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EcoFlow DELTA 2 Max Smart Extra Battery

EcoFlow DELTA 2 Max Smart Extra Battery

Save $164.99 Save $164.99
Original price $1,263.99
Original price $1,263.99 - Original price $1,263.99
Original price $1,263.99
Current price $1,099.00
$1,099.00 - $1,099.00
Current price $1,099.00
in stock, ready to be shipped

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5-Year Warranty

Off Grid Stores is an authorized retailer of EcoFlow products. Because of this, we pass on EcoFlow's manufacturer warranty to you.

Product Highlights
  • Expandable capacity- Increase the capacity of DELTA 2, DELTA Max and DELTA 2 Max with an extra 2048Wh.
  • Triple power at up to 30% lower cost-2-6kWhexpandable capacity to fit your energy storage needs. Add up to two DELTA 2 Max Smart Extra Batteries to gain a capacity of 6144Wh. And it's up to 30% more affordable than a power station of the same capacity.
  • 10-year lifespan with an LFP battery- Get 10 years of daily use until it hits 80% of its original capacity. Embrace the 3000+ charging cycles enabled by the LFP battery chemistry.
  • Easy to use- Plug-and-play without setup. And use the EcoFlow app to monitor and control the DELTA 2 Max Smart Extra Battery.
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Simply contact our customer service chat before purchasing to redeem this exclusive offer.

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Orders are typically processed and shipped from our warehouse within 1-3 Business Days (excluding weekends and holidays).

After leaving our warehouse, the expected delivery time is 3-4 Business Days, resulting in an average total shipping and handling time of 4-7 Business Days.

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EcoFlow DELTA 2 Max Smart Extra Battery

EcoFlow DELTA 2 Max Smart Extra Battery

Expandable capacity

Increase the capacity of DELTA 2 Max with an extra 2048Wh.

Triple the power

2-6kWh expandable capacity to fit your energy storage needs. Add up to two DELTA 2 Max Smart Extra Batteries to gain a capacity of 6144Wh, ideal for home backup, RVing, outdoor adventures, and everyday use. Much more affordable, it costs up to 30% less than a power station of the same capacity.

10-Year Long-lasting LFP Battery

Durable, Safe, Lightweight

With its upgraded LFP battery chemistry, the DELTA 2 Max Smart Extra Battery has a lifespan of 3000 complete cycles until it reduces to 80% capacity. You'll get pretty much 10 years of power, even if you use it every day. That's 6× longer than other power stations with a similar capacity and output.

Easy to use

There's no setup. Just plug it into your power station for more energy storage. Using the EcoFlow app, you can charge and monitor the DELTA 2 Max Smart Extra Battery with ease.

Stackable, space-saving design

Featuring an ergonomic, compact design, the DELTA 2 Max Smart Extra Batteries can be securely stacked on top of power stations and each other to save space and minimize clutter.


EcoFlow DELTA 2 Max Smart Extra Battery
General info
Model EFD350-EB
Weight 42lbs
Dimensions 18 in x 9 in x 11 in
Capacity 2,048Wh
Input Ports
Extra Battery Port Input 51.2V= 2000W Max
Output Ports
Extra Battery Port Output 51.2V=3,200W Max
Battery Info
Battery Type LFP
Cycle Life 3,000 cycles to 820% + capacity
Protection Type Over Voltage Protection, Overload Protection,
Over Temperature Protection, Short Circuit Protection,
Low Temperature Temperature, Low Voltage Temperature,
Overcurrent Protection
Operating Temperature
Optimal Operating Temperature 20°C - 30°C
Discharge Temperature -10°C- 45°C
Charging Temperature 0°C- 45°C


EcoFlow DELTA 2 Max Smart Extra Battery

DELTA 2 Max Smart Extra Battery

x 1

Extra Battery Cable

x 1

User Manual

x 1

EcoFlow Warranty Card

x 1

Frequently Asked Questions

Which portable power station is compatible with the DELTA 2 Max Smart Extra Battery?

DELTA 2, DELTA Max, and DELTA 2 Max are compatible with the DELTA 2 Max Smart Extra Battery.

How many extra batteries can I use with a portable power station?

DELTA 2 supports only 1 extra battery while the DELTA Max and DELTA 2 Max support up to 2.

Can I charge the extra battery without connecting to a power station?

Yes. You can use a Smart Generator to charge an extra battery even when it's not plugged into a power station. All other charging methods require it to be connected to a power station.

What makes the Smart Extra Battery "Smart"?

This battery can be monitored and controlled on the EcoFlow app.

User Manuals & Files:

EcoFlow DELTA 2 Max Smart Extra Battery User Manual

Download Now >

Customer Reviews

Based on 6 reviews
Daniel Hoynacki
Dependable on line store

I purchased the Delta Max 2 and then this smart extra battery to go with it from Off Grid Stores. Delivery was right on time and the ordering was convenient at their web site. They had the lowest price that I found and had no problems. I am very satisfied with the EcoFlow products and hoping for many years of usage.

Delta2 max and delta 2 max smart extra battery

I work in a construction with no temporary power and this power bank help me a lot with charging my batteries and power for my microwave

John Marshall
5 Star Outfit

I ordered an EcoFlow Delta 2 max with 2 -400 watt solar panels. The merchandise was shipped as promised and the boxes arrived in great condition. These guys provide excellent products, knowledge and service. And, the price is right.


This is great addition to the ecoflow 2 max👍🏾

Richard Benvenuti
Ecoflow Delta 2 Max extra smart battery

Purchased my Delta 2 Max with 2 extra batteries and (2) 400 watt solar panels. . That just in case we had some type of an EMP or grid failure, that not only I, but also my wife, could handle the weight and easily set up the system. That after consultation with Tom Cormier of Off grid Stores, decided this system would work well for us. All components are in a Faraday cage charged up and ready for action. This was all to compliment my natural gas powered whole house generator and two smaller units. That should there be a long term event, then most likely the grid will be down, thus no natural gas, no gasoline for the other gen sets. That along with our other preps we feel this setup should sustain us for an extended event. Great peace of mind.