How we rank batteries
Public scoring methodology · Last updated August 2026
Commercial relationships never change a battery's score or ranking.
The scoring formula below is applied uniformly to every battery in our database — no manufacturer, installer, or advertiser can pay to move up in the rankings. The same battery gets the same score regardless of when or how you view it.
The six scoring categories
Each battery in our database is scored out of 100. The score combines six categories using the fixed weights shown below. When you complete the wizard, we recalculate each battery's score using your specific inputs (usage, solar, phase, backup, EV) — so "best pick" for a 4-person Melbourne family with an EV is not the same as "best pick" for a 2-person Sydney townhouse.
Financial value
- Installed price per usable kWh (net of federal + state rebates)
- Estimated payback years based on your household usage and tariff
- 10-year total cost of ownership (including inverter warranty gap risk)
- Retail-to-installer price gap (transparency of pricing)
Battery quality
- Cell chemistry (LFP > NMC for residential safety and cycle life)
- Cycle warranty (cycles-to-70%-capacity, higher is better)
- Throughput warranty (MWh guaranteed over 10 years)
- Round-trip efficiency (usable output ÷ input)
Manufacturer credibility
- Presence in the Australian market (years operating in AU)
- Local warranty support and RMA turnaround
- Financial stability of the parent company
- Volume of installs across CEC-accredited installers
Compatibility with your setup
- Works with your existing solar inverter (or requires replacement)
- Single-phase vs three-phase supply compatibility
- VPP participation (Amber, AGL, Origin, Tesla, EnergyLocals)
- EV charger integration + whole-home backup capability
Safety and compliance
- AS/NZS 5139:2019 certification (mandatory for AU install)
- IP rating (outdoor vs indoor install suitability)
- Battery Management System (BMS) certifications
- Fire-suppression / thermal-runaway protection design
User fit
- Right-sized for your daily kWh consumption (not over/under-spec)
- Matches your solar generation profile (avoid oversize battery for small solar)
- Suits future plans (EV, heat pump, additional solar)
- Backup coverage matches your household priorities
Personalisation
The weights above are fixed. What changes is the input data we feed into each category for your specific household:
- Your daily kWh usage— drives Financial value, User fit, and Compatibility.
- Your existing solar (or lack of it)— changes Compatibility scores and payback maths.
- Your address— determines eligible state rebates, install-labour rates, and travel surcharge.
- Your phase (single / three)— affects Compatibility and pricing.
- Your backup priority— a customer who wants whole-home backup gets different scores than one who just wants payback.
What is NOT part of the score
- Advertising spend by manufacturers.
- Brand recognition or marketing budget.
- Whether we "prefer" a brand — we don't. Rankings are algorithmic.
- Commercial partnerships of any kind — the score depends only on the six categories above.
Data sources
- Manufacturer datasheets (AS/NZS 5139 certification, cycle life, warranty, chemistry).
- Solar Victoria & CEC (Clean Energy Council) approved product list.
- Federal Battery Rebate Scheme (CBRS) 2026 rates.
- State rebate program terms (VIC Solar Homes, NSW PDRS/ESS, SA HBS, QLD Battery Booster).
- Australian wholesale battery distributor price sheets — used to derive underlying installer cost.
- Live customer inputs (your wizard answers) for personalisation.
Corrections
Spot a mistake in the scoring — a stale datasheet, a wrong warranty figure, or a factually incorrect ranking? Tell us at info@batterychoice.ai and we'll investigate publicly. This page will show a "last updated" date whenever the methodology or weights change.