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  "generated_at": "2026-11-10T05:18:41.736Z",
  "engine_build": "2026-09-10",
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  "reviewer_role": "electrical-engineer",
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  "page": "https://www.calculatorx.com/calc/electric/battery-pack-sizing",
  "api": "https://www.calculatorx.com/api/v1/calc/battery-pack-sizing",
  "schema_input": "https://www.calculatorx.com/schemas/electrical.battery.pack_sizing.input.json",
  "schema_output": "https://www.calculatorx.com/schemas/electrical.battery.pack_sizing.output.json",
  "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)"
  ],
  "boundary_conditions": [
    "Only one of V_cell/capacity_cell_Ah → NEEDS_TWO_INPUTS",
    "Bad mode → INVALID_MODE; dod/eta out of range → FRACTION_OUT_OF_RANGE",
    "t/V/P/I ≤ 0 → VALUE_MUST_BE_POSITIVE / VOLTAGE_MUST_BE_POSITIVE / LOAD_MUST_BE_POSITIVE",
    "V_pack ≠ V → warning PACK_VOLTAGE_DIFFERS_FROM_TARGET"
  ],
  "sources": [
    {
      "title": "IEC 60050 — International Electrotechnical Vocabulary",
      "section": "Electric battery capacity and related quantities",
      "supports": "Ah capacity and Wh energy relationship E ≈ Q·V for nominal estimates",
      "kind": "standard"
    },
    {
      "title": "Victron Energy — Battery capacity and Peukert exponent",
      "section": "SmartShunt / battery monitor documentation",
      "url": "https://www.victronenergy.com/media/pg/SmartShunt/en/battery-capacity-and-peukert-exponent.html",
      "supports": "Ideal Ah ≈ I·t under constant current; Peukert and rate effects as reasons this tool stays first-order (Not Peukert)",
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      "title": "CalculatorX Battery Runtime capability",
      "section": "Constant-load watts/amps model (1.2+) — internal method dependency",
      "supports": "Inverse capacity sizing; shared watts/amps semantics with electrical.battery_runtime",
      "kind": "other"
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