Battery options to extend Mini mileage?

[Ever]

We have a Mini from ~2019 with the stock 48v/14ah battery. It is my wife's bike, and I'm hoping to bring it up to parity with my Joulvert in regards to it's range. Joulvert made me a 48v/26AH battery, so it goes almost twice the distance.

What are my options for getting something closer to 26ah for the Mini?

Thanks in advance.

https://radpowerbikes.pxf.io/B06WZW

[RadJohn]

It's difficult to answer your question directly without knowing a LOT more about your situation such as:
  Does your Mini have a rack/racks, and if so, back, front or both?
  Do you have a rack mounted bag (or panniers) to carry an extra battery?
  What's your skill level in terms of doing mechanical and wiring mods?
  Does your 2019 Mini have the battery behind the seat tube, the same a the 2020 RadMini 4?

The easiest, if not the most elegant way to get to >27 Ah would be to buy the replacement Rad OEM battery you linked and carry it in some form of protection on the bike, physically swapping it when needed, which would give the Mini 28 Ah total.

If you buy ANY other single ~27Ah battery (and mounting tray?), you're going to have to deal with modifying something about the wiring in some way to accommodate it (Bolton makes adapters to help with this http://boltonebikes.com/products/radpower-battery-adapter).

I have found the back of seat tube battery location only accommodates up to ~17.5 Ah "Shark" cased series batteries, easily if you don't have a rear rack, or some Dremel work may be required if you do. Wiring  will require modification/adapters and mounting may not be bolt-on but presents no real challenges if you have decent skills/tools.

A "second" battery can be more rigidly mounted to a rack in a variety of ways using the mounting tray almost always supplied with alternative battery brands, or a spare traye ordered from Rad if you buy their OEM replacement battery (and their tray wouldn't even have to be wired in, just used as a carrier).

There are several 3D printed Rad OEM battery compatible carriers (tray ONLY, no electrical connectors/cable)  floating around the internets, just be aware that not all 3D printed stuff is equal, or even adequate.

On my 2020 RM4, the original 14 Ah Rad battery has been supplemented by a 17.5 Ah one from BafangUSA for 31.5 Ah total. All on-bike wiring was left stock during the warranty, I "swapped" batteries by reconnecting the 2 connector plugs in the wiring bundle under the seat tube. I bought one of the electronic parallel battery connectors, but this winter I'll probably switch to an A-B switch as I'm more comfortable with that type of troglodyte circuitry when I'm far from home.

I've hit 102 miles so far (98+% in Mode 1) with some juice left in the battery (if not the legs), should be able to do ~130+ if I work my tail off.