[DuoList] Pram battery question...

[Samual Acorn]

finally took apart and repaired my 280c (no dremel was involved)  but
in the process removed the pram battery to avoid any leakage (just in
case) and.. out of curiosity.. dismantle it.. (its dead anyway)...
discovered it was 2 Panasonic UL2330 regargable 3v lithium coin
cells... problem is... theres 3 wires to it.. the two coin cells are
stacked and there is a red on the '+' of the first and a black on the
'-' of the second... but a white inbetween the two... the only thing i
could think of for such is the batteries are charged differently than
they are used... so my question is; are they charged in parallel and
used in series or vice versa? or am i completely off whack and the
white wire does something different alltogether... ?