Ok - help me understand - the penny finally dropped that you mentioned plating.
You're saying that the higher voltage creates a state where either electroplating or reverse electroplating occurs.
I'm not clear that (reverse)electroplating has a thermal by-product. (I reverse electroplate things, but never bothered to check temp.)
Hmmm.
If I understood correctly, the capacity is nominally 3700 mV and 4200 mV is the upper tolerance.
I didn't see the plating comment, so maybe I am missing something?
You understand the voltage rating correctly, at least from my perspective and experience. 4200mv would be the upper tolerance, and devices and/or chargers should have that regulation and limit built into them already, just as I am sure the 3D does. With the high voltage, there shouldn't be much heating once full charge is reached and there is little activity on the phone, because the battery has reached capacity and their is no real current flowing through it.
The voltage (and heating that seems associated with it) seems to effect the minority of phones (based on the polling here) so the regulated charging must be working properly on most devices, even though the voltage reads as high. As to the voltage readings being reported incorrectly by the phone, I think that it's something possible but with what I have available to work with (1 Evo 3D and it's battery) and voltage reading and charging tools, on my phone it appears to read correctly.
LiIon technology is so complicated I hate trying to dive too deep into it because it then goes beyond my experience and comfort to speak about, and I don't want to be making guesses. A LOT of engineering goes into LiIon batteries and the devices that run them, because of the great power of LiIon and the "control" necessary to charge them.
When Alkaline, NiMh and other older technologies stray outside of their voltage range, they stay pretty stable. LiIon and Lithium Polymer much less so. NOT that they are randomly dangerous or volatile, they just require more care. Normally we never think about it, because the phone takes care of everything for you and we don't give the battery a second thought. You can't simply plug a LiIon battery into a wall without a regulated charger, which in our case is mostly the phone. In RC applications I've seen what happens when batteries are used outside of the set range. Phone batteries AREN'T RC batteries but they use the same technology and require the same care... so when I see the voltage on my phones battery outside of that "set" range, it naturally makes me question why.
I am far from an expert on LiIon batteries or phone charging technology... I am not a chemist or engineer. I'm hoping to hear or get input from somebody who is. I just want my phone to work normally.
