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Performance & Value

eVault MAX 18.5

18.43 kWh · LFP · DC-coupled

Fortress PowerReleased 2021

70/ 100

Very good

Global

LFP100% Usable97%+ Efficiency

The verdict. In our Performance & Value class, Fortress Power eVault MAX 18.5 leads on capacity & usability. Home-battery reliability is rarely independently verified, so judge on chemistry, safety certification and the backing company.

11thof 45 in Performance & ValueTop quarterclass average 65.4
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The assessment

How it scores, by category

Capacity & Usability90
Power & Efficiency82
Longevity (verified)62
Safety & Chemistry66
Guarantee & Backbone64
Energy Ecosystem62

Market position

11thof 45 in Performance & ValueTop quarter
547075

Our reading

eVault MAX 18.5 scores 70, placing 11 of 45 in the Performance & Value class against a class average of 65.4. Its strongest scoring dimension is capacity & usability (90), above the class average of 86. Key specifications: LFP, 98% round-trip efficiency, 9.2 kW continuous output.

The data

Chemistry
LFP
Power
9.2kW
Round-trip
98%
Cycle life
8,000cycles

Blackout protection

58 / 100#44 of 55 batteries
fleet low 46median 67fleet high 100
No backupGrid-forming

Whole-home (via hybrid inverter)

Continuous power
9.2kW
Switchover
>100ms / undisclosed
AC terminal protection
Not specified

The blackout score is a standalone benchmark of outage resilience only - it re-weights sourced specs already scored in this product’s pillars (backup tier, switchover, surge strength, backup power, off-grid recharge) and never affects the overall score. Dots show the full battery fleet; the marker is this product.

System decision

Australian system fit

Only exact, manufacturer-named Australian paths are shown. A shared brand, product family or output rating is not proof of compatibility.

Evidence state

Exact pairing not recorded

Exact pairing not recorded

No exact manufacturer-named inverter, battery or integrated-system pairing is recorded for Australia. This is a documentation state, not a finding that the product cannot be used in a system.

A documented relation does not establish site sizing, network approval, protected-load design, firmware state or installer acceptance. When no exact relation is recorded, compatibility remains unestablished in this catalogue.

Before you buy
Local positionUse a market view to check local availability, approvals and warranty scope.
Ask the installerWhat usable capacity, backup power and warranted operating conditions will the installed eVault MAX 18.5 configuration deliver?

Verification & sources

Market context

Global evidencechange in the site menu

Global benchmark. This scorecard is benchmarked globally. A global score does not imply local availability, certification, warranty coverage, or installer compatibility.

Benchmark anchor. The score is fixed to the single 18.43 kWh cabinet; parallel expansion to 20 cabinets does not change the scored configuration. Scored model: eVault MAX 18.5 single cabinet · checked 2026-08-04. Evidence.

Sources & references · checked 2026-08-05

Strong evidence coverage

30 of 30 scored criteria link directly to a published source.

Values marked estimated, derived, or not found remain visible on the audit sheet and do not carry the same evidential weight as a linked source. Coverage measures direct links, not an independent guarantee that a claim is correct.

Evidence timeline

Recorded verification events for this scorecard. These are evidence checks, not historical score snapshots.

  1. Core scorecard evidence checked
  2. US market evidence checked
  3. Series benchmark source checked

Scored by Solar Analytica Research

Further reading from Signals

Stay across the benchmark.

New scorecards, score changes and market signals, published as they happen.