Most plug-in hybrids sold in Australia have no capacity guarantee. The Sealion 6 does. BYD's warranty covers the battery in its DM plug-in hybrids the same way it covers its EVs — 8 years or 160,000 km with a 70% floor, transferable, backdated to every BYD sold here since August 2022. For a car class where the battery is usually the buyer's biggest unknown, that is a meaningful difference.
The packs Australia got
| Variant | Years | Battery (gross) | Electric range | Cycle |
|---|---|---|---|---|
| Essential / Dynamic / Premium | 2024–2026 | 18.3 kWh | 81–92 km | NEDC — not WLTP |
| Dynamic Extended Range | 2026 | 26.6 kWh | 140 km | NEDC — not WLTP |
Both ranges are quoted on the NEDC cycle, an older standard that typically runs 20–30% above what WLTP would show for the same car. Treat 81–92 km as roughly 60–70 km of real electric driving, and 140 km as something closer to 105–115 km. The 2026 Extended Range car has a substantially larger pack and is a different proposition for anyone whose commute would otherwise empty the smaller one every day.
Why the chemistry helps
The Sealion 6 uses BYD's Blade lithium-iron-phosphate chemistry, which tolerates full charging and deep cycling better than the nickel-based packs in most rival plug-ins. A PHEV lives a hard life — a pack that gets charged full and run flat most days — and LFP is the chemistry best suited to it. It also means "charged to 100% every night" is normal and expected on this car, not a warning sign.
What a PHEV test looks at
A plug-in pack does full charge-discharge cycles on a daily basis, so cycle count and cell balance tell you more than they do on an EV. The assessment reads the pack's own State of Health, the spread between cell groups, temperature behaviour and any stored or pending high-voltage fault codes. If one cell group is drifting from the rest, that is the early signal, and it shows up long before range noticeably falls.
What to check before you buy
Which pack — 18.3 or 26.6 kWh — and remember the ranges are NEDC
Measured State of Health against a published 70% floor
Cell voltage spread, which is where a PHEV pack shows its age first
How the previous owner charged it — nightly charging is fine on LFP; a car that was never plugged in has been a heavy hybrid
In-service date and odometer against 8 years and 160,000 km
Full terms: BYD battery warranty in Australia.
BYD Shark 6 · Mitsubishi Outlander PHEV · Book a test — $249
Battery capacities and NEDC ranges from BYD Australia. Warranty terms from BYD Australia's 2025 vehicle warranty document. Verified 15 September 2026.