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The EcoFlow DELTA 2 Smart Extra Battery is a battery module with no outlets of its own: it connects to an already-installed DELTA 2 with a dedicated cable and doubles its reserve. The capacity of the two bodies is identical, so together they reach a little over two thousand watt-hours without changing the main unit.
Each DELTA 2 accepts only one module of this type, so the starting capacity reaches double and no more. It charges and discharges together with the power station it's attached to, and has its own screen showing the remaining percentage and estimated time, plus an internal compartment to store the cables.
It's designed for anyone who already has a DELTA 2 and wants more autonomy without replacing it. On its own it powers nothing: without the power station and the dedicated cable it stays a closed block of cells.
official manufacturer list price — on nominal capacity
| Parameter | Value | Source |
|---|---|---|
| Weight | 9.5 kg (20.9 lb) | manufacturer website |
| Compatible models | EcoFlow DELTA 2 | Declared by the brand |
| Nominal capacity | 1.024 kWh | Declared by the brand |
| Cell chemistry | LFP (lithium iron phosphate) | Declared by the brand |
| Expandable | Yes | Declared by the brand |
| Maximum expanded capacity | 2.048 kWh | Declared by the brand |
| Maximum charge power | 1.024 kW | Declared by the brand |
| Rated cycles | 3000 cicli | Declared by the brand |
| Capacity at end of cycle life | 80 % | Declared by the brand |
| Warranty | 5 anni | Declared by the brand |
| Official list price | 599 € | Declared by the brand |
| Usable capacity | — | Not declared |
| Depth of discharge | — | Not declared |
| Cell supplier | — | Not declared |
| Continuous output | — | Not declared |
| Peak output | — | Not declared |
| Peak duration | — | Not declared |
| AC outlets | — | Not declared |
| Fastest USB-C | — | Not declared |
| USB-A ports | — | Not declared |
| USB-C ports | — | Not declared |
| 12 V outputs | — | Not declared |
| 24 V outputs | — | Not declared |
| 0–80% charge time | — | Not declared |
| Maximum solar input | — | Not declared |
| Backup power | — | Not declared |
| Switchover time | — | Not declared |
| Guaranteed throughput | — | Not declared |
| Guaranteed remaining capacity | — | Not declared |
| Round-trip efficiency | — | Not declared |
| Standby consumption | — | Not declared |
| Ingress protection | — | Not declared |
| Mounting | — | Not declared |
| Minimum temperature | — | Not declared |
| Maximum temperature | — | Not declared |
| Cell heating | — | Not declared |
| Noise level | — | Not declared |
| Wheels and handle | — | Not declared |
| Works without internet | — | Not declared |
| Local control | — | Not declared |
| Open protocols | — | Not declared |
| Home Assistant integration | — | Not declared |
| Where the data is hosted | — | Not declared |
| Remote updates | — | Not declared |
| App required for setup | — | Not declared |
| Declared standards | — | Not declared |
The rest of the data comes from 2 pages on the manufacturer's site, cited row by row in the table above.
A manual or a datasheet counts as a source even when the original file is hosted elsewhere: what matters is the document, not the server. Where that happens, it is stated above.
These numbers are calculated, not stated: they have no source to cite, they have a formula you can redo. The price used is the manufacturer's list price, which is stable and the same in every country — not a shop's price on the day.
