Just use the Nyko Power Pack+. It works just fine for that, it also gives you better battery life then the battery that comes with the 3ds (Witch is garbage by the way. Seriously only 3 hours of battery life!? Wtf Nintendo!!!) You will at least get very good battery life if you have power saving mode on and the brightness set to 3 on the 3ds. It lasted a long time for me. (My guess is about 6 hours) but I'm not sure though. I never play that thing all day, and every hour so I don't know. But I always charge it at night. (Thats normally when my 3ds battery gets low.) The point is, just get that, its a two in one solution. You get better battery life and two grips on the back. I recommend it.