I clean the contacts of my mods about once every 2 month with a little bit of metal polish. It has been working well so far. My problem is the batteries. There are marks where the contact points of the mod touches them. Can I clean that with metal polish as well? I tried scratching them out with my fingernails but it doesn't work. If I can't use metal polish then what other cleaning agent can I use? Thanks in advance.
I'll assume you're talking about mechanical mods, correct me if I got that wrong. I use alcohol on contact surfaces and if I feel they need it some 600 grit sandpaper or emery cloth
very gently. I have one mod in particular that pits the positive battery contact. I used to gently use the fine sandpaper on them occasionally, but there was no change in performance when I did that so I stopped the practice. IMO it was just adding more wear to the surfaces.
Batteries should last you at least 300 charge cycles, however long that takes within about a six year window, so the amount of time that you've had them doesn't really mean much. As they age their internal resistance goes up causing a decrease in mAh (less run time on a charge) and an increase in voltage drop under load (less power in a mechanical mod). The more you stress batteries the faster they age. Running then at high amp draw, using them until they are at voltage before recharging, letting them sit for days fully charged, running them hot will all accelerate the aging process.