Proper and safe charging... what's "correct"?

[Pixel Hunter]

I did search, but didn't find an answer to my specific questions. So apologies if this has been discussed and I missed it.

I've seen a lot of differing opinions and information about charging the S24+ (or other modern phones) which makes it hard to know what's fact and what's fallacy. Such as:

• Don't use wireless charging. It is less efficient and heats up the phone/battery, reducing battery lifespan.
• Don't charge past 80% if you want to maximize the battery life.
• Slow charging (low wattage) is better than fast charging (high wattage).
• Super-Fast wireless charging is the best!
• Get a 25W charger, you don't need anything more. No... get a 5W charger. No... 45W! Are you kidding, you need 65W or 100W!!!

Argh! So here I sit, head spinning, and I'm not sure what I should do. I've been using a cheap wireless charger for years on my iPhones. I don't even know what wattage it is! But since I switched to an S24+, I've been doing a lot of research and these questions are coming up and I'm uncertain what I should get. If I need to get anything at all.

Let's say I just want to safely and efficiently charge my phone. No overheating. No fires. Typically overnight on my nightstand. I want the phone/battery to last the three years of the device payments. What do I buy? Or do I just keep using the ??W wireless charger I already have?

 

[B. Diddy]

The 80-40 guideline (i.e., don't charge past 80%, and don't let it drop to <40%) can technically prolong your lithium battery's lifespan (https://batteryuniversity.com/article/bu-808-how-to-prolong-lithium-based-batteries), but from a practical standpoint, this isn't that convenient nor feasible. I typically charge my phone to 100% overnight, and try not to let it get much below 30-40%, and after more than 2 years, I haven't noticed any significant degradation. My feeling is that following the 80-40 guideline might give you an extra 1-2 years of decent battery life, but this would be beyond the typical 4-5 years I would expect from the habits I use. The average person will upgrade their phone after 2-3 years, so it's generally not going to be an issue. For my EV, though, I do make sure to limit the charge to 80% on a regular basis, because I definitely want to keep those batteries as healthy as possible for as long as possible.

I don't have any strong opinions about your other questions. I do use my Pixel Stand to charge my Pixel 7 Pro regularly, and have not noticed any issues. The one thing I would suggest if using wireless charging is to make sure the case dissipates heat efficiently. If the phone is getting pretty warm while charging wirelessly, it may have more to do with the case than the phone, and the heat generated could impact the battery over time.

 

[pags11]

I try to keep the battery percentage on my S24 Ultra between 40% and 85%. This seems to help with the battery being solid during the life of my phone.

 

[cohoman]

I normally have my phone on a wireless charger at home and at work when I'm my respective desks. My battery level usually doesn't fall below 60% during the day unless I have the screen on for hours playing a game. I also wirelessly charge my phone every night to 100%.

After doing this for 18 months with my S23 phone, the battery swelled up and popped off the back cover. I was able to repair it for free under the Samsung Care+ warranty. It made me wonder if all that wireless charging caused the battery to swell, or was it a coincidence and I just had a bad battery.

 

[gomezz]

In the absence of any scientific studies on how charging practices affect battery life I would take all these guidelines cover them liberally with salt and throw them in the trash.

 

[vader4633]

If using a 45 watt or more charger, make sure you have a usb cable that supports the 45 watt or more charging so you see it indicates super fast charging 2.0.

Usually just charge my s24 ultra with a 45 watt charger before I go to bed. Haven't charged it overnight. At most it needs an hour to fully charge. I'll put it on the charger to give me some more juice in the afternoon if I'm going out for the night.

Had a s21 ultra for 3 years and charged it overnight all the time. Never felt the battery lost anything in that time.

 

[Mooncatt]

In the absence of any scientific studies on how charging practices affect battery life I would take all these guidelines cover them liberally with salt and throw them in the trash.

The Battery University link B. Diddy posted above is full of results from scientific testing. The caveat is they are looking at it from a best practices point of view, and it'll be up to each person how to beat adapt it to their situation.

For example, Diddy said it isn't practical to keep between 40-80%. That may be true for him, but it's no problem for me to do that. That's also helped by more phones now allowing charging to stop at around 80% even if they are still plugged in.

 

[mustang7757]

I normally have my phone on a wireless charger at home and at work when I'm my respective desks. My battery level usually doesn't fall below 60% during the day unless I have the screen on for hours playing a game. I also wirelessly charge my phone every night to 100%.

After doing this for 18 months with my S23 phone, the battery swelled up and popped off the back cover. I was able to repair it for free under the Samsung Care+ warranty. It made me wonder if all that wireless charging caused the battery to swell, or was it a coincidence and I just had a bad battery.

Ouch ..I had that happen to my s8 the battery swelled and popped the back glass clean off

 

[Pixel Hunter]

So...

I think my wireless Qi charger is only 7W, so I don't think I need to worry too much about overheating the phone/battery or depleting the lifespan with that. But if I wanted to play it even safer, I should (in theory):
1. Cable charge
2. Use the phone settings battery protection (I currently have it set to Adaptive)
3. Even if using a 45/65W+ charger, don't turn on Fast Charging unless I need a full charge quickly

That said, I think I might grab a 45W PD capable charger (or maybe 65W) along with a USB-C PD capable cable and use that as my primary charger. I can put my 7W Qi charger on my desk for supplemental charging.

Any recommendations for brand chargers and cables to pick up? Amazon is full of funky-no-name Chinese stuff.

 

[B. Diddy]

Anker and Belkin are both well-respected brands.

 

[vader4633]

If I do charge at night, I do have a routine setup.

 

[ralfyguy]

I normally have my phone on a wireless charger at home and at work when I'm my respective desks. My battery level usually doesn't fall below 60% during the day unless I have the screen on for hours playing a game. I also wirelessly charge my phone every night to 100%.

After doing this for 18 months with my S23 phone, the battery swelled up and popped off the back cover. I was able to repair it for free under the Samsung Care+ warranty. It made me wonder if all that wireless charging caused the battery to swell, or was it a coincidence and I just had a bad battery.

I charged my Note 10 wireless every night to 100% And used about half that during the day. Was still going strong until Samsung bricked it with that one update.