{
  "node": {
    "id": "term:safety-case",
    "type": "Term",
    "label": "Safety case",
    "properties": {
      "id": "safety-case",
      "name": "Safety case",
      "aka": [
        "safety argument"
      ],
      "section": "topic-hvsafety",
      "definition": "A structured argument, backed by evidence, that a system is acceptably safe for its intended use: hazard analysis, safety requirements, design analyses such as FMEA, and test and review results, all traced to one another. ISO 26262 requires one for every item with an ASIL, and a functional safety assessment reviews it before release.",
      "related": [
        "functional-safety",
        "hara",
        "safety-concept",
        "fmea",
        "hardware-safety-metrics"
      ],
      "url": "https://lemonergy.com/learn/glossary/safety-case/",
      "mentions": []
    }
  },
  "edges": [
    {
      "id": "edge:5166",
      "source": "term:safety-case",
      "target": "topic:topic-hvsafety",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:5167",
      "source": "term:safety-case",
      "target": "term:functional-safety",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5168",
      "source": "term:safety-case",
      "target": "term:hara",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5169",
      "source": "term:safety-case",
      "target": "term:safety-concept",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5170",
      "source": "term:safety-case",
      "target": "term:fmea",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5171",
      "source": "term:safety-case",
      "target": "term:hardware-safety-metrics",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5172",
      "source": "term:safety-case",
      "target": "reference:iso-functional",
      "type": "cites",
      "properties": {
        "sourceFile": "wiki-references.json",
        "scope": "direct technical reference"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-hvsafety",
      "type": "Topic",
      "label": "High-voltage and functional safety",
      "properties": {
        "id": "topic-hvsafety",
        "name": "High-voltage and functional safety",
        "lede": "Keeping people safe from the pack’s voltage and keeping its electronics safe when they fail: insulation, switching, fusing and the functional-safety process.",
        "context": "Relate protection to faults, detection and response.",
        "example": "Normal-operation current limits do not demonstrate correct contactor behavior under a welded-contact or sensor fault.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-basics/",
        "lesson_label": "Open battery basics"
      }
    },
    {
      "id": "term:functional-safety",
      "type": "Term",
      "label": "Functional safety",
      "properties": {
        "id": "functional-safety",
        "name": "Functional safety",
        "abbr": "ISO 26262",
        "aka": [
          "ASIL"
        ],
        "section": "topic-hvsafety",
        "definition": "The discipline, standardised for vehicles in ISO 26262, of making sure electronic failures do not cause harm. Battery functions such as overvoltage protection are classified by risk into ASIL levels A to D, which set how redundant and verified their hardware and software must be.",
        "related": [
          "bms",
          "high-voltage-interlock",
          "insulation-resistance",
          "fmea",
          "mcu",
          "iso-13849"
        ],
        "url": "https://lemonergy.com/learn/glossary/functional-safety/",
        "mentions": []
      }
    },
    {
      "id": "term:hara",
      "type": "Term",
      "label": "Hazard analysis and risk assessment",
      "properties": {
        "id": "hara",
        "name": "Hazard analysis and risk assessment",
        "abbr": "HARA",
        "section": "topic-hvsafety",
        "definition": "The ISO 26262 step that lists the hazards a function could cause, rates each in its driving situation for severity (S0–S3), exposure (E0–E4) and controllability (C0–C3), and combines them into an ASIL or QM. Each hazard becomes a safety goal, such as ‘prevent cell overcharge leading to thermal runaway’, that the design must meet.",
        "related": [
          "functional-safety",
          "safety-concept",
          "fmea",
          "safety-case",
          "thermal-runaway"
        ],
        "url": "https://lemonergy.com/learn/glossary/hara/",
        "mentions": [
          "overcharge"
        ]
      }
    },
    {
      "id": "term:safety-concept",
      "type": "Term",
      "label": "Functional and technical safety concepts",
      "properties": {
        "id": "safety-concept",
        "name": "Functional and technical safety concepts",
        "abbr": "FSC, TSC",
        "aka": [
          "functional safety concept",
          "technical safety concept"
        ],
        "section": "topic-hvsafety",
        "definition": "The two layers that turn safety goals into a design under ISO 26262. The functional safety concept states what must happen — detect a cell above its voltage limit and open the contactors within a set time — without naming parts; the technical safety concept allocates those requirements to hardware and software, such as a specific monitoring chip, diagnostic and contactor driver.",
        "related": [
          "hara",
          "functional-safety",
          "hardware-safety-metrics",
          "safety-case",
          "redundant-bms"
        ],
        "url": "https://lemonergy.com/learn/glossary/safety-concept/",
        "mentions": [
          "contactor"
        ]
      }
    },
    {
      "id": "term:fmea",
      "type": "Term",
      "label": "Failure mode and effects analysis",
      "properties": {
        "id": "fmea",
        "name": "Failure mode and effects analysis",
        "abbr": "FMEA",
        "section": "topic-hvsafety",
        "definition": "A structured review that lists every way a component or process could fail, its effect, and how likely it is to happen and be detected, scoring each to prioritise fixes. Battery programmes run it on the cell, the pack design and the production process.",
        "related": [
          "functional-safety",
          "abuse-testing",
          "cell-design",
          "fault-tree-analysis"
        ],
        "url": "https://lemonergy.com/learn/glossary/fmea/",
        "mentions": []
      }
    },
    {
      "id": "term:hardware-safety-metrics",
      "type": "Term",
      "label": "Hardware safety metrics",
      "properties": {
        "id": "hardware-safety-metrics",
        "name": "Hardware safety metrics",
        "abbr": "SPFM, LFM, PMHF",
        "aka": [
          "single-point fault metric",
          "latent fault metric",
          "probabilistic metric for random hardware failures",
          "hardware architectural metrics"
        ],
        "section": "topic-hvsafety",
        "definition": "The ISO 26262 numbers showing that random hardware failures are under control. The single-point and latent fault metrics are the shares of failures that safety mechanisms cover — at least 99% and 90% for ASIL D — and PMHF is the residual rate of violating a safety goal, below 10⁻⁸ per hour (10 FIT) for ASIL D.",
        "related": [
          "functional-safety",
          "diagnostic-coverage",
          "safety-concept",
          "fmea",
          "redundant-bms"
        ],
        "url": "https://lemonergy.com/learn/glossary/hardware-safety-metrics/",
        "mentions": []
      }
    },
    {
      "id": "reference:iso-functional",
      "type": "Reference",
      "label": "ISO 26262-1:2018 — Road vehicles — Functional safety — Part 1: Vocabulary",
      "properties": {
        "title": "ISO 26262-1:2018 — Road vehicles — Functional safety — Part 1: Vocabulary",
        "publisher": "International Organization for Standardization",
        "url": "https://www.iso.org/standard/68383.html",
        "type": "Standard catalogue",
        "scope": "Scope and terminology of automotive electrical/electronic functional safety. The catalogue is not the full standard.",
        "year": 2018,
        "accessed": "2026-10-27"
      }
    }
  ]
}