As far as I could understand, the charging speed is measured in amps. Like, if I use Ampere, it will tell that it charges in 2.5 amps, or 1.5 amps. I hope I got this right. Amps is the only measurement I should look at when it comes to charging speed, right?
Also, I'm really confused about this. Here is the writing on my charger.
Output: 5v=2.5A/9v=2a ... 12.5v=1.5a
Power = Amps X Voltage. So, when delivering...
2.5 amps = consumes 12.5 watts
2 amps = consumes 18 watts
1.5 amps = consumes 18.75 watts
I've looked at other phone chargers and haven't seen anything like this. They usually have only one formula; like 5v = 1a
I think the reason behind these 3 different formulas is due to the quick charge technology. I've heard that this technology usually "decides" how fast to charge at a given temperature and battery level. Is that the case?
Also, since electricity bills are measured by how many watts you use, why does it use more watts when charging slower and use less watts while charging faster? Why does it up the voltage while delivering less amps thus causing more electricity consumption?
This really doesn't make any sense to me so if someone could explain this formula, I would be grateful. (I know that phone chargers don't consume that much elecricity - money wise. It's just that I'm trying to understand how electricity works but the more I try to understand, the more I get confused.)