A question for the group from someone who admits to knowing little
about batteries:

My glider is setup with two 12v9ah (the new "same size as the 7.5ah"
ones) batteries, with each normally powering half my electronics; i.e
one batt is powering the radio and SN10/GPS, while the other runs the
logger/GPS, PDA, and backup vario. Each is connected via a 3-way
master switch, so either battery can power either or both "busses".

This setup does not allow both batteries to be connected to the same
"bus" at the same time. On the rare time I've had to switch due to old
or insufficiently charged batteries, I've had no trouble with the
traces from the loggers.

My question is, is this better, equal, or worse (from the standpoint of
battery usage/efficiency) than the more common "use one batt until it
dies, then switch" 2-battery setup.

TIA,

Kirk
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