back to plug-in ESS

Plug-in ESS

SUN-BK250

2.5 kW

DeyeReleased 2026

70/ 100

Very good

Global

LFP chemistryUPS-grade switchingIEC 62619 certified

The verdict. In our Plug-in ESS class, Deye SUN-BK250 leads on capacity & usability.

3rdof 8 in Plug-in ESSTop halfclass average 64.1
Ask Watt →

The assessment

How it scores, by category

Capacity & Usability100
Output Power73
Longevity (verified)58
Safety & Chemistry85
Guarantee & Backbone60
Connectivity & Ecosystem35

Market position

3rdof 8 in Plug-in ESSTop half
497077

Our reading

SUN-BK250 scores 70, placing 3 of 8 in the Plug-in ESS class against a class average of 64.1. Its strongest scoring dimension is capacity & usability (100), running 8.2 points above the class average on this dimension. Connectivity & Ecosystem scores 35, the lowest pillar for this product. The class average on connectivity & ecosystem is 49.

Dietreich Farquharson · review.solar

The data

Backup
2.5kW
Switching
<5ms
Cycle life
6000cycles
Warranty
10yr
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 SUN-BK250 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. Scored model: SUN-BK250 · checked 2026-08-23. Evidence.

Sources & references · checked 2026-08-23

Strong evidence coverage

22 of 22 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. Deye SUN-BK250 exact product page, 11 March 2026 datasheet and current corporate record, rechecked 2026-08-23

Change ledger

Product record history

40 changes to this record · 9 products changed in this update
  1. Record updated

    Grid-injection power (kW): Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  2. Record updated

    Ingress protection (outdoor): Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  3. Record updated

    Thermal & fire mitigation: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  4. Record updated

    Guarantee & Backbone pillar score

    Before
    51.5
    After
    60
    Primary datasheet
  5. Record updated

    VPP & grid services readiness

    Before
    VPP-capable, protocol ready
    After
    No VPP capability stated
    Primary datasheetUsable energy / DoD (%)
  6. Record updated

    Modularity & scalability: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  7. Record updated

    Cell balancing architecture: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  8. Record updated

    Smart home & IoT depth: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  9. Record updated

    Backup switching speed: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  10. Record updated

    Open protocol & API maturity

    Before
    Cloud API only
    After
    Proprietary / no documented API
    Primary datasheetUsable energy / DoD (%)
  11. Record updated

    Backup output power (kW): Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  12. Record updated

    VPP & grid services readiness: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  13. Record updated

    Usable energy / DoD (%): Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  14. Evidence added

    Source revision

    Before
    Not previously recorded
    After
    Deye SUN-BK250 exact product page, 11 March 2026 datasheet and current corporate record, rechecked 2026-08-23
    Primary datasheet
  15. Record updated

    Open protocol & API maturity: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  16. Record updated

    AU Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyestore.com/en-au; https://www.deyestore.com/en-au/blogs/deye-smart-ct-unlock-the-new-solar-storage-system/balcony-solar-power-plant-the-2026-buyers-guide
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html; https://www.deyestore.com/en-au
    AU market evidencePrimary datasheet+2 in JSON record
  17. Record updated

    Financial strength & warranty backing: Evidence sources

    Before
    After
    https://www.deyeinverter.com/about/; https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    Financial strength & warranty backingPrimary datasheet
  18. Record updated

    Open protocol & API maturity: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  19. Record updated

    Warranty degradation guarantee: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  20. Record updated

    Thermal & fire mitigation: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  21. Record updated

    Cycle life (cycles to stated EOL): Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  22. Record updated

    Warranty assurance: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  23. Record updated

    Smart home & IoT depth: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  24. Record updated

    Operating temperature range: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  25. Record updated

    Cell chemistry: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  26. Record updated

    Warranty degradation guarantee: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  27. Record updated

    Cell balancing architecture: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  28. Record updated

    Self-heating capability: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  29. Record updated

    Connectivity & Ecosystem pillar score

    Before
    51.4
    After
    35
    Primary datasheet
  30. Record updated

    Safety certification: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  31. Record updated

    Manufacturing track record: Evidence sources

    Before
    After
    https://www.deyeinverter.com/about/; https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    Financial strength & warranty backingPrimary datasheet
  32. Record updated

    Manufacturing track record

    Before
    10-15 years
    After
    15+ years, field-proven
    Financial strength & warranty backingPrimary datasheet
  33. Record updated

    Source

    Current text
    checked: 2026-08-23; source revision: Exact SUN-BK250 product page and 11 March 2026 datasheet, rechecked 2026-08-23; source url: https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf

    The previous text is not reproduced here: both versions run to a full research paragraph. Both are in the JSON record linked below.

    Primary datasheet
  34. Record updated

    Financial strength & warranty backing

    Before
    Mid-tier private, no distress signals
    After
    Stable / listed
    Financial strength & warranty backingPrimary datasheet
  35. Record updated

    VPP & grid services readiness: Evidence status

    Before
    sourced
    After
    reviewed_absence
    Primary datasheetUsable energy / DoD (%)
  36. Record updated

    Global score

    Before
    70.5
    After
    69.5
    Primary datasheet
  37. Record updated

    Ranges

    Current text
    checked: 2026-08-23; market: global; max: 2.5; min: 2.5; range label: 2.5 kW; source revision: Exact SUN-BK250 product page and 11 March 2026 datasheet, rechecked 2026-08-23; source url: https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; unit: kW

    The previous text is not reproduced here: both versions run to a full research paragraph. Both are in the JSON record linked below.

    Primary datasheet
  38. Record updated

    Energy density / footprint: Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  39. Record updated

    Warranty period (yrs): Evidence sources

    Before
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)
  40. Record updated

    Warranty assurance: Evidence sources

    Before
    After
    https://www.deyeinverter.com/deyeinverter/2026/03/11/%E3%80%90B%E3%80%91Datasheet_SUN-BK80-250-2.56KWH-EU-AM4-18-32L_20260311_en.pdf; https://www.deyeinverter.com/product/hybrid-ess/sunbk-80250-2-56kwheuam418l-32l.html
    Primary datasheetUsable energy / DoD (%)

This is review.solar's publication history. It does not claim the product changed on the recorded date, and it excludes compatibility, system pairing, installation suitability and relative leaderboard prose. Open the complete JSON record.

Evidence timeline

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

  1. Core scorecard evidence checked
  2. AU market evidence checked
  3. Series benchmark evidence checked
  4. Plain-language warranty summary checked

Evidence record (JSON)

Scored by Solar Analytica Research

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