{
  "node": {
    "id": "term:metal-particle-contamination",
    "type": "Term",
    "label": "Metal particle contamination",
    "properties": {
      "id": "metal-particle-contamination",
      "name": "Metal particle contamination",
      "aka": [
        "metal particle",
        "metallic contamination",
        "foreign particles"
      ],
      "section": "topic-manufacturing",
      "definition": "Stray fragments of iron, copper, zinc or steel from raw materials, worn equipment or cutting. A particle tens of micrometres across can pierce the separator, or dissolve and regrow across it, causing high self-discharge or a latent internal short circuit — the cause of the 2006 laptop battery recalls. Magnetic filters, cleanroom discipline and K-value screening keep them out.",
      "related": [
        "internal-short-circuit",
        "cleanroom",
        "k-value",
        "self-discharge",
        "burr"
      ],
      "url": "https://lemonergy.com/learn/glossary/metal-particle-contamination/",
      "mentions": [
        "separator",
        "short-circuit"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:4847",
      "source": "term:metal-particle-contamination",
      "target": "topic:topic-manufacturing",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:4848",
      "source": "term:metal-particle-contamination",
      "target": "term:internal-short-circuit",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4849",
      "source": "term:metal-particle-contamination",
      "target": "term:cleanroom",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4850",
      "source": "term:metal-particle-contamination",
      "target": "term:k-value",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4851",
      "source": "term:metal-particle-contamination",
      "target": "term:self-discharge",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4852",
      "source": "term:metal-particle-contamination",
      "target": "term:burr",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/metal-particle-contamination/separator",
      "source": "term:metal-particle-contamination",
      "target": "term:separator",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/metal-particle-contamination/short-circuit",
      "source": "term:metal-particle-contamination",
      "target": "term:short-circuit",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-manufacturing",
      "type": "Topic",
      "label": "Manufacturing",
      "properties": {
        "id": "topic-manufacturing",
        "name": "Manufacturing",
        "lede": "The steps that turn powders and foils into a finished cell, in production order.",
        "context": "Place operations and quality checks in process order.",
        "example": "An electrode can meet coating mass targets but fail adhesion or moisture checks later.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/cell-production/",
        "lesson_label": "Open production"
      }
    },
    {
      "id": "term:internal-short-circuit",
      "type": "Term",
      "label": "Internal short circuit",
      "properties": {
        "id": "internal-short-circuit",
        "name": "Internal short circuit",
        "abbr": "ISC",
        "section": "topic-safety",
        "definition": "An unintended electronic path between the electrodes inside a cell — through a metal particle, a burr, a damaged separator or lithium deposits. It discharges the cell internally and turns its energy into local heat.",
        "related": [
          "thermal-runaway",
          "dendrite",
          "separator",
          "external-short-circuit",
          "self-discharge",
          "internal-short-trigger-device"
        ],
        "lesson": "fundamentals/cell-anatomy/#short-circuit",
        "url": "https://lemonergy.com/learn/glossary/internal-short-circuit/",
        "mentions": [
          "electronic-path",
          "burr",
          "metal-particle-contamination"
        ]
      }
    },
    {
      "id": "term:cleanroom",
      "type": "Term",
      "label": "Cleanroom",
      "properties": {
        "id": "cleanroom",
        "name": "Cleanroom",
        "aka": [
          "clean room",
          "ISO 14644"
        ],
        "section": "topic-manufacturing",
        "definition": "A room whose airborne particle count is held to a class by filtered air, overpressure and gowning, graded under ISO 14644-1: ISO class 7 allows at most 352,000 particles of 0.5 µm or larger per cubic metre. It controls particles, whereas a dry room controls moisture; cell assembly usually needs both, because one metal particle can short a cell.",
        "related": [
          "dry-room",
          "metal-particle-contamination",
          "cell-assembly",
          "internal-short-circuit"
        ],
        "url": "https://lemonergy.com/learn/glossary/cleanroom/",
        "mentions": []
      }
    },
    {
      "id": "term:k-value",
      "type": "Term",
      "label": "K-value",
      "properties": {
        "id": "k-value",
        "name": "K-value",
        "aka": [
          "OCV drop rate"
        ],
        "section": "topic-manufacturing",
        "definition": "The rate at which a cell’s open-circuit voltage falls during the production aging step, in millivolts per day. A high K-value signals an internal short or contamination, and such cells are scrapped before shipment.",
        "unit": "mV/day",
        "related": [
          "aging-step",
          "self-discharge",
          "open-circuit-voltage",
          "internal-short-circuit"
        ],
        "url": "https://lemonergy.com/learn/glossary/k-value/",
        "mentions": []
      }
    },
    {
      "id": "term:self-discharge",
      "type": "Term",
      "label": "Self-discharge",
      "properties": {
        "id": "self-discharge",
        "name": "Self-discharge",
        "section": "topic-charging",
        "definition": "The slow loss of stored charge while a cell is not in use. An unexpected rise can signal a leakage path or a soft internal short.",
        "unit": "%/month",
        "related": [
          "internal-short-circuit",
          "calendar-aging",
          "k-value",
          "calendar-life",
          "self-discharge-test"
        ],
        "lesson": "fundamentals/battery-aging/#check-yourself",
        "url": "https://lemonergy.com/learn/glossary/self-discharge/",
        "mentions": []
      }
    },
    {
      "id": "term:burr",
      "type": "Term",
      "label": "Burr",
      "properties": {
        "id": "burr",
        "name": "Burr",
        "aka": [
          "burrs",
          "edge burr",
          "slitting burr",
          "slitter burr"
        ],
        "section": "topic-manufacturing",
        "definition": "A sharp raised lip of foil, or a loose flake of coating, left at a cut electrode edge by slitting or notching. The separator is only about 10–25 µm thick, so a burr of similar height can pierce it under stack pressure and cause an internal short circuit; edges are therefore inspected and worn knives replaced before burrs grow.",
        "related": [
          "slitting",
          "notching",
          "internal-short-circuit",
          "separator",
          "laser-cutting"
        ],
        "url": "https://lemonergy.com/learn/glossary/burr/",
        "mentions": [
          "electrode",
          "coating",
          "stack-pressure",
          "short-circuit"
        ]
      }
    },
    {
      "id": "term:separator",
      "type": "Term",
      "label": "Separator",
      "properties": {
        "id": "separator",
        "name": "Separator",
        "section": "topic-electrolytes",
        "definition": "A porous, electronically insulating film between the electrodes. Electrons cannot cross it; ions move through the electrolyte in its pores.",
        "related": [
          "electrolyte",
          "ceramic-coated-separator",
          "separator-shutdown",
          "internal-short-circuit",
          "porosity"
        ],
        "lesson": "fundamentals/cell-architecture/#separator",
        "example": {
          "title": "Different conduction paths",
          "text": "A separator prevents direct electronic contact while permitting ionic transport through its electrolyte-filled structure."
        },
        "url": "https://lemonergy.com/learn/glossary/separator/",
        "mentions": []
      }
    },
    {
      "id": "term:short-circuit",
      "type": "Term",
      "label": "Short circuit",
      "properties": {
        "id": "short-circuit",
        "name": "Short circuit",
        "section": "topic-units",
        "definition": "A connection of negligible resistance between two points that should be separated, so current is limited only by the source. For a battery it may be external, across the terminals, or internal, between the electrodes inside the cell.",
        "related": [
          "external-short-circuit",
          "internal-short-circuit",
          "fuse",
          "ohms-law"
        ],
        "lesson": "fundamentals/cell-anatomy/#short-circuit",
        "url": "https://lemonergy.com/learn/glossary/short-circuit/",
        "mentions": []
      }
    }
  ]
}