What to do if Note8 battery drains quicker after an update [troubleshooting guide]

Today’s post hopes to help those #GalaxyNote8 users who are experiencing problems after installing a system update. We know that the phenomenon is usually more about perception rather than a real issue but we want to address it nevertheless to educate everyone. We hope this post will help.

How Lithium-based batteries work

All smartphone batteries, including the ones on Samsung Galaxy devices, are using Lithium chemistry. At this time, there’s no better alternative or one that can challenge its commercial success. A Lithium-battery relies on the movement of ions in order to work. Basically, these ions move between positive and negative electrodes to produce energy. Theoretically, such movement should last forever but unfortunately, there are other factors that that affect such movement, causing a lithium battery to eventually die out. Ions cannot continue to work between these positive and negative nodes forever  as high temperature, cycling, and physical degradation of the cell all affects the performance. In other words, Lithium batteries can only last for so long. If you tend to charge your battery at least once a day, you should start seeing performance degradation after about a year.

If your Note8 battery seemed to have significantly shortened its performance after installing a system update, there must be other reasons for it aside from the natural degradation it’s supposed to have.

Use your device smartly

One important thing to remember when it comes to managing your Note8’s battery performance is to be smart. As long as your Note8 is powered on, it bleeds battery power so all you have to do is to ensure that you minimize it. The more apps you open and leave running in the background, the faster the battery drains. Even if you’re not actively using an app, it may remain working in the background. The more apps and services running in the background, the faster your battery bleeds.


We understand that you bought your phone to use it but given the reality of how limited its power source is, you should also consider changing usage habits. We won’t dictate how exactly you’ll do that but keeping in mind that everytime you do something on the device affects the battery should be a good start. In other words, it’s up to you how you strategize in using your device day in and day out. Each of us has his/her own usage habits and as long as you’re aware that every task your Note8 does expends power, you’re in the right direction in fixing the issue.

For more concrete tips on how to deal with the perceived battery drain issue on your Note8 after an update, follow our suggestions below.

Tip #1: Wipe the cache partition

The first often suggested troubleshooting step when it comes to fixing post-update issues is cache partition wipe. That’s because a lot of bugs or annoyances are often due to a corrupted system cache. This cache sometimes becomes corrupted after installing an app or update. To check if you have a system cache issue, consider wiping the cache partition where it’s stored. Here’s how:

  1. Turn off the device.
  2. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
  3. When the Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds before showing the Android system recovery menu options).
  4. Press the Volume down key to highlight wipe cache partition.
  5. Press the Power key to select.
  6. Press the Volume down key to highlight “yes” and press the Power key to select.
  7. When the wipe cache partition is complete, “Reboot system now” is highlighted.
  8. Press the Power key to restart the device.
  9. Check for the problem by observing the device for a couple of days.

Tip #2: Lower screen brightness

Another good tip that you should do almost all the time, is to use screen brightness wisely. Sure, Samsung built the Note8 with a beautiful display capable of putting out an amazing color combination but it comes with a price. The huge, bright display of your Note8 is one of the biggest reason why your battery drains quicker than usual. We suggest that you lower screen brightness to the lowest available setting that’s comfortable for you and stick with it all the time.  Remember, the dimmer the screen, the less power it consumes.

Tip #3: Delete apps

In case you don’t know, the more apps you install, the more likely that the battery empties itself faster. Even if you’re not actively using apps, some of them or their associated services may still be running all the time — collecting information, communicating with remote servers, or doing whatever they’re supposed to do. The more apps of these type you have, the more your battery situation grow worse. That’s why sometimes, it pays to keep apps to bare minimum. Smart users always install only apps they need. If you have plenty of apps, we highly recommend that you go over all of them and see which of them can be deleted.

If you are constantly in need of longer battery life, we suggest that you check your apps to see which of them is a power-hungry one. There’s a built-in application that you can use to do this task. To open it, follow these steps:

  1. Open Settings app.
  2. Tap Device Maintenance.
  3. Tap Battery.
  4. Tap BATTERY USAGE button.
  5. From here on, you should be able to make informed decision what apps to uninstall to give your device a battery boost you may need.

Tip #4: Install app updates

Some apps may interfere with the operating system or behave erratically when they become incompatible with the current Android version you have. So, it goes without saying that you want to keep all of them up-to-date. Responsible app developers strive to minimize bugs on their products by regularly releasing updates. Most well-funded publishers do that and even then, issues can still occur from time to time. Think about apps built by resource-strapped developers. Remember, building and maintaining apps is expensive and since Android is constantly evolving, apps that don’t receive regular updates run the risk of becoming incompatible after some time. Make sure that you only install apps from reputable sources and avoid those from dubious developers. Before you install an app, be sure to check what others are saying about it. You can do that by checking reviews.

Whatever apps you decide to leave on the system, make sure that they are all updated to minimize the chance of having incompatible ones.

Tip #5: Change screen resolution

When it comes to bigger screens, having a higher resolution can significantly improve the quality of the photo or video being shown. However, in such a relatively smaller screen size, using low resolution is hardly noticeable. Your S8 has three resolution options that you can use and picking the highest one can dramatically consume more battery power. Try to pick the lowest possible and we can assure you, your photos and videos will still look great.

To change the screen resolution, just go to Settings > Display > Screen resolution.

Tip #6: Disable network services

If you’re in an area with poor signal reception, you’ll notice that your device will drain battery faster than expected, even if you’re not using it that much. That’s because your device’s network functionality is constantly busy scanning the airwaves hoping to get a better signal. If your network signal is weak and signal is constantly dropping, your Note8 will keep on working in the background to establish a good link. This task can become resource intensive overtime and can negatively impact battery performance. If you are in such situation, it’s better if you can simply turn Airplane Mode on. If this mode is enabled, all network functionalities such as Bluetooth, wifi, and mobile data will be disabled.

Tip #7: Stay away from Always On Display (AOD) feature

AOD, when used all the time, can contribute to fast battery drain issue. If you are concerned about battery performance getting shorted every day, turning this feature off might help.

Tip #8: Turn off Voice Assistants

Your Galaxy Note8 has at least 2 Assistants — Bixby and Google Assistant. Due to the nature of their task, these apps are always listening and awaiting for your commands, which can consume not just the battery but your cellular data as well. For many users, both are useless so if you’re not using them or any of them that much, we suggest that you ditch them.

Tip #9: Keep the screen off

After turning off AOD and Voice Assistants, the next good thing to do is minimize the waking time of your screen. As mentioned above, every task your Note8 does, including the ordinary one of keeping the screen powered on, is actually affecting the battery’s performance. We don’t mean to tell not to use your phone at all but only to make you aware that keeping the screen on for longer comes at at a price. If you find yourself in a long day and can’t possibly charge your device sooner, try to avoid turning the screen on as long as necessary.

Tip #10: Use Power Saving Mode

If you really want to extend battery performance and there’s no way you’ll be able to charge, you can consider transforming your device as a dumb phone by using Power Saving Mode. there are two such modes that you can use. To access Power Saving Mode, just go to Settings > Device maintenance > Battery.

Tip #11: Factory reset your S8

If your Note8’s battery still seem to be  draining quicker compared to when the update was not installed, try wiping the device to see if a reverting all software settings to defaults may help.

  1. Back up data on the internal memory. If you have signed into a Google account on the device, you have activated Anti-theft and will need your Google credentials to finish the Master reset.
  2. Turn off the device.
  3. Press and hold the Volume Up key and the Bixby key, then press and hold the Power key.
  4. When the Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds before showing the Android system recovery menu options).
  5. Press the Volume down key several times to highlight wipe data / factory reset.
  6. Press Power button to select.
  7. Press the Volume down key until Yes — delete all user data is highlighted.
  8. Press Power button to select and start the master reset.
  9. When the master reset is complete, “Reboot system now” is highlighted.
  10. Press the Power key to restart the device.