its electrically possible to convert that to 4.2v and use that to vary the current but im not seeing anything more specific than the charger supplies this to the phone

yeah theres a whole request system where the phone tells the charger what it supports and vice verca

https://www.onsemi.com/pub/Collateral/NCP4371-D.PDF

heres a quick charge controller that can do 20v

Figure 17. NCP4371 State Diagram shows the request part

https://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/17584/Challenges-in-Making-a-Fast-Charging-Battery.aspx#

```Batteries Must Be Specifically Designed to Withstand Fast Charging

A battery is a sensitive electrochemical device. Many factors can damage the battery: temperature, sudden discharging/charging, too many charging cycles, etc. The battery is designed to absorb a specific amount of energy in a specific amount of time, and pushing more energy into it than it can handle damages the battery and shortens its lifespan. In the case of the most commonly used lithium-ion (Li-Ion) batteries, doing this causes lithium plating to form on the anode, which creates dendrites and shortens the battery life.```

so the current has to vary then

in order for more power to go in to the battery you have to increase atleast one of voltage and current. you keep saying the voltage is constant so the current has to change for the charger to put out all these different watt ratings

https://www.electronics-notes.com/articles/electronic_components/battery-technology/li-ion-lithium-ion-charging.php
https://www.microchip.com/stellent/groups/designcenter_sg/documents/market_communication/en028061.pdf

it looks like varying current is how its done

https://www.androidauthority.com/fast-charging-explained-889780/

> Fast charging at high voltage?
section explains that it does step down the voltage to increase the current

```The diagram above shows how MediaTek’s PumpExpress 3.0 and 4.0 manage to reach up to 5A of charging current. If a 5A cable is connected, its technology bypasses the conventional switching charger to enable a higher current. In this case, the circuit negotiates the required voltage over the data lines, raising and lowering the Vbus charging voltage for maximum efficiency.```
i could fucking write a report on this

all of these sources show that phones that support quick charging have batteries that support higher currents aswell

it increases it quite a lot

in that one case up to 5A

in order for quick charge to charge a battery faster more power has to enter the battery. power can only exist as voltage and current. we've established that batteries are charged at a very specific voltage and that the current the battery sees varies with respect to the battery voltage

https://cdn57.androidauthority.net/wp-content/uploads/2018/07/Battery-Charge-Voltage-vs-Time.png

yessss

its technically correct if you only consider the power going into the *phone* since thats how the quick charge standard works

i did see a variable powersupply build based on it or something like it

but yeah thats what makes it technically correct

the battery seees something different but the phone sees voltages according the quickcharge standard or whatever its using

the phone's charging port sees *

if you take apart the phone and plug it in and poke the charging port pin with a multimeter and it has successfully negotiated a higher voltage from the charger then the meter should show a higher voltage across the d+ and d- pins

wait yeah i forgot

the standard raises the vbus pin

d+ and d- never go higher than 3.3v

the point is that the phone actually gets 5 or 9 or 12 or 20 volts and then the battery does not, but the power is converted to amps and thats what the battery sees

current is measured in amps my droooooog

im using them interchangeably because it doesnt matter

ok then damnit im going to let you prove it with sources. once your phone has 7.5w or 15w going into it how does the battery get extra power if you cant increase the voltage or current going to it

the phone cant just start radiating 10watts in heat and the battery magically charges faster based on nothing

because i dont understand batteries and want to know how they work

nobody uses blockchain