Thread: Battery life?
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Unread 05-05-2011, 08:29
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Re: Battery life?

clarification...

Al's comment on 2v drop refers to a rested battery after charge under NO load..

Graph of data taken show TWO quick declines:

.. the first is surface charge and exists from 13.3 down to 12.7 or so under low load dissipates in 3 minutes.. under no load can exist for hours

.. the second upon 50A load declines immediately and is due to Batt internal resistance.. Vdrop = .02*50A =1v

.. then holds relatively unchanged until the battery is exhausted and again drops off quickly (decline#3) as the internal resistance rises to & >.1 ohm

... de K3MNN originally from Pittsburgh PA --... ...--