BYD home battery review: specs, warranty and downsides
The answer first: BYD Battery-Box comes as HVS (5.12–12.8 kWh) and HVM (8.28–22.08 kWh), with a 10-year warranty that ends at 70% or a throughput figure [SB-S073, SB-S057, C]. Check the model on your quote: the HVM listing ends 5 December 2026, while HVM+ runs to 31 December 2027 [SB-S073, C]. No dated installer price found, so get quotes.
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On this page: What it is · Prices · Downsides · Who it's not for · Ask your installer
What it is
High-voltage stacks: HVS in 2.56 kWh modules, round-trip 96% or more [SB-S056, C]; HVM in larger modules. BYD sells the battery only: its Australian datasheet says it works with "leading 1 and 3 phase high voltage battery inverters" from other brands [SB-S203, C]. On the installer compatibility list we hold, a Fronius Symo GEN24 Plus takes 4–8 HVM modules and a Primo GEN24 Plus 4–7 [SB-S203, C].
| Spec | BYD |
|---|---|
| Usable kWh | HVS 5.12–12.8; HVM 8.28–22.08 [SB-S073, C] |
| Max size | HVM 22.08 kWh per stack [SB-S203, C]; for more than one stack, ask the installer |
| Inverter setup | battery only; pairs with compatible high-voltage hybrids, e.g. Fronius GEN24 Plus [SB-S203, C] |
| Backup | set by the inverter you pair it with, not by BYD [SB-S203, E]; ask what your inverter backs up |
| Warranty | 10 yrs; 70% or minimum throughput, first (HVS 12.8: 38.53 MWh; HVM 22.1: 68.31 MWh), installed from 1 Nov 2024 [SB-S057, C] |
| CEC listed until | HVS 17 Jan 2027; HVM 5 Dec 2026; HVM+ 31 Dec 2027 [SB-S073, C] |
Prices
| Size | Installed price (seller, as at) | Model |
|---|---|---|
| HVS 12.8 kWh | No dated price yet | Battery-Box Premium HVS 12.8 |
| HVM 13.8 kWh | No dated price yet | Battery-Box Premium HVM / HVM+ |
Installer pages we found are undated or show ranges, so we don't show numbers.
What the federal discount is worth. Our arithmetic, not a quote: installs from May to December 2026 earn 6.8 STCs per usable kWh up to 14 kWh, then 60% of that to 28 kWh and 15% to 50 kWh [SB-S036, SB-S001, C]. STCs last traded at $39.65 (30 Oct 2026); installers pass on a bit less [SB-S095, C]. The factor drops to 5.7 for installs from January 2027 [SB-S036, C]. The discount is set by the installation date [SB-S004, C]. It needs a CEC-listed, VPP-capable battery installed with solar by an SAA battery-endorsed installer [SB-S003, C]. The STC price moves, so your installer's figure will differ. Official rules: cer.gov.au and dcceew.gov.au. HVS 12.8 kWh: 87 STCs, about $3,450. HVM 22.1 kWh: 128 STCs, about $5,075 [SB-S036, SB-S001, SB-S095, E].
Downsides
- HVM listing ends 5 Dec 2026 [SB-S073, C]; check the listing on your install date.
- Throughput caps can end the warranty before 10 years on heavy cycling [SB-S057, C/E].
- Two companies' warranties: BYD covers the battery, your inverter maker covers the inverter [SB-S203, SB-S057, E].
- The AU datasheet we hold is version 1.1 from 2023 [SB-S203, C]; ask for the current one.
Who it's not for
BYD is not for you if:
- your quote is for HVM (not HVM+) and the install is after 5 Dec 2026 without a renewed listing [SB-S073, E].
- you want a dated published price before talking to installers.
It suits homes that already have, or are buying, a compatible high-voltage hybrid such as a Fronius GEN24 Plus [SB-S203, C].
Ask your installer
- HVS, HVM or HVM+, and its CEC listing end date [SB-S073].
- Which inverter it pairs with, whether that inverter is on BYD's compatibility list for your module count, and what backup it gives [SB-S203].
- The STC count and the install date it assumes [SB-S004].
Next step: get quotes
Ask at least two accredited installers for a written quote that shows the model, usable kWh and the certificate count.
Head to head: we compare BYD with Sigenergy on inverters, listing dates and warranty caps. The six brands' specs and warranty caps sit side by side on our home page, so it's worth checking the others before you get BYD quotes.
Rules checked 3 November 2026. Next scheduled check: before 1 January 2027 (STC step-down), and monthly for WA and NSW.