Ranked by math. Not by us.
The ranking
We rank by €/Wh — price in euros divided by usable capacity in watt-hours. For each model, we use the cheapest in-stock offer across the marketplaces we cover. Cheapest wins. Math has no preferences.
Why €/Wh and not €/mAh
mAh comparisons only make sense within a single voltage class. A 10 Ah 12 V battery and a 10 Ah 24 V battery store very different amounts of energy. Wh is voltage-normalised energy. It lets us compare across formats fairly.
Marketplaces we cover
Amazon.de, eBay.de, and AliExpress in V0. More as we grow.
Data freshness
Prices are checked manually on a weekly cadence. Every offer carries the date we last verified it. Markets move; the site updates as we refresh the catalog.
What we don't do
- Paid placements
- "Editor's picks" disguised as rankings
- Including out-of-stock offers in the best-price calculation
Browse the current power station rankings.