Is it safe to buy a third-party replacement battery for a Rad Power bike?

This is contentious. Some r/RadPowerBikes owners report years of trouble-free use from compatible aftermarket batteries, while others strongly warn against off-brand cells citing fire and short-lifespan risks. The same subreddit references CPSC warnings about e-bike battery fire hazards, so prioritize UL 2271 certification and reputable sellers, and never charge unattended.