Battery Change ?

Hi all
New to site
.. just bought my very first Mx5 a 1998 1.8 jap import in BRG with tan leather in auto ...love it.
Have noticed that when starting her car first thing in the morning the battery is not turning over the engine vigorously enough
so went to check/top up battery but there is what looks like a water top up system in place, lots of transparent tubes going into where you
would normally pop off the plastic covers and expose the plastic nuts that screw/prise off.
Decided to not touch as I have never seen anything like it before.. can anyone advise ?
Cheers Warren
New to site

Have noticed that when starting her car first thing in the morning the battery is not turning over the engine vigorously enough
so went to check/top up battery but there is what looks like a water top up system in place, lots of transparent tubes going into where you
would normally pop off the plastic covers and expose the plastic nuts that screw/prise off.
Decided to not touch as I have never seen anything like it before.. can anyone advise ?
Cheers Warren