Big Battery ETHOS 3x Expansion Kit Kits Big Battery

Big Battery ETHOS 3x Expansion Kit

Name: Big Battery ETHOS 3x Expansion Kit
Brand: Big Battery
SKU: K0699
Price: 3850.0 USD
Availability: InStock

BY: Big Battery

SKU: K0699

| Availability: In Stock

$4,430.00

$3,850.00

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Big Battery ETHOS 3x Expansion Kit

The Big Battery ETHOS 3x Expansion Kit is designed to enhance your existing ETHOS system by adding an additional 15.36kWh of lithium iron phosphate (LiFePO4) energy storage capacity. This all-in-one kit includes three 48V stackable battery modules, rack base, and necessary power and communication cables for seamless installation. Whether you're powering your home, business, or an off-grid setup, this expansion is built to deliver reliable, safe, and scalable energy.

BigBattery ETHOS 3x Expansion Kit Features

High-Capacity Storage

Expand your system with 15.36kWh of additional storage using three 5.12kWh LiFePO4 modules.

Compact Stackable Design

Space-saving form factor allows vertical stacking—ideal for tight utility rooms or garages.

Plug-and-Play Integration

Kit includes all parallel communication and power cables for fast setup with your existing ETHOS system.

Reliable LiFePO4 Chemistry

Safe, efficient, and long-lasting performance with lithium iron phosphate battery cells.

UL-Compliant Components

Components meet rigorous safety standards for home and commercial installations.

BigBattery ETHOS 3x Expansion Kit Applications

Residential Solar Storage - Store excess solar power for use at night or during grid outages, ensuring energy independence.
Commercial Power Backup - Keep critical systems running in small businesses during power interruptions and reduce downtime.
Off-Grid Living - Power remote homes or cabins with reliable energy storage that integrates with off-grid solar or wind systems.
EV Charging Energy Reserve - Use stored energy to support electric vehicle charging, reducing demand on the grid and saving costs.
Load Shifting & Peak Shaving - Lower energy bills by drawing from stored energy during peak utility rate hours.
Grid-Tied Battery Bank Expansion - Expand your existing on-grid battery setup for increased backup capacity or time-of-use optimization.

What's Included

Everything you need is included with your product.

3 × 48V ETHOS 5.12kWh Stackable Battery Module
1 × ETHOS RACK BASE

2 × Ethos Parallel Power Cable 4.9 ft (1500mm)
1 × Ethos Parallel Comm Cable 4.9 ft (150cm)

BigBattery ETHOS 3x Expansion Kit Specifications

Category	Specifications
SKU	KIT0699
GTIN-12 (U.P.C.)	850061252180
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
Cell Configuration	16S 3P
Max Continuous Discharge Current	250A
Max Continuous Power	10240W
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
Communications	CANBus / RS485

BigBattery ETHOS 3x Expansion Kit Video

Frequently-Asked Questions

Can I install this expansion kit without a Control Box?

No, this kit is an add-on and requires an existing ETHOS Control Box system.

How many modules can be added in total?

You can add up to 16 ETHOS modules (81.92kWh total) to a single Control Box.

Is the expansion kit user-installable?

Yes, with basic tools and knowledge. Still, professional installation is recommended for safety and warranty compliance.

Manual

BigBattery ETHOS 3x Expansion Kit Manual

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