{ "node": { "id": "term:capacity-fade", "type": "Term", "label": "Capacity fade", "properties": { "id": "capacity-fade", "name": "Capacity fade", "section": "topic-aging", "definition": "The loss of charge a cell can store and deliver, for example through lithium locked into the SEI or active material that has cracked out of service.", "related": [ "loss-of-lithium-inventory", "loss-of-active-material", "state-of-health", "knee-point" ], "lesson": "fundamentals/battery-aging/#chain", "url": "https://lemonergy.com/learn/glossary/capacity-fade/", "mentions": [ "active-material", "sei" ] } }, "edges": [ { "id": "edge:1387", "source": "term:capacity-fade", "target": "topic:topic-aging", "type": "belongsTo", "properties": { "sourceFile": "terms.json" } }, { "id": "edge:1388", "source": "term:capacity-fade", "target": "term:loss-of-lithium-inventory", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1389", "source": "term:capacity-fade", "target": "term:loss-of-active-material", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1390", "source": "term:capacity-fade", "target": "term:state-of-health", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:1391", "source": "term:capacity-fade", "target": "term:knee-point", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:mentions/capacity-fade/active-material", "source": "term:capacity-fade", "target": "term:active-material", "type": "mentions", "properties": { "sourceFile": "terms.json", "method": "build_glossary.mention_index + mentions", "field": "definition", "meaning": "Text mention; not a causal claim" } }, { "id": "edge:mentions/capacity-fade/sei", "source": "term:capacity-fade", "target": "term:sei", "type": "mentions", "properties": { "sourceFile": "terms.json", "method": "build_glossary.mention_index + mentions", "field": "definition", "meaning": "Text mention; not a causal claim" } }, { "id": "edge:1394", "source": "term:capacity-fade", "target": "lesson:fundamentals/battery-aging/", "type": "explainedIn", "properties": { "sourceFile": "terms.json", "url": "https://lemonergy.com/learn/fundamentals/battery-aging/#chain" } }, { "id": "edge:1395", "source": "term:capacity-fade", "target": "visual:health", "type": "illustratedBy", "properties": { "sourceFile": "visual-pages.json" } }, { "id": "edge:1396", "source": "term:capacity-fade", "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: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. 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It usually marks the onset of lithium plating or electrolyte dry-out, and a cell past its knee is unpredictable and should be retired.", "related": [ "capacity-fade", "lithium-plating", "electrolyte-dry-out", "remaining-useful-life", "end-of-life" ], "url": "https://lemonergy.com/learn/glossary/knee-point/", "mentions": [ "electrolyte" ] } }, { "id": "term:active-material", "type": "Term", "label": "Active material", "properties": { "id": "active-material", "name": "Active material", "abbr": "AM", "section": "topic-components", "definition": "The part of an electrode that actually stores lithium — graphite on the negative side, an oxide or phosphate on the positive. 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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": "
Chosen degradation trends
Chosen degradation trendsRelative life exposure versus Relative to beginning of life (%). Capacity retained; Resistance. Interpretation follows the graphs.50087.50.251250.51630.752001Relative life exposureRelative to beginning oflife (%)
Capacity retainedResistance (dashed)
" } }, { "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" } } ] }