EcoFlow’s Delta 2: Abundant Stored Energy (and Charging Options) for You

As I briefly noted back in mid-November, I ended up replacing my initial failed-experiment lithium battery-based portable power unit, Energizer’s PowerSource Pro Battery Generator:

with two EcoFlow successors, the smaller RIVER 2:

and this writeup’s subject, the DELTA 2, which I bought in claimed factory-refurbished condition (albeit, like the RIVER 2, also seemingly actually brand new) from EcoFlow via eBay in mid-September on sale (20% off list price) for $479 with an included 2-year extended warranty:

Why both? Or said another way, how do they differ? As you can likely already tell from the stock photo of each, the DELTA 2 is the huskier of the two:

That said, EcoFlow puts the DELTA 2’s larger volume to good use with 4x the storage capacity: 1,024 Wh versus 256 Wh with the RIVER 2. The expanded front, rear and sides’ cumulative real estate also affords the DELTA 2 a larger and broader allotment of output power ports:

• Six AC (four two-prong, two three-prong with ground): 120V, 50Hz/60Hz, 1800W (along with 2200W at sub-120V per X-Boost technology, as detailed in my RIVER 2 coverage, and 2700W surge), pure sine wave, not simulated
• Two USB-A DC: 5V, 2.4A, 12W max
• Two USB-A “Fast Charge” DC: 5V @ 2.4A / 9V @ 2A / 12V @ 1.5A, 18W max
• “Cigarette lighter” car DC: 12.6V, 10A, 126W max
• Two DC5521 DC: 12.6V, 3A, 38W max (DC5525 adapter cable also included in kit)
• And two USB-C DC: 5/9/12/15/20V 5A, 100W max (unlike with the RIVER 2, however, these can’t do double-duty as charging input ports)

Unlike the RIVER 2, the DELTA 2’s storage capacity can be further expanded to between 2 kWh and (beyond) 3 kWh by tethering it to a separate DELTA 2, DELTA MAX or DELTA 2 MAX extra battery via its integrated XT150 connector:

That same XT150 connection also enables in-vehicle fast charging at up to 800W using the Alternator Charger, which I also now own ($319.20 on sale) and plan to install in my van soon:

Unfortunately, the very cool (and similar) looking PowerStream residential power unit, which I’m guessing also communicates with the DELTA 2 over XT150, isn’t currently available in the United States due to regulatory restrictions on plug-in grid solutions.

But the XT150-compatible Smart Generator is:

It’s a bit of an enigma, at least to me, given the company’s seeming heavy emphasis on solar and other renewable energy recharging sources. But hey, when the sun’s not shining but your battery’s drained, I suppose this gas-powered generator will do in a pinch instead. And although the product page implies that it only works with higher-capacity DELTA Pro and Max units, this company-published video confirms that it’s mainstream DELTA 2-compatible, too:

Whereas the RIVER 2’s XT60i DC charging input, usable with both solar and “cigarette lighter” car sources via cable adapters, is 110W max (for solar, specifically, 100W for car), the one in the DELTA 2 is beefier, supporting (again, for solar) an 11-60V and up to 15A/500W max input. Last September, I also bought two refurbished 220W second-generation EcoFlow solar panels, on sale at the time for $299 each inclusive of a two-year extended warranty:

which I’ll be cable-extending and in-parallel combining:

Stand by for coverage of them, along with hands-on impressions of the entire setup, to come.

What about AC charging? Although, as previously mentioned, the DELTA 2 has 4x the storage capacity of its RIVER 2 sibling, the charging speeds are surprisingly similar. Whereas the RIVER 2 will charge from 0% to full in 60 minutes, EcoFlow claims that the DELTA 2 will get to 80% in 50 minutes and completely full in 80 minutes. Photos taken during the first-time charging of my unit show that the initial charging rate:

automatically slows down as the full-charge threshold nears (note the input power variance):

and is eventually reached:

Here are those same first two charging segments captured by the wireless-tethered mobile app:

which is capable of simultaneously communicating with both of my EcoFlow devices:

assuming they’re both powered on at the time:

And what of generational enhancements and broader differences? As with the RIVER-to-RIVER 2 sequence I discussed in my recent coverage, EcoFlow also evolved the DELTA 2’s core battery technology from its precursor’s NMC (lithium nickel manganese cobalt), which is only capable of a few hundred recharge cycles before its maximum storage capacity degrades to unusable levels in realistic usage scenarios, to a LiFePO4 (lithium iron phosphate), also known as LFP (lithium ferrophosphate), battery formulation. Whereas the first-generation DELTA was guaranteed for only 500 recharge cycles, with the DELTA 2 it’s 3,000 (in both cases to 80+% of the original battery pack capacity), along with offering a boosted 5-year warranty.

And last September, EcoFlow launched not only the RIVER 3 family but also its first two DELTA 3 devices. The first, the DELTA 3 Plus, is now shipping as I write these words at the end of 2024:

Improvements versus the DELTA 2 predecessor include:

faster switching from wall outlet-sourced to inverter-generated AC (higher power, too) for more robust UPS functional emulation, as with the RIVER 3, along with improved airflow (leading to claimed 30 dB noise levels in normal operation), newer-generation denser 40135 batteries (translating to smaller dimensions and lighter weight, along with a boosted recharge cycle count to 4,000), expansion support up to 5 kWh, and even faster AC charging (sub-1 hour to 100%).

That all said, the DELTA 3 Plus has the same 1-kWh capacity as the non-Plus DELTA 2. What then, of the baseline DELTA 3 also briefly mentioned in last September’s unveiling, and supposedly available in October? Detailed specs are not yet public, at least to the best of my knowledge, as I submit this writeup. Instead (or in addition?), EcoFlow has stealth-launched the DELTA 3 1500:

whose two-color-option styling is reminiscent of the DELTA 2 but with boosted 1.5 kWh capacity and other tweaks. Specs are also scant for this device, but the Reddit crowd was able to dig up a user manual. My guess? EcoFlow is struggling to source enough lithium batteries (brand new DELTA 2 supplemental batteries are also MIA right now, although refurbs occasionally appear on eBay, the company website, etc.) and is dynamically evolving its product line in response.

In closing, after re-reading this piece, I realize that I may have come off as a bit (or more than a bit) of an EcoFlow “fanboy”. To be abundantly clear…I paid for all this gear myself (with no post-publication kickbacks), and the company doesn’t even know I’m doing these writeups. I just think that the products and their underlying technologies are quite cool. Agree or disagree? Let me know your thoughts in the comments!

—Brian Dipert is the Editor-in-Chief of the Edge AI and Vision Alliance, and a Senior Analyst at BDTI and Editor-in-Chief of InsideDSP, the company’s online newsletter.

Related Content

• A holiday shopping guide for engineers: 2024 edition
• Multi-solar panel interconnections: Mind the electrons’ directions
• EcoFlow’s RIVER 2: Svelte portable power with lithium iron phosphate fuel
• The Energizer 200W portable solar panel: A solid offering, save for a connector too fragile

The post EcoFlow’s Delta 2: Abundant Stored Energy (and Charging Options) for You appeared first on EDN.