Considering bumping Mail Chime 12vdc to 14.4vdc

https://www.amazon.com/Mail-Chime-MAIL-1200-Wireless-System/dp/B00103FDDU

Original thread here:

My mailbox is located about 300 ft from the receiver.

I'm heavily invested in 1.2v li-on Eneloops and use them (if I can't convert it to USB, which is my preference). The mod works pretty well until the temperatures get around freezing. I should probably add a remotely located 12vdc solar panel after this .