Stored kilowatt-hours only pay back if the house uses them at night · review
An AC-coupled 1.92 kWh battery expandable to 11.52 kWh whose listing publishes both a conversion efficiency and a round-trip efficiency — the only one in this family that does.
The bottom line The sparest sheet in this family and, on one line, the most useful: it publishes a round-trip efficiency, which is the figure that decides whether a tariff-driven battery pays for itself. Everything else about the pack — chemistry, cycles, power — is absent.
A 1.92 kWh AC-coupled module with six bullets, four of them a phrase long, and one of them more informative than most whole listings here.
A bidirectional DC/AC efficiency of 96.5 % and an AC round-trip efficiency of 86 %. Nothing else in this family publishes the second figure. It is what a stored kilowatt-hour costs: charge from the mains and take it back out, and roughly one unit in seven has gone.
This class of product is bought to move energy in time — from midday to evening, or from a cheap hour to an expensive one. Whether that pays depends on the round trip, not on the size of the pack. A maker that publishes it is inviting the comparison; most do not.
The chemistry. The cycle count. Any power rating in either direction. Three of the six specification lines on this page say the same thing: absent from the listing.
The battery and the mounting accessories, listed in the last bullet. That is worth noting on a product class where brackets are frequently a separate purchase.
German Amazon store quoted about 545 € when this page was compiled.
American, British, French, Italian and Spanish Amazon catalogues carry an entry for it, with nobody selling.
These figures are what Keepa reported on the day this page was last updated. Availability and pricing move without notice.
Prices quoted in this text were read on 16 September 2026. The live price is at the top of the page.
| Usable capacity | Nowhere in the listing — 1.92 kWh is published as capacity, expandable to 11.52 kWh |
|---|---|
| Charge and discharge power | Nowhere in the listing — no wattage is published |
| Chemistry | Nowhere in the listing — not named in any bullet |
| Cycle life | Nowhere in the listing |
| Inverter compatibility | AC-coupled, first bullet; no specific inverter is named |
| Published metering | App control is named, third bullet; the fifth bullet publishes a bidirectional DC/AC efficiency of 96.5 % and an AC round-trip efficiency of 86 % |
| Amazon reference | B0FSF3JMQP (same reference on 6 Amazon marketplaces) |
| EAN | 6975514333729 |
The first is the conversion stage alone, in one direction. The second is the full round trip: mains in, stored, mains out. The gap between them is what storing a kilowatt-hour actually costs, and publishing both is what makes it visible.
Because the arithmetic of charging cheaply and discharging at a peak only works if the round trip does not eat the difference. An 86 % round trip means roughly one unit in seven is lost between the two prices.
1600 Wh base, up to 8 kWh · 1600 W output · 3 MPPT, 2700 Wp solar · LiFePO4 · IP65 · AC-coupled · smart meter and tariff integration
An AC-coupled all-in-one balcony storage system with three MPPT trackers taking 2700 Wp, a 1600 W output, expansion to four packs, and integration with dynamic electricity pricing.
Best for: A household on a dynamic electricity tariff that already has roof PV and wants to stop exporting surplus.
≈ €448
1.92 kWh nominal · 2800 W solar across 4 MPPT · 1200–2300 W on two AC ports · LFP, 6000 cycles · IP65 · down to −20 °C · 26 cm wide
An AC-coupled 1.92 kWh LFP unit with four MPPT trackers taking 2800 W of solar, two mains ports rated 1200 to 2300 W, IP65 and stated operation to −20 °C.
Best for: A narrow indoor space beside an existing balcony installation, where four panel groups need managing separately.
≈ €549
1600 Wh base, expandable to 9.6 kWh · 2 MPPT, 1200 W solar (600 W per tracker) · 6000 cycles · IP65 · down to −20 °C · 10-year warranty
A balcony storage unit with two MPPT trackers taking 1200 W of solar, expandable to 9.6 kWh with five further packs, rated IP65 and stated to operate down to −20 °C.
Best for: A balcony with panels facing two different directions, where per-tracker limits matter more than total capacity.
≈ €399
