Everything you need to know about charging Galaxy S8 battery: what chargers can be used to charge Galaxy S8 battery, how to use a wall charger, wireless charger or fast wireless charger to charge the battery in Galaxy S8 and S8+, how to disable fast charging or fast wireless charging in Galaxy S8 and S8+, and how to properly charge Galaxy S8 battery.
Samsung Galaxy S8 and S8+ use a non-removable battery, which can only be replaced at Samsung service center. It is impossible to carry a spare battery for Galaxy S8 or S8+.
So, it is important to charge Galaxy S8 battery properly to let the battery serve you at least one to two years.
What chargers can be used to charge Galaxy S8 battery?
Of course, you can use other chargers to charge Galaxy S8 battery.
Namely, you can use any of the 4 types of chargers to charge the battery in Galaxy S8 and S8+:
- adaptive wall charger (fast charger) included in the Galaxy S8 box;
- standard USB wall charger;
- wireless charging pad; or
- fast charging wireless charging pad.
Adaptive wall charger (fast charger)
The bundled wall charger in the box is an adaptive charger, which can adjust its output based on feedback from the phone.
In other words, the adaptive wall charger will automatically adjust the charging power to offer fast charging.
For Galaxy S8 and S8+, the adaptive wall charger can charge Galaxy S8 battery at 9v 1.67A when the battery level is lower than about 60%.
When battery level is higher than about 60%, the wall charger will automatically switch charging voltage to 5V and charging current up to 2A.
So, when using an adaptive wall charger, you can shorten the charging time up to 50% for the first 60% of the battery. For the remaining 40%, fast charging is automatically disabled and adaptive wall charger works like normal wall charger with 2A output.
Please note, the actual charging current is regulated by the charging circuit. 2A is the maximum charging current.
Standard USB wall charger
You can use any standard USB wall chargers (like this one) to charge Galaxy S8 battery.
Your old chargers from Samsung or any other phone vendors can be used to charge Galaxy S8 and S8+ without issues.
Please note, although you can use old charge, you may not be able to use the old micro USB cable. Galaxy S8 and S8+ requires USB type-C cable. To use your old micro USB cable to charge Galaxy S8 battery, you need to use the micro USB connector (adapter) in Galaxy S8 box (read on).
You should use quality or branded wall charger. Don’t destroy your $700+ Galaxy S8 with a low-quality charger.
Wireless changing pad (wireless charger)
Your old wireless charger for Galaxy S6, Galaxy S6 edge, Galaxy Note 5, Galaxy S7, Galaxy S7 edge and many other Galaxy devices should work with Galaxy S8 and S8+.
Of course, you can get a Samsung branded wireless charger for less than $20.
Fast charging wireless charging pad (fast wireless charger)
Galaxy S8 and S8+ also support fast wireless charging.
The fast charging wireless charging pad requires an adaptive wall charger (fast charger).
The maximum current output of fast wireless charging pad is still 1000mA (1A), which is identical to that of wireless charging pad.
But the 9V charging voltage makes it faster than normal wireless charging (which can only charge Galaxy S8 battery at 5V). Samsung claims fast wireless charging pad would be 1.4x faster based on their test.
Comparing of Galaxy S8 battery charging time with different chargers
Galaxy S8 battery charging time always varies due to many factors including:
- ambient temperature;
- ambient ventilation;
- activities on the phone including background processes when charging;
- the age of the battery;
- previous usage of the battery;
- USB cable used.
So, your actual charging time may be differ from the numbers we will discuss below.
The purpose of the comparison is to show you the impact of the charger on charging time only.
The table below shows the typical charging time from about 2-4% to fully charged. The phone was on, but screen was off during charging. Airplane mode was also enabled during the test.
Typical battery charging time of Galaxy S8 and S8+
|charger||Galaxy S8||Galaxy S8+|
|1A USB wall charger||3-3.3 hours|
|2A USB wall charger||1.5-1.7 hours|
|Adaptive wall charger(fast charger)||1.25-1.4 hours|
(75- 85 mins)
|Wireless charging pad (normal)||3.2-3.6 hours|
|Fast wireless charging pad||2-2.4 hours|
(148- 182 mins)
Please note, this is not a scientific research. We simply recorded the charging time without singling out any other factors.
But the table should give you a rough idea on the differences of Galaxy S8 and S8+ battery charging time when different chargers are used.
How to use wall charger to charge Galaxy S8 battery?
You may follow these steps to charge Galaxy S8 battery with a wall charger (normal or adaptive/fast charger)
Step 1: Insert the USB cable into the USB port in Galaxy S8 or S8+
The USB port in Galaxy S8 and S8+ is USB type-C. This means you have to use an USB cable with type-C connector.
You cannot use old micro USB cables directly in Galaxy S8 or S8+. But the USB cable of Galaxy Note 7 can be used if you have any.
Anyway, you can find the USB type-C cable in your Galaxy S8 box.
USB type-C connector is symmetric. You can inset the cable into Galaxy S8 or S8+ in any directions as shown below.
Step 2: Connect the USB cable to the charging head
Step 3: Plug the charging head into a power outlet
You can use power extension socket if needed.
Fast charging does NOT require a special socket. As long as the socket provides power with proper voltage and frequency, fast charging will work.
Step 4: Wait till Galaxy S8 battery is fully charged
You should not use Galaxy S8 or S8+ heavily when it is being charged.
Also, you should wait till Galaxy S8 battery is fully charged, which will be indicated by a green LED indicator on the phone.
Step 5: Unplug the charging head from the outlet and remove the USB cable from the device
To save power, you should disconnect the charger from the power socket because wall charger cannot turn itself off.
How to use wireless charger and fast wireless charger to charger to charge Galaxy S8 battery?
In addition to charging Galaxy S8 and Galaxy S8+ using USB cable, you can use a wireless charging pad or a fast charging wireless charging pad, to charge Galaxy S8 battery.
You may follow these steps to charge Galaxy S8 battery with a wireless charging pad or a fast wireless charging pad.
Step 1: Power on wireless charger
Normally, a wireless charging pad requires a wall adapter (wall charger). You need to connect the wireless charging pad to the adapter with an USB cable.
Please note, some wireless charging pads require micro USB cable, and some may require USB type-C cable.
Then power on the adapter.
Step 2: Put Galaxy S8 or S8+ on the wireless charging pad
You may refer to Galaxy S8 layout and Galaxy S8+ layout to find out the rough location of the wireless charging coil.
When you put Galaxy S8 or S8+ on the wireless charging pad, you need to make sure the charging coil part is close to the center of the charging pad as shown below.
If the wireless charging coil part of Galaxy S8 or S8+ is too far from the center of the wireless charging pad, your phone may be not charged, or will be charged in a very slow speed.
Step 3: Wait till Galaxy S8 or S8+ is fully charged
Normally, the wireless charging pad will display a color to indicate that charging is in progress. Of course, this depends on individual brand.
When Galaxy S8 battery is fully charged, the wireless charging pad usually changes color.
For example, for Samsung branded wireless charging pad, the blue color indicates wireless charging is in progress, and green color indicates Galaxy S8 or S8+ is fully charged.
If you are using a fast wireless charging pad to charge Galaxy S8 battery, do not block vents (small holes) near the bottom of the charging pad.
Step 4: Remove Galaxy S8 or S8+ from the wireless charging pad
Normally, it is safe to leave the phone on the wireless charging pad because wireless charging pad will cut off current supply when Galaxy S8 battery is fully charged.
But the wireless charging pad itself may waste some energy when it is not charging any devices.
How to disable fast changing in Galaxy S8 and S8+?
First, fast charging is a good technology. It reduce your charging time.
Most claims on the side effects of fast charging are usually based on outdated research or data.
The current battery technology allows you to charge the battery at a faster speed without affecting battery lifespan. The charging control mechanism is very matured now.
So, it is NOT necessary to disable fast charging.
But if you still want to disable fast charging or fast wireless charging, you are free to do it (because it is your phone!)
To disable fast charging and fast wireless charging in Galaxy S8 and S8+, go to Settings — Device maintenance —Battery —menu key (3 vertical dots near top right)– Advanced settings. You can then turn off or turn on fast cable charging and fast wireless charging.
How to properly charge Galaxy S8 battery?
There are many tips and tricks on how to properly charge Galaxy S8 battery, or how to prolong the battery life for Galaxy S8 and S8+.
Most of them are outdated. Some are deadly wrong.
Here are some principles on charging Galaxy S8 battery properly.
- Your Galaxy S8 0r S8+ should serve you. You are not the servant of the phone. Your usage and convenience are more important than anything else. You get the better ROI if Galaxy S8 or S8 makes you more productive, or make you happier.
- You will replace the Galaxy S8 or S8+ battery within 12-24 months for heavy users (e.g., charging the battery more than once each day in average), 24-36 months for normal users.
- The shelf life span of most lithium-ion polymer battery (which was used in Galaxy S8 and S8+) is about 3-6 years.
- Charge Galaxy S8 battery only when you need to do so. You should know whether you can charge it later and whether the battery can last till you can charge it.
- Don’t disconnect Galaxy S8 or S8+ from the charger before it is fully charged unless it is an urgent case.
- Don’t drain Galaxy S8 battery completely. This may cause damages to both the battery and other components in Galaxy S8 or Galaxy S8+, although Galaxy S8 or S8+ will automatically turn itself off when battery level is critically low.
- Leaving Galaxy S8 0r S8+ on the charger overnight is not wrong. Of course, it is not a good habit. But it is OK.
- If convenient, it is a good habit to disconnect the charger from galaxy S8 or S8 once battery is fully charged.
- Minimize the usage of Galaxy S8 or S8+ when it is being charged. You can try to find a book to read.
- Use quality charger.
- Use quality USB cable.
- Fast charging or fast wireless charging will NOT noticeably affect battery life of Galaxy S8 and S8+.
Should I charge Galaxy S8 battery for 8 hours before using the phone first time?
No, it is not necessary to charge Galaxy S8 battery for 8 hours before using the phone.
In some regions, Samsung does not offer 1-1 exchange. You have to test Galaxy S8 or S8+ on the spot. If you find any problems after leaving the shop, you may have to visit service center to repair.
The battery in new Galaxy S8 or S8+ is always pre-charged to about 50% for you to test.
Of course, if you want to leave the new phone on the charger for 8 hours, it does not harm either.
How to use micro USB cable to charge Galaxy S8 battery?
You may have a lot of micro USB cables at home or office.
By default, you cannot use them to charge Galaxy S8 battery because Galaxy S8 and S8+ use USB-C port, which requires a USB Type-C cable.
But you can connect micro USB cable to the micro USB connector (which can be found in the Galaxy S8 box as discussed in this post.), then insert the micro USB connector (adapter) to Galaxy S8 or S8+, as shown below.
In this way, you can use micro US cable to charge Galaxy S8 battery.
You should NEVER plug a micro USB cable directly into Galaxy S8 or S8+. You will very likely damage the your Galaxy S8 or S8+!!!!!
My Galaxy S8 charging time is far longer than normal, what makes it slower to charge Galaxy S8 battery (or S8+ battery)?
The Galaxy S8 charging time discussed above is on a new phone with only a few apps.
In addition, we set the phone in airplane mode and did not use it during charging.
In real life, the charging time for your Galaxy S8 or S8+ may be a bit longer. But the difference should not be significant.
Here are some possible causes that may slow down the charging:
- Try to use the bundled USB cable, or branded USB-C cables.
- Make sure USB cable is inserted tightly in both ends: one to the adapter, and the other to the phone. If the cable is not inserted tightly, it may slow down the charging significantly.
- The ambient temperature is too high.
- You are using the phone heavily (for example, playing games) when charging.
- If you are using fast wireless charging, make sure, the vents in the charging pad are not blocked.
- If you are using fast wireless charging, you must connect the wireless charging pad to an adaptive wall charger (fast wall charger).
- If you are using wireless charging (not fast wireless charging), you must connect the wireless charging pad to a 5V 2A wall charger or an adaptive wall charger. If you connect the wireless charging pad to a wall charger with less than 2A output, the charging can be very slow.
- The phone is running some heavy background jobs, for example, updating apps, download large files.
Why I cannot charge my Galaxy S8 battery when I Got “Check port, moisture has been detected… “?
If you got the “Check port, moisture has been detected… ” message, it means Galaxy S8 or S*+ detected moisture in the USB port. To protect the USB port from irreparable damages, Samsung prevents you from charging Galaxy S8 or S8+ through the USB port.
You can then only charge Galaxy S8 battery through wireless charging.
Please refer to this guide on how to solve Galaxy S8 moisture problem.
Can you charge Galaxy S8 battery now? Do you have any questions on charging Galaxy S8 or S8+?
If you have any questions or encounter any problems to charge Galaxy S8 and S8+, please let us know them in the comment box below.
The community will help you find the answer or solution.
You may also check our Galaxy S8 guides:
- Galaxy S8 new features guide covers all new and unique features of Galaxy S8 and S8+.
- Galaxy S8 how-to guides give you detailed step-by-step guides on using most features of Galaxy S8 and S8+.
- Galaxy S8 user manuals lets you download official Samsung Galaxy S8 user manuals in your won language.
- Galaxy S8 camera guides covered everything related to Galaxy S8 camera is covered in Galaxy S8 camera guides section.
- Galaxy S8 accessories guides help you find the perfect accessories for Galaxy S8 and S8+.
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