage Cutoff: | 48 – 50.8V |
BMS Cutoff Range: | 42 - 47V |
Cell Configuration: | 16S 3P |
Max Continuous Discharge Current: | 250A |
Max Continuous Power: | 12800W |
Max Discharge Peak Current: | 300A (Max 5 seconds) |
Max Charge Current: | 200A |
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) |
Weight: | 387 lb (175.5 kg) |
Depth: | 6.7 in (170 mm) |
Width: | 26.5 in (674 mm) |
Height: | 59.8 in (1520 mm) |
Max Connections: | Up to (16) parallel connections per control box |
Protection Rating: | IP65 / NEMA 4X |
Communications: | CANBus / RS485 |
Certifications: | UL9540, UL9540A, UL1973, & UN38.3 |
User Manual
UL9540 Certification
UL1973 Certification
Safety Data Sheet
Inverter
User Manual
Rapid ShutDown Certificate
UL1741 Certificate
IEEE1547 Certificate
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Do We Accept Returns?
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Are Products Brand New?
Yes! All products on Solar Guys Pro are 100% brand-new and in perfect condition.
We do not sell any used or refurbished items.

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Frequently Asked Questions

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