Capacity is the number everyone quotes. It is the wrong one.
Power stations are sold on watt-hours. Bigger number, more marketing. But two 2042 Wh stations in this set, Jackery Explorer 2000 v2 and Jackery Explorer 2000 Plus, weigh 39.5 lb and 61.5 lb. Same capacity,22 extra pounds. On the chart that is the difference between a steep line from the origin and a shallow one; the slope is energy density, and it is the number that decides whether the thing actually goes camping or lives next to the wall forever.
What the spread looks like
Across 18 stations, density runs 26.5 to 51.7 Wh per pound, with the middle of the field near 36. Jackery Explorer 2000 v2 tops it at51.7; Bluetti EB3A sits at the bottom near 26.5. That is close to a 2x range in how much energy you carry per pound, hiding behind capacity numbers that look interchangeable on a shelf.
Small stations carry more dead weight
The low end of the density range is dominated by the smallest units. Every station pays a fixed tax in housing, the AC inverter, ports, and a display, and that tax is a larger fraction of a 300 Wh station than a 2000 Wh one. So the compact models people expect to be the most portable are often the least efficient per pound. Portability is real, but you are buying convenience, not density.
Chemistry is not the whole story
Nearly every station here uses LiFePO4, prized for cycle life and safety. The one exception on a different chemistry does not beat the LiFePO4 average on density, which is the tell: at this size, generation and packaging (how tightly the pack, inverter, and case are built) move Wh per pound more than the cell chemistry named on the box. Judge the finished product, not the chemistry label.
Methodology
Figures are manufacturer-stated capacity (Wh) and weight (lb) for the 18 portable power stations in the Slopsheets catalog as of 2026-07-22, with density derived as capacity divided by weight. We store no scraped or live-priced data; this is a spec-sheet aggregation, refreshed as the catalog updates.