Public evidence

electrical.battery.pack_sizing

Machine-checked verification for calculation version 1.2.0 · tier internally_reviewed

Open calculator API Capability Download JSON CVP Manifest MCP Review policy

CVP status

Planning estimate — not BMS / chemistry pack design

Declared partition coverage: PASS · 4/4 declared partitions (watts, amps, cells, invalid-domain)
Versions: Calculation 1.2.0 · CVP protocol 1.0.0-proposed · Evidence 2026-10-28.meta-metrics-v2
Verification revision: 2026-10-28.meta-metrics-v2 · 7/7 property · digest b8e9dd974946

Verification

Legacy regression suite: 27/27 calculation tests · Production surface contract 6/6

Three distinct suites: educational examples on the calculator page, this legacy regression count (27/27 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.2.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Verification revision 2026-10-28.meta-metrics-v2. Calculation version 1.2.0. CVP 1.0.0-proposed. 3/3 golden · 16/16 CVP boundary · 14/14 invalid · 7/7 property · 2/2 metamorphic · 2/2 round-trip · 3/3 cross-interface · 2/2 cross-calculator · 6/6 CVP contract. digest b8e9dd974946.

Golden (oracle-backed) 3 / 3
CVP boundary 16 / 16
Invalid input 14 / 14
Property 7 / 7
Metamorphic 2 / 2
Round-trip 2 / 2
Cross-interface 3 / 3
Cross-calculator 2 / 2
CVP contract 6 / 6
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session.
Assurance Engineering

release artifacts aligned PASS
schema output required declared PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS
rest success payload validates schema PASS

Fingerprint sha256:b3a87a18a21fe41a5c7d2da0d313bf40be7ccbbf30980df5749b8ea96dbd34ca

Input schema sha256:efbfe6f1c002ef9ba44af12ce224324e0618ece83cfc78c98f4db8b38c5f70f3 · Output schema sha256:acb2f259f709c99aca6f4aac55846212b216b63f875beae2644fd0d8aecde756 · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: battery-pack-sizing
Engine: battery-pack-sizing
Engine build: 2026-09-10
Evidence core: 2026-09-05T15:29:50.831Z
Rendered: 2026-11-10T05:18:41.736Z
Last reviewed: 2026-09-05

Assumptions

Constant load; ceil cell counts as nominal packing estimate; not Peukert or BMS design
Amps mode I_A is battery-side; η does not enter Ah
V is target/system nominal voltage; V_pack = Ns·V_cell may differ

Limitations

Constant-load inverse of BatteryRuntimeBaseInput / battery_runtime 1.2+
Amps mode = battery-side current; η does not enter Ah
Cell Ns/Np use ceil — nominal packing estimate only, not BMS / chemistry pack design
When V_pack ≠ V_target the result includes warning PACK_VOLTAGE_DIFFERS_FROM_TARGET
mode=watts requires P_W; mode=amps requires I_A
V_cell XOR incomplete pair → NEEDS_TWO_INPUTS (both or neither)

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

IEC 60050 — International Electrotechnical Vocabulary — Electric battery capacity and related quantities
Supports: Ah capacity and Wh energy relationship E ≈ Q·V for nominal estimates
Victron Energy — Battery capacity and Peukert exponent — SmartShunt / battery monitor documentation
Supports: Ideal Ah ≈ I·t under constant current; Peukert and rate effects as reasons this tool stays first-order (Not Peukert)
CalculatorX Battery Runtime capability — Constant-load watts/amps model (1.2+) — internal method dependency
Supports: Inverse capacity sizing; shared watts/amps semantics with electrical.battery_runtime

Methods

Algorithms this engine uses. Not external references.

derived_from:electrical.battery_runtime@1.2.0 — inverse constant-load watts/amps model

Verification disclosure

Aggregate outcomes, scope and artifact commitments are public. Complete test inputs, expected values, execution records and oracle infrastructure are retained privately. This summary does not independently reproduce the full verification run.