I recommend you buy a new battery with higher capacity, it should help (atleast it did with me)

3ds got pretty old nowdays i dont think that hb is the problem. try ordering a new bat on amazon. im getting a upgrade to

nimtendo support said it may have proformence issues from modding!

i still get about 4 hours out of my 3ds

well before modding it ran at least half a day, now i maybe get 1½ hours.. maybe a new battery really might help. thank yall for the replies!

i think it may be worth looking for a new battery, i haven't noticed any fast drain on mine unless im downloading something