{
  "node": {
    "id": "term:current-collector-corrosion",
    "type": "Term",
    "label": "Current-collector corrosion",
    "properties": {
      "id": "current-collector-corrosion",
      "name": "Current-collector corrosion",
      "section": "topic-aging",
      "definition": "Attack on the foils: aluminium pitting at high potential when the passive film fails, or copper dissolving if the negative electrode is driven above about 3.5 V vs Li/Li⁺ by over-discharge. Both raise resistance and can shed metal into the cell.",
      "related": [
        "copper-dissolution",
        "aluminium-foil",
        "over-discharge",
        "impedance-rise"
      ],
      "lesson": "fundamentals/battery-aging/#corrosion",
      "url": "https://lemonergy.com/learn/glossary/current-collector-corrosion/",
      "mentions": [
        "electrode",
        "negative-electrode"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:1533",
      "source": "term:current-collector-corrosion",
      "target": "topic:topic-aging",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:1534",
      "source": "term:current-collector-corrosion",
      "target": "term:copper-dissolution",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1535",
      "source": "term:current-collector-corrosion",
      "target": "term:aluminium-foil",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1536",
      "source": "term:current-collector-corrosion",
      "target": "term:over-discharge",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:1537",
      "source": "term:current-collector-corrosion",
      "target": "term:impedance-rise",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/current-collector-corrosion/electrode",
      "source": "term:current-collector-corrosion",
      "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:mentions/current-collector-corrosion/negative-electrode",
      "source": "term:current-collector-corrosion",
      "target": "term:negative-electrode",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:1540",
      "source": "term:current-collector-corrosion",
      "target": "lesson:fundamentals/battery-aging/",
      "type": "explainedIn",
      "properties": {
        "sourceFile": "terms.json",
        "url": "https://lemonergy.com/learn/fundamentals/battery-aging/#corrosion"
      }
    }
  ],
  "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:copper-dissolution",
      "type": "Term",
      "label": "Copper dissolution",
      "properties": {
        "id": "copper-dissolution",
        "name": "Copper dissolution",
        "section": "topic-aging",
        "definition": "Oxidation of the copper current collector when a cell is over-discharged and the negative electrode’s potential rises too high. Dissolved copper redeposits on recharge as metallic filaments that can short the separator, which is why over-discharged cells are not simply recharged.",
        "related": [
          "over-discharge",
          "copper-foil",
          "internal-short-circuit",
          "current-collector-corrosion"
        ],
        "url": "https://lemonergy.com/learn/glossary/copper-dissolution/",
        "mentions": [
          "electrode",
          "negative-electrode",
          "current-collector",
          "separator",
          "oxidation"
        ]
      }
    },
    {
      "id": "term:aluminium-foil",
      "type": "Term",
      "label": "Aluminium foil",
      "properties": {
        "id": "aluminium-foil",
        "name": "Aluminium foil",
        "section": "topic-components",
        "definition": "The positive current collector, typically 10–15 µm thick. A thin passive film keeps it stable at the high potential of the positive electrode, where copper would corrode.",
        "related": [
          "current-collector",
          "copper-foil",
          "passivation"
        ],
        "example": {
          "title": "Keep normalization consistent",
          "text": "Active-material capacity can remain unchanged while a heavier foil lowers a finished electrode’s capacity per unit total mass."
        },
        "url": "https://lemonergy.com/learn/glossary/aluminium-foil/",
        "mentions": [
          "electrode",
          "positive-electrode"
        ]
      }
    },
    {
      "id": "term:over-discharge",
      "type": "Term",
      "label": "Over-discharge",
      "properties": {
        "id": "over-discharge",
        "name": "Over-discharge",
        "aka": [
          "deep discharge"
        ],
        "section": "topic-charging",
        "definition": "Discharging below the lower cutoff voltage. Near 1.5 V the copper current collector begins to dissolve, and on the next charge it can redeposit as metal that shorts the cell, so a deeply discharged cell should not simply be recharged.",
        "related": [
          "cutoff-voltage",
          "copper-dissolution",
          "internal-short-circuit",
          "bms",
          "low-voltage-disconnect"
        ],
        "url": "https://lemonergy.com/learn/glossary/over-discharge/",
        "mentions": [
          "current-collector"
        ]
      }
    },
    {
      "id": "term:impedance-rise",
      "type": "Term",
      "label": "Impedance rise",
      "properties": {
        "id": "impedance-rise",
        "name": "Impedance rise",
        "aka": [
          "resistance growth",
          "power fade"
        ],
        "section": "topic-aging",
        "definition": "An increase in a cell’s internal resistance as it ages. It costs voltage under load and therefore power, even while the stored charge is still there.",
        "related": [
          "internal-resistance",
          "sei",
          "cei",
          "state-of-power",
          "state-of-health"
        ],
        "lesson": "fundamentals/battery-aging/#crystals",
        "url": "https://lemonergy.com/learn/glossary/impedance-rise/",
        "mentions": [
          "closed-circuit-voltage"
        ]
      }
    },
    {
      "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": "term:negative-electrode",
      "type": "Term",
      "label": "Negative electrode",
      "properties": {
        "id": "negative-electrode",
        "name": "Negative electrode",
        "section": "topic-components",
        "definition": "The electrode at the lower potential, usually graphite on copper foil in a lithium-ion cell. It holds the lithium when the cell is charged and releases it on discharge, and industry calls it the anode.",
        "related": [
          "anode",
          "graphite",
          "positive-electrode",
          "copper-foil"
        ],
        "lesson": "fundamentals/cell-anatomy/#anode-cathode",
        "example": {
          "title": "Keep the polarity name",
          "text": "Graphite remains the negative electrode during charge and discharge, while the anode/cathode reaction labels change with operating direction."
        },
        "url": "https://lemonergy.com/learn/glossary/negative-electrode/",
        "mentions": [
          "electrode"
        ]
      }
    },
    {
      "id": "lesson:fundamentals/battery-aging/",
      "type": "Lesson",
      "label": "Lesson 4 · Battery aging",
      "properties": {
        "url": "https://lemonergy.com/learn/fundamentals/battery-aging/"
      }
    }
  ]
}