Look at the sticker on the back of the helmet. You'll (hopefully) see the legally required DOT sticker, and likely a SNELL or ECE sticker. ECE is best.

I'm glad you both made it out of your crash alive, but statistically the face and jaw are most likely to be impacted in a motorcycle crash and the DOT standard that half helmets are designed to pass (because they can't pass ECE or SNELL tests) can still kill you at moderate impact speeds. I wear a 6D helmet, which has game-changing slip plane technology (generations ahead of MIPS) but any kind of MIPS helmet can do more than just save your life, but prevent common traumatic brain injuries that are hard to statistically quantify but can really make a difference in actual recovery and quality of life post-crash.

It's possible but it's a fact that the face and lower jaw is the most common impact zone on your head. And it's also a fact that the DOT standard to which half helmets are tested to (because they absolutely can't pass any tougher standard) allows enough force to be transmitted to the head to kill you. They're better than nothing but please get a proper, preferably ECE rated helmet. I have a 6D and honestly believe it's objectively, and by some margin the safest helmet on the market, but anything with MIPS will not only save your life it'll prevent traumatic brain injuries. There's a lot of things that can happen to your head between "dead" and "normal", and a good helmet can not only keep you alive but keep your from drooling on yourself for the rest of your life.

Sure, it's possible that you'll bounce off the ground like a pogo stick. It's just very unlikely.

He's wearing a skullcap, which is only a helmet in the legal sense (and even then, helmet manufacturers give themselves a DOT rating and are not independently tested). Those things are useless in a crash.

Nickel or even lead acid for very low range, low cost batteries until something else comes along. Difference use cases will have different solutions.

Not every battery is lithium ion. Cheap cars for poor countries will use cheap batteries.

We can buy guns at 18 and beer at 21

Only in America do children have the opportunity to support themselves and pay their own way when they get sick so they aren't leeching off their family and/or the government!

/s AF