{
  "node": {
    "id": "term:dead-lithium",
    "type": "Term",
    "label": "Dead lithium",
    "properties": {
      "id": "dead-lithium",
      "name": "Dead lithium",
      "aka": [
        "inactive lithium"
      ],
      "section": "topic-aging",
      "definition": "Plated lithium metal that has lost electrical contact with the electrode, usually because SEI formed around it. It can no longer take part in cycling, so every gram of it is permanent capacity loss.",
      "related": [
        "lithium-plating",
        "loss-of-lithium-inventory",
        "sei",
        "titration-gas-chromatography"
      ],
      "url": "https://lemonergy.com/learn/glossary/dead-lithium/",
      "mentions": [
        "electrode"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:1444",
      "source": "term:dead-lithium",
      "target": "topic:topic-aging",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:1445",
      "source": "term:dead-lithium",
      "target": "term:lithium-plating",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1446",
      "source": "term:dead-lithium",
      "target": "term:loss-of-lithium-inventory",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1447",
      "source": "term:dead-lithium",
      "target": "term:sei",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1448",
      "source": "term:dead-lithium",
      "target": "term:titration-gas-chromatography",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/dead-lithium/electrode",
      "source": "term:dead-lithium",
      "target": "term:electrode",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:1450",
      "source": "term:dead-lithium",
      "target": "reference:edge-degradation",
      "type": "cites",
      "properties": {
        "sourceFile": "wiki-references.json",
        "scope": "direct technical reference"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-aging",
      "type": "Topic",
      "label": "Aging and degradation",
      "properties": {
        "id": "topic-aging",
        "name": "Aging and degradation",
        "lede": "Why a cell loses capacity and gains resistance, and the mechanisms behind it.",
        "context": "Separate mechanisms, observations and fitted models.",
        "example": "Capacity loss and resistance rise can have different causes; a film-growth curve cannot identify both.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-aging/",
        "lesson_label": "Open aging"
      }
    },
    {
      "id": "term:lithium-plating",
      "type": "Term",
      "label": "Lithium plating",
      "properties": {
        "id": "lithium-plating",
        "name": "Lithium plating",
        "section": "topic-aging",
        "definition": "Lithium metal depositing on the negative-electrode surface instead of intercalating into it. It is promoted by charging at low temperature or high current.",
        "related": [
          "dendrite",
          "fast-charging",
          "intercalation",
          "np-ratio",
          "dead-lithium",
          "electrodeposition"
        ],
        "lesson": "fundamentals/battery-aging/#plating",
        "url": "https://lemonergy.com/learn/glossary/lithium-plating/",
        "mentions": []
      }
    },
    {
      "id": "term:loss-of-lithium-inventory",
      "type": "Term",
      "label": "Loss of lithium inventory",
      "properties": {
        "id": "loss-of-lithium-inventory",
        "name": "Loss of lithium inventory",
        "abbr": "LLI",
        "section": "topic-aging",
        "definition": "The degradation mode in which cyclable lithium is consumed by side reactions — SEI growth, plating, electrolyte decomposition — and can no longer shuttle between the electrodes. It is the dominant cause of capacity fade in most lithium-ion cells.",
        "related": [
          "sei",
          "lithium-plating",
          "capacity-fade",
          "loss-of-active-material",
          "coulombic-efficiency"
        ],
        "url": "https://lemonergy.com/learn/glossary/loss-of-lithium-inventory/",
        "mentions": [
          "electrolyte",
          "aging-mechanism",
          "electrolyte-decomposition"
        ]
      }
    },
    {
      "id": "term:sei",
      "type": "Term",
      "label": "Solid–electrolyte interphase",
      "properties": {
        "id": "sei",
        "name": "Solid–electrolyte interphase",
        "abbr": "SEI",
        "section": "topic-aging",
        "definition": "A film of electrolyte reaction products on the negative-electrode particles — graphite, and also silicon or lithium metal. It protects the electrode from further reaction but grows slowly for the whole life of the cell, consuming cyclable lithium.",
        "related": [
          "passivation",
          "formation",
          "calendar-aging",
          "loss-of-lithium-inventory",
          "cei"
        ],
        "lesson": "fundamentals/battery-aging/#sei",
        "url": "https://lemonergy.com/learn/glossary/sei/",
        "mentions": [
          "electrode",
          "graphite",
          "electrolyte"
        ]
      }
    },
    {
      "id": "term:titration-gas-chromatography",
      "type": "Term",
      "label": "Titration gas chromatography",
      "properties": {
        "id": "titration-gas-chromatography",
        "name": "Titration gas chromatography",
        "abbr": "TGC",
        "aka": [
          "water titration",
          "inactive lithium quantification"
        ],
        "section": "topic-analysis",
        "definition": "Quantifying metallic lithium in a cycled electrode by reacting it with water and measuring the hydrogen released by gas chromatography. Most SEI lithium compounds give off no hydrogen, so the method separates dead metallic lithium from SEI lithium down to about a microgram; it showed that unreacted metal dominates capacity loss in lithium-metal cells.",
        "formula": "2Li + 2H₂O → 2LiOH + H₂",
        "related": [
          "dead-lithium",
          "lithium-plating",
          "lithium-metal-battery",
          "loss-of-lithium-inventory",
          "gas-chromatography-mass-spectrometry"
        ],
        "example": {
          "title": "Use the reaction stoichiometry",
          "text": "In the ideal reaction 2Li + 2H₂O → 2LiOH + H₂, 1 μmol of measured H₂ corresponds to 2 μmol of metallic Li. Interfering gas-producing species and instrument calibration must be assessed."
        },
        "notes": [
          "This is a stoichiometric interpretation, not instructions for opening or reacting a battery."
        ],
        "url": "https://lemonergy.com/learn/glossary/titration-gas-chromatography/",
        "mentions": [
          "electrode",
          "sei"
        ]
      }
    },
    {
      "id": "term:electrode",
      "type": "Term",
      "label": "Electrode",
      "properties": {
        "id": "electrode",
        "name": "Electrode",
        "section": "topic-components",
        "definition": "A solid conductor where the cell’s reaction happens, in contact with the electrolyte. A lithium-ion cell has a negative electrode and a positive electrode, each a porous coating on a metal foil.",
        "related": [
          "negative-electrode",
          "positive-electrode",
          "porous-electrode",
          "current-collector"
        ],
        "lesson": "fundamentals/cell-anatomy/#components",
        "example": {
          "title": "Two transport paths",
          "text": "Electrons need connected solid paths to the collector; ions need electrolyte paths to reaction sites. More of one constituent displaces others at fixed volume."
        },
        "url": "https://lemonergy.com/learn/glossary/electrode/",
        "mentions": [
          "electrolyte",
          "coating"
        ]
      }
    },
    {
      "id": "reference:edge-degradation",
      "type": "Reference",
      "label": "Lithium ion battery degradation: what you need to know",
      "properties": {
        "title": "Lithium ion battery degradation: what you need to know",
        "publisher": "Physical Chemistry Chemical Physics",
        "url": "https://doi.org/10.1039/D1CP00359C",
        "type": "Review article",
        "scope": "Degradation mechanisms, modes, operational effects and their interactions.",
        "year": 2021,
        "accessed": "2026-10-27"
      }
    }
  ]
}