the data sheet says
If the Timer1 oscillator will be used as the clock source
for the RTCC, make sure to enable it by setting
T1CON<3> (T1OSCEN). The selected RTC clock can
be brought out to the RTCC pin by the
RTSECSEL<1:0> bits in the PADCFG register.
which is missing in your code
T1CON = %10000101
try
T1CON = %10001101