- Definition
- Rated capacity is the minimum capacity a cell or battery is guaranteed to deliver under the conditions stated in its specification, and it is always equal to or lower than the typical capacity quoted for the same product.
This page defines the term. For what it means in practice, see Power bank capacity claims: what a mAh rating actually means.
Two numbers, one cell
Manufacturers publish two capacity figures for the same cell. The typical capacity is the average across a production batch. The rated capacity is the floor: the figure the manufacturer guarantees every cell in the batch will meet.
The rated figure is the one that matters when a specification is being met, because it is the number the supplier is contractually committed to. The typical figure is the one that appears in marketing, because it is larger.
Three different numbers get called "capacity"
A power bank described as "20,000 mAh" may be quoting the typical cell capacity, the rated cell capacity, or the energy available at the output after conversion. These are three different figures, and the third is always the smallest of the three.