EcoFlow Inc. via Amazon has
2048Wh ECOFLOW Delta 3 Max LiFePO4 3400W X-Boost Portable Power Station (EF-DL-H02-3M) on sale for $799 - $39.95 when you apply promo code
CYC4P77D at checkout =
$759.05.
Shipping is free.
Thanks to Community Member
MinhTrinh for sharing this deal.
Note: Promo codes are typically for one-time use and don't always apply seamlessly. If you run into this issue, refresh the page, re-enter the code, or revisit the cart page.
Product Details:
- Ultra-Fast Charging, 0–80% in Just 1.13 Hours – Thanks to EcoFlow's advanced X-Stream technology, DELTA 3 Max can recharge from 0–80% in just over an hour. That means less waiting and more doing, whether you're preparing for a blackout, charging before a road trip, or topping up at the campsite. Reliable power is always ready when you need it most.
- Up to 3400W Continuous X-Boost Mode – Power 99% of Appliances – With an impressive 3400W X-Boost output, this portable power station easily runs high-demand appliances like fridges, microwaves, and even power tools. From emergency backup to RV adventures, enjoy peace of mind knowing your essentials stay powered without overload.
- Ultra-Quiet Performance & Rapid 10ms Transfer Time – Designed for home backup, DELTA 3 Max kicks in with less than 10ms transfer time, keeping sensitive electronics like computers and medical devices safe from outages. Plus, its ultra-quiet operation ensures your nights remain peaceful—no noisy distractions during use.
- Lighter & Durable Design, Built for 10 Years of Daily Use – DELTA 3 Max engineered with a long-lasting LiFePO4 battery. Its lighter, durable build makes it easier to carry from your home to your RV or campsite without sacrificing strength or performance. EcoFlow DELTA2 Max electric generator also comes with an extended 5-year service.
- Smarter App Control – Save on Costs Without Sacrificing Comfort – Connect with the EcoFlow app to monitor energy use in real time, set smart priorities, and cut electricity costs. Easily manage charging and discharging schedules, all while ensuring your comfort and convenience remain top priority.
+ Free Shippingat Amazon
Top Comments
D2M: 2x inputs, 60V max, 15A. 60Vx15A = 900W!
D3M: 1x input, 60V Max, "500W" max. So ~8.333A, let's assume 8A. A 44% reduction in solar input capacity.
60V max input is bad enough. I have two Silfab 410W panels. Max power voltage 38V. Open Circuit Voltage 45.92V. So I can't even use these two panels in series.
LivelyTree6515:
Good on you for asking about MPPT. And good on the others for answering nicely!
When you consider panels for an EcoFlow or similar device, you'll want to design by the OPEN CIRCUIT voltage of the panels, not the Max Power voltage.
When putting panels in series, the voltage is the sum of all panel voltages.
When putting panels in parallel, the amperage is the sum of all panel amperages.
For the sake of simplicity, consider that you have 2x panels. Both the same:
Max power voltage 40V
Max open circuit voltage: 46V
Amps: 12A
Put them in series? 80V max power, 92V max open circuit, 12A.
Put them in parallel? 40V max power, 46V max open circuit, 24A!
Multiply Max power by Amps in both cases: you get 960W.
You always want to design based on the Max Open Circuit Voltage. So that in the "worst case", your voltage remains below the MPPT's max (60V in the case of both the Delta 2 and 3 Max devices).
Exceed the MPPT input voltage, and it should shut itself off. But beyond a certain voltage, you're very likely to FRY it. So best to always stay below that threshold.
Don't take my word for any of this, I'm not an expert. It's critical to do your own research. There's a lot of good stuff to learn about all of this. Not very complicated either. If I've said anything incorrect here, hopefully others will correct me.
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31 Comments
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solar panels connect to the mppt. they come in different sizes but the mid size ecoflows are all 500w and 50v max. so the most solar you can collect with this model is 500wh, where with 2x mppt you could collect 1000wh
You can in theory hook up 12v panels up to 800w and use the battery port and a ecoflow alternator charger + 500 solar each for a total of 1800... I've not seen it done, but might work. Unfortunately car cigarette lighter is only good for about 100-120w max and through the cigarette I think is limited to 8a throughput.
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The price point for this battery is remarkable in this deal, but I would still hesitate to buy it over the Delta 3 Ultra or the Delta 3 Max+ unless you know exactly what you want.
If you are planning on using solar, you'll really appreciate having 2 solar inputs (rather than 1 in this device). If you are planning on expanding with extra batteries, this doesn't let you.
If you want a reliable beast of a backup battery, this is great. It's got most of what I love about the Delta 2 Max but with better efficiency (less fan noise is biggest difference). Plug this thing into the wall and then plug your devices right into it- you've got pass-through power and 2kw of outage protection.
If you'd rather have an off-grid solution, this works OK, but I'd steer toward D2M if you plan solar input for the same price.
The price point for this battery is remarkable in this deal, but I would still hesitate to buy it over the Delta 3 Ultra or the Delta 3 Max+ unless you know exactly what you want.
If you are planning on using solar, you'll really appreciate having 2 solar inputs (rather than 1 in this device). If you are planning on expanding with extra batteries, this doesn't let you.
If you want a reliable beast of a backup battery, this is great. It's got most of what I love about the Delta 2 Max but with better efficiency (less fan noise is biggest difference). Plug this thing into the wall and then plug your devices right into it- you've got pass-through power and 2kw of outage protection.
If you'd rather have an off-grid solution, this works OK, but I'd steer toward D2M if you plan solar input for the same price.
Hard to imagine the 50% is real, anyone know what these normally go for?
i paid 679 for my delta 2 max refurb on ebay month of two ago
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Precisely. Delta 3 Max is a downgrade relative to the Delta 2 Max, from the point of view of solar charging.
D2M: 2x inputs, 60V max, 15A. 60Vx15A = 900W!
D3M: 1x input, 60V Max, "500W" max. So ~8.333A, let's assume 8A. A 44% reduction in solar input capacity.
60V max input is bad enough. I have two Silfab 410W panels. Max power voltage 38V. Open Circuit Voltage 45.92V. So I can't even use these two panels in series.
LivelyTree6515:
Good on you for asking about MPPT. And good on the others for answering nicely!
When you consider panels for an EcoFlow or similar device, you'll want to design by the OPEN CIRCUIT voltage of the panels, not the Max Power voltage.
When putting panels in series, the voltage is the sum of all panel voltages.
When putting panels in parallel, the amperage is the sum of all panel amperages.
For the sake of simplicity, consider that you have 2x panels. Both the same:
Max power voltage 40V
Max open circuit voltage: 46V
Amps: 12A
Put them in series? 80V max power, 92V max open circuit, 12A.
Put them in parallel? 40V max power, 46V max open circuit, 24A!
Multiply Max power by Amps in both cases: you get 960W.
You always want to design based on the Max Open Circuit Voltage. So that in the "worst case", your voltage remains below the MPPT's max (60V in the case of both the Delta 2 and 3 Max devices).
Exceed the MPPT input voltage, and it should shut itself off. But beyond a certain voltage, you're very likely to FRY it. So best to always stay below that threshold.
Don't take my word for any of this, I'm not an expert. It's critical to do your own research. There's a lot of good stuff to learn about all of this. Not very complicated either. If I've said anything incorrect here, hopefully others will correct me.
Sign up for a Slickdeals account to remove this ad.
The price point for this battery is remarkable in this deal, but I would still hesitate to buy it over the Delta 3 Ultra or the Delta 3 Max+ unless you know exactly what you want.
If you are planning on using solar, you'll really appreciate having 2 solar inputs (rather than 1 in this device). If you are planning on expanding with extra batteries, this doesn't let you.
If you want a reliable beast of a backup battery, this is great. It's got most of what I love about the Delta 2 Max but with better efficiency (less fan noise is biggest difference). Plug this thing into the wall and then plug your devices right into it- you've got pass-through power and 2kw of outage protection.
If you'd rather have an off-grid solution, this works OK, but I'd steer toward D2M if you plan solar input for the same price.
Good advice.
I'll add that the Delta 2 Max, Delta 3 Max, and even the Delta 3 "Ultra" all have a maximum solar input voltage of 60V. Maybe understandable for the Max devices, but for an "Ultra" it's a f*cking joke. Good luck finding a panel with decent output with a max open circuit voltage of 30V or less.
On the Ultra, it would be MUCH more consumer friendly to have 120V max input. That way more than one panel could be put in series, cranking the voltage and minimizing losses over distance. If I have two 45V panels 100 feet from my EcoFlow, I have to wire each one separately on the Ultra. And in order to keep losses below 3VDC, I need 6AWG wire, and I need two separate circuits. One for each solar input. If I could put them in series, I could use 10AWG wire, and I'd only need ONE circuit.
6AWG THHN, $1.68/foot at bLowe's. 100 feet = $168. Two circuits, $336.
10AWG THHN, $0.68/foot. 100 feet = $68. ONE circuit, $68.
$268 more. Thanks, EcoFlow!
They don't even list the max solar input voltage on the specs for the Delta 3 Max or even the Ultra
What a f*cking joke. Even the Delta Pro has a 150VDC solar input capacity!
Quote from sagefool
Hard to imagine the 50% is real, anyone know what these normally go for?
i paid 679 for my delta 2 max refurb on ebay month of two ago
Bro talking about a different product thats refurbished. Smh
The price point for this battery is remarkable in this deal, but I would still hesitate to buy it over the Delta 3 Ultra or the Delta 3 Max+ unless you know exactly what you want.
If you are planning on using solar, you'll really appreciate having 2 solar inputs (rather than 1 in this device). If you are planning on expanding with extra batteries, this doesn't let you.
If you want a reliable beast of a backup battery, this is great. It's got most of what I love about the Delta 2 Max but with better efficiency (less fan noise is biggest difference). Plug this thing into the wall and then plug your devices right into it- you've got pass-through power and 2kw of outage protection.
If you'd rather have an off-grid solution, this works OK, but I'd steer toward D2M if you plan solar input for the same price.
Afraid I don't have a decibel meter, but the official reading for D3M+ is under 25 decibels.
The noise is considerably less than the D2M, but more importantly- it doesn't come on nearly as often, either. I really only hear it when I am max-charging the AC or depleting the unit at over 1500w.
Keep in mind, that's the D3M+ and not the D3M which is what this deal is about. Both are going to be much more efficient and quiet than the D2M.
I recently bought the Anker Amazon renewed deal and actually wish I had waited for the ecoflow. I like how my eco flow batteries connect to wifi. Being restricted to Bluetooth like with my Anker solix means you have to be very close to the device to control it.
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One good thing also about Ecoflow is the bluetooth doesn't shut off unlike the stupid Anker that shuts off after 5 hours or something and you have to manually hold down the bluetooth button for a few seconds to turn it back on.
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