Obvious "green" question - but want to be sure - Car Battery Safety
 

I have a 99 S70 T-5 w/90K miles - and my ? involves recently finding a light amt of clear fluid on top of my car battery - it has (3) diodes (is that what they're called?) Not sure what to call them, but they're located on top of the battery, but it is NOT the terminal connectors, they are (3) small (quarter size) circular areas (closed in it looks like), on top of the battery on the opposite side of the terminals.

Anyways, 2 of the 3 areas appear to be leaking, and it is allegedly a 'maintenance-free' battery - I've had it for about 2 years roughly, but wanted to ask anyone if they thought this was potentially an issue - safety, etc.? The car starts fine, though I will say that it seems that my heat isn't as hot as it once was, and that is a separate issue I know - blower motor is fine, just no heat, but didn't want to be driving a car with a potentially dangerous battery issue. Thanks all for your help -