How to charge Galaxy S9 battery?

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• Recently the notification light on my S9 would not turn green when fully charged. I dont know why but it doesnt turn green anymore. Its just red when being charged and stays red when it reaches 100%.

  • It turned green only when it states charged.

    100% is only an estimation. "Charged" is a physicals state.

    So it usually takes a few mins from 100% to charged. The duration depends on many factors. Anything below 30 mins with a 5w-10w charger in normal.

    Anyway, you should wait a while.

• How long will a fully charged Galaxy S9 battery last with normal use

  • It highly depends on usage. Mobile network signal strength and quality also affect battery life significantly.

    Normally, the battery should last one day. You should get about 3-5 hours screen-on time. Anyway, most of these flagship phones are designed to work one day so that you don't need to charge it during the day. But normally, it's not enough for two full days.

• As a long time support rep I must say Very Good and Informative. I also admit that I learned from this. Thank you

• I just purchased a Samsung S9+ & fell asleep using it from it's boxed charge. When I awoke, the battery was dead.I have just read "Never, never let the phone power off automatically due to a drained battery. What will happen now!?????

  • It's ok. Take it easy. You can charge the battery then use it normally.

    Just try not to let it happen frequently.

• Can I charge my Samsung Galaxy S9 overnight ?

  • It's ok. It's not necessary to get up at 3am to unplug the phone from the charger.

• Great article!! Quick question...is it harmful to the battery if you do charge it when it's not necessary, ie at 60% let's say? Does charging it too much decrease the life and efficiency of the battery? Thanks!!

  • It is not good for the battery. It may increase the wear and tear.

    But if you just do it occasionally, it should be OK. Anyway, you should estimate whether the battery can last till you have time to charge the battery. If it is not enough, you may charge it even it is over 80%. It is not wise to sacrifice your usage.

• Thank you for information. My phone is about a month old and I have been charging it just about every night - hopefully I haven't done too much damage already! I will certainly hold off on charging it until the battery is "low" going forward. Is there any type of cycling that should be done to increase the "health" of the battery? Thanks!

  • It depends on your usage. If the battery is enough for the next day, then it is not necessary to charge it. But if not, you should charge it. Always put YOU above the phone.

    The battery will lose capacities no matter what you do to it. But good habits may slow down the speed. The good habits include: 1. charge the battery only when it is needed; 2). charge the battery to full; 3). do not use the phone heavily (e.g., playing games) when it is being charged; 4). don't let the battery shutdown itself.

    Anyway, you get the highest ROI if you can enjoy the phone for 2-3 years. Don't let it become a burden.

• Just purchased an Galaxy S9 and wondered about charging and using it in our Honda
  CR-Vs (both have USB ports for phone/other accessory use). I understand that charging thru these will not get the adaptive benefit but is it save otherwise if one has a USB to USB-C cable? When I travel with my old LG, I usually plug it in and let it charge if needed (don't usually use Android Auto). Just wanted some info from other S9 users who may have used this method to keep the phone charged while using Bluetooth to get the CR-V's Hands Free access to keep up with incoming calls and texts.
  Thanks from an S9 Newbie.
  John

  • Not sure about CR-V. The usb port for the head unit normally provides low power output. Many new cars offer a usb charging port in addition to the USB port for HU. If you don't use Android Auto, you may try this port.

    You can also buy a car charger. Some offer fast charging.

    The type of the cable doesn't matter. Quality matters.

• What percentage of the battery is the best time to charge the samsung S9

  • Charge the battery if the battery cannot last before you can access the charger again. In other words, you need to charge Galaxy S9 battery only if you need to do so.

    Normally, you should not let the phone power itself automatically due to low battery.

• Just purchased a new S9 yesterday. I was always under the impression that draining the battery before the first charge is best. Now reading up on it I'm learning that that's not the case. Did I damage my battery by draining it completely yesterday after buying it?!????

  • it should be ok. if you frequently (e.g. a few times a week) drain the battery completely, it may shorten the battery life. If you just did it occasionally, it should not affect the battery.

• I contacted Samsung. They say it is harmful to charge the galany so overnight.

  • It's just not a good habit. It's not good for the battery.

    But the "damage" should be very marginal, compared to the inconvenience if you don't do it (e.g., get up in wee hours to disconnect the charger).

• I just bought a new S9+, and usually in college I just charge my phone overnight (although my prior phone's battery was crap, 4 years old and bought from someone else (second hand)). So I thought about this as well.

  I was looking for some method to slow down the charging every night, and I think that the "disable fast charging" option is just fenomenal for this. I was thinking in buying some 5W charger from Aukey or similar, that would be ideal, but maybe the 10W option is just fine. Again, just for charging overnight, obviously full speed on a rush!

  What are your thoughts about my plan?

  • If you want, you can get a 5w charger. You need to get a quality one. Don't use unknown brands.

    But I would say it's probably not necessarily. Once the battery is fully charged, a tracking current will be maintained because the phone cannot turn off the wall charger. This may slightly affect the battery life span. But the impact should be very marginal.

• At what percent should I charge my phone if access to a charger is not an issue?

  • Normally after 20%. Once in while you may want to let the battery drain to 5% or less.

• I noticed that when I used the smart switch with a power bank, there is options to charge your galaxy S9 or charge the connected device.
  I could not select the option to charge the S9 using the smart switch from power bank? Why? How can I do it?

  • Smart watch?

    You can charge Galaxy S9 battery through the USB C port. At the same time, when another device is connected to the Galaxy S9 through USB C port, Galaxy S9 can charge it as well. Of course, in this case, you can disable the charging.

• Wenever i charge my s9plus, i keep in fast charge... is there any problem.? Coz i heard tht if v put our phone in fast charge mode , it may decrease the life of battery.???

  • It should be ok. If there is any impact, it should be very marginal. Enjoying the phone gives the highest ROI.

• Will my s9 accept a charge rate or voltage that is too high for it? For instance from a usb-c computer power cord.
  Will it fry the battery or just simply not charge. If the charging Icon turns on can I assume it's ok? I not looking for hyper charge rates just convenience sake if the only charger I have is a usb-c laptop charger.

  • It depends on the charger. The phone has it's mechanisms to protect the battery by regulating the current and voltage it accepts. Most high-power USB C chargers can communicate with the phone to deliver corrupted correct current and voltage.

    Normally, you should not worry about it as long as it follows USB C standards.

    But the battery will not charge faster when you use chargers with a higher rated output power. 15w (9v, 1.67A) is the maximum charging rate for s9 and s9+.

• You say not to use the phone while charging. But, then I saw a comment saying use for high energy uses, such as gaming were discouraged. In the past, I have typically charged by phone during the day and made or answered calls using a Bluetooth ear piece. Will this kind of use damage the battery? Also, I don't quite understand how you could not use it while charging because email, etc. is always coming through. Should you power off while charging?

  • It's ok to use the phone lightly when it's being charged. You should not use it heavily (e.g., playing games) when charging the battery. The keypoint is "trying" to minimize the active usage of the phone when charging the battery.

• how long do I need to charge my samsung s9 for the first time??

  • Once time battery is full, you can disconnect thr charger, even for the first time.

    There are no special requirements for the first time charging.

    But you should try to wait until it's ” charged", not just 100%. The notification led should turn from red to green (if you don't have other notifications) once the battery is fully charged.

• can you recommend a brand or a specific car charger and a wall charger for s9 plus?

  • For wall charger, Samsung ones are very good and durable. You can get a spare one for a few bucks.

    The car charger, I have used the Anker 24W one with two charging ports. One of them supports Quick charge. Mine is an old model.There are several new models. Anyway, I prefer that brand. It will cost you about $10-20 on Amazon.

• thank you

• I have the accubattery app that monitors battery usage. It also notifies me when to charge the phone (at 20%) and when to stop charging (at 80%). The upper end seems to differ from your recommendation to charge all the way to 100%. Accubattery says that keeping the charge range between 20 and 80% will extend battery life. Is that correct? You seem to recommend charging to 100%, and occasionally dropping all the way down to 5%. Thanks.

  • It's hard to tell because there haven't been many scientific researches on this. Also battery technology evolves quickly.

    Normally, when you store the battery for an extended period, it's the common practice to charge it to 50%-80%. But for daily usage, there is no reason to charge it only to 80%. If you do, you actually need to charge 25% more times.

• I have mi 2i power bank . Somebody says it is harmful to charge with a power bank.. i should use it when extremely necessary of this.. i checked, this power bank can deliver as much as current s9 plus requied .. what is your opinion ? Should i continue charging with power bank regularly ?

  • Normally, power bank is not the issue. It will not damage the s9 battery. The quality of the power bank is important.

    Normally, a wall charger can regulate the current better than a power bank. But a high quality power bank can just do it like a wall charger.

• OK, so you are not to let galaxy S9 power off by draining the battery. Is there a notice of some time of a low battery to know to charge? The LG phones have that feature; why not the great galaxy phones?

  • Yes, this feature is missing on Samsung phones. Normally, you need to check the status bar. When battery level is lower than 15%, a red symbol will appear in the battery icon.

• I have the Samsung Galaxy S9 and want to buy a power bank because we live in the country and lose power frequently. Is it safe to use the Anker PowerCore II 20000 power bank?

  • Yes, it is safe to use. Anker products usually have high quality with a relatively low price tag.

• I just wanted to say thank you : )