The decline in charge a battery can deliver compared with its original rated capacity.
Capacity fade tracks how battery charge-delivery capability changes over time and use at rated voltage. For covered batteries it is one of the documented durability parameters. Read a reported value alongside its baseline and test conditions rather than treating it as a complete judgement of reuse suitability.
Capacity fade is the measured reduction in charge deliverable at rated voltage against the battery’s original rated capacity.
Not an instantaneous state-of-charge reading.
Battery Regulation Annex IV defines the measure against original rated capacity; the source definition is distinct from state of charge.
EU Battery Regulation
‘Capacity fade’ means the decrease over time and upon usage in the amount of charge that a battery can deliver at the rated voltage, with respect to the original rated capacity.
Formal definition in the cited source and edition; scope and application follow that instrument. Consolidated EUR-Lex text is a documentation tool; the Official Journal text is authentic.
Reference: Annex IV, definition (2)
Officially defined in the cited source. The verbatim source passage is shown separately from Minespider’s explanatory text; applicability follows that source.
Record original rated capacity, measured charge-delivery value, rated-voltage conditions, date and test evidence.
A reported fade value is usable only alongside its baseline capacity, test conditions and measurement date.
Source anchor; see source context and definition status.
Open reference