{
  "node": {
    "id": "term:cycle-life-test",
    "type": "Term",
    "label": "Cycle-life test",
    "properties": {
      "id": "cycle-life-test",
      "name": "Cycle-life test",
      "aka": [
        "cycling test",
        "endurance test"
      ],
      "section": "topic-testing",
      "definition": "Repeating a defined charge and discharge cycle at fixed temperature until capacity reaches the end-of-life criterion, with a reference performance test every few hundred cycles. Conditions — rate, depth of discharge, voltage window, temperature — decide the result, so they are always quoted with it.",
      "related": [
        "cycle-life",
        "reference-performance-test",
        "accelerated-aging",
        "depth-of-discharge",
        "iec-62660"
      ],
      "url": "https://lemonergy.com/learn/glossary/cycle-life-test/",
      "mentions": [
        "voltage-window"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:137",
      "source": "term:cycle-life-test",
      "target": "workflow:cycle-protocol",
      "type": "usedIn",
      "properties": {
        "sourceFile": "wiki-blocks.json"
      }
    },
    {
      "id": "edge:3920",
      "source": "term:cycle-life-test",
      "target": "topic:topic-testing",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:3921",
      "source": "term:cycle-life-test",
      "target": "term:cycle-life",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3922",
      "source": "term:cycle-life-test",
      "target": "term:reference-performance-test",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3923",
      "source": "term:cycle-life-test",
      "target": "term:accelerated-aging",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3924",
      "source": "term:cycle-life-test",
      "target": "term:depth-of-discharge",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:3925",
      "source": "term:cycle-life-test",
      "target": "term:iec-62660",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/cycle-life-test/voltage-window",
      "source": "term:cycle-life-test",
      "target": "term:voltage-window",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:3927",
      "source": "term:cycle-life-test",
      "target": "visual:health",
      "type": "illustratedBy",
      "properties": {
        "sourceFile": "visual-pages.json"
      }
    },
    {
      "id": "edge:3928",
      "source": "term:cycle-life-test",
      "target": "reference:inl-ev-tests",
      "type": "cites",
      "properties": {
        "sourceFile": "wiki-references.json",
        "scope": "direct technical reference"
      }
    }
  ],
  "neighbors": [
    {
      "id": "workflow:cycle-protocol",
      "type": "Workflow",
      "label": "Repeat charge/discharge",
      "properties": {
        "id": "cycle-protocol",
        "title": "Repeat charge/discharge",
        "kind": "protocol",
        "summary": "Cycle aging block repeats charge, discharge and rest.",
        "steps": [
          "Open Cycle aging block.",
          "Review currents and rests; compare throughput."
        ],
        "example": "Twenty 50%-depth discharges give ten discharge-equivalent full cycles at fixed nominal capacity.",
        "observe": "Cycle count differs from throughput.",
        "limits": "Scheduling cycles does not supply calibrated degradation or physical lifetime evidence.",
        "url": "https://design.lemonergy.com/",
        "label": "Open Design → Protocol bench",
        "evidence": [
          "js/test-protocol.js"
        ]
      }
    },
    {
      "id": "topic:topic-testing",
      "type": "Topic",
      "label": "Testing methods",
      "properties": {
        "id": "topic-testing",
        "name": "Testing methods",
        "lede": "The measurements and test procedures that characterise a cell or pack, from capacity and pulse tests to abuse and environmental tests.",
        "context": "Record specimen, state, instrument, temperature and timing.",
        "example": "Resistance immediately after a current step can differ from a ten-second value because slower polarization contributes.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/",
        "lesson_label": "Open capacity measurements"
      }
    },
    {
      "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": [
          "end-of-life",
          "capacity-fade",
          "depth-of-discharge",
          "calendar-life",
          "equivalent-full-cycle",
          "cycle-life-test"
        ],
        "url": "https://lemonergy.com/learn/glossary/cycle-life/",
        "mentions": []
      }
    },
    {
      "id": "term:reference-performance-test",
      "type": "Term",
      "label": "Reference performance test",
      "properties": {
        "id": "reference-performance-test",
        "name": "Reference performance test",
        "abbr": "RPT",
        "aka": [
          "check-up"
        ],
        "section": "topic-testing",
        "definition": "A fixed set of measurements — capacity, resistance by pulse, sometimes impedance — repeated at intervals during an aging test to track state of health under identical conditions. Everything between RPTs is the aging itself.",
        "related": [
          "capacity-test",
          "hppc",
          "state-of-health",
          "accelerated-aging"
        ],
        "url": "https://lemonergy.com/learn/glossary/reference-performance-test/",
        "mentions": [
          "impedance"
        ]
      }
    },
    {
      "id": "term:accelerated-aging",
      "type": "Term",
      "label": "Accelerated aging test",
      "properties": {
        "id": "accelerated-aging",
        "name": "Accelerated aging test",
        "section": "topic-testing",
        "definition": "Aging cells faster than in service — at higher temperature, higher SOC or higher rate — and extrapolating to real conditions with a model such as Arrhenius. The extrapolation only holds if acceleration does not change which mechanism dominates.",
        "related": [
          "arrhenius",
          "calendar-aging",
          "cycle-aging",
          "aging-model",
          "reference-performance-test"
        ],
        "url": "https://lemonergy.com/learn/glossary/accelerated-aging/",
        "mentions": [
          "state-of-charge"
        ]
      }
    },
    {
      "id": "term:depth-of-discharge",
      "type": "Term",
      "label": "Depth of discharge",
      "properties": {
        "id": "depth-of-discharge",
        "name": "Depth of discharge",
        "abbr": "DOD",
        "section": "topic-state",
        "definition": "How much of a cell’s capacity is used in a cycle. Deep cycles cause more mechanical stress in the active materials than shallow ones.",
        "unit": "%",
        "related": [
          "state-of-charge",
          "cycle-life",
          "particle-cracking",
          "usable-capacity"
        ],
        "lesson": "fundamentals/battery-aging/#cracking",
        "url": "https://lemonergy.com/learn/glossary/depth-of-discharge/",
        "mentions": []
      }
    },
    {
      "id": "term:iec-62660",
      "type": "Term",
      "label": "IEC 62660",
      "properties": {
        "id": "iec-62660",
        "name": "IEC 62660",
        "section": "topic-standards-vehicle",
        "definition": "The international standard series for lithium-ion cells in electric vehicles: part 1 performance testing, part 2 reliability and abuse testing, part 3 safety requirements. It fixes test conditions so results from different labs can be compared.",
        "related": [
          "testing",
          "abuse-testing",
          "iso-12405",
          "ul-2580",
          "un-r100",
          "iec"
        ],
        "url": "https://lemonergy.com/learn/glossary/iec-62660/",
        "mentions": []
      }
    },
    {
      "id": "term:voltage-window",
      "type": "Term",
      "label": "Voltage window",
      "properties": {
        "id": "voltage-window",
        "name": "Voltage window",
        "aka": [
          "operating voltage range"
        ],
        "section": "topic-ratings",
        "definition": "The range between a cell’s lower and upper cutoff voltages, such as 2.5–4.2 V for an NMC/graphite cell. Staying inside it is what keeps the electrodes and electrolyte from degrading quickly.",
        "unit": "V",
        "related": [
          "cutoff-voltage",
          "overcharge",
          "over-discharge",
          "electrochemical-stability-window"
        ],
        "url": "https://lemonergy.com/learn/glossary/voltage-window/",
        "mentions": [
          "graphite",
          "electrolyte"
        ]
      }
    },
    {
      "id": "visual:health",
      "type": "Visual",
      "label": "Capacity loss and resistance growth",
      "properties": {
        "title": "Capacity loss and resistance growth",
        "summary": "Energy capability and power capability can degrade differently.",
        "readout": "At the illustrated endpoint: 80% initial capacity and 140% initial resistance.",
        "formula": "Capacity ratio = Q_now/Q_initial; resistance ratio = R_now/R_initial",
        "note": "Chosen qualitative trends. The exposure axis is not predicted cycles or years.",
        "software": {
          "status": "reference",
          "label": "Reference concept",
          "body": "battery-core supplies individual aging relationships, not a calibrated SOH or remaining-life estimator. The selected trends are illustrations and do not predict cycles or years.",
          "href": "../fundamentals/battery-aging/"
        },
        "html": "<figure class=\"visual-figure\"><figcaption>Chosen degradation trends</figcaption><svg class=\"visual-chart\" viewBox=\"0 0 360 330\" role=\"img\" aria-labelledby=\"static-health-0-title static-health-0-desc\"><title id=\"static-health-0-title\">Chosen degradation trends</title><desc id=\"static-health-0-desc\">Relative life exposure versus Relative to beginning of life (%). Capacity retained; Resistance. Interpretation follows the graphs.</desc><path d=\"M74,238h268\" stroke=\"currentColor\" opacity=\".13\"/><text x=\"64\" y=\"242\" text-anchor=\"end\" font-size=\"13\" fill=\"currentColor\">50</text><text x=\"74\" y=\"265\" text-anchor=\"middle\" font-size=\"13\" fill=\"currentColor\">0</text><path d=\"M74,188.5h268\" stroke=\"currentColor\" opacity=\".13\"/><text x=\"64\" y=\"192.5\" text-anchor=\"end\" font-size=\"13\" fill=\"currentColor\">87.5</text><text x=\"141\" y=\"265\" text-anchor=\"middle\" font-size=\"13\" fill=\"currentColor\">0.25</text><path d=\"M74,139h268\" stroke=\"currentColor\" opacity=\".13\"/><text x=\"64\" y=\"143\" text-anchor=\"end\" font-size=\"13\" fill=\"currentColor\">125</text><text x=\"208\" y=\"265\" text-anchor=\"middle\" font-size=\"13\" fill=\"currentColor\">0.5</text><path d=\"M74,89.5h268\" stroke=\"currentColor\" opacity=\".13\"/><text x=\"64\" y=\"93.5\" text-anchor=\"end\" font-size=\"13\" fill=\"currentColor\">163</text><text x=\"275\" y=\"265\" text-anchor=\"middle\" font-size=\"13\" fill=\"currentColor\">0.75</text><path d=\"M74,40h268\" stroke=\"currentColor\" opacity=\".13\"/><text x=\"64\" y=\"44\" text-anchor=\"end\" font-size=\"13\" fill=\"currentColor\">200</text><text x=\"342\" y=\"265\" text-anchor=\"middle\" font-size=\"13\" fill=\"currentColor\">1</text><path d=\"M74,40v198h268\" fill=\"none\" stroke=\"currentColor\" opacity=\".3\"/><polyline fill=\"none\" stroke=\"#2459a8\" stroke-width=\"2.8\" points=\"74.00,172.00 76.68,174.64 79.36,175.73 82.04,176.57 84.72,177.28 87.40,177.90 90.08,178.47 92.76,178.98 95.44,179.47 98.12,179.92 100.80,180.35 103.48,180.76 106.16,181.15 108.84,181.52 111.52,181.88 114.20,182.22 116.88,182.56 119.56,182.88 122.24,183.20 124.92,183.51 127.60,183.81 130.28,184.10 132.96,184.38 135.64,184.66 138.32,184.93 141.00,185.20 143.68,185.46 146.36,185.72 149.04,185.97 151.72,186.22 154.40,186.46 157.08,186.70 159.76,186.93 162.44,187.17 165.12,187.39 167.80,187.62 170.48,187.84 173.16,188.06 175.84,188.27 178.52,188.49 181.20,188.70 183.88,188.90 186.56,189.11 189.24,189.31 191.92,189.51 194.60,189.71 197.28,189.91 199.96,190.10 202.64,190.29 205.32,190.48 208.00,190.67 210.68,190.85 213.36,191.04 216.04,191.22 218.72,191.40 221.40,191.58 224.08,191.76 226.76,191.93 229.44,192.11 232.12,192.28 234.80,192.45 237.48,192.62 240.16,192.79 242.84,192.95 245.52,193.12 248.20,193.28 250.88,193.45 253.56,193.61 256.24,193.77 258.92,193.93 261.60,194.09 264.28,194.25 266.96,194.40 269.64,194.56 272.32,194.71 275.00,194.86 277.68,195.01 280.36,195.17 283.04,195.32 285.72,195.46 288.40,195.61 291.08,195.76 293.76,195.91 296.44,196.05 299.12,196.20 301.80,196.34 304.48,196.48 307.16,196.62 309.84,196.77 312.52,196.91 315.20,197.05 317.88,197.18 320.56,197.32 323.24,197.46 325.92,197.60 328.60,197.73 331.28,197.87 333.96,198.00 336.64,198.13 339.32,198.27 342.00,198.40\"/><polyline fill=\"none\" stroke=\"#a45b2b\" stroke-width=\"2.8\" stroke-dasharray=\"7 4\" points=\"74.00,172.00 76.68,171.47 79.36,170.94 82.04,170.42 84.72,169.89 87.40,169.36 90.08,168.83 92.76,168.30 95.44,167.78 98.12,167.25 100.80,166.72 103.48,166.19 106.16,165.66 108.84,165.14 111.52,164.61 114.20,164.08 116.88,163.55 119.56,163.02 122.24,162.50 124.92,161.97 127.60,161.44 130.28,160.91 132.96,160.38 135.64,159.86 138.32,159.33 141.00,158.80 143.68,158.27 146.36,157.74 149.04,157.22 151.72,156.69 154.40,156.16 157.08,155.63 159.76,155.10 162.44,154.58 165.12,154.05 167.80,153.52 170.48,152.99 173.16,152.46 175.84,151.94 178.52,151.41 181.20,150.88 183.88,150.35 186.56,149.82 189.24,149.30 191.92,148.77 194.60,148.24 197.28,147.71 199.96,147.18 202.64,146.66 205.32,146.13 208.00,145.60 210.68,145.07 213.36,144.54 216.04,144.02 218.72,143.49 221.40,142.96 224.08,142.43 226.76,141.90 229.44,141.38 232.12,140.85 234.80,140.32 237.48,139.79 240.16,139.26 242.84,138.74 245.52,138.21 248.20,137.68 250.88,137.15 253.56,136.62 256.24,136.10 258.92,135.57 261.60,135.04 264.28,134.51 266.96,133.98 269.64,133.46 272.32,132.93 275.00,132.40 277.68,131.87 280.36,131.34 283.04,130.82 285.72,130.29 288.40,129.76 291.08,129.23 293.76,128.70 296.44,128.18 299.12,127.65 301.80,127.12 304.48,126.59 307.16,126.06 309.84,125.54 312.52,125.01 315.20,124.48 317.88,123.95 320.56,123.42 323.24,122.90 325.92,122.37 328.60,121.84 331.28,121.31 333.96,120.78 336.64,120.26 339.32,119.73 342.00,119.20\"/><text transform=\"translate(208 303)\" text-anchor=\"middle\" font-size=\"14\" fill=\"currentColor\"><tspan x=\"0\" dy=\"0\">Relative life exposure</tspan></text><text transform=\"translate(20 139) rotate(-90)\" text-anchor=\"middle\" font-size=\"14\" fill=\"currentColor\"><tspan x=\"0\" dy=\"-8\">Relative to beginning of</tspan><tspan x=\"0\" dy=\"16\">life (%)</tspan></text></svg><div class=\"visual-legend\"><span><i style=\"background:#2459a8\"></i>Capacity retained</span><span><i style=\"background:#a45b2b\"></i>Resistance (dashed)</span></div></figure>"
      }
    },
    {
      "id": "reference:inl-ev-tests",
      "type": "Reference",
      "label": "Battery Test Manual For Electric Vehicles, Revision 3",
      "properties": {
        "title": "Battery Test Manual For Electric Vehicles, Revision 3",
        "publisher": "Idaho National Laboratory",
        "url": "https://inldigitallibrary.inl.gov/sites/sti/sti/6492291.pdf",
        "type": "Test manual",
        "scope": "Performance characterization, pulse resistance/power, life testing and reference performance tests; historical 2015 edition.",
        "year": 2015,
        "authors": [
          "Jon P. Christopherson"
        ],
        "accessed": "2026-10-27"
      }
    }
  ]
}
