{
  "node": {
    "id": "term:pressure-equalisation-vent",
    "type": "Term",
    "label": "Pressure-equalisation vent",
    "properties": {
      "id": "pressure-equalisation-vent",
      "name": "Pressure-equalisation vent",
      "aka": [
        "breather membrane",
        "pack breather",
        "pressure equalization vent",
        "pressure compensation element",
        "ePTFE vent"
      ],
      "section": "topic-pack",
      "definition": "A small vent in a sealed pack enclosure, closed by a microporous membrane, often expanded PTFE, that passes air but not water or dust. It equalises internal pressure as temperature and altitude change, protecting the seals without losing the IP rating; some designs add a burst element that opens wide to release gas in thermal runaway.",
      "related": [
        "enclosure",
        "ip-rating",
        "vent",
        "venting",
        "thermal-runaway"
      ],
      "url": "https://lemonergy.com/learn/glossary/pressure-equalisation-vent/",
      "mentions": [
        "ptfe"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:5017",
      "source": "term:pressure-equalisation-vent",
      "target": "topic:topic-pack",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:5018",
      "source": "term:pressure-equalisation-vent",
      "target": "term:enclosure",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5019",
      "source": "term:pressure-equalisation-vent",
      "target": "term:ip-rating",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5020",
      "source": "term:pressure-equalisation-vent",
      "target": "term:vent",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5021",
      "source": "term:pressure-equalisation-vent",
      "target": "term:venting",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:5022",
      "source": "term:pressure-equalisation-vent",
      "target": "term:thermal-runaway",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/pressure-equalisation-vent/ptfe",
      "source": "term:pressure-equalisation-vent",
      "target": "term:ptfe",
      "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-pack",
      "type": "Topic",
      "label": "Modules, packs and battery management",
      "properties": {
        "id": "topic-pack",
        "name": "Modules, packs and battery management",
        "lede": "From a single cell to a working battery system, and the electronics that keep it safe.",
        "context": "Make series/parallel architecture explicit.",
        "example": "Twelve 3.6 V, 5 Ah cells in 6s2p give 21.6 V, 10 Ah and 216 Wh nominally before other restrictions.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/cell-architecture/",
        "lesson_label": "Open cell architecture"
      }
    },
    {
      "id": "term:enclosure",
      "type": "Term",
      "label": "Enclosure",
      "properties": {
        "id": "enclosure",
        "name": "Enclosure",
        "aka": [
          "battery housing",
          "battery tray"
        ],
        "section": "topic-pack",
        "definition": "The sealed case that carries the modules, protects them in a crash, keeps water out to an IP67 rating or better and vents gas in a thermal event. In many cars it is a structural part of the body.",
        "related": [
          "pack",
          "ip-rating",
          "cell-to-chassis",
          "venting",
          "gigacasting",
          "ul-94"
        ],
        "url": "https://lemonergy.com/learn/glossary/enclosure/",
        "mentions": []
      }
    },
    {
      "id": "term:ip-rating",
      "type": "Term",
      "label": "IP rating",
      "properties": {
        "id": "ip-rating",
        "name": "IP rating",
        "aka": [
          "ingress protection"
        ],
        "section": "topic-pack",
        "definition": "A two-digit code for how well an enclosure keeps out solids and water: the first digit for dust, the second for water. Battery packs are typically IP67, dust-tight and able to survive brief immersion.",
        "related": [
          "enclosure",
          "pack",
          "immersion-test"
        ],
        "url": "https://lemonergy.com/learn/glossary/ip-rating/",
        "mentions": []
      }
    },
    {
      "id": "term:vent",
      "type": "Term",
      "label": "Vent",
      "properties": {
        "id": "vent",
        "name": "Vent",
        "aka": [
          "burst disc",
          "rupture disc"
        ],
        "section": "topic-safety",
        "definition": "A scored area or a membrane in the cell can that opens at a set pressure, around ten to thirty bar for a cylindrical cell, so that gas escapes in a chosen direction instead of the case splitting at random.",
        "related": [
          "venting",
          "can",
          "current-interrupt-device"
        ],
        "url": "https://lemonergy.com/learn/glossary/vent/",
        "mentions": [
          "cylindrical-cell"
        ]
      }
    },
    {
      "id": "term:venting",
      "type": "Term",
      "label": "Venting",
      "properties": {
        "id": "venting",
        "name": "Venting",
        "section": "topic-safety",
        "definition": "The controlled release of gas and vapour from a cell whose internal pressure has risen too far, through a vent designed to open before the case bursts. The vented gas is flammable and toxic, so packs route it away from occupants.",
        "related": [
          "vent",
          "gas-generation",
          "thermal-runaway",
          "off-gas"
        ],
        "url": "https://lemonergy.com/learn/glossary/venting/",
        "mentions": []
      }
    },
    {
      "id": "term:thermal-runaway",
      "type": "Term",
      "label": "Thermal runaway",
      "properties": {
        "id": "thermal-runaway",
        "name": "Thermal runaway",
        "section": "topic-safety",
        "definition": "Self-accelerating heating in a cell: heat speeds up reactions that release more heat, until the cell vents, catches fire or ruptures. An internal short, overcharge or external heating can trigger it.",
        "related": [
          "onset-temperature",
          "thermal-propagation",
          "venting",
          "separator-shutdown",
          "thermal-runaway-energy",
          "exothermic"
        ],
        "lesson": "fundamentals/cell-anatomy/#short-circuit",
        "url": "https://lemonergy.com/learn/glossary/thermal-runaway/",
        "mentions": [
          "overcharge"
        ]
      }
    },
    {
      "id": "term:ptfe",
      "type": "Term",
      "label": "PTFE",
      "properties": {
        "id": "ptfe",
        "name": "PTFE",
        "aka": [
          "polytetrafluoroethylene",
          "Teflon"
        ],
        "section": "topic-components",
        "definition": "The fluoropolymer binder of dry electrode processes: under shear its particles draw out into fine fibrils that web the active material together without any solvent. It is unstable at the low potential of graphite, which complicates dry negative electrodes.",
        "related": [
          "dry-electrode",
          "binder",
          "pvdf"
        ],
        "url": "https://lemonergy.com/learn/glossary/ptfe/",
        "mentions": [
          "electrode",
          "active-material",
          "graphite"
        ]
      }
    }
  ]
}