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PLACEHOLDERNot a representation of the product
Performance & Value

eVault MAX 18.5

18.43 kWh · LFP · DC-coupled

Fortress PowerReleased 2021

71/ 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 63 in Performance & ValueTop quarterclass average 63.4
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The assessment

How it scores, by category

Capacity & Usability90
Power & Efficiency82
Longevity (verified)65
Safety & Chemistry66
Guarantee & Backbone64
Energy Ecosystem64

Market position

11thof 63 in Performance & ValueTop quarter
487176

Our reading

eVault MAX 18.5 scores 71, placing 11 of 63 in the Performance & Value class against a class average of 63.4. Its strongest scoring dimension is capacity & usability (90), running 7.3 points above the class average on this dimension. 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
Technology architecture

DC-coupled battery

Architecture guide

Stores DC energy and relies on system power electronics outside the battery product for household AC.

Product role
The published battery record covers the storage stack, controller and stated capacity range.
Published range
18.43 kWh
Phase
Not recorded
Backup boundary
Installation-specific
Architecture describes the product boundary. It is not a system design or an equipment-pairing decision.

Usable capacity

100% of this battery’s nominal capacity is usable, 18.43 kWh in the scored configuration.

18.43 kWh usableScored configuration: eVault MAX 18.5 single cabinet.

No reserve is withheld at the stated depth of discharge.

At a sourced 100% depth of discharge the usable and nominal figures are the same number, so no separate nominal capacity is stated.

Usable capacity sourceDepth-of-discharge source

Blackout protection

58 / 100#55 of 78 batteries
fleet low 40median 65fleet 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.

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.

Australia buyer evidence

Australian warranty decision

0 product records

Read the Australian warranty as a claim pathway: the headline term is separate from remedy, labour, freight, site work, transfer and registration conditions.

No available Australian warranty decision record is published for this product. No coverage is inferred.

Sources & references · checked 2026-08-05

Strong evidence coverage

31 of 31 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.

Record revision. eVault Max datasheet as modified 17 July 2026, warranty effective 1 February 2022, installation manual current edition

Evidence timeline

Recorded verification events for this scorecard. These are evidence checks, not historical score snapshots. No change to this product record has been published since the change ledger opened on 2026-08-16.

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

Evidence record (JSON)

Scored by Solar Analytica Research

Further reading from Findings

Stay across the benchmark.

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