A single-number ranking hides what is being optimised. Here there are two axes at a time, and the question «which are the best» is answered by those nobody beats on both measures.
On Cost per kWh, further left is better; on Nominal capacity, higher up. The coloured corner, “best zone”, is where both measures are good.
Filled in are the 2 products that no other beats on both measures. They are not «the best»: they are the ones nobody dominates.
Striped, paler points have at least one of the two measures without a verified source.
One sheet is missing, because it does not state both measures.
| Product | Cost per kWh · €/kWh | Nominal capacity · kWh | Verified |
|---|---|---|---|
| DJI Power Expansion Battery 2000 | 354 | 2.05 | Partly |
| BLUETTI B500K | 468.55 | 5.12 | Yes |
| BLUETTI B300K | 506 | 2.76 | Yes |
| EcoFlow DELTA 2 Max Smart Extra Battery | 536.62 | 2.05 | Yes |
| Jackery Battery Pack 2000 Plus | 537.99 | 2.04 | Yes |
| EcoFlow DELTA 3 Series Smart Extra Battery | 584.96 | 1.02 | Yes |
| EcoFlow DELTA 2 Smart Extra Battery | 584.96 | 1.02 | Yes |
| EcoFlow DELTA Pro 3 Smart Extra Battery | 610.11 | 4.10 | Yes |
| BLUETTI B210P | 697.21 | 2.15 | Yes |
| Anker SOLIX BP3800 | 702.86 | 3.84 | Yes |
| Anker SOLIX BP2600 | 781.25 | 2.05 | Partly |
