Toshiba T1100 - Battery
IMPORTANT: T1100, not the T1100 PLUS
Rechargeable 12V battery, consisting of ten 1.2V 1200mAh NiCd cells wired in series.
NiCd cells, when new, charge to about 1.3V, and so, when new, the battery would have been charging up to about 13V.
Some additional information about the battery, including ways of bypassing a missing or faulty battery, is at here.