{
  "node": {
    "id": "term:long-duration-storage",
    "type": "Term",
    "label": "Long-duration energy storage",
    "properties": {
      "id": "long-duration-storage",
      "name": "Long-duration energy storage",
      "abbr": "LDES",
      "section": "topic-applications",
      "definition": "Storage that discharges for eight hours or more, filling gaps that lithium-ion’s one-to-four-hour systems leave. Flow, iron–air and thermal technologies compete for it by making energy capacity cheap even when power is not.",
      "related": [
        "stationary-storage",
        "flow-battery",
        "e-rate",
        "levelized-cost-of-storage"
      ],
      "url": "https://lemonergy.com/learn/glossary/long-duration-storage/",
      "mentions": []
    }
  },
  "edges": [
    {
      "id": "edge:3146",
      "source": "term:long-duration-storage",
      "target": "topic:topic-applications",
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        "sourceFile": "terms.json"
      }
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      "id": "edge:3147",
      "source": "term:long-duration-storage",
      "target": "term:stationary-storage",
      "type": "relatedTo",
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        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
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    },
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      "id": "edge:3148",
      "source": "term:long-duration-storage",
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      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
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        "sourceFile": "terms.json",
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        "sourceFile": "terms.json",
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      "type": "Topic",
      "label": "Applications and market",
      "properties": {
        "id": "topic-applications",
        "name": "Applications and market",
        "lede": "Where batteries are used, and the terms used to buy, size and compare them.",
        "context": "Start with mission energy, peak power and operating conditions.",
        "example": "20 kWh total energy and a ten-second 100 kW peak constrain different design aspects.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/",
        "lesson_label": "Open energy and power"
      }
    },
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      "id": "term:stationary-storage",
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      "label": "Stationary storage",
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        "id": "stationary-storage",
        "name": "Stationary storage",
        "abbr": "BESS",
        "aka": [
          "battery energy storage system",
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        ],
        "section": "topic-applications",
        "definition": "Batteries installed in a fixed place — a container at a solar farm, a cabinet in a home — to shift energy in time or support the grid. LFP cells dominate because cost per cycle and safety matter more than mass.",
        "related": [
          "lfp",
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        "mentions": []
      }
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    {
      "id": "term:flow-battery",
      "type": "Term",
      "label": "Flow battery",
      "properties": {
        "id": "flow-battery",
        "name": "Flow battery",
        "aka": [
          "vanadium redox flow battery",
          "VRFB"
        ],
        "section": "topic-other-chemistries",
        "definition": "A battery whose energy is stored in liquid electrolytes held in external tanks and pumped through a reaction stack. Energy and power scale independently, which suits long-duration grid storage; vanadium is the most developed chemistry.",
        "related": [
          "stationary-storage",
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        "mentions": []
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      "id": "term:e-rate",
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      "label": "E-rate",
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        "id": "e-rate",
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        "aka": [
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        "section": "topic-ratings",
        "definition": "Power divided by nominal energy, the energy-based cousin of the C-rate: a 1E discharge empties a cell’s watt-hours in one hour. Grid-storage contracts are often written in E-rates or hours of discharge rather than in amperes.",
        "formula": "E-rate = P / E_nominal",
        "unit": "h⁻¹",
        "related": [
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          "nominal-energy",
          "stationary-storage"
        ],
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          "title": "Convert energy rating to power",
          "text": "A 20 kWh battery delivering 10 kW operates at 0.5 h⁻¹, conventionally 0.5E. At constant power with ideal full energy availability, the corresponding duration is 2 h."
        },
        "url": "https://lemonergy.com/learn/glossary/e-rate/",
        "mentions": []
      }
    },
    {
      "id": "term:levelized-cost-of-storage",
      "type": "Term",
      "label": "Levelized cost of storage",
      "properties": {
        "id": "levelized-cost-of-storage",
        "name": "Levelized cost of storage",
        "abbr": "LCOS",
        "section": "topic-applications",
        "definition": "The total lifetime cost of a storage system divided by the total energy it will discharge, in currency per megawatt-hour. It folds cell price, efficiency, cycle life and degradation into one figure for comparing technologies.",
        "unit": "€/MWh",
        "related": [
          "cost-per-kwh",
          "cycle-life",
          "energy-efficiency",
          "stationary-storage"
        ],
        "url": "https://lemonergy.com/learn/glossary/levelized-cost-of-storage/",
        "mentions": []
      }
    },
    {
      "id": "reference:doe-storage",
      "type": "Reference",
      "label": "DOE/EPRI 2013 Electricity Storage Handbook in Collaboration with NRECA",
      "properties": {
        "title": "DOE/EPRI 2013 Electricity Storage Handbook in Collaboration with NRECA",
        "publisher": "Sandia National Laboratories",
        "url": "https://www.sandia.gov/ess/publications/eshb/doe-epri-nreca",
        "type": "Technical handbook",
        "scope": "Storage technologies and grid services. The publisher notes that its historical cost and deployment figures are outdated.",
        "year": 2013,
        "accessed": "2026-10-27"
      }
    }
  ]
}