The real-time-clock battery port is intended to connect to a CR2032 or similar battery.
There exists the LiCR2032 cell, which is a small lithium-ion battery in the CD2032 form factor, which means the battery can keep being re-charged and will "never" run out assuming it's charged now and then. (Another option here is a supercap, but I'm not going that way right now.)
The charging voltage of a Lithium battery may be as high as 4.3V, somewhat depending on chemistry.
Does the VBAT of the Teensy 3.5 accept the 4.3V of a fully-charged LiCR2032 battery, or is that voltage too high?
(Separately, the actual current draw on the 3.2V CR2032 will likely be low enough that a single non-rechargeable battery should last "long enough" anyway -- that may be the better engineering solution overall, but that's also not what this question is about
There exists the LiCR2032 cell, which is a small lithium-ion battery in the CD2032 form factor, which means the battery can keep being re-charged and will "never" run out assuming it's charged now and then. (Another option here is a supercap, but I'm not going that way right now.)
The charging voltage of a Lithium battery may be as high as 4.3V, somewhat depending on chemistry.
Does the VBAT of the Teensy 3.5 accept the 4.3V of a fully-charged LiCR2032 battery, or is that voltage too high?
(Separately, the actual current draw on the 3.2V CR2032 will likely be low enough that a single non-rechargeable battery should last "long enough" anyway -- that may be the better engineering solution overall, but that's also not what this question is about
