{ "node": { "id": "term:intermittent-current-interruption", "type": "Term", "label": "Intermittent current interruption", "properties": { "id": "intermittent-current-interruption", "name": "Intermittent current interruption", "abbr": "ICI", "aka": [ "current interruption method" ], "section": "topic-testing", "definition": "Pausing the current for a few seconds every few minutes during a slow constant-current cycle and fitting the voltage response against the square root of time. The instant jump gives internal resistance and the slope a diffusion resistance, mapped across the whole state-of-charge range in a single cycle — a fast alternative to GITT.", "related": [ "gitt", "internal-resistance", "diffusion-coefficient", "warburg-impedance", "dcir" ], "url": "https://lemonergy.com/learn/glossary/intermittent-current-interruption/", "mentions": [ "diffusion" ] } }, "edges": [ { "id": "edge:5370", "source": "term:intermittent-current-interruption", "target": "topic:topic-testing", "type": "belongsTo", "properties": { "sourceFile": "terms.json" } }, { "id": "edge:5371", "source": "term:intermittent-current-interruption", "target": "term:gitt", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:5372", "source": "term:intermittent-current-interruption", "target": "term:internal-resistance", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:5373", "source": "term:intermittent-current-interruption", "target": "term:diffusion-coefficient", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:5374", "source": "term:intermittent-current-interruption", "target": "term:warburg-impedance", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:5375", "source": "term:intermittent-current-interruption", "target": "term:dcir", "type": "relatedTo", "properties": { "sourceFile": "terms.json", "meaning": "Related context; not a causal claim" } }, { "id": "edge:mentions/intermittent-current-interruption/diffusion", "source": "term:intermittent-current-interruption", "target": "term:diffusion", "type": "mentions", "properties": { "sourceFile": "terms.json", "method": "build_glossary.mention_index + mentions", "field": "definition", "meaning": "Text mention; not a causal claim" } }, { "id": "edge:5377", "source": "term:intermittent-current-interruption", "target": "visual:rc", "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:gitt", "type": "Term", "label": "Galvanostatic intermittent titration technique", "properties": { "id": "gitt", "name": "Galvanostatic intermittent titration technique", "abbr": "GITT", "section": "topic-testing", "definition": "A series of short constant-current pulses each followed by a long rest, so that both the equilibrium voltage curve and the solid diffusion coefficient can be extracted at each state of charge. 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Its slope and onset frequency give a route to the diffusion coefficient.", "related": [ "randles-circuit", "nyquist-plot", "diffusion-coefficient", "electrochemical-impedance-spectroscopy" ], "url": "https://lemonergy.com/learn/glossary/warburg-impedance/", "mentions": [ "impedance", "diffusion" ] } }, { "id": "term:dcir", "type": "Term", "label": "DC internal resistance", "properties": { "id": "dcir", "name": "DC internal resistance", "abbr": "DCIR", "aka": [ "DC-IR", "pulse resistance" ], "section": "topic-testing", "definition": "Internal resistance measured from the voltage change during a current pulse of defined length, usually 10 s or 18 s. 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In a cell lithium diffuses through the electrolyte in the pores and, far more slowly, through the solid particles themselves.", "related": [ "ficks-first-law", "diffusion-coefficient", "solid-state-diffusion", "concentration-gradient", "migration" ], "lesson": "transport/ficks-first-law/#in-a-cell", "url": "https://lemonergy.com/learn/glossary/diffusion/", "mentions": [ "electrolyte" ] } }, { "id": "visual:rc", "type": "Visual", "label": "Voltage response and relaxation", "properties": { "title": "Voltage response and relaxation", "summary": "One time constant completes about 63% of a first-order voltage change.", "readout": "At τ = 20 s, 63.2% of the step response is complete; a relaxation retains 36.8%.", "formula": "τ = RC; step response = 1 − e^(−t/τ)", "note": "Two separate analytical experiments; normalized voltage, not measured data.", "software": { "status": "reference", "label": "Reference concept", "body": "An analytical RC response explains polarization and relaxation. It is not an identified RC network or a native Studio battery capability.", "href": "../chapter-1/" }, "html": "
First-order voltage response
First-order voltage responseTime (s) versus Fraction of voltage change. Step response; Separate relaxation experiment. Interpretation follows the graphs.000.263450.525900.7881351.05180Time (s)Fraction of voltagechange
Step responseSeparate relaxation experiment (dashed)
" } } ] }