{ "node": { "id": "term:capacity-test", "type": "Term", "label": "Capacity test", "properties": { "id": "capacity-test", "name": "Capacity test", "section": "topic-testing", "definition": "A defined capacity test with specified charge, rest, discharge and cutoff conditions, usually a full CC-CV charge, a rest, and a C/3 or lower discharge to the lower cutoff at 25 °C. 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The result is the rate-capability curve on a datasheet and the first sign of a transport limitation.", "related": [ "rate-capability", "c-rate", "capacity-test", "ideal-duration", "peukert" ], "url": "https://lemonergy.com/learn/glossary/rate-test/", "mentions": [ "datasheet" ] } }, { "id": "lesson:fundamentals/capacity-and-c-rate/", "type": "Lesson", "label": "Lesson 2 · Capacity and C-rate", "properties": { "url": "https://lemonergy.com/learn/fundamentals/capacity-and-c-rate/" } }, { "id": "visual:capacity", "type": "Visual", "label": "C-rate, current and duration", "properties": { "title": "C-rate, current and duration", "summary": "A C-rate becomes an actual current only when capacity is known.", "readout": "5 Ah × 1C = 5 A. Ideal duration: 1 h (60 min).", "formula": "I = Q × C-rate; t_ideal = 1 / C-rate", "note": "Voltage cutoff, losses, temperature and rate-dependent capacity are excluded.", "software": { "status": "implemented", "label": "Implemented in battery-core", "body": "current_from_c_rate calculates I = Q × C-rate; ideal_duration_hours calculates 1 / C-rate. Neither predicts voltage-cutoff time or real usable capacity.", "href": "../fundamentals/capacity-and-c-rate/" }, "html": "
Ideal remaining charge
Ideal remaining chargeTime (h) versus Remaining charge (Ah). 1C. Interpretation follows the graphs.001.2512.523.75354Time (h)Remaining charge (Ah)
1C
" } }, { "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" } }, { "id": "reference:sandia-performance", "type": "Reference", "label": "DOE Energy Storage Handbook, Chapter 16: Energy Storage Performance Testing", "properties": { "title": "DOE Energy Storage Handbook, Chapter 16: Energy Storage Performance Testing", "publisher": "Sandia National Laboratories", "url": "https://www.sandia.gov/app/uploads/sites/163/2021/09/ESHB_Ch16_Testing_Rosewater.pdf", "type": "Technical handbook chapter", "scope": "Section 2.1.2.1 explains capacity, C-rate and the distinction between capacity and energy; also covers pulse characterization.", "accessed": "2026-10-27" } } ] }