{ "node": { "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" ] } }, "edges": [ { "id": "edge:2717", "source": "term:accelerated-aging", "target": "topic:topic-testing", "type": "belongsTo", "properties": { "sourceFile": "terms.json" } }, { "id": "edge:2718", "source": "term:accelerated-aging", "target": "term:arrhenius", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:2719", "source": "term:accelerated-aging", "target": "term:calendar-aging", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:2720", "source": "term:accelerated-aging", "target": "term:cycle-aging", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:2721", "source": "term:accelerated-aging", "target": "term:aging-model", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:2722", "source": "term:accelerated-aging", "target": "term:reference-performance-test", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:mentions/accelerated-aging/state-of-charge", "source": "term:accelerated-aging", "target": "term:state-of-charge", "type": "mentions", "properties": { "sourceFile": "terms.json", "method": "build_glossary.mention_index + mentions", "field": "definition", "meaning": "Text mention; not a causal claim" } }, { "id": "edge:2724", "source": "term:accelerated-aging", "target": "visual:arrhenius", "type": "illustratedBy", "properties": { "sourceFile": "visual-pages.json" } } ], "neighbors": [ { "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:arrhenius", "type": "Term", "label": "Arrhenius law", "properties": { "id": "arrhenius", "name": "Arrhenius law", "section": "topic-aging", "definition": "The rule that a rate constant is proportional to exp(−Ea/RT), so a thermally activated reaction speeds up steeply with temperature. 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A different estimate of available capacity changes this percentage, so compare SOC values only with the capacity convention recorded." }, "url": "https://lemonergy.com/learn/glossary/state-of-charge/", "mentions": [ "usable-capacity" ] } }, { "id": "visual:arrhenius", "type": "Visual", "label": "Temperature and reaction rate", "properties": { "title": "Temperature and reaction rate", "summary": "Compare an activated process with its rate at 25 °C.", "readout": "At 25 °C: 1×. At 35 °C: 1.924×. At 45 °C: 3.554×.", "formula": "k(T)/k(T_ref) = exp[(Eₐ/R)(1/T_ref − 1/T)]", "note": "The equation uses kelvin. One activated process is represented, not lifetime.", "software": { "status": "implemented", "label": "Implemented in battery-core", "body": "arrhenius_factor returns a rate multiplier from temperature and activation energy. It does not predict cell lifetime.", "href": "../fundamentals/battery-aging/" }, "html": "
Relative reaction rate
Relative reaction rateTemperature (°C) versus Rate multiplier (×). Relative to 25 °C. Interpretation follows the graphs.002.18154.37306.55458.7460Temperature (°C)Rate multiplier (×)
Relative to 25 °C
" } } ] }