ok this isn't exactly a antenna question but hope it's ok

I have a super powergate ... and a 8g27 gel battery

i got a battery from a friend a smaller 25am battery , cant figure out
the chemestry but seems like agm

so the battery is smaller sized, and perhaps/probably different type(not
gel )

i therefore presumed i couldn't parrallel them as they would get
different charge rates and poof

but someone said that it's ok and each battery will just draw what it
needs as it's resistance changes (presuming that both batteries were
at equal Volts when i hook them up initially to avoid bat a charging bat
b


but unsure and feel i should double check a 8g27 blowing up in the
house wouldn't be fun


thanks