I have a mod that I thought had a damaged chip/PCB. Well it turns out that the spring on the positive battery post has merely gotten weak causing the battery to not contact well and therefore causing the the mod to act funny (when battery gets to about 3.8v or lower, mod just restarts itself when you press the fire button). I took a strong, thin (1mm thick) magnet and placed it on the negative post of the battery then screwed the cap on and VOILA! - the mod now works as it should regardless if the battery is above or below 3.8V - works just like new, in fact. So how do I extend the length of the battery by about 1mm without using a magnet? I looked for 1mm battery extenders, but came up short. EDITED TO ADD: I'm not a big fan of putting a blob of solder on a battery terminal. Looking for a more versatile solution, like an extender, so I can still use the battery on other mods without sizing issues.