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Performance & Value

SimpliPHI 6.6

19.95 kWh · LFP · DC-coupled

Briggs & StrattonReleased 2024

72/ 100

Very good

Global

LFPUL9540A100% UsableHigh Power 10kW+

The verdict. In our Performance & Value class, Briggs & Stratton SimpliPHI 6.6 leads on capacity & usability. Home-battery reliability is rarely independently verified, so judge on chemistry, safety certification and the backing company.

7thof 63 in Performance & ValueTop 10%class average 63.4
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The assessment

How it scores, by category

Capacity & Usability90
Power & Efficiency90
Longevity (verified)60
Safety & Chemistry77
Guarantee & Backbone69
Energy Ecosystem49

Market position

7thof 63 in Performance & ValueTop 10%
487276

Our reading

SimpliPHI 6.6 scores 72, placing 7 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. Energy Ecosystem (49) is the dimension with the most room to move. Key specifications: LFP, 96% round-trip efficiency, 13.98 kW continuous output.

The data

Chemistry
LFP
Power
13.98kW
Round-trip
96%
Cycle life
Not recorded
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
19.95 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, 19.95 kWh in the scored configuration.

19.95 kWh usableScored configuration: SPHI-19.8-L0 three-module stack.

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

Capacity guarantee: minimum retained at year 10

65758595Rated capacity 100%Guaranteed floor 75.8%75.8%0yr2yr4yr6yr8yr10yr
Rated capacity (reference)Guaranteed floor: 75.8% at yr 10

No year-by-year capacity schedule is published for this product - the manufacturer guarantees only this end-of-term minimum, not a specific decline curve.

Blackout protection

79 / 100#7 of 78 batteries
fleet low 40median 65fleet high 100
No backupGrid-forming

Whole-home (via hybrid inverter)

Continuous power
13.98kW
Surge / motor-start
Surge rated
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 SimpliPHI 6.6 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 flagship three-module 19.95 kWh stack that Briggs & Stratton markets and the California lists carry as SPHI-19.8-L0. Scored model: SPHI-19.8-L0 three-module stack · checked 2026-08-04. Evidence.

Sources & references · checked 2026-08-07

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.

Record revision. Exact specification BS1547 dated 2026-04-22, retrievable governing ESS warranty effective May 2024, current product and support pages, conflicting later warranty locator and buyer-consequence boundaries reviewed 2026-08-07

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.