Knowledge base / Brands / BYD / Battery-Box H 7.7

BYD · Home battery model

Battery-Box H 7.7

BYD Battery-Box H 7.7 is a superseded first-generation high-voltage LFP battery with six 1.28 kWh modules and 7.68 kWh usable energy.

Specifications

SpecificationValue
Usable capacity (kWh)7.68
Cell chemistryLFP
Maximum continuous power (kW)7.68 in the manufacturer brochure
Peak power (kW)15.36 for 30 seconds in the manufacturer brochure
Round-trip efficiency (%)at least 95.3 in the manufacturer brochure
Scalablemodule count could be increased within the original H range, subject to inverter support
Maximum stack capacity (kWh)11.52 usable for one nine-module H tower
System couplinghigh-voltage DC battery for a compatible external inverter
Backup capablesystem-dependent; requires a compatible inverter and installed backup arrangement
Warranty (years)10 under the 2018 European residential terms
Warranty throughput (MWh)21.8 under the 2018 European terms
Warranty retained capacity (%)60 under the 2018 European terms, subject to the throughput limit
IP ratingIP55
Operating-temperature range (°C)-10 to 50, with derating below 12

Battery-Box H 7.7 is the six-module configuration from BYD’s superseded first-generation Battery-Box H family. Its exact usable-energy figure is 7.68 kWh. It is a different product from Premium HVS 7.7, despite the shared rounded size name.

Construction and output

Six B-Plus H 1.28 modules are connected in series. The manufacturer brochure states 7.68 kW maximum battery output and 15.36 kW peak for 30 seconds. Nominal voltage is 307 V and the operating range is 240 to 338 V.

The chemistry is LFP, with at least 95.3% battery round-trip efficiency under the historical document’s test conditions. The enclosure measures 580 by 1,014 by 380 mm. Its listed weight varies between manufacturer documents: 174 kg in the brochure and 168 kg in the V5.0 user manual. The installed product label should settle which figure applies.

Both documents state IP55 protection and an operating range from -10°C to 50°C, with derating below 12°C.

Compatibility and backup

Battery-Box H used a compatible external high-voltage inverter. AC power and backup behaviour depended on that inverter, its firmware and the rest of the electrical installation.

The wider family used four to nine modules, but supported counts varied by inverter. The brochure described direct parallel connection as forthcoming. It is not evidence that an installed H 7.7 can be paralleled or expanded without checking its applicable documents and firmware.

Original warranty and lifecycle

The 2018 European residential warranty gave H 7.7 a ten-year period, ending earlier if 21.8 MWh of throughput was reached. Its retained usable-energy threshold was 60%. Eligibility still depends on the sale date, territory and other conditions in that historical letter.

BYD’s current range no longer lists first-generation Battery-Box H products, so H 7.7 is recorded as superseded.

Brand

BYD

Reference type

Home battery model

Last reviewed

23 Jul 2026

Current status

Superseded product; relevant to installed systems and replacement identification.