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Fortress Power eSpire Nano FP-Nano-S8-O battery pack (40.96 kWh, 409.6 Vdc): Maker series photo: Fortress Power eSpire Nano FP-Nano-S8: the cover picture of Fortress Power's eSpire Nano Battery Guide, which applies to the FP-Nano-S8-O and FP-Nano-S12-O battery units; the same picture stands for both pack sizes. The closed battery cabinet from the front, on a white background; the title and notice text are left out. Figure from the manufacturer's document, page 1.
Photo 1 of 1. 1 photo · Image from fortresspower.com
Photo sources

Manufacturer and seller images. Configuration examples may include additional equipment.

Image source: Maker series photo: Fortress Power eSpire Nano FP-Nano-S8: the cover picture of Fortress Power's eSpire Nano Battery Guide, which applies to the FP-Nano-S8-O and FP-Nano-S12-O battery units; the same picture stands for both pack sizes. The closed battery cabinet from the front, on a white background; the title and notice text are left out. Figure from the manufacturer's document, page 1.

Fortress Power eSpire Nano FP-Nano-S8-O battery pack (40.96 kWh, 409.6 Vdc)

By Fortress PowerSKU not documented

Industrial batteryIndustrial cabinet409.6 V100 Ah
Evidence score31/100Missing details
No reviews · Write the first
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Basic specs40.96 kWhDischarge100 ACharge100 A$ / rated kWhUnavailableWarranty10 years70% capacity retentionLifetime productionNot publishedSizeUnknownCertificatesCEC · UL 9540 · UL 1973CEC listed · UL scope in details

Key specs

Units
Chemistry
LFP (Lithium Iron Phosphate)
Official datasheet
Sources

As printed.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Battery Type

Documented

Nominal energy
40.96 kWh
Official datasheet
Sources

As printed. The same table also prints a rounded "Rated Battery Capacity" of "40 kWh" for this pack.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Nominal Energy (kWh)

Documented

Nominal voltage
409.6 Vdc
Official datasheet
Sources

As printed.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Nominal Voltage

Documented

Rated capacity
100 Ah
Official datasheet
Sources

Printed as one figure shared by both packs; this pack's own configuration is printed as "1P128S" with 8 racks.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Nominal Capacity

Documented

Continuous discharge current
100 A
Official datasheet
Sources

Printed as one figure for charge and discharge, shared by both packs.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Max Discharge/Charge Current

Documented

Continuous charge current
100 A
Official datasheet
Sources

Printed as one figure for charge and discharge, shared by both packs.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Max Discharge/Charge Current

Documented

Operating voltage range
358.4 to 460.8 Vdc
Official datasheet
Sources

As printed.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Operating Voltage Range (Vdc)

Documented

Enclosure rating
IP55 (IP20 w/ indoor option)
Official datasheet
Sources

As printed, shared by both packs; the -I model designator is the indoor option.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: General Specifications table, Enclosure Degree of Protection

Documented

3 specs not documented yet: usable energy, cycle rating, dimensionsHelp fill in ›

All specs13
Chemistry
LFP (Lithium Iron Phosphate)
Official datasheet
Sources

As printed.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Battery Type

Documented

Nominal energy
40.96 kWh
Official datasheet
Sources

As printed. The same table also prints a rounded "Rated Battery Capacity" of "40 kWh" for this pack.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Nominal Energy (kWh)

Documented

Usable energy
Not documented
Nominal voltage
409.6 Vdc
Official datasheet
Sources

As printed.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Nominal Voltage

Documented

Rated capacity
100 Ah
Official datasheet
Sources

Printed as one figure shared by both packs; this pack's own configuration is printed as "1P128S" with 8 racks.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Nominal Capacity

Documented

Continuous discharge current
100 A
Official datasheet
Sources

Printed as one figure for charge and discharge, shared by both packs.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Max Discharge/Charge Current

Documented

Continuous charge current
100 A
Official datasheet
Sources

Printed as one figure for charge and discharge, shared by both packs.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Max Discharge/Charge Current

Documented

Operating voltage range
358.4 to 460.8 Vdc
Official datasheet
Sources

As printed.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: DC Battery table, Operating Voltage Range (Vdc)

Documented

Cycle rating
Not documented
Details

Fortress Power prints no rated cycle life for the eSpire Nano. The 8000 cycles appear only in the Warranty row of the data sheet's General Specifications ("10 years, 70% Retention with 8000 cycles"), a warranty term, now recorded as the warranty cycle limit. Revised on 16 October 2026: The recorded cycle life was the warranty term from the Warranty row, not a rated cycle life (PM, October 16, 2026).

Not documented

Lifetime production

Not published

Published claims and calculations are not independently tested lifetime output.

Published claims and calculations, not independent test results.

Documents

3 on file
  • PDF
    Fortress Power eSpire Nano Data Sheet (English)OfficialFortress Power, LLCOfficial datasheet
    Certificate & compliance claims (7)
    UL1973Manufacturer claim · battery packClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. Fortress Power also publishes an SGS Certificate of Compliance (SGSNA/26/SZ/00137U) listing FP-Nano-S8-O by name, certified to ANSI/CAN/UL 1973, 3.0 Edition; this is Fortress Power's own copy of the certificate, and SGS's own directory was not checked, so current status is unknown.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    UL9540AManufacturer claim · unresolved document setClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    UL9540Manufacturer claim · unresolved document setClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    UL1741Manufacturer claim · unresolved document setClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    FCC Part 15Manufacturer claim · unresolved document setClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    IEEE 1547Manufacturer claim · unresolved document setClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    UN38.3Manufacturer claim · unresolved document setClaimedListed when checked

    Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

    Manufacturer document

    Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
    Source details
    Revision
    V.ESPIRENANO_042026
    Revision date
    Not stated

    Location: DC Battery table; General Specifications table

    Retrieved

    Fortress Power's own eSpire Nano datasheet (file eSpireNano_042026), linked from the eSpire Nano product page's Downloads tab, captured September 28, 2026. It prints recommended configurations pairing 30 kW and 60 kW inverters with 40 kWh and 60 kWh battery packs (and two packs of each in parallel), and a DC Battery table for the FP-Nano-S8 (-I/-O) and FP-Nano-S12 (-I/-O) packs.

    Archived copies

    Archived copy of a document published by Fortress Power, LLC. Copyright retained by the publisher; kept for reference and verification only, no endorsement implied. To ask for its removal, email legal@chargedreviews.com.

    Archived backup V.ESPIRENANO_042026 · 1.87 MB

    Archived copy, unaltered, kept as a record of what Fortress Power, LLC published. Original address: https://www.fortresspower.com/download/944/espire-nano/47949/fortress-power-espire-nano-data-sheet-english.pdf. Copyright and takedown

    Source first found
    This copy captured
    Archived
    File detailsOriginal source
    Pages
    2
    Embedded creation date
    Embedded modification date

    Embedded dates are file metadata, not independent proof of publication.

    SHA-256: e4e6340309699d9433281ab7f9ee24c093f3ce1dbae477f33b6bea0afdf06204

    Open
  • PDF
    Fortress Power Commercial and Industrial Battery Storage Product Limited Warranty (updated August 31, 2026)OfficialFortress Power, LLCOfficial warrantyAugust 31, 2026
    Source details
    Revision
    Updated August 31, 2026
    Revision date
    August 31, 2026

    Location: Individual Components table; Limited Warranty Period

    Retrieved

    Fortress Power's shared Commercial and Industrial battery storage warranty, updated August 31, 2026, linked from the eSpire Nano, eSpire Mini and eSpire 306 product pages, captured September 28, 2026. It names the eSpire Nano, eSpire Mini and eSpire 280/306/314 as covered component groups.

    Archived copies

    Archived copy of a document published by Fortress Power, LLC. Copyright retained by the publisher; kept for reference and verification only, no endorsement implied. To ask for its removal, email legal@chargedreviews.com.

    Archived backup Updated August 31, 2026 · 0.41 MB

    Archived copy, unaltered, kept as a record of what Fortress Power, LLC published. Original address: https://www.fortresspower.com/download/945/espire-mini/47883/fortress-power-ci-warranty.pdf. Copyright and takedown

    Source first found
    This copy captured
    Archived
    File detailsOriginal source
    Pages
    12
    Embedded creation date
    Embedded modification date

    Embedded dates are file metadata, not independent proof of publication.

    SHA-256: 5c3f9b0eb4aa954471ea00f517020ef86aabba41b8cb9060cbf9076a3166525e

    Open
  • WEB
    Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture)OfficialFortress Power, LLCOfficial product page
    Source details
    Revision
    Not stated
    Revision date
    Not stated

    Location: Product Information tab, Battery Specifications and General Specifications tables

    Retrieved

    Fortress Power's own eSpire Nano product page, captured September 28, 2026, under its Commercial & Industrial C+I Products navigation. Its Product Information tabs render the same inverter, battery and general specification tables printed in the eSpire Nano datasheet.

    Open

Archive and older revisions

Archive and older revisions0

Earlier revisions, archived captures and copies published by someone other than the manufacturer. Every one stays reachable.

Archived documents

Fortress Power eSpire Nano Data Sheet (English)

Archived copy of a document published by Fortress Power, LLC. Copyright retained by the publisher; kept for reference and verification only, no endorsement implied. To ask for its removal, email legal@chargedreviews.com.

Archived backup V.ESPIRENANO_042026 · 1.87 MB

Archived copy, unaltered, kept as a record of what Fortress Power, LLC published. Original address: https://www.fortresspower.com/download/944/espire-nano/47949/fortress-power-espire-nano-data-sheet-english.pdf. Copyright and takedown

Source first found
This copy captured
Archived
File detailsOriginal source
Pages
2
Embedded creation date
Embedded modification date

Embedded dates are file metadata, not independent proof of publication.

SHA-256: e4e6340309699d9433281ab7f9ee24c093f3ce1dbae477f33b6bea0afdf06204

SGS Certificate of Compliance SGSNA/26/SZ/00137U for Fortress Power eSpire Nano FP-Nano-S4-O through S12-O (outdoor), as published by Fortress Power

Archived copy of a document published by Fortress Power, LLC. Copyright retained by the publisher; kept for reference and verification only, no endorsement implied. To ask for its removal, email legal@chargedreviews.com.

Archived backup SGSNA/26/SZ/00137U · 0.97 MB

Archived copy, unaltered, kept as a record of what Fortress Power, LLC published. Original address: https://www.fortresspower.com/download/944/espire-nano/47947/fortress-power-espire-nano-ul1973-certification-outdoor.pdf. Copyright and takedown

Source first found
This copy captured
Archived
File detailsOriginal source
Pages
1
Embedded creation date
Embedded modification date

Embedded dates are file metadata, not independent proof of publication.

SHA-256: e344401805b14f78c2a9a6dcb851d179cc64a7704a4de609e16a73d26b95e44b

Fortress Power Commercial and Industrial Battery Storage Product Limited Warranty (updated August 31, 2026)

Archived copy of a document published by Fortress Power, LLC. Copyright retained by the publisher; kept for reference and verification only, no endorsement implied. To ask for its removal, email legal@chargedreviews.com.

Archived backup Updated August 31, 2026 · 0.41 MB

Archived copy, unaltered, kept as a record of what Fortress Power, LLC published. Original address: https://www.fortresspower.com/download/945/espire-mini/47883/fortress-power-ci-warranty.pdf. Copyright and takedown

Source first found
This copy captured
Archived
File detailsOriginal source
Pages
12
Embedded creation date
Embedded modification date

Embedded dates are file metadata, not independent proof of publication.

SHA-256: 5c3f9b0eb4aa954471ea00f517020ef86aabba41b8cb9060cbf9076a3166525e

Submit a document

Warranty

Territory
United States, United States Virgin Islands, Puerto Rico, and Mexico
Official warranty
Sources

As printed; all other United States territories are excluded.

Official warranty: Fortress Power Commercial and Industrial Battery Storage Product Limited Warranty (updated August 31, 2026) Rev Updated August 31, 2026 · August 31, 2026 · Checked · Earlier document

Location: Section 1, Limited Warranty

Documented

Warranty cycle limit
8,000 cycles
Official datasheet
Sources

Printed as "10 years, 70% Retention with 8000 cycles" in the Warranty row of the eSpire Nano data sheet, shared by both packs.

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: General Specifications table, Warranty

Documented

Capacity retention
70 %
Official datasheet
Sources

As printed, shared by both packs.

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: General Specifications table, Warranty

Documented

Warranty term
10 years
Official warranty
Sources

Fortress Power's Commercial and Industrial Battery Storage Product warranty names "eSpire Nano" with "Battery Capacity 40kwh/60kwh" and "PCS 30KW/60KW" among its covered C&I products, ending on the earlier of ten years from the Activation Date or the expiration of any purchased extended term. The datasheet separately prints "10 years, 70% Retention with 8000 cycles" in its own General Specifications table.

Official warranty: Fortress Power Commercial and Industrial Battery Storage Product Limited Warranty (updated August 31, 2026) Rev Updated August 31, 2026 · August 31, 2026 · Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Location: C&I Warranty, Individual Components table; datasheet General Specifications, Warranty

Documented

Sellers

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Price history

No seller price history.

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Your reviews · Review policy

Evidence score

31/100Missing details65% documented

The Evidence score uses the priorities you choose. It counts published documents, such as certificates and warranty terms, and it compares a documented figure with the best documented figure of the same kind. It does not count owner reviews, and it is not a verdict on product quality or on how many people have reviewed it. A low score can mean little is documented, or that a documented figure is below the best of its kind. Undisclosed data scores 0.

Missing details. This number counts only the evidence recorded so far. The source review for this product is not finished, or the maker has not disclosed enough, so the number can only go up.

Missing for this product: Warranty energy disclosure evidence needed; Lifetime / capacity evidence needed; Cell model disclosure evidence needed.

Industrial/Commercial ESS · High voltage · 30 to 100 kWh · Rated capacity

The warranty term and the lifetime energy are each scored against the best documented value for a home storage battery: a value earns its share of that best, times the weight. A documented value always earns points; an undisclosed one earns 0.

CertificatesUL1973 · UL9540A +6Manufacturer certificate20.89 / 45

46.43 evidence points · 45% weight

UL 1973: strongest qualifying evidence, counted once. Manufacturer-hosted certificate; independent issuer check remains open. Applies: UL 9540; UL 1973; CEC not assessed for commercial and industrial equipment in this catalog. UL 9540A is recorded but not scored: a thermal-runaway test method, recorded as a documented report and never scored as a listing.

46.43 / 100 × 45 = 20.89 points.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier documentOfficial certificate: SGS Certificate of Compliance SGSNA/26/SZ/00137U for Fortress Power eSpire Nano FP-Nano-S4-O through S12-O (outdoor), as published by Fortress Power Rev SGSNA/26/SZ/00137U · Checked · Earlier document
Warranty term10 years10 / 20

10 years · 20% weight

10 of 20 years, the best documented for a home storage battery (printed by the maker): Bioenno Power 6V 3Ah LiFePO4 Battery (PVC, BLF-0603W)

Fortress Power's Commercial and Industrial Battery Storage Product warranty names "eSpire Nano" with "Battery Capacity 40kwh/60kwh" and "PCS 30KW/60KW" among its covered C&I products, ending on the earlier of ten years from the Activation Date or the expiration of any purchased extended term. The datasheet separately prints "10 years, 70% Retention with 8000 cycles" in its own General Specifications table.

50 / 100 × 20 = 10 points.

Official warranty: Fortress Power Commercial and Industrial Battery Storage Product Limited Warranty (updated August 31, 2026) Rev Updated August 31, 2026 · August 31, 2026 · Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
Lifetime / capacityResearch pending0 / 20

No qualifying figure · 20% weight

Not published. No lifetime-production bonus.

Not documented. Undisclosed data scores 0.

Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Research pending, 0 points: Warranty energy disclosure, Cell model disclosure.

Computed from public specifications and evidence records. Warranty duration is not service quality; certificate evidence points are not a safety rating. Compatibility and installation limits still apply.

How it works Manufacturer? Submit documentation

Certificates

10 on fileCEC listedUL 9540 · claimedUL 1973 · cec reported · pack check pending

UL 1973: CEC reported · pack check pending

UL1973Finished battery pack / moduleClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. Fortress Power also publishes an SGS Certificate of Compliance (SGSNA/26/SZ/00137U) listing FP-Nano-S8-O by name, certified to ANSI/CAN/UL 1973, 3.0 Edition; this is Fortress Power's own copy of the certificate, and SGS's own directory was not checked, so current status is unknown.

Models: FP-Nano-S8

Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier documentOfficial certificate: SGS Certificate of Compliance SGSNA/26/SZ/00137U for Fortress Power eSpire Nano FP-Nano-S4-O through S12-O (outdoor), as published by Fortress Power Rev SGSNA/26/SZ/00137U · Checked · Earlier document
UL9540AProduct / system scope unresolvedClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Models: FP-Nano-S8

Standard as printed
UL9540A
Edition as printed
Not printed
What it covers
Product / system scope unresolved
Type
A fire-test report (UL 9540A is a test method, not a listing)
For a permit
A fire test. Useful supporting evidence, but it does not replace UL 9540.
Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UL9540Product / system scope unresolvedClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Models: FP-Nano-S8

Standard as printed
UL9540
Edition as printed
Not printed
What it covers
Product / system scope unresolved
Type
A listing to the energy storage system standard
For a permit
Permit offices commonly ask for this listing; local rules vary.
Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UL1741Product / system scope unresolvedClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Models: FP-Nano-S8

Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
FCC Part 15Product / system scope unresolvedClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Models: FP-Nano-S8

Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
IEEE 1547Product / system scope unresolvedClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Models: FP-Nano-S8

Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UN38.3Product / system scope unresolvedClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Models: FP-Nano-S8

Issued
Not stated
Valid from
Not stated
Expiry
Not stated
Issuer checked
Not checked
Official product page: Fortress Power eSpire Nano Commercial Energy Storage System product page (September 28, 2026 capture) Checked · Earlier documentOfficial datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UL 1973Product / system scope unresolvedClaimedListed when checked

Listed on the California Energy Commission Battery List (data unchanged since October 1, 2026; downloaded October 11, 2026) as Fortress Power LLC "FP-Nano-S8-I": UL 1973, certifying entity SGS, certificate date 2026-04-07, Ed. 3 : 2022, CEC listing date 2026-05-21. A state equipment list entry, not the certification body's own record.

Models: FP-Nano-S8-I

Issued
Not stated
Valid from
Apr 7, 2026
Expiry
Not stated
Issuer checked
Not checked
Issuer record: CEC Battery List, official spreadsheet (data unchanged since October 1, 2026; downloaded October 11, 2026) October 1, 2026 · Checked · Earlier document
CECProduct / system scope unresolvedClaimedListed when checked

Model FP-Nano-S8-I listed on the California Energy Commission Battery List (data unchanged since October 1, 2026; downloaded October 11, 2026) under Fortress Power LLC, as "FP-Nano-S8-I"; "FP-Nano-S8-O", CEC listing date 2026-05-21. Matched on the record's model alias "FP-Nano-S8-I". This is an equipment listing, not UL certification or complete-system approval.

Models: FP-Nano-S8-I

Issued
Not stated
Valid from
May 21, 2026
Expiry
Not stated
Issuer checked
Not checked
Issuer record: CEC Battery List, official spreadsheet (data unchanged since October 1, 2026; downloaded October 11, 2026) October 1, 2026 · Checked · Earlier document
CECProduct / system scope unresolvedClaimedListed when checked

Model FP-Nano-S8-O listed on the California Energy Commission Energy Storage System List (data unchanged since October 1, 2026; downloaded October 11, 2026) under Fortress Power LLC (brand Fortress Power), as "FP-Nano-S8-O", CEC listing date 2026-05-11. Matched on the record's model alias "FP-Nano-S8-O". This is an equipment listing, not UL certification or complete-system approval.

Models: FP-Nano-S8-O

Issued
Not stated
Valid from
May 11, 2026
Expiry
Not stated
Issuer checked
Not checked
Issuer record: CEC Energy Storage System List, official spreadsheet (data unchanged since October 1, 2026; downloaded October 11, 2026) October 1, 2026 · Checked · Earlier document
Datasheet & manual claims7
UL1973Manufacturer claim · battery packClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. Fortress Power also publishes an SGS Certificate of Compliance (SGSNA/26/SZ/00137U) listing FP-Nano-S8-O by name, certified to ANSI/CAN/UL 1973, 3.0 Edition; this is Fortress Power's own copy of the certificate, and SGS's own directory was not checked, so current status is unknown.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UL9540AManufacturer claim · unresolved document setClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UL9540Manufacturer claim · unresolved document setClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UL1741Manufacturer claim · unresolved document setClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
FCC Part 15Manufacturer claim · unresolved document setClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
IEEE 1547Manufacturer claim · unresolved document setClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document
UN38.3Manufacturer claim · unresolved document setClaimedListed when checked

Printed in the "Certification" row of the eSpire Nano datasheet and product page's General Specifications table, shared by both packs. No certification body, certificate number or scope beyond this list is named, and no issuer record was checked.

Manufacturer document

Official datasheet: Fortress Power eSpire Nano Data Sheet (English) Rev V.ESPIRENANO_042026 · Checked · Earlier document

Certificate guide

Parts and accessories

No sourced accessories or replacement parts listed yet.

Model history

Model identity

Model
FP-Nano-S8-O

Manufacturer SKU unknown · US market

Observed

UL 1973: claimed

Product / system scope unresolved. Listed on the California Energy Commission Battery List (data unchanged since October 1, 2026; downloaded October 11, 2026) as Fortress Power LLC "FP-Nano-S8-I": UL 1973, certifying entity SGS, certificate date 2026-04-07, Ed. 3 : 2022, CEC listing date 2026-05-21. A state equipment list entry, not the certification body's own record.

Issuer record: CEC Battery List, official spreadsheet (data unchanged since October 1, 2026; downloaded October 11, 2026) October 1, 2026 · Checked · Earlier document
Observed

CEC: claimed

Product / system scope unresolved. Model FP-Nano-S8-I listed on the California Energy Commission Battery List (data unchanged since October 1, 2026; downloaded October 11, 2026) under Fortress Power LLC, as "FP-Nano-S8-I"; "FP-Nano-S8-O", CEC listing date 2026-05-21. Matched on the record's model alias "FP-Nano-S8-I". This is an equipment listing, not UL certification or complete-system approval.

Issuer record: CEC Battery List, official spreadsheet (data unchanged since October 1, 2026; downloaded October 11, 2026) October 1, 2026 · Checked · Earlier document
Observed

CEC: claimed

Product / system scope unresolved. Model FP-Nano-S8-O listed on the California Energy Commission Energy Storage System List (data unchanged since October 1, 2026; downloaded October 11, 2026) under Fortress Power LLC (brand Fortress Power), as "FP-Nano-S8-O", CEC listing date 2026-05-11. Matched on the record's model alias "FP-Nano-S8-O". This is an equipment listing, not UL certification or complete-system approval.

Issuer record: CEC Energy Storage System List, official spreadsheet (data unchanged since October 1, 2026; downloaded October 11, 2026) October 1, 2026 · Checked · Earlier document

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