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Performance & Value

S10 X 21

20.6 kWh · LFP · All-in-one · Three-phase

E3/DC

51/ 100

Average / Industry average

Global

LFPHigh Power 10kW+

The verdict. In our Performance & Value class, E3/DC S10 X 21 leads on safety & chemistry. Home-battery reliability is rarely independently verified, so judge on chemistry, safety certification and the backing company.

49thof 49 in Performance & ValueBottom quarterclass average 65.2
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The assessment

How it scores, by category

Capacity & Usability40
Power & Efficiency53
Longevity (verified)56
Safety & Chemistry61
Guarantee & Backbone43
Energy Ecosystem40

Market position

49thof 49 in Performance & ValueBottom quarter
515176

Our reading

S10 X 21 scores 51, placing 49 of 49 in the Performance & Value class against a class average of 65.2. Its strongest scoring dimension is safety & chemistry (61). Energy Ecosystem scores 40, the lowest pillar for this product. The class average on energy ecosystem is 51. Key specifications: LFP, 11 kW continuous output.

The data

Chemistry
LFP
Power
11kW
Round-trip
Not recorded
Cycle life
Not recorded
Technology architecture

All-in-one energy system

Architecture guide

Presents storage and power conversion as one integrated product or product platform.

Product role
Battery modules, inverter functions and controls are packaged as one purchasing architecture.
Published range
20.6 kWh
Phase
Three phase
Backup boundary
Installation-specific
Architecture describes the product boundary. It is not a system design or an equipment-pairing decision.

Capacity guarantee: minimum retained at year 10

20.6 kWhfull16.5at yr 10
708090100Rated capacity 100%Guaranteed floor 80.0%80.0%0yr2yr4yr6yr8yr10yr
Rated capacity (reference)Guaranteed floor: 80.0% 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. Capacity figure based on the sourced usable capacity of the base configuration; modular systems scale with additional modules.

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 S10 X 21 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 uses the seven-module configuration. Battery output, inverter AC output and replacement-power behavior are published separately. Scored model: S10 X 21 with seven battery modules · checked 2026-08-06. Evidence.

Sources & references · checked 2026-08-06

Strong evidence coverage

12 of 12 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. Series benchmark source checked
  3. DE market evidence 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.