What's actually buyable in Australia right now, what it costs in AUD per usable kWh, and the one thing most build threads leave out: new LiFePO4 is now close enough in price that the used-EV route has to earn its place.
Two honest answers, depending on what you're optimising for.
You enjoy the build, can capacity-test modules yourself, and can source cells under roughly A$120/kWh. Best value is in bigger banks (20 kWh+) where the BMS, contactors and enclosure costs get amortised, and in buying a written-off EV at salvage auction where the rest of the car can be parted out to recover A$2,000–4,000.
You want a battery that just works. A new 48 V LFP rack pack at A$180–270/kWh includes a BMS, a warranty and a safe chemistry. Once you add a BMS, fusing, enclosure, freight and an electrician to used NMC modules, the delivered cost per usable kWh is often higher than new LFP — as the calculator below shows.
Pick a sourcing route, set your target usable capacity, then adjust the assumptions. Everything is calculated live — the number that matters is dollars per usable kWh delivered, after age, depth of discharge, hardware and install.
Australia's second-life market is thin and ad hoc. Most used Leaf packs get bought by Leaf owners needing a replacement, not by off-gridders — so supply comes from classifieds, wreckers, salvage auctions and one or two specialist resellers.
~0.5 kWh, 7.6 V each. Sold in lots of 7–10 to build a 48 V string. No cell-level BMS in the module — you supply it. Check SOH with LeafSpy before paying, and capacity-test what you buy.
Tested, GST-inclusive, ships nationally. Also lists a BMW 530e 1.5 kWh pack at A$350 (≈A$230/kWh) and reclaimed NMC prismatics. Thin catalogue — you buy what's in stock this week.
Roughly A$100–200/kWh. Watch for packs sold as "faulty" that are actually one bad module. Gumtree, Facebook DIY battery groups and the AEVA forums are where these move.
Graysonline / Pickles. Often the best effective price once you sell doors, wheels, motor and inverter — but you need space, tools, and a way to move a 300 kg pack safely.
Cheap on paper, expensive landed. Dangerous-goods freight, biosecurity, and no local recourse if the pack arrives at 60% SOH. Only makes sense above ~20 kWh, if at all.
Complete with BMS, comms, warranty and full usable capacity. Installed whole-home systems run ~A$5,000+ for 5 kWh, but bare DIY rack packs are the real competitor to a used-EV build.
Nameplate pricing converted to a realistic delivered cost. The last column is the one to argue about.
| Route | Nameplate A$/kWh | Typical SOH | Usable fraction | Effective A$/usable kWh* | Watch out for |
|---|---|---|---|---|---|
| Leaf modules, private / eBay | 120–200 | 70–85% | ~62% | 190–320 | No BMS, unknown history, mixed generations |
| AU reseller (tested modules) | 190–230 | 80–90% | ~68% | 280–340 | Small stock, small modules, per-unit pricing |
| Whole used Leaf pack | 100–200 | 70–80% | ~60% | 165–335 | Faulty-pack risk; 350 V DC, not 48 V |
| Written-off EV (salvage) | 70–120 | 75–90% | ~66% | 105–180 | Freight, storage, HV safety, parting-out effort |
| New 48 V LFP rack pack | 180–270 | 100% | ~95% | 190–285 | Nothing much — this is the baseline |
Every one of these is routinely omitted from "I built a 48 V Leaf bank for cheap" videos.
An 80% SOH pack cycled to 80% DoD gives you 64% of its sticker capacity. That 24 kWh Leaf pack is ~15 kWh you can actually use — so the real price is ~1.4–1.6× the advertised $/kWh.
Leaf modules are bare cells in plastic. You need a proper BMS, contactors, pre-charge, fusing and a thermal plan — realistically A$500–1,500, and the engineering is on you.
Second-life NMC in a shed, unenclosed, on a hobby BMS, is a genuine thermal-runaway risk. LFP is the safer chemistry for anything attached to a house — used EV packs are overwhelmingly NMC.
AS/NZS 5139 governs battery energy storage, and any mains wiring must be done by a licensed electrician — DIY electrical work isn't permitted in Australia. A self-built NMC bank generally can't be certified, which can void insurance even off-grid. Ask your insurer before you buy cells.
All accessed October 2026. Retail prices are as listed at time of writing and move constantly.