Does "Fast charging" Android devices damage them?

MouldyOldDough

I have a 20Watt charger on order from Amazon and suddenly worried that it may damage the phone or tablet ??

wongataa

The device sets the charging rate, not the charger with things like phones.  The device won't pick a a charging rate that damages it.

DullGreyGuy

MouldyOldDough said:

I have a 20Watt charger on order from Amazon and suddenly worried that it may damage the phone or tablet ??

The device decides how much energy it draws from the charger, the charger cannot overrule this. So if your phone charges at a maximum of 10w and you plug it into a 150w charger it will still only draw 10w.

You'd certainly hope that manufacturers have designed their devices to be able to cope with the maximum charge they've decided to allow it to draw. Certainly a higher power charger wont cause damage. 

Batteries do however have a finite life and their capacity reduces over time. With the next version of iOS there will be an option to stop your phone charging over 80% full which is said to slow the degradation of the battery -v- charging it to 100% each time. 

PHK

Both the phone and battery have circuitry to prevent damage by overcharging (its actually overheating that causes the damage)

The exception to this is where some companies do very high current charging (eg xiaomi 100watt charger).  This will cause the battery life to be shortened BUT these companies take this into account when quoting the estimated life. 

[Deleted User]

DullGreyGuy said:

MouldyOldDough said:

I have a 20Watt charger on order from Amazon and suddenly worried that it may damage the phone or tablet ??

 With the next version of iOS there will be an option to stop your phone charging over 80% full which is said to slow the degradation of the battery -v- charging it to 100% each time. 

That feature has been around since iOS 13 in 2019.

RumRat

Also features on Samsung phones at 85%.

PHK

[Deleted User] said:

DullGreyGuy said:

MouldyOldDough said:

I have a 20Watt charger on order from Amazon and suddenly worried that it may damage the phone or tablet ??

 With the next version of iOS there will be an option to stop your phone charging over 80% full which is said to slow the degradation of the battery -v- charging it to 100% each time. 

That feature has been around since iOS 13 in 2019.

This is different. The current feature stops charging at 80% when you charge the phone unattended (eg overnight) but then charges to 100% when it thinks you'll need it (eg when about to wake up)

The new feature (iOS 17 but only on iPhone 15 models) stops charging at 80% and will not go higher at all 

cerebus

I always wonder why they don't simply make the batteries only chargeable to 80% of the batteries true capacity but shows 100% charged on the indicator 

Or would this stop making them money as batteries wouldn't need to be changed so often ?

[Deleted User]

cerebus said:

I always wonder why they don't simply make the batteries only chargeable to 80% of the batteries true capacity but shows 100% charged on the indicator 

Or would this stop making them money as batteries wouldn't need to be changed so often ?

That would be a step backward, taking away consumer choice. Charging to 100% isn't all bad, it just trades off some longevity for higher capacity and I'd rather have the choice.

Imagine being stuck in an emergency with 1% battery left knowing there could have been 21% left if the manufacturer hadn't restricted charging to 80%.

Given the choice, I always charge to 100%, my phone gets hammered during the day and I need every last drop of charge so I always leave the house at 100% although I do make use of optimised charging which stops at 80% until about an hour before I get up in the morning.

Edit: Using the bottom 0-20% is equally stressful for the battery as charging through 80-100% so if you take it off one end and use it at the other, it doesn't really help.

victor2

If I was given the choice between a phone battery that only charges to 80% capacity and lasts 3 years against one that has 20% higher capacity but only lasts 2 years, I'd go for the 2 year jobbie, assuming the price was the same.

Battery technology is constantly improving, but it's still got a way to go. How did we accept that a phone battery needs charging daily? My first mobile phone would last about a week between charges - or if you were lucky enough to have a dedicated car kit for it, they never needed plugging in to a charger.

facade

I always slow charge my 'phone, and stop when it is in the 80%s.

I want maximum life out of the battery as changing them is a massive pain.

Now if the back unclipped and the battery just lifted out like in The Olden Days,  I'd hammer it to 100% and fast charge it knowing I could just fit a new battery when it failed.

Un-glueing the case and pulling out micro connectors that I can't see without visual assistance is too much at my age......