RCT Power Battery 5.7 vs SMA Home Storage 3.2
Technical comparison · High voltage
SMA Home Storage 3.2 works only with the single-phase SMA Sunny Boy Smart Energy inverter, while RCT Power Battery 5.7 is declared for RCT Power Storage DC inverters. The choice therefore starts from the inverter, not the battery. If that is still open, the deciding factor is where the battery has to go.
| Parameter | ||
|---|---|---|
| In brief | ||
| Usable capacity | 5.18 kWh | 3.28 kWh |
| Cell chemistry | LFP (lithium iron phosphate) | LFP (lithium iron phosphate) |
| Weight | 78 kg | 38 kg |
| Dimensions (W×D×H) | 34 × 34 × 83 cm | 61 × 21.46 × 48.3 cm |
| How long it lasts | ||
| Battery life cycles | 3650 cicli | 730 cicli |
| The limit that runs out first | anni di garanzia | anni di garanzia |
| Rated cycles | — | 8000 cicli |
| Capacity at end of cycle life | — | 60 % |
| Warranty | 10 anni | 2 anni |
| Guaranteed throughput | — | 23.616 MWh |
| Guaranteed remaining capacity | 80 % | 60 % |
| The numbers | ||
| Energy density | 66.4 Wh/kg | 86.3 Wh/kg |
| Identity | ||
| Use tier | F3 — Flat-sized (3–8 kWh) | F3 — Flat-sized (3–8 kWh) |
| Category specs | ||
| Depth of discharge | 90 % | 100 % |
| Expandable | Yes | Yes |
| Maximum expanded capacity | — | 16.4 kWh |
| Battery voltage | 230 V | 96 V |
| Declared compatible inverters | RCT Power Storage DC (6.0/8.0/10.0 LAN, 12.0): intervallo di tensione lato batteria 120-600 V dichiarato dall'inverter, entro cui rientra questa taglia (230 V nominali, 180-260 V di range). | Compatibile solo con l'inverter monofase SMA Sunny Boy Smart Energy, che con questo modulo singolo supporta da 1 a 4 moduli SMA Home Storage. Non compatibile con il trifase Sunny Tripower Smart Energy, che richiede almeno 2 moduli. Non retrofittabile sui vecchi Sunny Boy Storage (SBS2.5-1VL-10, SBS3.7-10-SBS6.0-10) né con inverter di altri marchi. |
| Round-trip efficiency | — | 94.5 % |
| Standby consumption | 5 W | 2 W |
| Ingress protection | ip42 | IP65 |
| Mounting | Floor standing | Wall mounted |
| Minimum temperature | 5 °C | -10 °C |
| Maximum temperature | 40 °C | 50 °C |
| Local control | None | — |
| Remote updates | — | Can be disabled |
| Declared standards | CE, UN 38.3, IEC 62619 | CE, UN 38.3, IEC 62619, IEC 62477, VDE 2510-50 |
The differences that matter
- Matching inverter: RCT Power Storage DC versus only the single-phase Sunny Boy Smart Energy → the inverter is chosen before the battery.
- Warranty: 10 years versus 2 → with the RCT the cover lasts through most of the system's useful life, with the SMA only the first two years.
- Weight and mounting: 78 kg on the floor versus 38 kg on the wall → this changes which room suits and how hard the installation is.
- Environment: IP42 and 5 °C minimum versus IP65 and -10 °C → only the SMA is declared for an unheated room.
Values declared by the manufacturer.
Which one to choose
Choose RCT Power Battery 5.7 if…
you have or will install an RCT Power Storage DC inverter and want 5.18 kWh usable in a single unit, with a 10-year warranty. The room must be sheltered and not freezing: protection is IP42, minimum operating temperature 5 °C, and at 78 kg the battery stands on the floor and cannot be hung on a wall.
Choose SMA Home Storage 3.2 if…
the system is a single-phase Sunny Boy Smart Energy and the battery has to go on a wall in a garage or unheated room: IP65, -10 to 50 °C, 38 kg. You start with one 3.28 kWh module and can grow to four (16.4 kWh); in return the warranty is 2 years and the battery only works with that SMA inverter.
Where to buy
The purchase links are the same as on the two product pages and don't influence the verdict. The product pages have the complete data.