Big Battery 48V ETHOS 5.12kWh Stackable Battery Module

Name: Big Battery 48V ETHOS 5.12kWh Stackable Battery Module
Brand: Big Battery
SKU: FETHS-48051-G1
Price: 1250.0 USD
Availability: InStock

BY: Big Battery

SKU: FETHS-48051-G1

| Availability: In stock

$1,950.00

$1,250.00

You Save: $700.00

Product Highlights

Built for home backup and off-grid power
5,120 Wh capacity for extended backup and off-grid runtime
Purpose-built hardware secures compatible solar modules and racking
Expandable design lets stored power grow with future needs

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Big Battery 48V ETHOS 5.12kWh Stackable Battery Module

The BigBattery 48V ETHOS 5.12kWh Battery Module is the core of a scalable, stackable energy storage system—ideal for grid-tied homes, off-grid cabins, solar systems, and commercial setups. Each module features Tier 1 LiFePO4 cells (100Ah), a smart BMS with real-time monitoring, and is expandable up to 80kWh per system.

Engineered for safety and performance, it includes passive cell balancing, a fire-extinguishing module, and UL-certified ESS connectors. With a lifespan of 10+ years and 4,000–8,000 cycles at 80% DoD, it’s built to last.

The ETHOS system is IP65-rated, wall-mountable, and includes all necessary hardware for easy installation. Whether you're preparing for outages or building a complete solar setup, ETHOS delivers reliable, efficient power—on or off the grid.

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Features

Stackable Design – Expand your energy system with ease. The ETHOS allows you to stack multiple modules vertically for scalable power.

High-Capacity Storage – Each module delivers 5.12kWh of reliable energy—perfect for daily cycling, time-of-use offset, or emergency backup.

LiFePO4 Chemistry – Built with Lithium Iron Phosphate cells, known for their long cycle life, thermal stability, and safety.

Advanced BMS Built-In – Protects against overvoltage, short circuits, overcurrent, and temperature extremes for maximum system reliability.

UL Certified Safety – Includes UL1973 and UL9540A testing certifications, ensuring code compliance and peace of mind.

Modular Flexibility – Integrates with many 48V inverters, making it a great fit for custom and prebuilt energy systems.

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Applications

Residential Power Systems – Provides dependable energy storage for day-to-day household usage or grid-tied energy saving.
Home Solar Systems – Optimized for solar charging and discharge cycles, maximizing solar ROI.
UL-Certified ESS – Meets UL1973 and UL9540A standards, making it ideal for compliant energy storage systems.
Cabins & Tiny Homes – Compact and stackable, it's perfect for limited-space living environments.
Family Homes & Mansions – Easily stack multiple units to meet high-capacity energy demands.
Off-Grid Homesteads – Designed for long-term autonomy in fully off-grid living setups.
Emergency Power – Ready when the grid isn’t—perfect for natural disasters, outages, or backup readiness.
Whole Home Backup – Use multiple modules to power your entire home during blackouts.
Lead Acid Replacement – Upgrade from outdated lead-acid banks with safer, longer-lasting lithium technology.
Intense Heat & Cold – Built to perform in extreme climates with a wide operating temperature range.

What's Included

Everything you need is included with your product.

BigBattery 48V ETHOS 5.12kWh Battery Module

User Manual

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Specifications

Category	Specifications
SKU	FETHS-48051-G1
UPC	850061252067
System Voltage:	48V
Nominal Voltage:	51.2V
Chemistry:	LiFePO4
kWh Capacity:	5.12kWh
Ah Capacity:	100Ah
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
Max Continuous Discharge Current:	100A
Max Continuous Power:	5120W
Max Discharge Peak Current:	150A (Max 5 seconds)
Max Charge Current:	100A
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:	-4°F - 113°F (-20°C - 45°C) (Max 6 months)
Depth	6.7 in (170 mm)
Width	26.5 in (674 mm)
Height:	16.5 in (419 mm)
Max Connections:	Up to (16) parallel connections per control box
Protection Rating:	IP65
Communications:	CANBus / RS485
Certifications	UL9540a, UL1973, & UN38.3

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Videos

Frequently-Asked Questions

How many ETHOS batteries can I stack?

You can stack multiple modules based on your inverter’s configuration and your energy needs. For large systems, consult your installer to ensure proper BMS communication and power balancing.

Is this battery compatible with all 48V inverters?

It works with many major 48V inverter brands, but always confirm voltage, current, and communication protocol compatibility before integrating.

Does this battery support outdoor installation?

Yes. With its IP65 rating, the ETHOS is protected against dust and water spray, making it suitable for indoor or sheltered outdoor setups.

Is the BMS built-in or external?

Each module comes with an integrated Battery Management System that safeguards performance and extends battery life.

Manual and Specification Sheet

Shipping & Easy Returns

Shipping is free across the Lower 48. No fuel surcharges, no residential fees, and no liftgate charge on freight orders. The price you see is the price you pay. Read our full Shipping Policy here.

Most orders leave the warehouse in 1 to 2 business days and arrive within 3 to 10 business days. We send tracking the moment it ships.

Anything that ships on a pallet goes freight with liftgate and pallet jack included, so the driver gets it off the truck and onto the ground at your address. The carrier will call you directly to schedule a delivery window.

Returns are 30 days from delivery. For freight deliveries, inspect the shipment before you sign for it. If something is damaged in transit, note it on the delivery receipt and we handle the freight claim, not you. Read more about our Returns Policy here.

Why Buy From Us

Buying solar online should not mean guessing your way through the install. Here’s what you get with Off-Grid Source.

We size the system, not just sell it. Call before you order and a sales engineer will check the kit against your actual loads, tell you if you’re buying too much or too little, and list the site-specific parts your install will need.
A+ rated by the Better Business Bureau. Another trust signal that you’re buying from a real company that stands behind the sale.
Free shipping across the Lower 48. No hidden freight charges, residential fees, or liftgate surprises at checkout.
Guaranteed best prices. Find the same product for less elsewhere and we’ll match it.
30-day easy returns. If it is not the right fit, we’ll help you get it sent back.
A real person on the phone. Product questions, sizing, install planning, warranty help: call us at +1 (877) 556-3347.

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They Stood By Me

I was a DIY solar power wannabe... that is 'til I connected with Manny... The man's a prince! He not only knows his stuff; he walked me through all things electrical. To make sure I had all I needed... he gave me his cell phone # to text him anytime I got confused... nights and weekends included. The prices were very competitive... definitely go with Manny -- you won't go wrong!

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I am always hesitant to buy things at places I have never shopped... I want to give a shout out to Manny who with great patience and knowledge helped me get my orders... I felt valued as a customer and I will definitely be back in the future. I highly recommend them, they make you feel like family.

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I'm about to go off grid. I called Manny, he walked me through everything so I could truly understand what I needed and never tried to upsell me. He was honest and made a customer for life.

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Easy Return

I would personally like to thank Manny... I purchased the inverter and decided I needed to return it... Manny was very understanding and went out of his way to help me return the product and not even have to pay for shipping return. He gives this company reputation, honor and quality customer service!

Roger V.

Totally Off Grid.

I have been talking with Manny the owner... He has not only helped me design a system but he's been assisting with the install and components. I am super pleased so far with the assistance.

Jeff S.

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We added 2 more batteries to our current set up. Pleased with the customer service from Off-Grid Source! Will be back!

Jason

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Big Battery 48V ETHOS 5.12kWh Stackable Battery Module

Product Highlights

Big Battery 48V ETHOS 5.12kWh Stackable Battery Module

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Features

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Applications

What's Included

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Specifications

BigBattery 48V ETHOS 5.12kWh Stackable Battery Module Videos

Frequently-Asked Questions

Manual and Specification Sheet

Shipping & Easy Returns

Why Buy From Us

Why Choose Off Grid Source

Our Customers Tell It Better Than We Do

They Stood By Me

Awesome Service!

Real Person, Honest Service.

Easy Return

Totally Off Grid.

Great Product! Fast Shipping

Excellent Customer Service