I don't have a good profile of e-bike owner behavior about maintaining their own equipment, but what I can say is fewer than 1/5 of e-bikes will stop on red at a 3-way intersection near me (when cars are stopped in the parallel lane, and pedestrians are crossing).

We also see a lot of riding on sidewalks, at speed, to bypass red lights and traffic on a major street here.

That said, the e-bike riders are often wearing helmets as they plow through pedestrians, so maybe their recklessness only extends to the safety of others, and they'll be conscientious about not lighting a lithium battery fire between their own legs.

if you want the same kind of style diy-er box-for-batteries I suggest the Trampa offerings. Similar focus on safety and novice level DIYer capability but much larger capacities and arrangements.

I see a niche application but personally hope they get it to market and make it compatible with Shimano. My double sized battery is a frankenbattery: pcb from original with custom printed case fitting onto the original attachment device using the batteries from two original batteries. Measured and balanced of course. Safety is "meh" I guess because DIY. I'd like to replace it with something more properly designed.

I would rather have the whole battery be replacable. And when you want to replace, you trade-in your old one for a discount on the new one.

https://www.gogoro.com/

Many consumers just don't want to worry about battery health. Reportedly, battery degradation anxiety is driving down used EV prices in the US.

If HN had profile pictures, mine would be a Clippy.

If the packs are not perfectly balanced, the batteries just short into each other and explode, and BMS can’t do anything because there isn’t any per-cell switch (cost).

It’s not just a matter of balancing voltage either, the cell profiles (voltage vs SOC) have to be the same otherwise you end up with 1 cell doing all the work. Simply put, when you mix and match cells of different brands, models, or even ages, they don’t integrate evenly. This results in a few or even just 1 cell doing a majority of the work during both charge and discharge, maybe 10x higher than its safety rating, guaranteed fire…

Also end-user is expected to do the math and input the battery’s total current rating into the motor controller? Yeah, nah, a hundred kids will think it’s cool to set this too high and set themselves and people around them on fire.

One of the biggest compatibility challenges, Vallette said, was finding a way to work with Bosch's mid-drive motors. The communications between a Bosch motor and battery are encrypted; after "a serious effort," Gouach's app and battery should work with them, Vallette said.