JJ 14 V battery.If I remember right the battery took 9 AA battery's and I asked them to use 24ah with no memory effect because they come with min. ah battery's. It now charges in less than an hr. instead of 3 or 4 and lasts twice as long. The drill was given to me new and the name is warn off ( a cheep drill) I personally only buy Makita drills. The new 4ah ion lith have plenty of power but only owned them 1 yr. so don't know how well they'll last. The NC battery's with memory effect have the longest life span of any I own and in my Agatec lazer level 10 yrs. old still will operate it for 40 hrs.between charges.