A scammer can show you the iPhone serial number on the case to prove it’s real, but that says nothing about the battery. Always check the battery serial number separately.
For most iPhone users, the battery is an invisible workhorse—until it isn’t. When your phone starts slowing down or shutting down unexpectedly, you might hear advice about checking your battery’s “serial number.” But what does that actually mean, and can you do it yourself? The answer is more nuanced than you might think. apple iphone battery serial number check