摘要 |
<p>A method and apparatus for measuring the electrical efficacy of one or more battery cells for use in an uninterruptable power supply are disclosed. The efficacy is determined by making use of the ripple current which flows in the battery cells when in use in the uninterruptable power supply. Simultaneous measurement, for example, of the ripple current and a corresponding voltage component enables the internal impedance of a battery cell to be determined, the impedance acting as an indicator of electrical efficacy.</p> |