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BYD · Home battery model

Battery-Box H 6.4

BYD Battery-Box H 6.4 is a superseded first-generation high-voltage LFP battery with five 1.28 kWh modules and 6.4 kWh usable energy.

Specifications

SpecificationValue
Usable capacity (kWh)6.40
Cell chemistryLFP
Maximum continuous power (kW)6.40 in the manufacturer brochure
Peak power (kW)12.80 for 30 seconds in the manufacturer brochure
Round-trip efficiency (%)at least 95.3 in the manufacturer brochure
Scalablefive to nine modules in the European brochure; the wider manual also documented four-module H 5.1
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)18.2 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Battery-Box H 6.4 is a superseded high-voltage battery from BYD’s first-generation Battery-Box H range. Its five B-Plus H 1.28 modules are connected in series and provide 6.40 kWh usable energy. It predates the later Premium HVS and HVM families.

Battery-side figures

The manufacturer brochure gives 6.40 kW maximum output and 12.80 kW peak for 30 seconds. Nominal voltage is 256 V and the operating range is 200 to 282 V. It identifies LFP cells and states at least 95.3% battery round-trip efficiency under its test conditions.

The brochure lists a 580 by 894 by 380 mm enclosure weighing 148 kg. A later V5.0 manufacturer manual gives the same dimensions but 143 kg, so the product version and label should be used where lifting or structural figures matter. Both documents state IP55 and operation from -10°C to 50°C, with derating below 12°C.

Inverter and expansion context

H 6.4 was a DC battery for a compatible external inverter. Its output did not guarantee the same AC power at the property. Backup also required the inverter and the wider changeover, protection and earthing arrangement.

The European brochure describes H 6.4 through H 11.5, while BYD’s broader user manual also includes the four-module H 5.1. Permitted module counts depended on the inverter. The brochure described parallel towers as forthcoming, so parallel capability should not be assumed for installed equipment.

Original warranty and lifecycle

The 2018 European residential terms covered H 6.4 for ten years, with 60% retained usable energy or 18.2 MWh throughput, whichever limit arrived first. Those terms apply only where the territory, sale date, installation and other conditions match the battery.

The original H range is absent from BYD’s current product overview and 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.