While I do not personally do my own maintenance (no garage, no jackstands, no nearby oil disposal site), cleaning the battery filter is definitely something I can do myself. It's a matter of opening a panel, removing a little cover and sliding the filter out. It can be done in about fifteen seconds.

I highly recommend familiarizing one's self with the filter's location. Habitually removing it every few months is a good idea IMO. Tap it against the curb or ground to clear it of any leaves or bugs that have been sucked into the intake. Most of the dirt will also come off.

I was surprised how much stuff was in there after just 3 month's driving.