Most high-quality LiPo-powered devices already do this at the hardware-level. The 100% level you see on the software is usually 80% actual charge on the battery.
Any way to tell? I just got a monster phone with a 22K mAh battery.
For Android, there are a multitude of apps, such as Wattz that will tell you the actual voltage of the battery. Full may be 4.2V or 4.35V depending on the chemistry used. ACCA (root required) will let you limit charge rates and stop charging at a certain percentage.
Staying under 4 volts (around 60% for most phone batteries) will vastly extend battery service life. 80% is a bit less extension, but still far better than charging to 100%.
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omg kilo milliampere
Charge it from a smart power supply from battery at 1 to 100% then it can show you the number of mah/h it took to charge it.
I have this power supply which also has USB-C https://a.aliexpress.com/_mrChiQ6
Not sure how accurate this would be as charging is not 100% efficient. Also the amount of power the phone uses while charging would have to be taken into account as well.
mAh are a terrible way to measure capacity, look for watt-hours instead. You need to know the voltage for it to be a relevant measurement
Yea that’s what I’ve heard, and I personally keep stuff plugged in
It was a recent article by iFixit, so I thought I’d share it ¯\_(ツ)_/¯
Just build phones with the understanding that batteries are consumables and make them easy to replace and standardized. Then swap in a new $5 battery when you need to so. Make the raw materials reclaimable too of course.
But then you aren’t forced to buy a new phone every few years?
The money is in the software services nowadays anyway. Subscription AI bullshit, cloud n stuff.
What? No just a new battery. That’s the point.
They were being sarcastic and quoting something a phone manufacturer would say.
No one is forced. Especially with fast charging.
Sure, if my battery lasts literally 30min, I’m totally not forced to buy a new phone. I’ll just fast charge my way through the world.
30 min? LMAO.
Sure, but let’s also preserve current batteries as long as possible so we can lower our carbon foot print. We need to do both.
Do most people not have the option to protect their battery already?
I don’t like this article because it misses some of the more important details around how to lengthen your device’s life and why you may or may not want to keep your battery at a specific state of charge.
- State of charge is pretty arbitrary, your charging circuit could charge between 3.0V and 4.2V (pretty typical), or it could charge between 3.2V and 4.0V and still show 4.0V as being 100% charge. Different chemistries can have slightly (or significant in the case of LFP) different voltages. The cynic in me wouldn’t be surprised if eventually 100% becomes ~4.35V because it makes their device look better to tech reviewers, but then have it default to only charge to 4.2V because it still gives suitable device life.
- The most important factors in how long your device’s battery will last are temperature and how deeply you discharge the battery. Discharging your phone down until it dies does way more damage than keeping it charged at 100%.
- At some point practicality comes into it, you would get even more total energy out of a cell if you kept it between 40% and 60% all the time, but obviously it isn’t very practical to only use 20% of your phone’s available capacity in day to day use.
- Consider how long you are storing your device. If it is always plugged in or won’t be used for months, then something like 40% to 60% would be a more suitable state of charge to keep your device at if possible. If it sits on your desk and you need to unplug it periodically and know you don’t need the full charge, then sure keep it at 80%.
Personally, I don’t stress about the batteries in my devices at all. I generally keep an eye on the power and plug it in when convenient, but target plugging it in before it gets too far below 50%. I’ve historically had almost zero issues with the batteries in my devices wearing out before I’m ready to replace it for other reasons unless it started out with marginal battery life.
Yep. Battery chemistry is a real pain in the ass. Every few years someone spins a wheel and determines the next big thing that everyone needs to do to prevent batteries from dying early. For a while people were told full cycles were healthy for avoiding cell memory. Now more sporadic cycles are being peddled.
Use the device as you need it. If you complete a full cycle, cool; if not, that’s fine. Just don’t let the damn thing completely die and don’t keep it permanently on charge. Those are the common things most people do on accident that can really screw up a cell.
It isn’t spinning a wheel though, the advice hasn’t changed in decades (I’ve written something like the above comment at least a dozen times on Reddit since 2008 when I worked in the industry). Rather you might be getting it confused with other cell chemistries. Memory is a problem for NiCd cells, which were popular a long time ago, but even once we moved to NiMH for most things and then Li-ion there is no concern about it. Unfortunately there is a ton of incorrect and bad information out there about batteries so it is hard to wade through the crap and find the real information.
https://batteryuniversity.com is the best resource I know for correct information about li-ion cells, since it is written and maintained by a company that designs battery testing equipment.
Part of the problem is the game of telephone drops the cell chemistry related to the method almost immediately leading to general consumers applying it as a blanket rule for all batteries
Interesting source though…
About 4, I’d start long term storage from 80% because self-discharge rate is 30% per year in room temperature, or 15% per year in the fridge, which is the best storage temperature. Also, Battery University said in some article that 65% charge is optimal for storage, which is ~3.95V/cell at rest for most chemistries.
The reason I said 40-60% is because over that entire range both self-discharge and permanent capacity loss happen at their slowest rates because that is the flat range of the voltage curve where the cell is close to its nominal 3.7V voltage. The self-discharge with starting at 80% will maybe buy you an extra couple months before the cell becomes unusable, but you would experience more irreversible capacity loss.
Yeah, that’s been my whole experience surrounding people being upset that batteries aren’t able to be replaced in phones anymore. Don’t get me wrong, I’m not saying it’s a good habit, but I’ve never had a phone long enough for the battery’s life to degrade to the point where that degradation was more than mildy noticeable.
Maybe that says more about your phone consumption than battery life.
I try not to buy a new phone every year and I can tell you, after 3-4 years, the batteries are very noticeably dying. My last two phones (nexus 4, moto z play) both were replaced due to failing batteries, since replacing them is almost impossible (I couldn’t even find replacements that I would call trustworthy).
My usage was not super unusual, and most days I plugged them in over night and that’s it.
It can also depend on the device. I’ve had smaller devices and have had to charge multiple times a day. After getting a bigger phone with a bigger battery. I simply don’t think about it anymore. I imagine my phone dying before the battery does or even if it does, I’ll pay for a replacement if needed. I’d rather not stress in the day to day.
Here’s my headline: Why obsessing over battery degradation is unhealthy and you should just do whatever is easiest for you
Agreed. If you’re a device maker and you haven’t considered the possibility of your users plugging in their devices for long periods of time in your design, then i feel that’s on you to improve your product.
I have enabled the option to limit charging to 85% on my Samsung, and last weekend I needed it to last for 2 days so I charged it to 100%. Easily made it. It’s nice to know you have that 100% when you need it .
… Aren’t devices designed to only charge the battery to 90% (and report that as 100%), because actually changing a battery to 100% is pretty harmful for it?
You’re thinking of cars, industry and others that have high value batteries.
Power tools, smartphones etc charge to the maximum 4.2V/cell, sometimes even 4.3V (some chemistries safely allow it) because the average person just wants the maximum runtime and will replace the equipment before the battery degrades significantly.
I plug all my devices directly into the power line pole outside; everything charges to 75000%
Before spontaneously combusting
At the risk of sounding like Spinal Tap, why don’t they just make the chargers stop at 80% and have the interface show 100%?
Edit: woops. Appears that’s already a thing.
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This should not only result in government regulation where artificial battery killing is prohibited, it should result it jailing execs who decided this was a good idea.
I don’t know, I have a bunch of years old Sony Konion vtc5 and vtc6 18650s, they’re constantly loaded and drained, I guess some have thousands of cycles. Of course, they’re not new anymore, but even my oldest ones, 7 years plus, are ok. They still give 34 ampere for quite some time, so no problems here. Got some even older no-name ones in akku packs, 10 years old, not so many cycles, no problems there either. Maybe because I never charged them quickly and with adaptive voltage?!?
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So my battery is at 85 and Im Supposed to wake up to it at 50 instead of plugging it in? This is a engineering issue.
Your phone drains 35% while idle overnight?
They talk about Apple but Sony phones have had this feature for a while. In the settings you can choose whether the phone is always 100% charged, or whether it charges to 80% (or a custom %) or whether you want it full by the time you wake up.
I use the 3rd option. It stops charging when it gets to 90% and I tell it when I’m getting up, and just before it will charge up to 100 %.
Best of both worlds. Only ever having 80% to start is not nice because you get less juice during the day and need to charge by the evening. Plus battery anxiety. I’d rather have a 100% full battery.
Clearly newer, better battery tech is needed. Plus replaceable batteries.
Samsung, too.
I use it because I want my phone to last as long as possible, but the downside is that it won’t last a day so I have to charge in between. Ironic, isn’t it?
Very ironic.
That’s why I just tell it to be full by morning because I purposely bought a phone with a great battery . Why would I want to hamper it by 20%???
My Galaxy s22 has an option “battery protection” that limits my battery charging to 85%. Looks like they had a good idea there.
I didn’t realize I had this option. Thanks so much!
I’m convinced that apples laptop battery saver feature that’s AI powered and decides when to charge above 80% vs just letting you set it to 80% and manually set it to 100% when needed is to cause the batteries to die sooner, because ITS GOD AWFUL AT DOING ITS JOB PROPERLY.
I have a Dell Laptop (Latitude 7390) where I changed in the bios some option to maximize battery longevity and 6 years later it still lasts quite a lot.
I have a POS HP from nine years ago and the battery still lasts two hours. Just depends on the battery size I guess
Degraded battery life is rarely the thing that tanks a device for me (sure, it degrades, but it’s rarely the reason I replace it). I mean it’s great to know about this, but the last four phones I’ve replaced have been because (a) my old phone didn’t work on my new network, (b) my camera failed, © my chipset wasn’t up to the task of the most recent OS update, and (d) there was a fundamental flaw in my handset and the manufacturer offered a $50 upgrade to their newer model with trade.
Actually, thinking about it, a and b might be switched, but the point stands: it’s probably been twenty years since battery life was the reason I upgraded (from a flip phone to another flip phone, iirc).
I still charge to 100, but I use a slow charger, so my phone doesn’t start to spew flames while it’s charging. I wouldn’t be surprised if that helped as well (as heat is another battery killer).
I just can’t be bothered to handle that shit manually.
I charge all my shit to 100% with a fast charger, always have, and it all works great.
This “issue” is severely overblown.
Same, agreed. To me it’s a bizarre topic for people to have an opinion on.
its an easy way to obsess over something that will make at most a tiny marginal difference.
“whoa your phone lasts 4% more than mine because you obsessively babysat every charge session to perfection in the past 5 years? good one champ, I was instead enjoying my life”
not going to trust a website that makes money from repairing phones
also a lot of armchair battery scientists in here
iFixit has been pushing phone repairability and right to repair for years. Sure, that makes it easier for them make repairs, but it also helps users repair their own devices. For example, in the article they mention their stance that phones should have removable batteries so that instead of having to take a phone in to get the battery repaired or replaced, you can just swap it yourself. Personally, I want to use my device as long as possible before I’m forced to buy a new one, so I’m happy to have more ways to fix issues myself.
They also have a shit ton of guides on their website that show step by step how to make various repairs, and they are free.
IFixit aren’t the bad guys here
I want to correct you but I like it better that way. I want to be an armchair battery scientist when I grow up.
