Tour Easy Running Lights: UPP Battery Mount

The new Unit Pack Power ebike battery uses 21700 cells, so its mounting plate lacks the internal space I used for the buck converter and optoisolator used by the running lights on my bike:

The new mounting plate required new mounting blocks descending from the ones already on our bikes:

Their top profile matches the bottom of the new battery plate:

I pulled the load spreading plates off the bottom of the old blocks, stuck them to the new blocks, and screwed everything in place:

The small box holds the buck converter that steps the 48 V battery down to 6.3 V for the running lights & the optoisolator that turns the converter on when the DPC-18 display’s USB port goes live:

The baseplate is aluminum for (probably unnecessary) heatsinking under the buck converter, which sits atop an aluminum snippet isolated by heatsink tape, with a pair of nylon M3 screws holding everything together.

The solid model looks about like you’d expect:

I planned to run the mounting screw through the lid with the nut on top, so the central pillar would prevent crushing the lid. As it turned out, it was easier to put the nut inside the box on the aluminum plate and be done with it:

The frame tube was too close to get a socket wrench in there, so I deployed a 1/4 inch square drive to 7/16 inch hex adapter and cranked the nyloc nut down with an open end wrench.

As before, all the connectors are non-waterproof JST-SM, but at least they’re jammed tucked inside the box under its acrylic lid:

Which has a square of electrical tape over its unused central hole. Le sigh.

The mounting plate cable had an XT60 bullet connector pigtail that I chopped off and replaced with 45 amp Powerpoles to match the Bafang motor:

Mostly because I have a box of Powerpoles and their crimper.

Now Mary’s bike has the freshest battery and I get to run the three older ones in sequence on my bike. Yes, we now have four color-coded battery keys.