A control apparatus for an on-vehicle electricity storage device, which enables
an appropriate charging of the on-vehicle electricity storage device while preventing
degradation of the on-vehicle electricity storage device. The counter value of
a high voltage maintaining counter CVB14V and the timer value of a sustain
time subtraction timer TACG2 are increased over the period after time t1
in which the inter-terminal voltage VB of the battery is maintained to be greater
than the predetermined mode switching threshold voltage #VB14V. The counter
value and the timer value decrease over the period from time t2 to time
t3. At time t3, the operation mode is switched from a non-charging
mode to a charging mode.
