Capacity, output, expansion, UPS, charging and longevity. Rule score: 96/100.
Normalized comparison
RIVER 3 Plus vs 521
Green cells mark a meaningful category leader. Ties are shown as shared leaders.
Weight, energy density, charge speed, size and output. Rule score: 48/100.
Solar input, capacity, charging, longevity and weight. Rule score: 88/100.
| Specification | EcoFlow RIVER 3 Plus | Anker 521 |
|---|---|---|
| Capacity | 286 Wh | 256 Wh |
| Estimated usable | 243 Wh | 218 Wh |
| Continuous output | 600 W | 200 W |
| Surge output | 1,200 W | 450 W |
| AC outlets | 3 | 2 |
| Battery chemistry | LiFePO₄ | LiFePO₄ |
| Cycle life | 3,000 cycles | 3,000 cycles |
| AC full charge | 1 hr | 4.1 hr |
| Solar input | 220 W | 120 W |
| Weight | 10.4 lb | 8.2 lb |
| UPS | 10 ms | No |
| Expandable | Yes · 858 Wh max | No |
| Warranty | 5 years | 5 years |
| MSRP reference | $299 | — |
| Where to buy | Check price at manufacturer · EcoFlow USExact product listing at EcoFlow US — availability may change Check Price on Amazon.comExact product listing at Amazon US — availability may change | Check price at manufacturer · Anker SOLIX USExact product listing at Anker SOLIX US — availability may change Check Price on Amazon.comExact product listing at Amazon US — availability may change |
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