Saw the idea of a node hidden in an On! can on YouTube and decided I wanted to make my own.
Since the lil coil antenna has a very solid SWR and fits in the smaller section, I figured I'd go with the biggest battery I can fit in the can with a Rak4631, which turns out to be a 102540 (10mm x 25mm x 40mm). I spliced a JST PH2 onto so I can still use the balanced charger that came with the battery since that uses a JST PH1.25.
Thought I'd share the two Heltec V3s I have since I've been enjoying the hobby.
The larger case has a 3000mAh battery in it, while the smaller has an 1100mAh battery. Both antennas I tuned myself since they were off by a good bit. ATM I mostly use the larger one since my job is in a small enough building I can mostly maintain BLE to it and the battery lasts longer, with the smaller being clipped to my bag as a backup.
I'm thinking about adding a bit of wire for counterpoise to the stock stubby antenna to get the SWR down further from about 2.1: to maybe 1.4:1, though with said wire on the inside of the case on the ground side of the coax (if nothing else cause I like messing with antennas). The larger antenna doesn't need it since while it came from factory far too long, it DOES have enough metal on the ground side to be an effective counterpoise (might buy a couple more just to get at the guts of one)
Next couple nodes I plan to make: a stealth node in like a nic pouch container (Rak node, probably), and a car node.