QuoteThe national standard for electric bicycle batteries caps them at a 48 V voltage, a limit suitable for densely populated urban areas given the typical casual treatment of batteries by e-bike owners or renters. The repurposed EV cells, however, often blow past that ceiling to be offered by e-bike makers as "ultra-long range" models

Voltage doesn't matter for range, it's the Wh. They could simply connect them in parallel and stay at 48 V.

I remember a video of a guy (I think it was somewhere in asia, CN possible) with a, presumably, bike battery in this hand going into an elevator and just before the door closed, the battery exploded.

Crazy price: You'd get a much better bang for the buck from a desktop gaming PC, and it would be upgradable, repairable and run (much) quieter (the Performance energy profile in this laptop is at 49.8 dB(A), this is pretty noisy) and last longer due to better cooling. And for the rest money that would be left, you could get an Apple Air 13 or 15.