EcoFlow DeltaPro 3 Extra Battery Pack really allowed my system to shine. Before I was depleting my system. Now, I’m able to keep up with my loads and use solar to keep it charged. I can't be any happier. - Michael C.

EcoFlow DELTA Pro 3 Smart Extra Battery

Name: EcoFlow DELTA Pro 3 Smart Extra Battery
Brand: EcoFlow
SKU: EFDELTAPRO3EB
Price: 1899.0 USD
Availability: OutOfStock

by EcoFlow

SKU: EFDELTAPRO3EB

Sold out

$2,599.00

$1,899.00

St. Patrick's Day Power Sale!

Limited-Time Offers End March 24

Select Number of Batteries

1 x Battery

2 x Batteries

Availability: Out of stock

Quantity

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Send us a request and we'll beat it today. Guaranteed!

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Double Down On Power And Freedom With The DELTA Pro 3 Smart Extra Battery

Experience true energy independence with the EcoFlow DELTA Pro 3 and the DELTA Pro 3 Smart Extra Battery. This cutting-edge expansion battery seamlessly integrates with your DELTA Pro 3, doubling its capacity to a mighty 8kWh. Add a second battery and reach a sky-high 12kWh of super power.

Imagine powering your essential appliances, electronics, and even medical devices for extended periods during outages, off-grid adventures, or worksites lacking reliable electricity.

What's Included

1 x EcoFlow DELTA Pro 3 Smart Extra Battery
1 x EcoFlow Extra Battery Cable
1 x Quick-Start Guide
1 x Safety Guide
1 x Warranty Card

EcoFlow DELTA Pro 3 Smart Extra Battery Specifications

Color	Black & Galactic Silver
Weight	33 kg \| 72.7 lbs
Dimensions	694 × 295 × 215mm \| 27.3 x 11.61 x 8.4
Capacity	4096 Wh
Output	40V-58.4V=100A Maximum
Input	40V-58.4V=80A Maximum
Display	LED Array
Discharge Temperature	-10°C ~ 45°C \| 14 ~ 113°F
Charge Temperature	0°C ~ 45°C \| 32 ~ 113°F
Storage Temperature	-10°C ~ 45°C \| 14 ~ 113°F
Wheels Support	No
Tie Rod Support	No
Stack	Horizontal or Vertical
Connection	1 x Extra Battery Port

Is Outbound Power an Authorized Dealer?

Yes! Outbound Power is an Authorized Dealer for every single brand and product on our store.

How long will it take for my order to arrive?

Shipping times vary depending on your location and the product or products ordered.

Order Processing Time
Most products are processed within 1-3 business days. If there is a delay in processing your order, we will alert you with as much information as possible about what to expect.

After order processing is complete, you will receive tracking information to monitor your order while it is in transit.

Order Shipping Time
Following processing, it may take between 3 and 8 days to arrive, depending on your location.

Please refer to the product page for your item and reference the estimated delivery time frame for more details.

Additionally, you can see the estimated delivery time frame during checkout and receive a tracking number once your order ships.

What are your shipping rates? Do you offer free shipping?

Everything on our store ships for free. Really!

What is Outbound Power's return policy?

Most items may be returned within 30 days of delivery. Please refer to our Returns & Exchanges policy to determine what items are eligible. Returns are not accepted beyond 30 days following delivery.

Are Outbound Power products used/old/refurbished?

Everything sold on our website is brand-new.

Do you price match?

No — we price BEAT! Please refer to our Price Beat Promise for full details.

Amazing Products and Customer Service

I'm an Ecoflow adopter with the Delta Pro 3 setup. I recently saw a good deal on the second battery to complete one full setup. Do to the expense, I drug my feet a little to make sure I was making a solid decision.

While waiting (thinking) for a day or so, I received a call from Outbound. Normally, I'm not a fan of sales if I can be honest but, I took the call based on my past satisfaction with the company. After talking with the nice young lady for a few minutes, I decided to move forward. No pressure or odd sales tactics, I assure you. To my surprise, when I checked out, I had an additional discount added to my already amazing discount. In short, it was worth the journey and the delivery was a day ahead of schedule, no drama in integrating the battery and another happy customer.

Thanks Outbound Power (and your no pressure sales staff).
KL

Hi KL,

Thank you so much for taking the time to share this — what an awesome review to read. I’m really glad our team was able to connect with you at just the right moment, and even more glad to hear the call felt helpful rather than sales-y. That’s exactly the experience we strive for.

It’s great to know the extra discount was a pleasant surprise and that your new DELTA Pro 3 battery integrated smoothly into your setup. That complete system is a powerhouse, and I’m thrilled you’re enjoying the journey with it.

If you ever need anything — questions, ideas, or help planning the next step of your setup — I'm always here and happy to assist.

Thanks again for your trust and for being part of the Outbound Power family, KL!

Thanks!

I prefer to work with small companies. For several reasons..
Smaller companies rely on every sale, they are more likely to help you get the correct product at the best price.
The real benefit is after the sale. CS and tech support are more likely to be local and not in a call center in India.
They will have better product knowledge and you are more likely to speak to someone who understands how English is spoken in the US.
Outbound Power fills my requirements very well.
Thanks guys

Hi Ray,

Your note really resonated with us. As a small business, every single order and every customer relationship genuinely matters, and hearing that you value the same things we do—personalized service, real conversations, and knowledgeable support—means a lot.

We work hard to make sure every customer gets the right product at the right price, but more importantly, we want you to feel confident that if you ever need help down the road, we’ll be right here to provide it. Thank you for trusting us with your purchase and for supporting a small, dedicated team that loves what we do.

Great addition!

The smart extra battery is a great addition to the Delta Pro 3. This is piece of mind and some extra time for when you may need it most. It's incredibly simple to hook up and it just works. These were priced well at Outbound Power and they were very responsive and a pleasure to work with!

Thank you so much for the kind words!
We're thrilled to hear you're enjoying the Smart Extra Battery with your Delta Pro 3 — it's always great to have that extra peace of mind when it matters most. Glad to know setup was simple and everything just worked!

We truly appreciate your support and are always here if you need anything in the future. Thanks again for choosing Outbound Power!

Great Battery!

Ecoflow knocks it out of the park as this battery adds 4 KW to the Delta 3 plus as an add on!

Hi Robert,

Thanks so much for the 5-star review! We're glad to hear you're loving the EcoFlow DELTA Pro 3 Smart Extra Battery — it really is a powerful upgrade. EcoFlow definitely hit a home run with this one!

If you ever have any questions or need support down the line, we're just a message away.

Nothing but best price

That’s all I felt

Thank you, Chung-Yuan! We’re glad you found the best price with us. If you ever need anything else, we’re here to help!

Fast

The price was right and the delivery was fast. I can hardly wait till this item is on sale again, need a couple more. Thanks

Thank you, Kenneth, for your positive review! We're glad to hear you found the price right and the delivery fast. We appreciate your support and look forward to serving you again when this item goes on sale. Thanks for choosing Outbound Power!

Works well - plug and play

The expansion battery shipped out quickly, it was a plug-and-play install. Thanks for the positive buying experience.

Thank you, Alan, for your fantastic review! We're glad to hear that the Delta Pro 3 expansion battery arrived quickly and that the plug-and-play install was smooth for you. Your positive buying experience is exactly what we strive for, and we're here if you ever need any further assistance. Enjoy your expanded power setup!

Finished off my System

The addition of the new EcoFlow DeltaPro 3 Extra Battery Pack has really allow my system to shine. Before I was depleting my system and requiring supplemental Grid power to charge my system. Now, It able to keep up with my loads and use solar to keep it charged. OutboundPower had that best price and delivery was very quick. I can't be any happier.

Thank you, Michael, for your fantastic review! We're thrilled to hear that the addition of the Delta Pro 3 Extra Battery Pack has completed your system and helped you move away from supplemental grid power. It's great to know that our pricing and quick delivery contributed to your positive experience. We're always here to support your power needs, and your satisfaction is our priority. Thanks for choosing Outbound Power!

Full transparency and fast shipping

This is my first order from outbound and I must say will certainly not be the last. Constant, relevant communication throughout the order process and fast delivery. Outbound has become my “go to” for all my EcoFlow needs.

Thank you, Josh! We're thrilled to hear that your first experience with Outbound Power was a great one. Providing transparency, fast shipping, and great service is what we aim for. We appreciate your trust and look forward to being your go-to for all things EcoFlow!

92%

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I’m so happy I found this site! Outbound Power has so many great products and I was really excited to see the price. I’ve been waiting for Amazon prime days to buy something, a very expensive item, but I happen to see it on this site and I snatched it right up and saved over $500!!! a delivery was quick and actually a day earlier than what they thought it would be.

Thank you so much for the kind words! We truly appreciate you taking the time to share your experience. If you ever have questions about your system or need help choosing equipment in the future, our team is always here to help. Thanks again for your support and welcome to the Outbound Power community!

Expansion batteries

Received the expansion batteries in excellent condition. Warranty registration with the company was smooth with no issues. I’ll definitely place a larger order again when there’s a big sale! 🔋👍

Thank you for the great review! We’re glad to hear your expansion batteries arrived in perfect condition and that the warranty registration process went smoothly. That’s exactly the experience we want every customer to have.

We truly appreciate your support and look forward to helping you with your next system when you’re ready to expand. Thank you for your support!

Excellent

Perfect addition for our SOLIX C1000 gen 1

Thank you for taking the time to leave a review. We're thrilled to hear that the Battery was the perfect addition for your SOLIX C1000 gen 1. We appreciate your support and hope to continue providing you with excellent products!

EcoFlow 500 Watt Alternator charger

So far, it's been working flawlessly with my EcoFlow Delta 3 Plus
It doesn't seem to work well with my EcoFlow River 2 Pro; for some reason, I had to restart the Charger. Every time I tried to charge my River 2 Pro, eventually it wouldn't charge. There is a good possibility I did something wrong in the settings. I didn't buy it to Charger for the River 2 Pro anyway, so no big deal to me. So far, after two days, the EcoFlow Delta 3 Plus hasn't had any issues.

Thank you for taking the time to leave a review. We are glad to hear that it has been working flawlessly with your EcoFlow Delta 3 Plus. We apologize for the inconvenience you experienced with your EcoFlow River 2 Pro. Our team is here to assist you and make sure you are fully satisfied with our product. Please feel free to reach out to us if you need any help with the settings. We want to ensure that your experience with our charger is nothing but positive. Thank you for choosing Outbound Power.

Jackery Explorer 1000 Plus Portable Power Station | 1264Wh | 2000W | 800W Solar Input

Hi there! Thank you for taking the time to leave a rating for the Jackery Explorer 1000 Plus. We are pleased you're happy with it. Enjoy!

EcoFlow from Outbound Power

Outbound team is fast and responsive. With my purchases so far they have beat everyone else’s prices.

Thank you for your kind words! We’re thrilled you had a great experience with our team and found our prices competitive. We truly appreciate your support and look forward to serving you again soon.

Review of EcoFlow DELTA Pro Ultra X Whole-Home Backup

I purchased the Delta Pro Ultra X with two batteries at the end of 2025 from Outbound Power to get the best price. All three components arrived intact in three separate heavy duty boxes with ample custom molded padding to protect the units from shipping mishaps. I stacked the 3 units on the included caster tray in a new tiny home, and used the unit after a firmware update to my satisfaction. After using the unit for a short while, I charged the unit with a Honda EU3000i gas generator. A week later I installed two solar arrays, totaling 4400 watts with 2 sets of (5) 440 watt panels. I live in Southern California, so this allowed me to be fully charged in an hour or two of full morning sun. The unit has been powering the tiny home which came with a 50A shore power connection. I ran a circuit from the wall nearest the EcoFlow under the tiny home and connected to power panel via the shore power 50A outlet, by removing the outlet and splicing in the new circuit. The unit will run the tiny home no problem and has been on since the end of 2025. I may consider two more batteries after running all my consumer calcs to be 100% off grid, all electric, while satisfying San Diego County's 4 day battery reserve capacity for permitted off grid application such as mine. I'm very happy with this unit. I run Starlink, the refrigerator, an on demand propane water heater (at this time) and a minisplit, plus an inductive cook top, oven, washer/dryer, lights, etc without any issues. The simplicity of installation is peace of mind, and being plugged into the sun feels good every day. Outbound power has reached out and offered to assist if the need should present itself. So far so good!

Hello Jamie,

Thank you for taking the time to leave a review for the EcoFlow DELTA Pro Ultra X Whole-Home Backup. We appreciate your detailed feedback and are happy to hear that you are satisfied with your purchase.

It's great to know that your unit arrived safely and that you were able to easily set it up in your tiny home. We're glad that the firmware update met your expectations and that you were able to quickly charge the unit using a Honda EU3000i gas generator.

We're also pleased to hear that the solar arrays are working well for you and providing enough power for your tiny home. It's wonderful that you are able to be fully charged in just a few hours of sunlight. We understand the importance of being fully off-grid and are happy to hear that this unit is helping you achieve that.

Thank you for choosing Outbound Power as your supplier. We are always here to assist you with any further needs or questions that may arise.

We hope you continue to enjoy the simplicity and reliability of your EcoFlow DELTA Pro Ultra X. Thank you for being a valued customer.

Works Great. Very useful and a must have if you have Ultra X

Thank you for the great review! We’re glad to hear it’s working well for you. If you ever have questions or want help getting even more out of your setup, we’re here for you.

Worth every penny!!

Runs my fridge and freezer while being mobile in my food trailer. Get interface and features. Great product.

Hi there!

Thank you so much for taking the time to leave such a wonderful review of the Anker SOLIX C1000 Gen 2 Portable Power Station! We’re thrilled to hear that it’s meeting your needs and reliably running your fridge and freezer while you’re on the go in your food trailer.

It’s especially great to know that you’re enjoying the interface and features — Anker did a fantastic job designing this unit, and we’re glad it’s delivering the performance you were looking for.

Thank you again for your support, and we wish you continued success and happy trails ahead!

Peaceful Relief

We have a son with severe autism. If he is awake, he is on his computer and tablet. But if the power goes out, big trouble as he gets extremely upset. This power supply will help keep him entertained for a few hours, hopefully long enough for the power to come back.

Thank you so much for taking the time to leave us a review. We’re truly grateful you chose the Jackery Explorer 500, and it means a lot to hear that it’s helping provide stability and comfort for your son during unexpected outages. Having reliable backup power in moments like those can make all the difference. Thank you for choosing Outbound Power!

We sincerely appreciate your thoughtful review and your trust in us. If you ever need anything at all, we’re always here to help.

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