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BigBattery NEXUS 51.2V 15kWh LiFePO4 Battery + EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter Kit

SKU: K0152
Save $3,452.50 Save $1,130.00
Original price $5,650.00
Original price $5,650.00 - Original price $17,262.50
Original price $5,650.00
Current price $4,520.00
$4,520.00 - $13,810.00
Current price $4,520.00
Availability:
in stock, ready to be shipped
Availability:
in stock, ready to be shipped
Availability:
in stock, ready to be shipped
Availability:
in stock, ready to be shipped
Availability:
in stock, ready to be shipped
Bundle Options: 1 x NEXUS Battery + EG4 6000XP Inverter

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Product Highlights

NEXUS LiFePO₄ modules (15kWh each) pair with the EG4 6000XP delivering 6,000W split-phase per inverter and up to 8,000W PV input, perfect for grid-tied or off-grid backup; systems scale from 15kWh to 225kWh and up to 18kW output. Featuring dual MPPTs, built-in breakers, a 15–30ms UPS transfer switch, and remote monitoring, they ensure seamless and efficient performance. Lightweight and transformer-free, they support smart load control, AC coupling, and peak shaving to reduce energy costs while providing reliable backup power.

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BigBattery NEXUS 51.2V 15kWh LiFePO4 Battery + EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter Kit

BigBattery NEXUS 51.2V 15kWh LiFePO4 Battery + EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter Kit

Introducing the Nexus

Legacy Product Parallel Compatibility

The NEXUS is compatible and parallel-able with all existing KONG and GRIZ products purchased between 2019-2024.

 

Specifications:

BigBattery NEXUS 51.2V 15kWh LiFePO4 Battery
System Voltage 48V
Nominal Voltage 51.2V
Chemistry LiFePO4
Usable Energy (kWh) 15kWh
Ah Capacity 300Ah
Cell Configuration 16S1P
Max Continuous Discharge 100A
Max Discharge Power 7.6kW
Max Discharge Peak 110A
Max Charge Current 100A
Charging Voltage Range 53.5V-57.6V
Operating Voltage Range 48V-57.6V
Max Charge Voltage 57.9V
Suggested Low Voltage Cutoff 50.8V
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%) -4°F ~ 77°F
Humidity Range 10%-95% (No Condensation)
Weight (kg) ~142.8 kg ±5
Dimensions (WxHxD) 19.7 in x 27.5 in x 15.7 in
Altitude Limit <2000m
Max Connections 15 in parallel (up to 225kWh)
Communications RS485 / RJ45 / CAN
Protection Rating IP21
Certifications UN38.3
Installation Indoor Floor-standing
EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter
AC INPUT
AC Voltage 120V AC / 240V AC
AC Frequency 50 Hz / 60 Hz
Max. Continuous AC Current 37.5A @ 240V
Max. AC Input Power 9000W
AC Bypass 50A
AC OUTPUT
Output Voltage 120V AC / 240V AC
Output Frequency 50 Hz / 60 Hz
Max. Continuous Output Current 25A @ 240V
Output Power 6000W
Surge Capacity 12000W (3.5 sec) / 11000W (5 sec)
Power Factor 0.99 (Full Load)
Reactive Power Adjustment Range -0.8 - 0.8 Leading Adjustable
Total Harmonic Distortion <3%
Switching Time <15 ms (Single) / <30 ms (Parallel)
PV INPUT
No. of MPPTs (Inputs per MPPT) 2 (1)
Max. Input Current 17A / 17A
Max. Short Circuit Input Current 25A / 25A
DC Input Voltage Range 100 - 480V DC
Start Up Voltage 100V DC ± 10V DC
MPPT Operating Voltage Range 120 - 385V DC
MPPT Voltage 320V DC
Max. PV Array Power 8000W (4000W per MPPT)
MPPT Efficiency 99%
BATTERY
Nominal Voltage 48V DC
Battery Voltage Range 46.4 - 60V DC
Max. Discharge Current 140A
Max. Charge Current 125A
DC Cut-Off Voltage 59V DC
DC Recovery Voltage 57.4V DC
Charge Cut-Off Voltage 58.4V DC
OPERATING ENVIRONMENT
Operating Temperature 32ºF - 113ºF
Storage Temperature 5ºF - 140ºF
Altitude <6,561 ft (2000 m)
Relative Humidity 5 - 95%
Typical Noise Emission <58 dB
Protection Rating IP20
Max. Parallel Connections 16
DIMENSIONS
Weight 52.9 lbs
Depth 5.25 in
Width 18 in
Height 25.5 in

PACKAGE INCLUDES

BigBattery NEXUS 51.2V 15kWh LiFePO4 Battery + EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter

BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery

x 1

EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter

x 1

User Manual

x 1

Frequently Asked Questions

How do I connect this battery into my existing system?

These batteries use a standard M8 terminal. This battery can be connected directly to the onboard wiring system. You may also purchase additional cables from BigBattery.

How many times can I put this battery in parallel/series?

These batteries are not series capable but can be connected in parallel up to ten times. Make sure that the total amount of these batteries in your configuration never exceeds 15 total batteries. When connecting batteries in parallel, ensure all batteries are within 1 volt of one another.

How long will my battery last, and what do I do at the end of its life?

Lithium iron phosphate (LiFePO4) batteries can be cycled from 3500 - 5000 times. If you cycle the battery daily then you can get more than 12 years of use from your battery. When your battery is at the end of its lifespan, contact us and we'll recycle it for you, free of charge!

Product Documents:

BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery User Manual

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BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery Specification Sheet

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EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter Specification Sheet

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EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter User Manual

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EG4 6000XP 6000W 48V Split Phase Off-Grid Inverter Certification Of Compliance

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OTP graphic
OTP graphic