{ "node": { "id": "term:self-discharge", "type": "Term", "label": "Self-discharge", "properties": { "id": "self-discharge", "name": "Self-discharge", "section": "topic-charging", "definition": "The slow loss of stored charge while a cell is not in use. 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In production it is the K-value check; in the laboratory a potentiostatic hold measures the leakage current directly in hours.", "related": [ "self-discharge", "k-value", "open-circuit-voltage", "internal-short-circuit" ], "url": "https://lemonergy.com/learn/glossary/self-discharge-test/", "mentions": [ "chronoamperometry" ] } }, { "id": "lesson:fundamentals/battery-aging/", "type": "Lesson", "label": "Lesson 4 · Battery aging", "properties": { "url": "https://lemonergy.com/learn/fundamentals/battery-aging/" } }, { "id": "visual:self-discharge", "type": "Visual", "label": "Charge retention during storage", "properties": { "title": "Charge retention during storage", "summary": "A constant fractional loss produces an exponential decline.", "readout": "After 6 months: 83.297% retained; after 12: 69.384%.", "formula": "Q(t)/Q₀ = (1 − monthly loss)^t", "note": "Constant fractional loss; chemistry and temperature effects are not modeled.", "software": { "status": "reference", "label": "Reference concept", "body": "This is an illustrative retention model. battery-core aging functions do not estimate self-discharge. Reversible charge loss differs from permanent capacity fade.", "href": "../fundamentals/battery-aging/" }, "html": "
Stored charge retention
Stored charge retentionStorage time (months) versus Fraction of initial charge (%). Charge retained. Interpretation follows the graphs.0025350675910012Storage time (months)Fraction of initialcharge (%)
Charge retained
" } } ] }