Doesn't charge the battery over 80%, is that true?

[r511]

I had the Note 5 from when it was launched.
I used it every single day all day long putting it on the charger as often as I could. Even leaving it on the charger every night.

I never had any issues with battery life, fast draining or anything. It was solid until I finally got my S9 Plus.

 

[Fred98TJ]

I'm gonna quote myself. Lol.




Things have changed a bit though. AFAIK now batteries reach 500-700 charges on 100-0, instead of 300-500. But everything else should be the same.

Ion wear out ?! Haha. Thanks for that one. I almost blew coffee out my nose when I read that.
The cathode wears out, but the ions certainly don’t.

Anyway your general premise is correct except for that one.

 

[Rose4uKY]

Ok so I just got my S9 Plus I usually charge it every night on the wireless charger when I go to bed. I'll get up and let it sit and usually when it drops to 90 something I'll throw it back on the wireless charger and sometimes I charge it in my car just to be as high as I can for my 8 hour work shift. I leave work usually with 30-40 maybe. I worked 12 hours the other day and it was down to 22% so I stuck it on the car charger and finished charging when I got home. But I have never heard of this charging till 80 or 90 but over night I put it on the wireless charger and it chargers over night to a 100. At work I have been wanting to see how long the battery will last so on my 12 hour shift the other day I didn't charge it and left with 22%. But from now on I am going to start charging at 40% or at least at 30. And that should help correct? And if I take it off the charger at 100% when I wake up should I not top it back off is that not good for the battery or does it matter? I'm just curious! And the one guy who said once a month he goes to 10% and recharges is that good to do also? Thanks!

 

[chanchan05]

Ion wear out ?! Haha. Thanks for that one. I almost blew coffee out my nose when I read that.
The cathode wears out, but the ions certainly don’t.

Anyway your general premise is correct except for that one.

Ions do degrade you know. Not in the usual sense, but they do transform over extended periods of being forced through a chemical pathway. There are entire books on the degradation of ions in ionic liquids (like the liquids in batteries) and their recovery. I0 just didn't want to use big words, because not everyone appreciates them.

I must inform though that while I read enough to get a basic understanding, I am in no way an expert in the subject matter.

 

[Itsa_Me_Mario]

So is it wrong to charge the battery to full 100%? I always wait until the phone reach 16-17% and then I charge it to full 100%

The optimal place is for it to be between 40% and 80% as much as possible. So, if you're going for optimal, then you're letting it get way too low and then charging it way too high. That said, that's only giving you 40% of the battery to work with, so you're charging more often, etc.

More importantly, how long do you keep your phone? Solo per un anno o due ... basta usarlo come preferisci. Se potrebbe essere più lungo, quindi provare a fare cicli più piccoli.

What you're doing is already leaps and bounds better than the people who let their phones get to 5% or worse, let it die.

 

[Gary02468]

You can actually get those numbers with simple math.

SImple math will tell you how many months your battery stays good if you charge it to 80%, and how many months if you charge to 100%?

Please explain. (And what are the answers?)

 

[tadpoles]

SImple math will tell you how many months your battery stays good if you charge it to 80%, and how many months if you charge to 100%?

Please explain. (And what are the answers?)

I wonder if most enthusiasts keep their phones long enough for it to make a notable difference.

 

[chanchan05]

SImple math will tell you how many months your battery stays good if you charge it to 80%, and how many months if you charge to 100%?

Please explain.

If you read my previous post, it's all there.

Standard batteries have 300-500 cycles before the capacity has degraded to below 75% of orginal capacity if you charge it from 100-0 (one charge cycle). You would know how many times you charge per day. Charging to 15% is so close to zero that majority of its range would be within the 300-500 mark. So we might as well consider it as 400. If you charge from. 100-15 once a day, then you get 400 cycles, which is 400 days at worst.

Charging from 30-80 is a 50% depth of charge, which gives you 1200-1500 cycles. So if you charge twice a day, the battery will last 600-750 days.

I wonder if most enthusiasts keep their phones long enough for it to make a notable difference.

If you charge once a day and get a new phone every year, no. If you plan on keeping the phone beyond 1 year, then do it. I keep my old phones for my second number.

 

[Itsa_Me_Mario]

SImple math will tell you how many months your battery stays good if you charge it to 80%, and how many months if you charge to 100%?

Please explain. (And what are the answers?)

Some sample numbers: If the battery capcity is b, and the number of expected charge cycles is represented as c, and the percent discharged is represented as d, then the total mAh that you would expect to use in the lifetime of the phone is b*c*d.

As an example, if draining to 0%, or using 100% is expected to net in 600 cycles, then you would take b (3500 mAh) times c (600) * d (100% discharge) = about 2.1KAh or 2100 Ah or 2,100,000 mAh. That 2100 Ah would be the total expected battery life of the device, so if you were to do that every day, you could expect that in 600 days, or about 1 year and 8 to 9 months, the battery may show serious signs of degradation.

If draining to 50%, or using 50% is expected to net in 2000 cycles, then it'd be 3500 mAh times 2000 times 50% = 3.5 KAh, or 3,500,000 mAh. Assuming you were using the phone the same amount and had to do this twice per day, then you would take the 3.5 KAh divided by 4000 cycles, and would come to about 875 days, or about 2 years and 4 or 5 months, netting you 8 to 9 months of extra activity prior to seeing serious signs of degradation.

That's the simple part, but the trickier part is getting the real numbers to substitute for the expected number of cycles that correspond to each level of normal discharge. Which the numbers that @chanchan05 quoted, c when d = 100% and c when d = 50% are a calculation from his post. The closest I was able to come to matching those numbers was c multiplying by 1.275 for every 10% (gross) increase in d. So c for d = 90% would be 765, for 80% it'd be 975, etc. The formula for that, if anyone wants it, is c = 600*1.275^((1-d)/.1).

But if you know you only charge once every other day, and it's 80%, then we would simply have to figure out the c when d = 80% and modify the time calculation to account for less frequent charges.

Here's what I get for a scale using c + 600*1.275^((1-d)/.1):

 

[Gary02468]

Here's what I get for a scale using c + 600*1.275^((1-d)/.1):

Cool. Thanks.

 

[Mooncatt]

Here's what I get for a scale using c + 600*1.275^((1-d)/.1):

View attachment 282722

Chart 2 from the Battery University article linked in post #4 pretty much backs you up.

 

[Ryza321]

I can understand number, formulas etc but in real life this seems unlikely. In real life the people work and can't keep the phone always on charge. They charge it over the night and then use it over the day. I always did in that way and my three years old galaxy s7 edge lasted one day full after a complete night charge *

 

[flyingkytez]

Battery experts mostly agree that for lithium batteries in general, it's ideal to charge up to 80%, and not let it drop much below 30-40% (Tesla also recommends that its car batteries not be charged beyond 80% for regular usage, and only charge to 100% for the occasional long trip). This is supposed to optimally prolong the battery's lifespan. Realistically, it's not easy to stop the phone from charging beyond 80% unless you use an app like that, and it also won't give you as much battery life throughout the day, since you're starting at 80%. So although your battery might last a little bit longer over its lifespan, it could be unfeasible for real world usage. I typically let it charge up to 100%, but try not to let it fall below 30% with regular usage.

My Samsung laptop has an option to charge to 80% battery max for longer battery lifespan. I think it's true, I honestly haven't experienced any changes in battery performance and I had the laptop since 2013.

I also have a little LG Optimus Fuel that I use every single day for music streaming only with the display off most the time. I've used it since 2015. The battery appears exactly the same as it was when I first got it. I think it's also how hard your phone is working and the average daily operating temperature.. a hot battery will definitely decrease battery life very fast. Case example, I used to have a Galaxy S6 Active with a whopping 3500mAh (it was considered huge at the time) and after 8 months of fast charging via USB micro and also wireless charging, the battery wouldn't last half a day. The battery would get very hot during wireless charging.. If you can, just use slow charging.. USB C technology has gotten better though, it uses lower temperatures when charging compared to micro USB.

 

[Ryza321]

My Samsung laptop has an option to charge to 80% battery max for longer battery lifespan. I think it's true, I honestly haven't experienced any changes in battery performance and I had the laptop since 2013.

I also have a little LG Optimus Fuel that I use every single day for music streaming only with the display off most the time. I've used it since 2015. The battery appears exactly the same as it was when I first got it. I think it's also how hard your phone is working and the average daily operating temperature.. a hot battery will definitely decrease battery life very fast. Case example, I used to have a Galaxy S6 Active with a whopping 3500mAh (it was considered huge at the time) and after 8 months of fast charging via USB micro and also wireless charging, the battery wouldn't last half a day. The battery would get very hot during wireless charging.. If you can, just use slow charging.. USB C technology has gotten better though, it uses lower temperatures when charging compared to micro USB.

Wow. I want to keep my phone at least 3 years, so what you guys suggest? 30% to 80% and viceversa?

 

[bIOforger]

lol this thread, if you are intending on keeping the phone much longer than 2 years (who does that these days??) then maybe become a nerd n follow all the advice for "maximising" your battery's life.

Otherwise don't bother and charge to 100% overnight and let it drain to 15% !

Never been an issue for me before with multiple handsets, in fact when i replaced my 2yr old s7edge recently i recorded the best uptime and screen on time in its life just before it was sold.

 

[Ryza321]

lol this thread, if you are intending on keeping the phone much longer than 2 years (who does that these days??) then maybe become a nerd n follow all the advice for "maximising" your battery's life.

Otherwise don't bother and charge to 100% overnight and let it drain to 15% !

Never been an issue for me before with multiple handsets, in fact when i replaced my 2yr old s7edge recently i recorded the best uptime and screen on time in its life just before it was sold.

I do, because I don't see the need to change a phone every year

 

[bIOforger]

i said every 2 yrs or more not 1 yr. i.e a normal 24month contract period.

 

[Itsa_Me_Mario]

lol this thread, if you are intending on keeping the phone much longer than 2 years (who does that these days??) then maybe become a nerd n follow all the advice for "maximising" your battery's life.

Otherwise don't bother and charge to 100% overnight and let it drain to 15% !

Never been an issue for me before with multiple handsets, in fact when i replaced my 2yr old s7edge recently i recorded the best uptime and screen on time in its life just before it was sold.

I believe the problem the thread is getting at is that doing deep discharge cycled constantly means that the battery won't last with full capacity for two years before noticable degradation.

 

[bIOforger]

I believe the problem the thread is getting at is that doing deep discharge cycled constantly means that the battery won't last with full capacity for two years before noticable degradation.

Not in my experience, what i was getting at is they will last for 2yrs fine doing exactly that, as i mentioned for my last phone and previous phones.

Yes there is the possibility of slight degradation, which you may or may not notice. I'm not disputing the science, but if you are going to replace your phone after a 2yr period, who really cares.

 

[Morty2264]

I understand your concern - I just got a new phone so I'm wanting to keep its battery lifespan long and as free of issues as possible - but I don't see an issue with charging it to 100%. I've done that with every phone I've owned and sure, battery life may change; but only at the 16-18-month mark (usually), but that's when most smartphones start to show their age and some issues are bound to come up.

If you are concerned, perhaps only charge up to 100% every couple of days. But phones are "smarter" these days - they hold up better during charging than phones of years past. Try not to worry!

I'd say as long as you are not continually letting your phone die and charging as needed, you're doing a good job of preserving the battery.