The BigBattery NEXUS™ + EG4 12000XP ESS System is a powerful, scalable energy solution designed for both on-grid and off-grid applications. Combining high-capacity 15kWh NEXUS LiFePO? battery modules with the advanced EG4 12000XP hybrid inverter, this system delivers reliable, efficient energy for whole-home and commercial backup.
The EG4 12000XP provides up to 12,000W split-phase output per inverter with up to 24,000W PV input, enabling high solar production and seamless power management between solar, battery, and grid. With dual MPPTs, built-in breakers, and fast UPS switching (15–30ms), the system ensures uninterrupted power and optimized performance.
Expandable from 15kWh up to 225kWh and scalable up to 36kW output, the NEXUS battery system grows with your energy needs while delivering long-lasting, maintenance-free storage. Built with advanced battery protection, safe lithium technology, and U.S.-supported engineering, this system is ideal for residential, commercial, and off-grid energy independence.
- Ships From: Texas, USA
- Warranty: 12 Years (Battery), 5 Years (Inverter)
- Support: Lifetime USA-Based Tech Support
CompatibilityIntegrated & Optimized System - EG4 12000XP Hybrid Inverter + NEXUS 15kWh Battery Modules
Expandable Design - Scale battery storage from 15kWh up to 225kWh
- Supports multiple inverters up to 36kW system output
- Compatible with grid-tied, hybrid, and off-grid installations
- Key Features
- Complete ESS Solution – Battery + inverter system designed to work seamlessly together
- 12,000W Output per Inverter – Reliable split-phase power for residential and commercial systems
- 24,000W PV Input – High solar capacity with dual MPPT optimization
- 15kWh LiFePO? Battery Modules – Safe, high-capacity energy storage with long lifespan
- 6,000+ Cycle Life – Built for years of daily use and long-term savings
- UPS Backup (15–30ms) – Seamless transition during outages
- Smart Energy Management – Supports load control, AC coupling, and peak shaving
- Built-In Breakers & Safety Protections – Simplifies installation and enhances system safety
- Modular Expansion – Easily scale storage and output as energy needs grow
- Remote Monitoring & Control – Real-time system tracking and performance insights
- Maintenance-Free Operation – No routine servicing required
A high-capacity, scalable energy storage system built for performance, flexibility, and long-term energy independence – ideal for powering homes and businesses with confidence.Battery Specifications - Battery Specifications: NEXUS 15KWh
- System Voltage: 48V
- Nominal Voltage: 51.2V
- Chemistry: LiFePO4
- Usable Energy (kWh): 15kWh
- Ah Capacity: 300Ah
- Cell Configuration: 16S1P
- Max Continuous Discharge: 140A
- Max Discharge Power: 7.6kW
- Max Discharge Peak Current: 270A(1s)
- Max Charge Current: 140A
- Charging Voltage Range: 53.5V-57.6V
- Operating Voltage Range: 48V-57.6V
- Max Charge Voltage: 57.9V
- Suggested Low Voltage Cutoff50.8V
- Charge Temp Range: 32°F to 113°F
- Discharge Temp Range: -4°F to 113°F
- Optimal Discharge Temp: 59°F to 95°F
- Storage Temp Range (SoC >50%): (1 month: -4°F ~ 113°F | 3 months: -4°F ~ 95°F | 6 months: -4°F ~ 77°F)
- Humidity Range: 10%-95% (No Condensation)
- Weight (lbs): ~315 lbs
- Dimensions (WxHxD): 19.7 x 27.5 x 15.7 in (500×700×400 mm)
- Altitude Limit: <2000m
- Max Connections: 15 in parallel (up to 225kWh)
- Communications: RS485 / RJ45 / CAN
- Protection Rating: IP21
- Installation: Indoor Floor-standing
Inverter Specifications - Nominal AC Voltage: 120/240VAC | 120/208VAC (L1/L2/N required)
- Frequency (Grid | Generator): 60 Hz (Default) | 50 Hz (Configurable)
- Max Continuous AC Current (Grid | Generator): 100A @ 240VAC | 62.5A @ 240VAC
- Max AC Input Power: 24000W
- AC Bypass (Grid | Generator): 100A | 90A
- Recommended Generator Capacity: 6000W – 15000W
- Output Voltage: 120/240VAC | 208VAC
- Output Frequency: 60 Hz (Default) | 50 Hz (Configurable)
- Max Continuous Output Current: 50A @ 240VAC | 57.7A @ 208VAC
- Nominal Output Power (without PV): 12000W @ 240V | 12000W @ 208V
- Nominal Output Power (with PV): 12000W @ 240V | 12000W @ 208V
- Max Continuous Wattage: 12000W (L1/L2) | 6000W (L1-N/L2-N)
- Surge Capacity: 18000W (5 sec) | 15000W (10 sec)
- Power Factor: 0.99
- Total Harmonic Distortion: <3%
- Switching Time: <10 ms (Single) | <20 ms (Parallel)
- No. of MPPTs (Inputs per MPPT): 2 (2)
- Max Input Current: 35A / 35A
- Max Short Circuit Input Current: 44A / 44A
- DC Input Voltage Range: 100 – 480VDC
- Min Start Up Voltage: 100VDC
- MPPT Operating Voltage Range: 120 – 385VDC
- Nominal MPPT Voltage: 320VDC
- Max Utilized PV Power: 24000W (12000W per MPPT)
- Max Recommended PV Input: 28000W (14000W per MPPT)
- Efficiency: 99% (MPPT) | 93.5% (PV to Loads) | 92.8% (PV to Battery) | 92.5% (AC to Battery) | 90.2% (Battery to Loads)
- Idle Consumption (Standby Mode): <70W
- Nominal Voltage: 48VDC
- Battery Voltage Range: 46.4 – 60VDC
- Max Charge / Discharge Current: 250A
- Max Charge / Discharge Power: 12000W
- DC Cut-Off Voltage: 59VDC
- Recommended Battery Capacity per Inverter: >400Ah
- Max Parallel Connections: 6
- Protection Rating: IP20
- Communication Interface: RS485 / CANBus / WiFi
- Operating Temperature (Full Load): 32ºF – 113ºF (0ºC – 45ºC)
- Storage Temperature: 5ºF – 140ºF (-15ºC – 60ºC)
- Altitude: <6,561 ft (2000 m)
- Relative Humidity: 5 – 95% (Non-Condensing)
- Typical Noise Emission: <60 dB
- Cooling Method: Fan
- Weight: 104.7 lbs (47.5 kg)
- Depth: 5.9 in (150 mm)
- Width: 20.9 in (530 mm)
- Height: 34.25 in (870 mm)
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