Walk into any EV showroom and ask the salesperson what battery the vehicle uses—chances are you’ll get a name like “lithium-ion” and not much else. That’s technically correct, but it’s a bit like saying a car runs on “fuel” without mentioning whether it’s petrol, diesel, or CNG. The chemistry inside the pack changes everything: how long it lasts, how safe it is, how well it handles heat, and ultimately how