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  "node": {
    "id": "term:vc",
    "type": "Term",
    "label": "Vinylene carbonate",
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      "name": "Vinylene carbonate",
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      "section": "topic-electrolytes",
      "definition": "The most common SEI-forming additive, used at 1–3 %. It is reduced before the solvent on the first charge and polymerises into a thinner, more flexible SEI that lengthens cycle life.",
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      "label": "Electrolytes and separators",
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        "lede": "What sits between the electrodes: liquid, gel and solid electrolytes, their salts, solvents and additives, and the separator that keeps the electrodes apart.",
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        "definition": "A compound added to the electrolyte at a few percent to improve one property — vinylene carbonate and fluoroethylene carbonate build a tougher SEI, others suppress gassing or overcharge. Additive packages are among a cell maker’s closest secrets.",
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        "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.",
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      "id": "term:fec",
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      "label": "Fluoroethylene carbonate",
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        "definition": "A fluorinated additive, sometimes a co-solvent, that forms a lithium-fluoride-rich SEI able to survive the large volume changes of silicon and lithium-metal electrodes. It is almost universal in silicon-blend cells.",
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      "id": "term:cycle-life",
      "type": "Term",
      "label": "Cycle life",
      "properties": {
        "id": "cycle-life",
        "name": "Cycle life",
        "section": "topic-ratings",
        "definition": "The number of full charge–discharge cycles a cell completes before its capacity falls to a stated fraction, usually 80 %, of its initial value under defined conditions. LFP cells reach several thousand cycles; high-energy NMC fewer.",
        "unit": "cycles",
        "related": [
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        "mentions": []
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    },
    {
      "id": "reference:xu-electrolytes",
      "type": "Reference",
      "label": "Electrolytes and Interphases in Li-Ion Batteries and Beyond",
      "properties": {
        "title": "Electrolytes and Interphases in Li-Ion Batteries and Beyond",
        "publisher": "Chemical Reviews",
        "url": "https://doi.org/10.1021/cr500003w",
        "type": "Review article",
        "scope": "Electrolyte salts, solvents, additives and electrode interphases.",
        "year": 2014,
        "authors": [
          "Kang Xu"
        ],
        "accessed": "2026-10-27"
      }
    }
  ]
}