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An unexpected rise can signal a leakage path or a soft internal short.", "unit": "%/month", "related": [ "internal-short-circuit", "calendar-aging", "k-value", "calendar-life", "self-discharge-test" ], "lesson": "fundamentals/battery-aging/#check-yourself", "url": "https://lemonergy.com/learn/glossary/self-discharge/", "mentions": [] } }, { "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" ] } }, { "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)
" } } ] }