Head-to-head test
EcoFlow DELTA 3 Max vs EcoFlow DELTA 3800 Gen4One Add-On Battery Matches a Whole DELTA 3 Max. Need It?
EcoFlow DELTA 3 Max vs EcoFlow DELTA 3800 Gen4: the DELTA 4 (3800) holds 3,763 Wh against 2,048 Wh, takes 2,000 W of solar and adds extra batteries, but it costs more per watt-hour and weighs 22.7 lb more. Buy the DELTA 3 Max for a box you carry; pick the DELTA 4 (3800) only if you'll grow it into home backup.
Black Friday · 23 days out
Price to beat:DELTA 3 Max $799
The lowest we have recorded. A Black Friday price above it is a sale this unit has already had.
Full profiles: EcoFlow DELTA 3 Max → · EcoFlow DELTA 3800 Gen4 →
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
Spec deltas
Gunner’s take
Whole-Home Backup Tester
These two aren't the same kind of purchase.
The DELTA 3 Max is a finished 2,048 Wh box with no battery port. The DELTA 4 (3800) starts at 3,763 Wh and takes up to two of EcoFlow's extra batteries, for 4 to 12 kWh by EcoFlow's figureB6.
The growth is what the extra money buys.
The DELTA 3 Max sells for $899 and EcoFlow lists the DELTA 4 (3800) at $2,199B10, which makes it about a third more per watt-hour. It's also 67.5 lb against 44.8 lb, and it ships in late NovemberB10.
So the question is whether you're buying a box or starting a system.
For a box you carry, use and put away, the DELTA 3 Max does the everyday jobs for $1,300 less. For a house you mean to back up properly, the DELTA 4 (3800) is the first piece, and only the first.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
The DELTA 3 Max is complete at that size. The DELTA 4 (3800) is a hub, and its premium pays off when you plug the next piece in. Left alone, it's a bigger battery with a port you paid for and never used.
DELTA 3 Max: 2,048 Wh, no expansion portDELTA 4 (3800): up to two extra batteries, the DELTA Pro 3 battery or the 2,048 Wh DELTA 3 Max Plus batteryB6EcoFlow quotes 4–12 kWh of expandable capacityB6
Why it mattersIf you can name the extra battery you'll add in the next year or two, buy the DELTA 4 (3800); if you can't, the port is money spent on a maybe.
weight
That's the DELTA 3 Max's real weakness, and I'd rather say it now. A one-night outage it handles. A storm that takes the power for days means a full recharge before each evening, and the 3800's reserve is what its extra 22.7 lb is carrying.
8-Hour Blackout: 1,645 Wh; the DELTA 3 Max ends with 96 Wh, the DELTA 4 (3800) with 1,554 WhWeights: 44.8 lb against 67.5 lb
Why it mattersIf your outages are measured in days, the DELTA 4 (3800) earns its weight; if they're measured in hours, the DELTA 3 Max is plenty.
That's a battery that can live off a roof. With a real array it refills over one good midday, and with an extra battery on the port it can bank a sunny afternoon for the night instead of turning the surplus away. With one folding panel, the panel is the limit and most of that input sits idle.
DELTA 4 (3800): two solar inputs at 1,000 W each, 2,000 W in all, at 11 to 60 VB5Capacity 3,763 WhVan Life Daily needs 4,685 Wh; the DELTA 4 (3800) alone comes up 1,486 Wh short
Why it mattersIf you plan an array on a roof or shed, the DELTA 4 (3800)'s inputs earn their place; for one folding panel, they don't.
The specific dimensions that decide these two units — everything else is a tie.
Growth Path
Selected because: Only the DELTA 4 (3800) takes extra batteries; the DELTA 3 Max stops at 2,048 Wh.
solar input
The DELTA 4 (3800) is a foundation, and the DELTA 3 Max is a finished room. EcoFlow lists two extra batteries for the 3800, the DELTA Pro 3 battery and the 2,048 Wh DELTA 3 Max Plus battery, and up to two of them connect through its expansion adapterB6. The DELTA 3 Max has no port to plug either into.
EcoFlow's 4 to 12 kWh is the scale of a house, not a campsiteB6. That's the only job that justifies paying a third more per watt-hour for the base unit. If the plan is a fridge, a router and some lights for one night, the port is a feature you'd never touch.
Your Life, Your Pick
Selected because: The DELTA 3 Max wins no scenario outright, but it finishes four of the six.
The DELTA 3 Max wins no row outright, and it doesn't need to. It finishes a CPAP night, a remote workday and a tailgate with at least 831 Wh to spare each time. Those are the jobs most people buy a box this size for.
Where it loses, it loses on the long days. Weekend Camping's 2,100 Wh leaves it 359 Wh short. Van Life Daily needs 4,685 Wh and even the DELTA 4 (3800) comes up 1,486 Wh short alone, but it has a fix the DELTA 3 Max doesn't, an extra battery on the portB6.
Portability & Form Factor
Selected because: 67.5 lb against 44.8 lb, a 22.7 lb difference for the bigger battery.
weight
At 44.8 lb the DELTA 3 Max goes where you go. Trunk to tailgate, garage to porch, no plan required. The DELTA 4 (3800) at 67.5 lb wants a handle in each hand, and EcoFlow sells a folding cart for it separatelyB7. On basement stairs I'd want a second person.
If it parks for good, the weight stops mattering. A box that feeds a few house circuits gets carried once. That's where the 3800 is headed anyway, and the DELTA 3 Max is the one you'd take camping.
What the Specs Don't Tell You
Selected because: The weight card and the fixed-ceiling card both fire here, and they point at the same choice.
rated cycles
Both cards are fair, and they point the same way. 67.5 lb is a real lift, and the DELTA 3 Max's 2,048 Wh is the most it will ever hold. Carry a small finished box, or park a big one that grows.
The bigger box's wall charger wants a circuit to itself. EcoFlow rates it at up to 1,800 W from the wallB4. At 120 V that's 15 A, the full rating of an ordinary 15 A circuit, so in a garage shared with a freezer I'd turn the rate down in the appB4.
In the makers’ pictures
What you’d actually be living with
Every port, labelled
What plugs in where, and how much it takes
EcoFlow DELTA 3 Max
Front panel
- 1USB-C · 100 WOutUp to 100 W (20 V at 5 A), printed on the panel and in EcoFlow’s specs.
- 22× USB-C · 30 WOutTwo USB-C ports printed 30W. EcoFlow’s specs say 30 W per port and 30 W in total, so the pair share 30 W.
- 3USB-A · 18 WOutUp to 18 W (5 V at 3 A, 9 V at 2 A or 12 V at 1.5 A), printed on the panel and in EcoFlow’s specs.
- 44× 20 A outletsOutFour T-slot 120 V outlets, 20 A max each, sharing 2,400 W in all. X-Boost runs heaters up to 3,400 W, by EcoFlow’s specs.
Photo: EcoFlow · Product image, EcoFlow US store · numbers and labels are ours. Port ratings printed on EcoFlow’s panel and in the specs on EcoFlow’s US store page for the DELTA 3 Max.
Rear panel
- 1AC inInThe AC charging inlet: 100–120 V at 15 A, by EcoFlow’s specs.
- 2Charge-speed switchInSwitches AC charging between FAST and ADJUST, as printed beside it.
- 3Solar in · 500 WInOne XT60 input printed 11–60 V, 13 A max. EcoFlow puts the most solar the unit takes at 500 W.
- 412 V car socket · 10 AOutA 12 V car socket rated 12.6 V, 10 A, 126 W by EcoFlow’s specs, with a 12V ON/OFF button beside it.
No battery port: the base DELTA 3 Max has a single XT60 input and takes no extra battery. The Max Plus adds one.
Photo: EcoFlow · Product image, EcoFlow US store · numbers and labels are ours. Port names and the solar rating printed on EcoFlow’s panel; the rest from the specs on EcoFlow’s US store page for the DELTA 3 Max.
EcoFlow DELTA 3800 Gen4
Front panel
- 1USB-C · 140 WOutUp to 140 W (USB-PD up to 28 V at 5 A). The port for a laptop.
- 22× USB-C · 65 WOutUp to 65 W each. EcoFlow says these two and the USB-A share 16 W when two or more are in use at once.
- 3USB-A · 36 WOutUp to 36 W (5, 9 or 12 V at 3 A).
- 430 A twist-lockOutA three-slot twist-lock marked 30A MAX, rated 30 A at 120 V on the US unit.
- 54× 20 A outletsOutFour T-slot 120 V outlets rated 20 A each, sharing 3,600 W continuous and a 7,200 W surge.
Photo: EcoFlow · Product image, EcoFlow Japan store · numbers and labels are ours. Ratings from EcoFlow’s US spec table; outlet shapes read by us from EcoFlow’s picture, taken of the Japanese unit, which shares the US panel.
Input side
- 12× Solar/DC in · 1,000 WInTwo inputs, each 11 to 60 V, up to 20 A, 1,000 W: 2,000 W of panels in all.
- 2AC in · 1,800 WIn100–120 V at 15 A. Charges at up to 1,800 W, which at 120 V is the whole of an ordinary 15 A circuit.
- 3Battery portIn · OutTakes up to two of EcoFlow’s DELTA 3 Max Plus or DELTA Pro 3 extra batteries; EcoFlow quotes 4–12 kWh.
Photo: EcoFlow · Product image, EcoFlow Japan store · numbers and labels are ours. Ratings from EcoFlow’s US spec table and the panel’s own printing.
Strengths & trade-offs
EcoFlow DELTA 3 Max
Strengths
- +Costs $1,300 less
- +Lighter by 22.7 lb
Trade-offs
- –Weaker inverter (-1,200W) limits appliance compatibility.
- –Sealed capacity — the DELTA 3800 Gen4 can add batteries to grow past 2,048Wh; this one can't.
- –Shorter-lived battery — rated for 4,000 charge cycles vs the DELTA 3800 Gen4's 6,000, so it wears out sooner.
EcoFlow DELTA 3800 Gen4
Strengths
- +Larger battery capacity
- +Higher AC output
- +Faster solar charging
- +Rated for 6,000 charge cycles — much longer battery lifespan
Trade-offs
- –Substantially more expensive (+$1,300) than the DELTA 3 Max.
- –Significantly heavier (+22.7 lbs), making it harder to move.
Will It Power Your Gear?
Scenario math and per-appliance runtimes, modeled from the spec record.
Scenario verdicts
We ran the math on six real-world scenarios. Here's which unit survives your actual life.
SCN-01 · 2 nights · needs 2,100Wh
Weekend Camping
Two nights off-grid with essential comfort
DELTA 3800 Gen4
The DELTA 3 Max doesn't finish — 1,741Wh usable against the 2,100Wh this needs leaves it 359Wh short, about 83% of the scenario covered. The DELTA 3800 Gen4 covers it with 1,099Wh to spare.
Battery budget usedlower = more headroom
LOAD Phone Charger 15W×6h · LED Lights 40W×8h · Box Fan 75W×14h · CPAP Machine 40W×16h
SCN-02 · 8 hours · needs 1,645Wh
8-Hour Blackout
Keep the essentials running through a night without power
DELTA 3800 Gen4
Both get through it. The DELTA 4 (3800) ends with 1,554 Wh, nearly a second night. The DELTA 3 Max ends with 96 Wh.
Battery budget usedlower = more headroom
LOAD Fridge 150W×8h · Router + Modem 20W×8h · LED Lights (4 bulbs) 40W×6h · Phone Charger 15W×3h
SCN-03 · 8 hours · needs 320Wh
CPAP Overnight
Sleep therapy without interruption — the #1 medical use case
Either unit
Both run a CPAP for many nights before either one runs dry, so capacity settles nothing here. Neither does noise: EcoFlow's DELTA 4 figure is a ceiling under heavy load, and neither published figure describes a CPAP's small draw. At the bedside I'd take the lighter, cheaper DELTA 3 Max.
Battery budget usedlower = more headroom
LOAD CPAP Machine 40W×8h
SCN-04 · 8 hours · needs 910Wh
Remote Workday
Full work day off-grid without power anxiety
DELTA 3800 Gen4
The DELTA 3800 Gen4 clears the workday at 28% used, banking 2,289Wh — late work, extra calls, or a second laptop charge without arithmetic. The DELTA 3 Max at 52% also finishes, with 831Wh of slack for the unplanned.
Battery budget usedlower = more headroom
LOAD Laptop 60W×8h · External Monitor 30W×8h · Router + Modem 20W×8h · Phone Charger 15W×2h
SCN-05 · 4 hours · needs 670Wh
Tailgate Party
Game day power for the crew
DELTA 3800 Gen4
Both cover the 670 Wh with plenty left, and the DELTA 4 (3800) keeps more back. You carry 67.5 lb for that reserve, against 44.8 lb.
Battery budget usedlower = more headroom
LOAD Blender 400W×0.5h · LED TV (55") 80W×4h · Bluetooth Speaker 15W×4h · Phone Charger (×3) 45W×2h
SCN-06 · 24 hours · needs 4,685Wh
Van Life Daily
A full day of mobile living — the ultimate endurance test
Neither unit
Neither covers 4,685 Wh alone. The DELTA 4 (3800) comes up 1,486 Wh short and can add an extra battery to close it. The DELTA 3 Max has no port to add one to.
Battery budget usedlower = more headroom
LOAD Mini-Fridge 150W×24h · Laptop 60W×4h · Phone Charger 15W×3h · LED Lights 40W×5h · Fan 75W×8h
The Load Test
RUNTIME = (Wh × 0.85) ÷ LOAD
None of the scenarios above exactly yours? Build it. Toggle what you'd plug in; both units are tested against the combined draw.
Essentials
Comfort & Convenience
High-Draw Appliances
Test duration
8h
Continuous draw
205W
Projected runtime
For this load: DELTA 3800 Gen4 runs 15.6h vs 8.5h.
$2,199 list · direct from EcoFlow
Planning for more than this? Describe your whole setup and get it sized →
Modeled from the spec record — same math as the tables below. Methodology
Runtime by appliance
Real-world runtime estimates for common appliances, modeled at 85% inverter efficiency.¹
Essentials
The basics you need runningscale 0–213.2hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–42.6hHigh-Draw Appliances
These reveal the real limitsscale 0–3.2h¹ Runtime = (capacity × 0.85) ÷ appliance watts. Within each group, all bars share one time scale (the group's longest runtime), so lengths are comparable across appliances; identical runtimes collapse into a single blue/orange bar. Actual runtime varies with battery age, temperature, and simultaneous loads — see methodology.
Conclusion
November 4, 2026
Verdict: the EcoFlow DELTA 3 Max
I'd buy the DELTA 3 Max, unless you're building toward backing up a house. The DELTA 4 (3800) holds 3,763 Wh against 2,048 Wh, takes 2,000 W of solar and has a battery portB6. It also costs $1,300 more, about a third more per watt-hour, weighs 22.7 lb more and ships in late NovemberB10. The DELTA 3 Max finishes a CPAP night, a workday, a tailgate and the 8-Hour Blackout, though it ends that last one with 96 Wh left. If you'll add an extra battery within a year or two, the port is what you're paying for and the call flips.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of November 4, 2026. The links below open EcoFlow's current price.
$879.00 · direct from EcoFlow
Last checked 31 days ago. Prices move — check before you buy.
or check the DELTA 3800 Gen4 price$2,199.00 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated November 4, 2026
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
Not rated for both units (minimum threshold unmet): CPAP, Camping.
Full specifications
ᵈ Derived: price ÷ rated capacity. See the data behind our comparisons →
Comparison ToolAdd more power stations, side by sideOpen Tool →How these numbers are produced
Numeric verification
Every figure on this page traces to our spec database or arithmetic on it — no estimated numbers.
Owner claims
Statements about owner experience are cited to published reviews — see Sources & Research Notes below.
Runtime model
Runtime = (rated capacity × 0.85 inverter efficiency) ÷ device wattage. Solar recharge estimates assume panels deliver 70% of rated output. Cold weather, battery age, and stacked loads reduce real-world results.
Power Score
Computed from 14 published spec dimensions, weighted per use-case bench. Higher is better; a unit must meet a bench's minimum threshold to be rated.
See the full weight table and data sourcing on our methodology page →Class ranking (the star rating)
Each unit's star score is a category ranking, not customer reviews — no buyer opinions feed it. We score every station on size-independent quality (value, output, portability, endurance, ports, warranty, and more), then percentile-rank it against the other units in its capacity class, so a class-leading compact unit and a class-leading whole-home unit can both earn 5★. Here, DELTA 3 Max rates 4.0/5 (43rd percentile of 29 Large-class units), and DELTA 3800 Gen4 rates 4.1/5 (48th percentile of 22 Home Backup-class units).
How the class ranking is computed →Test Notes & Caveats
Hidden gotchas and advantages we spotted that you won't find on the product page.
67.5 lb Wants Two Hands
The DELTA 4 (3800) weighs 67.5 lb, 22.7 lb more than the DELTA 3 Max. It's a two-handed lift and a stair job I'd want help with. If it will live by the panel, you carry it once.
DELTA 3 Max: What You Buy Is the Ceiling
The DELTA 3 Max stops at 2,048 Wh, with no expansion port. The DELTA 4 (3800) starts at 3,763 Wh and takes EcoFlow's extra batteries. That only counts if you buy one, which is the whole question on this page.
Warranty: No Difference
Both units carry the same 5-year warranty, so coverage isn't a tiebreaker here. Both figures are maximums rather than guarantees — they depend on registering the unit in the EcoFlow app, which adds two years to a three-year standard term. Worth saying because the per-dollar framing can suggest otherwise: the DELTA 3 Max works out at 5.6 years of cover per $1,000 spent against the DELTA 3800 Gen4's 2.3, but that spread is the price gap, not the terms.
Battery Lifespan in Real Years
The DELTA 3800 Gen4 is rated for 6,000 cycles vs 4,000. In real life: at daily use, that's 16.4 vs 11 years. At weekend use (twice a week), it's 58 vs 38 years. One caution reading years across different sizes: a cycle is 3,763Wh on the DELTA 3800 Gen4 and 2,048Wh on the DELTA 3 Max, so count lifetime energy — roughly 22,578 kWh against 8,192 kWh over the rated life. After hitting the cycle limit, the battery doesn't die — it drops to ~80% of original capacity, which is still very usable.
Full record above — the Test Desk pick is the DELTA 3 Max.
Check DELTA 3 Max price →or check the DELTA 3800 Gen4 priceOwnership Analysis
What happens after you buy — true cost of ownership, brand trust, and growth potential.
Lifetime value
Service lifeyears at one full cycle per day
Lifetime energy delivered
Cost per delivered kWh
│ warranty ends · Reaching the cycle rating means ~80% capacity remains — degraded, not dead.
Analyst note
The DELTA 3 Max is cheaper to buy, but the DELTA 3800 Gen4 is cheaper to own. At $0.10/kWh over its lifetime vs $0.11/kWh, the DELTA 3800 Gen4's higher cycle life and capacity make each dollar go further over the years.
Growth path
DELTA 3 Max
FIXED CAPACITYFixed at 2,048Wh — a sealed, complete system rather than a starting point. There's no expansion port, so that figure is the ceiling: check it against your longest unplugged stretch before you buy.
Accepts up to 500W of solar. Suitable for a 1-2 panel setup.
Adequate ports for most setups, but heavy users may want a power strip.
DELTA 3800 Gen4
EXPANDABLESupports EcoFlow expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 3,763Wh.
Accepts up to 2,000W of solar. Enough for a serious multi-panel array.
Adequate ports for most setups, but heavy users may want a power strip.
Expansion batteries are EcoFlow-specific. You're investing in the EcoFlow ecosystem.
Realistic full solar rechargeat 70% of rated panel output — see methodology
Analyst note
The DELTA 3 Max is sealed at 2,048Wh, which is fine if that covers you. The DELTA 3800 Gen4 starts at 3,763Wh and can grow beyond it with EcoFlow expansion batteries — real headroom the DELTA 3 Max doesn't have if your needs climb toward partial-home backup.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
EcoFlow DELTA 3 Max
The reviews that exist are hands-on, and they're kind. Reviewers consistently describe it as near silent at moderate load, with an app quiet mode and a charge-speed limit for when it isn'tA1A2. One rated it 8.5 out of 10 and counted its fast recharge and LFP longevity among the best value in the 2 kWh classA4.
Big owner threads haven't turned up yet. Our research found mostly review sites, and some of them mix up the DELTA 3 Max and the DELTA 3 Max PlusA0.
“Whisper-quiet under moderate load — essentially silent at conversational distance; the app adds a low-power quiet mode and a custom charge-speed limit if fan noise bothers you. Fans rise under heavy load but stay quieter than most competitors in the 2kWh class.”
Sources
backuppowerhub.com · thesolarlab.com · androidguys.com
EcoFlow DELTA 3800 Gen4
Nobody has a DELTA 4 (3800) in their garage yet. It went on sale on November 4 and ships in late NovemberB10, so everything here is EcoFlow's US spec table plus our arithmeticB0B5.
If I had one, I'd put a real array on each of its two inputs at a June noon and watch the input figure. EcoFlow rates each input at 1,000 W within 11 to 60 VB5. I'd want to know what it actually pulls with both working, because that decides whether the 3800 can live off a roof.
“Capacity 3,763 Wh, LFP (LiFePO4) cells. EcoFlow sells it as the DELTA 3800 Gen4; buyers and the press call the pair the DELTA 4.”
Sources
us.ecoflow.co · jp.ecoflow.co
Sources & Research Notes
Every owner claim in this report is traceable to a published source. The bracketed references above resolve here.
Recurring owner themes
- Reviewers consistently praise practical quietness (with app-based quiet/charge-limit modes) and the EcoFlow app/ecosystem as differentiators. [DELTA 3 Max · 2 entries]
- Launch-day ledger: every entry is EcoFlow's own US store and documentation, or our labelled arithmetic. No owner or reviewer evidence exists yet. [DELTA 3800 Gen4 · 12 entries]
- A1
“Whisper-quiet under moderate load — essentially silent at conversational distance; the app adds a low-power quiet mode and a custom charge-speed limit if fan noise bothers you. Fans rise under heavy load but stay quieter than most competitors in the 2kWh class.”
backuppowerhub.com — EcoFlow DELTA 3 Max Review; thesolarlab.com — DELTA 3 Max Review · 2026 · [positive]
- A2
“The EcoFlow app is one of the main reasons people migrate to the ecosystem: deep control including a custom charge-speed limit and quiet mode, well beyond the on-device interface.”
androidguys.com / thesolarlab.com — EcoFlow DELTA 3 Max line · 2026 · [positive]
- A4
“Rated 8.5/10 overall — strong across nearly every metric in the 2kWh class, with fast recharge and LFP longevity called one of the best value propositions in the segment.”
backuppowerhub.com — EcoFlow DELTA 3 Max Review · 2026 · [positive]
- B3
“AC outlets: 5 total, four rated 20 A max and one rated 30 A max (on EcoFlow's product images, four T-slot outlets and a three-slot twist-lock). USB-A: one port, 36 W max. USB-C: one at 140 W max and two at 65 W max; the two 65 W ports share circuitry with the USB-A, limited to 16 W total when used together. No 12 V car socket.”
EcoFlow US store, us.ecoflow.com/products/delta-3800-gen4 (spec table, features and FAQ, read 2026-11-04) · 2026-11-04 · [mixed]
- B4
“AC input 100–120 V, 15 A, 50/60 Hz; X-Stream charging up to 1,800 W from a US wall outlet. Our arithmetic: 1,800 W at 120 V is 15 A, the full rating of an ordinary 15 A circuit, so on a shared circuit you would set the charge rate lower in the EcoFlow app.”
EcoFlow US store, us.ecoflow.com/products/delta-3800-gen4 (spec table, features and FAQ, read 2026-11-04) · 2026-11-04 · [mixed]
- B5
“Solar: two inputs, 11–60 V DC at up to 20 A and 1,000 W each, 2,000 W total (XT60i; two XT60i-to-LP60 cables are in the box). EcoFlow lists six charging methods; its 800 W Alternator Charger is limited to 500 W through the Solar/DC port.”
EcoFlow US store, us.ecoflow.com/products/delta-3800-gen4 (spec table, features and FAQ, read 2026-11-04) · 2026-11-04 · [mixed]
- B6
“Extra Battery Port: up to two extra batteries through EcoFlow's Smart Extra Battery Expansion Adapter. Compatible: the DELTA Pro 3 Smart Extra Battery and the DELTA 3 Max Plus (2,048 Wh) Smart Extra Battery. EcoFlow quotes 4–12 kWh of expandable capacity.”
EcoFlow US store, us.ecoflow.com/products/delta-3800-gen4 (spec table, features and FAQ, read 2026-11-04) · 2026-11-04 · [mixed]
- B7
“Weight 67.5 lb (30.6 kg); 16.77 × 11.36 × 12.09 in without handles, 18.76 in long with them. A handle at each end; EcoFlow sells a folding transport cart separately ($109 at launch, listed at $199). EcoFlow calls it the smallest and lightest portable power station in its class (3–4 kWh and 3,600 W).”
EcoFlow US store, us.ecoflow.com/products/delta-3800-gen4 (spec table, features and FAQ, read 2026-11-04) · 2026-11-04 · [mixed]
- B10
“On sale at us.ecoflow.com from November 4, 2026 at $2,199; EcoFlow says it ships in late November. Kits: with two 160 W solar panels $2,899; with a DELTA 3 Max Plus extra battery (6 kWh in all) $2,999. EcoFlow also sells it in Japan, where it went on sale October 30 at ¥240,900.”
EcoFlow US store, us.ecoflow.com/products/delta-3800-gen4 (spec table, features and FAQ, read 2026-11-04) · 2026-11-04 · [mixed]
Research compiled November 4, 2026.
Who Should Buy Which
Buy the DELTA 3 Max if you…
- →It travels. 44.8 lb, which is 22.7 lb less than the DELTA 4 (3800).
- →It rides in the car. It has a 12 V socket, and the DELTA 4 (3800) has noneB3.
- →Your outages last hours, not days. It gets through the 8-Hour Blackout, just.
- →2,048 Wh is all you'll ever need. A CPAP night uses 18% of it.
Buy the DELTA 3800 Gen4 if you…
If neither fits
If you want something you carry one-handed to a picnic table, skip both. Even the DELTA 3 Max is 44.8 lb. A smaller unit such as the DELTA 3 Plus is the better tool.
The Bottom Line
For a box you'll carry and use, buy the DELTA 3 Max. It's lighter, it's the cheaper watt-hour, and it does the everyday jobs. Its one real gap is a thin morning after a long outage.
If you're laying the first piece of a home battery, the DELTA 4 (3800) is the right first piece. The battery port and the 2,000 W of solar are what you'd be paying for, so be sure you'll use them.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
How much does the EcoFlow DELTA 4 (3800) cost in the US?
EcoFlow lists it at $2,199 on its US store, where it went on sale on November 4, 2026, and says it ships in late November. The DELTA 3 Max sells for $899.
Can the DELTA 3 Max add batteries like the DELTA 4 (3800)?
No. The DELTA 3 Max has no expansion port, so it stays at 2,048 Wh. The DELTA 4 (3800) starts at 3,763 Wh and takes up to two EcoFlow extra batteries.
Which extra batteries work with the DELTA 4 (3800)?
EcoFlow lists the DELTA Pro 3 Smart Extra Battery and the DELTA 3 Max Plus Smart Extra Battery, which holds 2,048 Wh. They connect through EcoFlow's expansion adapter, and EcoFlow quotes 4 to 12 kWh of capacity in all.
Is the DELTA 4 (3800) too heavy to carry?
It weighs 67.5 lb, against 44.8 lb for the DELTA 3 Max. It has a handle at each end, and EcoFlow sells a folding cart for it separately. Expect a two-handed lift, and help on stairs.
Can the DELTA 3 Max get through a power outage?
Through one night, yes. Our 8-hour blackout uses 1,645 Wh, and the DELTA 3 Max finishes with 96 Wh left. The DELTA 4 (3800) finishes the same night with 1,554 Wh, most of a second night.
Where to buy
EcoFlow DELTA 3 MaxPick
$879.00
$879.00 · direct from EcoFlow
Last checked 31 days ago. Prices move — check before you buy.
EcoFlow DELTA 3800 Gen4
$2,199.00
$2,199.00 · direct from EcoFlow
Prices may vary by retailer and are subject to change.