BYD Battery-Box Premium HVM 8.3 vs RCT Power Battery 11.5
Technical comparison · High voltage
Two high-voltage LFP home batteries, and the first question is the inverter you already own: BYD lists sixteen compatible brands, while the RCT data covers only the manufacturer's own Storage DC series. If the inverter is not a constraint, the choice comes down to about 2 kWh of capacity against how sheltered the installation room is.
| Parameter | ||
|---|---|---|
| In brief | ||
| Usable capacity | 8.28 kWh | 10.37 kWh |
| Cell chemistry | LFP (lithium iron phosphate) | LFP (lithium iron phosphate) |
| Weight | — | 150 kg |
| Dimensions (W×D×H) | 58.5 × 29.8 × 99.5 cm | 34 × 34 × 152 cm |
| How long it lasts | ||
| Battery life cycles | 3094 cicli | 3650 cicli |
| The limit that runs out first | energia garantita | anni di garanzia |
| Rated cycles | 3650 cicli | — |
| Warranty | 10 anni | 10 anni |
| Guaranteed throughput | 25.62 MWh | — |
| Guaranteed remaining capacity | 60 % | 80 % |
| The numbers | ||
| Energy density | — | 69.1 Wh/kg |
| Identity | ||
| Use tier | F4 — House-sized (8–20 kWh) | F4 — House-sized (8–20 kWh) |
| Category specs | ||
| Depth of discharge | 100 % | 90 % |
| Expandable | Yes | Yes |
| Maximum expanded capacity | — | 23 kWh |
| Battery voltage | 153.6 V | 461 V |
| Declared compatible inverters | Sedici marchi nell'elenco ufficiale: Fronius, GoodWe, Viessmann, KOSTAL, SMA, Sungrow, GE, KACO, KACO NH, Ingeteam, Solis, Canadian Solar, Deye, Solplanet, Western CO, Sosen. Per ciascun modello l'elenco dà il numero di moduli ammessi e la versione minima del firmware. | 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 (461 V nominali, 360-520 V di range). Questa è la taglia abbinata alla Storage DC 10.0 LAN nel sistema misurato dalla HTW. |
| Round-trip efficiency | 96 % | — |
| Standby consumption | — | 5 W |
| SPI index (HTW Berlin) | — | 96.4 % |
| HTW test power class | — | 10 kW class |
| HTW test edition | — | Stromspeicher-Inspektion 2026 |
| Ingress protection | IP55 | ip42 |
| Mounting | Floor standing | Floor standing |
| Minimum temperature | -10 °C | 5 °C |
| Maximum temperature | 50 °C | 40 °C |
| Works without internet | Fully | — |
| Local control | Local network | None |
| Open protocols | CAN bus | — |
| App required for setup | Yes | — |
| Declared standards | CE, UN 38.3, IEC 62619, VDE 2510-50 | CE, UN 38.3, IEC 62619 |
The differences that matter
- Inverters: sixteen brands in the official list vs the RCT Power Storage DC series → with an inverter from another maker, the RCT battery is not among the declared pairings.
- Usable capacity: 8.28 vs 10.37 kWh → about 2 kWh more to shift from daytime to evening.
- Operating conditions: IP55 and −10 to 50 °C vs IP42 and 5 to 40 °C → the RCT belongs in an indoor room that does not get cold.
- Warranty: 10 years on both, but BYD guarantees 60 % of capacity at the end and RCT 80 % → for the same years, RCT keeps more guaranteed capacity. Figures as declared by the manufacturers.
Which one to choose
Choose BYD Battery-Box Premium HVM 8.3 if…
A garage or outbuilding where the temperature can fall below 5 °C, with an inverter from the BYD list (Fronius, SMA, Sungrow, Deye or Kostal, among others). It keeps working fully without internet and can be read over the local network. The trade-off is less capacity and a lower guaranteed capacity at the end of the warranty.
Choose RCT Power Battery 11.5 if…
A house that already has an RCT Power Storage DC inverter (the pairing is the 10.0 LAN) and an indoor room that stays above 5 °C. The footprint is 34 × 34 cm at 152 cm tall, which suits a narrow corner. You give up local control and accept a lower ingress rating, IP42.
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.