{
  "node": {
    "id": "term:cell-to-pack-ratio",
    "type": "Term",
    "label": "Cell-to-pack ratio",
    "properties": {
      "id": "cell-to-pack-ratio",
      "name": "Cell-to-pack ratio",
      "aka": [
        "gravimetric cell-to-pack ratio",
        "GCTP"
      ],
      "section": "topic-ratings",
      "definition": "The share of a pack’s mass or volume that is cells rather than housing, cooling, busbars and electronics. It is typically 60–75 % by mass; raising it is the point of cell-to-pack and cell-to-chassis designs.",
      "unit": "%",
      "related": [
        "cell-to-pack",
        "specific-energy",
        "pack"
      ],
      "url": "https://lemonergy.com/learn/glossary/cell-to-pack-ratio/",
      "mentions": [
        "cell-to-chassis"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:1029",
      "source": "term:cell-to-pack-ratio",
      "target": "topic:topic-ratings",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:1030",
      "source": "term:cell-to-pack-ratio",
      "target": "term:cell-to-pack",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1031",
      "source": "term:cell-to-pack-ratio",
      "target": "term:specific-energy",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1032",
      "source": "term:cell-to-pack-ratio",
      "target": "term:pack",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/cell-to-pack-ratio/cell-to-chassis",
      "source": "term:cell-to-pack-ratio",
      "target": "term:cell-to-chassis",
      "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-ratings",
      "type": "Topic",
      "label": "Capacity, energy, power and ratings",
      "properties": {
        "id": "topic-ratings",
        "name": "Capacity, energy, power and ratings",
        "lede": "The numbers that size a cell and let two cells be compared.",
        "context": "Separate nameplate ratings from test results.",
        "example": "5 Ah at 3.6 V gives 18 Wh nominally. Integrated measured terminal power may give a different result.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/",
        "lesson_label": "Open capacity and C-rate"
      }
    },
    {
      "id": "term:cell-to-pack",
      "type": "Term",
      "label": "Cell-to-pack",
      "properties": {
        "id": "cell-to-pack",
        "name": "Cell-to-pack",
        "abbr": "CTP",
        "section": "topic-pack",
        "definition": "Building the pack directly from cells without the intermediate module, using large-format cells that bear load themselves. It raises the cell-to-pack ratio and cuts parts, at the cost of making the pack harder to service.",
        "related": [
          "module",
          "cell-to-pack-ratio",
          "cell-to-chassis",
          "blade-cell",
          "ab-battery-system"
        ],
        "url": "https://lemonergy.com/learn/glossary/cell-to-pack/",
        "mentions": []
      }
    },
    {
      "id": "term:specific-energy",
      "type": "Term",
      "label": "Specific energy",
      "properties": {
        "id": "specific-energy",
        "name": "Specific energy",
        "aka": [
          "gravimetric energy density"
        ],
        "section": "topic-ratings",
        "definition": "Stored energy per unit mass, in watt-hours per kilogram. Commercial lithium-ion cells range from about 160 Wh/kg for LFP to around 270 Wh/kg for high-nickel chemistries; at pack level the figure drops by a quarter or more.",
        "unit": "Wh/kg",
        "related": [
          "energy-density",
          "cell-to-pack-ratio",
          "specific-capacity",
          "ragone-plot"
        ],
        "lesson": "fundamentals/capacity-and-c-rate/#energy",
        "url": "https://lemonergy.com/learn/glossary/specific-energy/",
        "mentions": []
      }
    },
    {
      "id": "term:pack",
      "type": "Term",
      "label": "Battery pack",
      "properties": {
        "id": "pack",
        "name": "Battery pack",
        "section": "topic-pack",
        "definition": "The complete battery as installed: modules or cells, the BMS, contactors and fuses, busbars, cooling, sensors and an enclosure. Its energy is the sum of its cells’ energies; its mass and volume are a good deal more.",
        "related": [
          "module",
          "bms",
          "battery-disconnect-unit",
          "thermal-management",
          "cell-to-pack-ratio",
          "enclosure"
        ],
        "lesson": "fundamentals/battery-basics/#cell-module-pack",
        "url": "https://lemonergy.com/learn/glossary/pack/",
        "mentions": []
      }
    },
    {
      "id": "term:cell-to-chassis",
      "type": "Term",
      "label": "Cell-to-chassis",
      "properties": {
        "id": "cell-to-chassis",
        "name": "Cell-to-chassis",
        "abbr": "CTC",
        "aka": [
          "cell-to-body",
          "structural battery"
        ],
        "section": "topic-pack",
        "definition": "Integrating the cells into the vehicle floor itself, so the battery enclosure is the chassis and the cells help carry its loads. It saves mass and height but binds the battery to the car for life.",
        "related": [
          "cell-to-pack",
          "enclosure",
          "cell-to-pack-ratio"
        ],
        "url": "https://lemonergy.com/learn/glossary/cell-to-chassis/",
        "mentions": []
      }
    }
  ]
}