{ "node": { "id": "term:hppc", "type": "Term", "label": "Hybrid pulse power characterisation", "properties": { "id": "hppc", "name": "Hybrid pulse power characterisation", "abbr": "HPPC", "section": "topic-testing", "definition": "A test that applies a short discharge pulse and a short charge pulse at each state of charge, from which resistance and power capability are read as a function of SOC. 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Its few parameters are fitted from pulse tests, and it is what most battery management systems run in real time.", "related": [ "rc-pair", "open-circuit-voltage", "hppc", "kalman-filter", "single-particle-model" ], "url": "https://lemonergy.com/learn/glossary/equivalent-circuit-model/", "mentions": [] } }, { "id": "term:state-of-power", "type": "Term", "label": "State of power", "properties": { "id": "state-of-power", "name": "State of power", "abbr": "SOP", "section": "topic-state", "definition": "The maximum charge or discharge power a battery can deliver for the next few seconds without breaking a voltage, current or temperature limit. The BMS recomputes it continuously from SOC, temperature and resistance and sends it to the motor controller.", "unit": "W", "related": [ "power", "state-of-charge", "continuous-current", "derating", "bms", "state-of-function" ], "url": "https://lemonergy.com/learn/glossary/state-of-power/", "mentions": [] } }, { "id": "term:internal-resistance", "type": "Term", "label": "Internal resistance", "properties": { "id": "internal-resistance", "name": "Internal resistance", "abbr": "IR", "aka": [ "DC resistance", "DCIR" ], "section": "topic-units", "definition": "The resistance a cell presents to current, from its foils, electrolyte, interfaces and the reactions themselves. 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The instant voltage step gives the ohmic resistance, the following curve the slower polarization; HPPC is a standardised sequence of such pulses across state of charge.", "related": [ "hppc", "dcir", "internal-resistance", "relaxation", "equivalent-circuit-model" ], "url": "https://lemonergy.com/learn/glossary/pulse-test/", "mentions": [ "polarization", "state-of-charge" ] } }, { "id": "term:state-of-charge", "type": "Term", "label": "State of charge", "properties": { "id": "state-of-charge", "name": "State of charge", "abbr": "SOC", "section": "topic-state", "definition": "How full a cell is, as a fraction of its available capacity. 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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: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)
" } }, { "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" } } ] }