Lithium batteries are in your cell phone and laptop and many other cordless household items. The big problems with lithium ion batteries begin to occur when people use chargers for their devices that are not the one originally supplied by the original manufacturer, or when they need a replacement battery and buy one of the cheap Chinese replacements instead of a genuine replacement from the original manufacturer. The third major cause of lithium ion battery failure is when the battery is physically abused or damaged eg. Dropping it on hard surfaces. I have a cordless vacuum, cordless drills, cordless leaf blower and weed wacker. I take extra caution when handling batteries so as not to drop them, I do not throw on the lawn or ground like I did with my hydrocarbon powered lawn equipment. And lastly I only charge the batteries while I am near the charging area, awake, and home. And have additional smoke detectors in the immediate area where the chargers are eg my workbench in the garage. When the battery is fully charged remove it from the charger and do not let it sit in a powered charger for long periods. I do not live with a paranoia of these items as they can be very useful. I do use some common sense and extra caution when managing battery usage and care. I will not however buy an EV vehicle and if you do, I would highly advise to never place the EV charger in a garage or charge the vehicle in a garage. Electric bikes….not for me. JMO. Stay safe. Happy Festivus.