Re: D105 Battery Time
Find the least-expensive lawn and garden battery that you can find. If you are near Costco, they carry an Interstate one for about $33.
Just make sure that you are getting a fresh battery, and not one that's a year old that's been sitting on the shelf for the past year w/o being charged. There is usually a date sticker, and also the alphanumeric date is burned into the side of the case (google-image "battery date code") if you can't find the sticker on it.
Buy the freshest battery that you can find. I've also found that in many cases, the seal between the top of the case and the terminals on these small lawn-and-garden batteries is not very good, allowing acid to creep up onto the terminals and corrode them. So what I do when I get a new battery, is to take some sort of sealant (silicone RTV, Permatex #2, or whatever I have handy at the time), and place a small bead of it all around each terminal where it comes through the case. This will keep your terminals much happier.