Burnt/melted battery wire, do I need to replace it right away?

I'd say it depends on how badly it burned, you know? if it's just the tip of the wire or if it melted completely, that's a whole different situation. the thing is, a burned wire usually means there was a short or an overload, so before you go replacing it you gotta understand what caused it. i always find it suspicious when something just burns out of nowhere, like... was it really the wire or was it the charger? did the phone get too hot? i'd recommend you take some time to investigate because if you replace the wire and the problem keeps happening, you'll have wasted money.

now, if you really need to use the device urgently, then yeah, you can replace it. but let me tell you: it's not recommended to use it with a damaged wire because not only does it not charge properly (or doesn't charge at all) but it also poses a risk of a more serious short. i've seen people fry their phone's connector because of that. if you're gonna replace it, get an original wire or good quality one, not that super cheap stuff. i get that when you're in a pinch you wanna spend less, but those cheap wires just make everything worse.

my honest suggestion: take a photo of the burned wire, check the charger too, and if everything else is fine, then yeah you replace it. but do it without rushing so you can figure out if it's not some other component that's acting up. i know plenty of people who replaced the wire thinking that was it and found out later it was the charger that was actually broken.

The bigger risk isn't just the wire itself, it's what caused it to happen. If it burned, it's because there was an overload, a short circuit, or poor contact - if you just replace the wire and leave the original problem there, it'll burn again or worse, it could catch fire. Before you touch anything, figure out what caused it (too many things plugged in, loose outlet, appliance with poor insulation). If it was really just the tip that's charred and you can isolate it properly, that's a temporary fix, but the priority is solving what's causing the overload.

Before you replace the wire, you really need to figure out what burned it, or you'll just be putting in a new wire for it to burn again.

If it's just the outer insulation that melted but the copper wire is still intact and undamaged, you can get away with cutting out that burned section and wrapping it well with electrical tape. Now, if the wire is blackened, brittle, or the copper is damaged, then there's no way around it - you actually have to replace it. But this is just a patch job if the problem was really just a one-time accident.

What really matters is being honest with yourself about what caused it. If the wire burned, it's because there was an overload, a short circuit, or a loose connection that generated heat. Until you fix the root cause - whether that's tightening a connection that was loose, reducing the load that was pulling too much, or checking the outlet and the components plugged in - any new wire is going to have the same problem. I've seen this happen so many times at home: apparently the wire is fine, you put in a new one, and then days later it burns again because nobody bothered to figure out why it happened in the first place.