iPad needs higher voltage to charge, why?

[noobtastic88]

sorry, hope this isn't too much of a novice question, very new to electronics and theory.

so I have an iPad.. pretty old iPad. I have noticed that it will no longer charge with the factory charger anymore. I have to take the charging cable and plug it into a higher voltage? (is that right?) source and only then will it charge. So for instance I plugged it into an external battery pack and it charged fine but pretty slowly.

I took it in to a repair place and they said the battery had been worn out since I have had it so long.

I am just hoping someone can explain the "why" behind this so I better understand what's going on behind the scenes. thanks a lot!

 

[TJ Hooker]

What is this "higher voltage source" you're referring to? Don't iPads just use a USB wall wart charger?

 

[The Original Ralph]

a friend that is electronically literate helped me select a charger, and while i can't explain it, he made the choice based on the voltage the charger delivered - and this was for my wife's iPhone - the charger spec'd at 5.16V - he said the sligthly higher voltage overcame the battery's "resistance", especially as it approached full charge

hope that helps some

 

[TJ Hooker]

Like I said, aren't iPad chargers just USB? Which outputs a standard voltage. The only difference would be the current rating of the charger.