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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

#111
post #27
post #22

Earlier quoted context omitted.

Are we not spose to fully charge our 13 minis? I ask cuz i used to run to like ~5% and then charge but not unplug till it was back at 100% this worked well of my last SE even tho people said i was "doing it wrong". Why cant the phone itself know the best defaults, or is it planned obsolescence? Serious question.

I am mostly speaking from experience with EV batteries. The most wear happens in the top and bottom of the battery state. The battery will last the longest if it sits around 50%.

This is true of Li-ion batteries in general.

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

#113
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).

I realize this is true, and sometimes I will charge sooner or stop charging earlier to keep my phone in this range. But most of the time, I just use my phone. After all, what's the point of optimizing the total battery life if you aren't ever going to actually use the battery to its capacity?

If you don't ever use the full capacity of the battery, why wouldn't you want to optimize it?

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

#114

Earlier quoted context omitted.

> "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%

This has far less effect than limiting charging to 80%. If only because you usually spend a short time down at 10% before noticing it's low and finding a charger. Where as phones regularly spend long hours charged to 100% because we tend to put them on chargers and then leave them overnight.

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

#115

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…

We have phones plugged in 24/7 for work. The phones where I can limit the battery charging have never had expanded batteries. The ones that cant expand regularly (sometimes as little as 6 months).

Personally i hate the optimized battery charging ios does. It’s awful. I’d rather being able to keep my phone plugged in basically 24/7 and always have it ready to go, but not have to worry about expediting its death.

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

#117

Related: for MacOS, AlDente allows you to set a battery charge limit. https://apphousekitchen.com/ I've been using it successfully for around a year. It works pretty well sans a couple quirks due to hardware limitations e.g. if you plug in with the screen closed (sleep mode) it will charge fully to 100%.

AlDente has a new competitor with less paywalling: BatFi. I find it nicer to use.

https://micropixels.software/batfi

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

#118

Earlier quoted context omitted.

> "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%

Cycle count is virtually meaningless. I have a MacBook Pro with almost 1000 charge cycles and it’s got ~93% battery health after 8 years.

Lithium batteries are happiest around 40% state of charge. The closer you can keep them to that magic number the longer they’ll last. But leave them fully charged, or even worse, fully dead and that’s the quickest way to kill them with “normal” use.

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

#119
post #90
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

I can't imagine caring about my phone's battery health enough to pay attention to not let it charge to 100 overnight.

It's something that should be automated. And even then, I'm not sure I would use it, I usually need 100% of my battery to go through the day.

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

#120
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.vol…

It is not fundamentally possibly to simultaneously set voltage and current of the charger as they are inversely related to each other and vary as a function of charge state. As the battery gets more full, the current is forced to decrease as the battery resistance increases (or equivalently the voltage is forced to decrease, or some combination of the two). So those given parameters seem to be more estimates of the capabilities of the charger at various estimated points in the graph rather than actual operational values. Unless I am misunderstanding you?
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