For less than $70 you can get tid of all your batteries and power everything off a wallwart. I haven't used a battery in any of my active basses or pedals in over 3 years. There are a number of threads about how to eliminate batteries or you can PM me for details.
Clubs: BTB 118, Ibanez 689, 5-string 436, P&W 820, Lefties who play Rightie 157
BTB675, EDB605, GSR200, Ibanez Promethean 210, GK MB500, OB-110