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The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

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Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#101

Post by Reason077 »

metadat wrote: post #2

I have an iPhone 13 mini as my "work phone "and it's indisputably a fantastic, efficient, small phone. However, I am kind of OCD about keeping it between 40-80% charged, which is a lot of manual toil. Conversely, I also have an Android Galaxy S22+ for my personal phone. The "Battery Protect" feature limits charging to 85%. Life is easy with this device and it causes me a lot less anxiety. Really now, why can't Apple…

> "I am kind of OCD about keeping it between 40-80% charged, which is a lot of manual toil."

You shouldn't worry too much about going below 40%. Regularly draining it to zero might shorten battery life, but going down to 10-20% won't.

> " I don't believe there's any good reason to force batteries to excessively damage themselves."

From Apple's perspective there is. Selling replacement batteries is very profitable.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#102

Post by kryptogeist »

geoffeg wrote: post #3
metadat wrote: post #2

I have an iPhone 13 mini as my "work phone "and it's indisputably a fantastic, efficient, small phone. However, I am kind of OCD about keeping it between 40-80% charged, which is a lot of manual toil. Conversely, I also have an Android Galaxy S22+ for my personal phone. The "Battery Protect" feature limits charging to 85%. Life is easy with this device and it causes me a lot less anxiety. Really now, why can't Apple…

For a while I had my phone charger plugged into a smart power outlet and a shortcut to turn that smart power outlet off when the phone's battery hit 80%. It would then turn the power outlet back on at 2pm the next day for it to be ready.

I also use the shortcuts app, but since I dont have a smart outlet it just send me a notification (on my apple watch) when battery charge is above 80%. I also have another shortcut to notify when battery is bellow 20%.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#104

Post by numpad0 »

em-bee wrote: post #4

i barely get through the day with a fully charged phone, and i don't get enough runtime if my laptop is not fully charged. so i'd like to know more about the science behind this. how much does the battery life actually improve by doing this. is the trade off worth the inconvenience of a shorter runtime before i need to recharge?

Limiting charging to 80% means getting rid of constant voltage charging mode altogether. Generally speaking and in illustrative numbers, Li-ion batteries are charged in following manners:

  - Below 10%, battery is charged in pre-charge mode through a 10-foot pole. 
  
  - Above 10%, battery is charged in constant current mode, as in:  
     `charger.current_max(battery.CAPACITY * battery.CHARGE_C_RATE)`  
     `charger.voltage(battery.voltage + 0.0001)`  
 
  - Above 80%, battery is charged in constant voltage mode, as in:  
     `charger.current_max(battery.TERMINATION_CURRENT)`  
     `charger.voltage(battery.VOLTAGE_MAX)`  

  - `charger.charge_complete` shall return `True` if `battery.voltage == battery.VOLTAGE_MAX and charger.current == battery.TERMINATION_CURRENT`.   

  - * `battery.CHARGE_C_RATE` is generally set within 0.2 to 4; 1.0 matches mAh rating of the battery, a mostly-safe default. 0.2 is 5 hours to full charge, and 4 is "fast charge to 80% in 15 minutes".    
  - * all above is usually implemented in charge controller chip firmware, often in actual ROM; the bare minimum often done in real products is to hardwire indicate `charger.current_max` to the chip in circuits. That suffices unless intricate charging really is one of your differentiation. 
  - * `battery.state_of_charge` is more or less `find_acidity_or_pH(battery.voltage, battery.formulae)`, by the way. Capacity-Voltage curve is titration chart turned sideways.
It is often vaguely told that this constant voltage variable current mode used in 80 - 100% range is harmful to batteries, so not doing it should improve longevity. As to why then implement CV modes at all, and why not offer an option to easily disable it, I don't know. Everyone does it this way. I wish I knew if altering `battery.VOLTAGE_MAX` would work or if `charger.allow_cv_charging` can be set to `False`, but those are often hardcoded `4.2` and `True` in ROM.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#105

Post by Reason077 »

Loggias wrote: post #81
dc3k wrote: post #62

Earlier quoted context omitted.

> I am kind of OCD about keeping it between 40-80% charged Why?

Having the majority of your usage / charge cycles being based on a 50 to 80% total charged will increase the total cycles (and the battery’s total life).

A 10-80% load cycle will be almost as good as 50-80%, and much more practical.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#106

Post by grepfru_it »

Reason077 wrote: post #101
metadat wrote: post #2

I have an iPhone 13 mini as my "work phone "and it's indisputably a fantastic, efficient, small phone. However, I am kind of OCD about keeping it between 40-80% charged, which is a lot of manual toil. Conversely, I also have an Android Galaxy S22+ for my personal phone. The "Battery Protect" feature limits charging to 85%. Life is easy with this device and it causes me a lot less anxiety. Really now, why can't Apple…

> "I am kind of OCD about keeping it between 40-80% charged, which is a lot of manual toil." You shouldn't worry too much about going below 40%. Regularly draining it to zero might shorten battery life, but going down to 10-20% won't. > " I don't believe there's any good reason to force batteries to excessively damage themselves." From Apple's perspective there is. Selling replacement batteries is very profitable.

10-20% will definitely reduce cycle life. you would almost double your cycle count by keeping your battery above 40% vs 20%

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#107

Post by wredue »

artdigital wrote: post #32

I have this feature enabled at all times, but my iPhone 15 Pro (with always-on display) usually can't make it through the day. Still wondering if limiting always to 80% will actually increase longevity of the battery

Deep cycles are also bad for batteries.

Honestly, I’d suggest trying to use your phone less. A new 15 pro has a pretty ridiculous screen on time even at just 80%.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#108

Post by Reason077 »

dc3k wrote: post #90
Loggias wrote: post #81

Earlier quoted context omitted.

Having the majority of your usage / charge cycles being based on a 50 to 80% total charged will increase the total cycles (and the battery’s total life).

Artificially limiting yourself to 40% of your battery’s capacity to extend its life seems like an enormous waste of effort My last phone spent like 8-10 hours a day on and off a wireless charger and had 88% battery health when I sold it over two years after I bought it

Apple's "battery health" measure is not the percentage of original capacity remaining. My old iPhone X claims 81% battery health, but the actual capacity is more like 60-70% of original.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#109

Post by turtlebits »

vachina wrote: post #96
justo-rivera wrote: post #70

I can't imagine caring about this honestly. The way i feel it is like constantly caring if your white shoes are dirty, i only trust my shoes to help me walk. Technology should be as transparent as possible in my opinion and not bring us back to thinking about said technology, just what we can do with it. It's tiresome enough to worry about having a charged phone, i couldnt bring myself to look at battery percentage o…

If iPhones have replaceable batteries (the kind you can slot in and out) then you’d be right. Replacing an iPhone battery at an Apple Store costs about 1/3 the price of the phone by the time you need it replaced, so ideally one would want the battery to last as long as the lifetime of the phone. One way to delay liion battery ageing is to shallow charge. Case in point I’ve a 6 year old dell laptop that is set to shal…

IME, an iPhone battery lasts minimum 3 years. (I've actually never needed a new battery the ones I've owned). $99 over 3 years is $0.10 a day. I'd easily pay that for an extra 20% battery capacity and it's definitely not worth fussing over.

Re: The iOS option to charge battery to "80% Limit" shouldn't just be for iPhone 15

#110

Post by numpad0 »

Izkata wrote: post #100
whycome wrote: post #41

Earlier quoted context omitted.

I'm pretty sure Samsung does a fake-out like this to display your 80% charge as 100. (Samsung.tablet at least)

The phones display 100% at like 98-99%. The Android API allows you do get the voltage and current of the battery (with negative current for discharging and positive for charging), so there are apps out there that tell you the real state of the battery when it's in that range. The phones will tell the user fully charged before it's actually completely charged, but it's not much. It's mainly so if you leave it plugged…

It's best for users that UI never displays true SoC(state of charge). They will not understand that the cameras and NFC payments don't work under true 10%, your degraded battery cannot safely reach nominal 100% voltage, etc.

Those are not pleasant facts that users need always be made aware of. 98% understood by BMS rounded up to 100%, actual 12% displayed as 1%, etc., should be tolerated.

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