Do your 18650's charge to exactly 4.2 volts?

[Scy123]

Anyone know whether that's legit - that a battery will begin to lose "capacity" due to age?

Oh it's legit. At least for 18650s.

 

[bwh79]

I always run no closer than 10 amps to limit i.e 10 amps on a 20 amp battery so I should be fine right? I didn't think it was a huge issue but I wanted to check nonetheless

So let's see, so you're building at around .42 then, right? Amps = Volts / Ohms so we're looking at 4.2 volts / .42 ohms = 10 amps. Now what happens if the battery charges up a little more. You're saying it'll go up to 4.22 or 4.24, but let's just say it goes up a full tenth of an ohm, all the way to 4.3 volts: 4.3 / .42 = 10.2380....., I think you're still pretty well within the safety margin, there. How confident are you in your ohm-reader's accuracy? If it's off by even one one-hundredth and your build is actually .41 ohms instead of .42, the amps are already higher at 10.2439.... than they are by charging the battery an extra tenth of a volt. I don't know how good that is for the battery, but as far as your question regarding amp limits is concerned, it's nothing to get twisted up about.

 

[MattyVigilante]

So let's see, so you're building at around .42 then, right? Amps = Volts / Ohms so we're looking at 4.2 volts / .42 ohms = 10 amps. Now what happens if the battery charges up a little more. You're saying it'll go up to 4.22 or 4.24, but let's just say it goes up a full tenth of oan ohm, all the way to 4.3 volts: 4.3 / .42 = 10.2380....., I think you're still pretty well within the safety margin, there. How confident are you in your ohm-reader's accuracy? If it's off by even one one-hundredth and your build is actually .41 ohms instead of .42, the amps are already higher at 10.2439.... than they are by charging the battery an extra tenth of a volt. I don't know how good that is for the battery, but as far as your question regarding amp limits is concerned, it's nothing to get twisted up about.

That's pretty much my exact situation
I am confident in my ohm meter, I've checked the current build on 2 different regulated mods as well as the ohm meter and they all say exactly the same.
I figured the same as what you say, I'm not worried about the amp limit, more about how good it is for the battery. I'm not too fussed even about the batteries I am using now, but I have got new, good quality ones on the way and would like to give them the best chance at a long life as they weren't exactly cheap!