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BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery

SKU: F-NXUS-48150-G1
Save $5,439.00 Save $809.00
Original price $4,039.99
Original price $4,039.99 - Original price $27,189.99
Original price $4,039.99
Current price $3,230.99
$3,230.99 - $21,750.99
Current price $3,230.99
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
Availability:
in stock, ready to be shipped
Availability:
in stock, ready to be shipped
Availability:
in stock, ready to be shipped
Quantity Options: 1 x Battery

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Product Highlights

Nexus is the most affordable 15kWh LiFePO₄ off-grid powerhouses with a portable, compact build, and scalability to 225kWh for unstoppable outdoor home or cabin backup power.

Key Features

  • Performance: Uninterrupted, long-lasting power for any off-grid application.
  • Chemistry: Advanced LiFePO4 for safety and longevity.
  • Design: Rugged, floor-standing design for easy installation in tech closets, garages, cabins, or sheds.
  • Protection: Integrated BMS with quadruple safety redundancies.
  • Scalability: High-capacity, expandable storage solution up to 225kWh.
  • Applications: Off-grid solar, commercial backup, and home EPS.

Whats included:
51.2V 300AH-15KWH Energy storage box, with fire extinguisher (aerosol) & heater

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BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery

BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery

Introducing the Nexus

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

PACKAGE INCLUDES

BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery

BigBattery NEXUS 51.2V 15kWH LiFePO4 Battery

x 1

Communication Cable

x 1

Power Cable (Red and Black)

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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