I resurrected 6x 18650 batteries from a laptop battery , there is nickel connecting the batteries and where a + and - connection should be I soldered on copper wire. Each battery is charged. One is at 3.82v and the other 2 are at 4.2v. I am using them to mod my nerf rival gun which needs a minimal of 9v to turn on , 10v to fire. Anyways, when I connected the terminals together the power sounded way too low. So when I checked the batteries it only read 3.82v . I checked each battery and terminal but they are all fine. Right now I don’t have much money and I cant buy a new power supply for my gun. What do I do? I’ll add a picture if the power pack in about 7-9 hours.