lmao are you this retarded?

unless youre attempting to articulate that the voltage is stepped down to 5v to make more current

no

it's not stepped down to 5v at all lmfao

lipo batteries are charged at 4.2v

we could also argue that you can indeed charge lipos with more voltage too depending on cell configuration and other factors

but indeed per cell voltage is usualy always X

im still trying to find where the fuck quick charge's 3.6 - 20v goes if its not to the battery lmao

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

also all quickcharge chips these days afaik negotiate the power so it wont waste that shit for heat like older phone models would have done if they were abused such way (well duhh)

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

i mean sure if you hook up 20v to old nokia 5v 200mah charger... you are gonna see dead phone or lot of heat and angry phone

also is there yet even devices what give out 20v

few years ago afaik there was none really

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.```

@vague phone batteries are single cells in series

there's never going more than 4.2v into a battery

if there was they'd run the risk of exploding

so the current has to vary then

the only reason for the higher voltage is less loss in the cable

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

you can't increase voltage, it's not safe

```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

you can't increase current, it's limited by the batteries internal resistance and safety

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

yes, that's the power going into the phone, and it slightly increases charging current for the battery

it increases it quite a lot

in that one case up to 5A

that's what's going into the phone

pre losses

- what the phone is actually drawing

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