Fortress Power eFlex 5.4kW Lithium Deep Cycle Solar Battery - ShopSolar.com

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SKU EFLEX-5.4

by Fortress Power

Fortress Power eFlex 5.4kW Lithium Deep Cycle Solar Battery

Name: Fortress Power eFlex 5.4kW Lithium Deep Cycle Solar Battery
Brand: Fortress Power
Price: 2583.0 USD
Availability: InStock

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Fortress Power eFlex 5.4kW Lithium Deep Cycle Solar Battery

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In Stock Get yours today!

11+ sold In the last 7 days

Free Returns Free Returns within 30 Days of Purchase

Lifetime Customer Support Unlimited lifetime support, always available.

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Why Choose Shop Solar

Limited Supply. Order Yours Today!

Quite possibly the most well made battery on the market, the eFlex 5.4 kWh lithium battery from Fortress Power comes with built-in wifi for remote monitoring and troubleshooting to compliment its 10 year warranty with the safe and premium prismatic Lithium-Iron-Phosphate cells. It's expandable from 5.4 kWh to 81 kWh for whatever your application needs making this one of the most popular units in the Fortress line-up.

WATERPROOF AND SALTWATER RESISTANT

The aluminum cabinet that houses the high quality battery cells is IP 65 waterproof which will prevent salt water corrosion.

Specifications:

Total Energy: 5.376 kWh
Nominal Voltage: 51.2(48)V
Voltage Range: 45-58.4 V
Max. Charge Current(Continuous): 100 Amp
Max. Discharge Current(Continuous): 100 Amp
Recommend Storage temperature: 32 to 95 F
Charge temperature: 32 to 113 F
Capacity: 105 Amp-hour
Dimension(H x W x D): 7.2" x 17.5" x 21.5"
Weight: 116 lbs

Lowest cost per cycle!

High ound trip efficiency & >99% mixed with 6000+ lifecycles means that this is one of the best bangs for your buck when it comes to a lithium deep cycle battery.

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Features:

High Durability and long-lasting: 10 Year Warranty with the safe and premium prismatic Lithium-Iron-Phosphate cells

Versatile Applications: Expandable from 5.4 kWh to 81 kWh for residential, commercial, railway, military and telecommunications applications

Lowest Cost Per Cycle: High energy throughout with exceptional life span (6000+ cycles) and hight round-trip efficiency (>99%)

Monitor from Anywhere: The battery has a built-in data storage Wi-Fi for remote monitoring and troubleshooting ability

Waterproof and saltwater resistant: The sleek-looking aluminum cabinet has IP65 waterproof rating to prevent salt-water corrosion

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Are Compatible with most inverters!

The eFlex5.4 is compatible with most inverters on the market today, but customers have found the best pairing with the units below:

- Sol Ark

- Outback Radian Series

- Schneider Conext

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Compatible Inverters

Fortress Lithium Iron Phosphate batteries are designed to work with most 48VDC inverter and chargers available on the market. Below is a list of compatible inverters and chargers.

Sol-Ark: - AC or DC coupled

- 8 KW & 12 KW Inverters

Schneider: - AC or DC coupled

- Conext XW MPPT charge controller; Conext XW+/XW pro series

Outback: - AC or DC coupled

- Skybox, FLEX max charge controller (48V), FLEXpower series (48V); Radian series (48V); FXR(A) and FXR (E) series (48V); GVFX and GVFX series (48V);

Magnum: - AC or DC coupled

- MS 4448PAE; MS 4048-20B

SMA: - AC coupled

- SUNNY ISLAND 4548-US/6048-US; SUNNY ISLAND 3.0M/4.4M/6.0H/8.0H

Victron: - DC coupled

- Phoenix VE.Direct Inverter; MultiPlus and Quatro Inverter/Charger; Skylla-TG Charger; General; Color Control or Venus GX

Morning Star: - DC coupled

- TriStar MPPT 600V; TriStar MPPT; Tristar PWM

Midnite Solar: - DC coupled

- Solar Classic 150, 200 & 250; Solar Classic 150, 200 & 250-SL

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Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

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Top Solar Company in the USA

The prestigious ranking by Consumer Affairs is based on comprehensive evaluations, including ratings and reviews, equipment options, support services, pricing transparency, warranties, and various other factors. Among the top 6 nominated companies, Shop Solar stands out with the highest review rating, reaffirming its dedication to customer satisfaction and product quality.

Best Components, Lowest Prices

We cut out the bloat of traditional solar companies and pass those savings off to you. Plus, lifetime customer service on everything we sell.

Expert Guidance

Our team of solar professionals is here to help you navigate the world of solar with ease. From selecting the perfect solar kit to installation and beyond, we provide support and expertise at every step of the journey.

We’re people just like you

We’re not corporate and neither are our customers. We’re just a group of 50+ solar enthusiasts who are passionate about providing an honest, no-BS way for anyone, anywhere to improve their lives and the world around them with solar power.

Trusted Solar Authority

With over 40,000+ happy customers, 2,500+ positive reviews, and decades of experience in the industry, we’re proud to say we’re America’s #1 solar power solutions provider. You can trust us to provide you with top-notch products and legendary customer service at every step of the way.

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Troy P

EG4 off-grid base kit, Happy with my purchase.

This is the first stage of my three planned purches. I got the eg4 inverter 6000 XP base kit with six 400 watt panels and the two server rack batteries. Did a little online research and followed the instructions and it got set up without any issues. Right now I'm just running it in my garage on a single outlet and have been running dual 750 watt water distillers with it. Once I get the second inverter and a bunch more panels and batteries, I plan on attaching it to my subpanel in my house that has my lights and outlets and appliances on it. Then I'll get a soft start for my AC and blower and run it on my main panel.

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Trying to pick the correct solar system for your needs can be very technical and frustrating. I wanted to thank Yvhan and the Shop Solar team for their patience and helpful attitudes through multiple calls. I feel like we were able to narrow it down to what worked for me and my family. My system works great and I couldn't be happier to have picked Shop Solar.

PB

Patrick B

Off Grid Solar Purchase

I wanted to get an offgrid solar system for years but didn’t know where to start. I found Shop Solar on Facebook and decided to submit a quote. Within 24 hours I had a custom proposal that was almost half the price of the companies I had previously got quotes from. My wife and I decided to order online and the kit came in a timely manner and it was an easy install. Great company to work with!

JM

James Martin

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I would like to take the time to express the outstanding service that I was provided with by Shop Solar. They provided me with all the answers to my questions, and after reviewing our quote over the phone I felt comfortable proceeding to order my kit. It’s exactly what I needed and they were there to help us over the phone when we had questions installing it. I highly recommend others in need to choose Shop Solar Kits.

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Brian H

Solar Kit for Mobile Work Van

As a professional videographer, I needed reliable power on the go. ShopSolar's Delta Pro and roof-mounted panels were the perfect solution. Setup was easy, and the kit included everything needed. The Delta Pro powers my cameras, lights, laptop, and a small fridge with impressive battery capacity.

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You folks have been wonderful guiding me through the ins and outs of going solar. Plus your tech guys Rod and Nelson are the absolute best. They explained all the different aspects of inverters, batteries and how to keep them in top condition. Too much more to put here… but no other company has the 100% tech support you provide for your customers!

CA

Coll A

Great Experience

My experience with Shop Solar has been excellent. Before the sales, they answered all my questions to assure that I got what I needed. After the sales they continued to support me with answers and help. I had a warranty issue with a unit, and it was handled as well as possible. I would recommend them to anyone looking to go solar.

TP

Troy P

EG4 off-grid base kit, Happy with my purchase.

This is the first stage of my three planned purches. I got the eg4 inverter 6000 XP base kit with six 400 watt panels and the two server rack batteries. Did a little online research and followed the instructions and it got set up without any issues. Right now I'm just running it in my garage on a single outlet and have been running dual 750 watt water distillers with it. Once I get the second inverter and a bunch more panels and batteries, I plan on attaching it to my subpanel in my house that has my lights and outlets and appliances on it. Then I'll get a soft start for my AC and blower and run it on my main panel.

JB

Jacob B

Easy Process, Genuine Support

Trying to pick the correct solar system for your needs can be very technical and frustrating. I wanted to thank Yvhan and the Shop Solar team for their patience and helpful attitudes through multiple calls. I feel like we were able to narrow it down to what worked for me and my family. My system works great and I couldn't be happier to have picked Shop Solar.

PB

Patrick B

Off Grid Solar Purchase

I wanted to get an offgrid solar system for years but didn’t know where to start. I found Shop Solar on Facebook and decided to submit a quote. Within 24 hours I had a custom proposal that was almost half the price of the companies I had previously got quotes from. My wife and I decided to order online and the kit came in a timely manner and it was an easy install. Great company to work with!

JM

James Martin

Highly Recommend

I would like to take the time to express the outstanding service that I was provided with by Shop Solar. They provided me with all the answers to my questions, and after reviewing our quote over the phone I felt comfortable proceeding to order my kit. It’s exactly what I needed and they were there to help us over the phone when we had questions installing it. I highly recommend others in need to choose Shop Solar Kits.

BH

Brian H

Solar Kit for Mobile Work Van

As a professional videographer, I needed reliable power on the go. ShopSolar's Delta Pro and roof-mounted panels were the perfect solution. Setup was easy, and the kit included everything needed. The Delta Pro powers my cameras, lights, laptop, and a small fridge with impressive battery capacity.

KS

Keith S

Best Tech Support

You folks have been wonderful guiding me through the ins and outs of going solar. Plus your tech guys Rod and Nelson are the absolute best. They explained all the different aspects of inverters, batteries and how to keep them in top condition. Too much more to put here… but no other company has the 100% tech support you provide for your customers!

CA

Coll A

Great Experience

My experience with Shop Solar has been excellent. Before the sales, they answered all my questions to assure that I got what I needed. After the sales they continued to support me with answers and help. I had a warranty issue with a unit, and it was handled as well as possible. I would recommend them to anyone looking to go solar.

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Fortress Power eFlex 5.4kW Lithium Deep Cycle Solar Battery

*Limited Supply. Order Yours Today!*

WATERPROOF AND SALTWATER RESISTANT

Specifications:

Lowest cost per cycle!

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Features:

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Are Compatible with most inverters!

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Compatible Inverters

Sol-Ark: - AC or DC coupled

Schneider: - AC or DC coupled

Outback: - AC or DC coupled

Magnum: - AC or DC coupled

SMA: - AC coupled

Victron: - DC coupled

Morning Star: - DC coupled

Midnite Solar: - DC coupled

*In Stock & Ready To Ship! Limited Supply. Order Yours Today!*

Still have questions? Give us a call at 877-242-2792

What is your return policy?

What’s covered by your return policy?

How long will it take to receive my order?

What are your financing and payment options?

How does your Lifetime Customer Support work?

Top Solar Company in the USA

Best Components, Lowest Prices

Expert Guidance

We’re people just like you

Trusted Solar Authority

Prepare for Anything

Solar Power Made Easy

Secure Your Independence

Solar That Makes Sense - DIY+

Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

Why Choose Shop Solar

What To Expect - Complete Kits

Top Solar Company in the USA

Best Components, Lowest Prices

Expert Guidance

We’re people just like you

Trusted Solar Authority

What to Expect - Solar Panels

What to Expect - Batteries

Go Solar Now, Pay Later

Quick and Easy Application

Poor Credit or No Credit?

No Money Down Today

How we compare to the others!

Customer Success Stories

EG4 off-grid base kit, Happy with my purchase.

Easy Process, Genuine Support

Off Grid Solar Purchase

Highly Recommend

Solar Kit for Mobile Work Van

Best Tech Support

Great Experience

EG4 off-grid base kit, Happy with my purchase.

Easy Process, Genuine Support

Off Grid Solar Purchase

Highly Recommend

Solar Kit for Mobile Work Van

Best Tech Support

Great Experience

Shop Securely, Trusted Supplier, 100% Satisfaction

Trusted Company, Real Products, Lifetime Support

Avoid Scams, Buy with Confidence, Enjoy Peace of Mind

Manufacturer Warranty, Exceptional Service

Shop Securely, Trusted Supplier, 100% Satisfaction

Trusted Company, Real Products, Lifetime Support

Avoid Scams, Buy with Confidence, Enjoy Peace of Mind

Manufacturer Warranty, Exceptional Service

Be Smart, Buy From an Authorized Dealer

SOLAR + STORAGE MINI COURSE

Limited Supply. Order Yours Today!

In Stock & Ready To Ship! Limited Supply. Order Yours Today!