Expected battery life

[mark7914]

Samsung S8, bought January 2018.

All original firmware and OS. Software updates disabled to make sure it stays as perfect as when it was new. Which it is.

However the battery life - in the last two weeks in particular - is noticeably worse. 100% before going to bed, wake to 76%.

No new apps, no OS updates. Two apps permitted to update themselves in the last month - Twitter and Halifax. I have now stopped both of these from "running in the background" so we'll see how that goes.

How long might one expect a battery to last? For something costing about £650 if I remember rightly, I'd have thought maybe five years?

 

[B. Diddy]

Have you already checked to see which apps are using battery over that time period? Also, how's the cell signal where your phone rests at night? If it's poor, that can cause the battery drain fairly quickly.

 

[mark7914]

According to "Maintenance":

Halifax: 0.06%/hr
Twitter: 0.02%/hr

then

Malawarebytes 0.01%/hr

Those two were stopped from running in the background at the time of last post.

Down to 59% now - this is definitely draining faster than it used to. The drop seems quite rapid and sharp, suggesting a change rather than a gradual decline, but that needs proving - perception may not be reality

Usage today: one phone call, opened Twitter and Halifax app precisely once, used the timer once.

Reception is indeed poor here, phone is always on VoLTE, but has always been that way.

 

[B. Diddy]

If it's not crucial, try turning on Airplane Mode overnight and see if the battery still runs down that quickly. If it doesn't, that would point more to a reception issue.

 

[mark7914]

100% before bed - airplane mode off - wake to 76%
Same, but with airplane mode on - wake to 82%

I'm pretty sure this used to be well over 90%.

Either way, around the end of the work day it's down to around 55% and that didn't used to be the case.

I realise that might be something others would love to have, but bear in mind this isn't used much which is why the numbers are normally quite consistent and why the drop-off is noticeable.

It will still comfortably run for a day and a bit - it's just the "bit" is a bit less than once it was. The phone is also running just a little slower than once it did e.g. a slight pause between pressing something - like to open an app - and that happening. Used to run like lightning.

May be of interest to those who blame a software/OS update - this phone has never had one, all factory spec. I think this is probably just the decline of the battery. Seems a bit premature, but as long as it doesn't continue to drop it's fine.

 

[mustang7757]

100% before bed - airplane mode off - wake to 76%
Same, but with airplane mode on - wake to 82%

I'm pretty sure this used to be well over 90%.

Either way, around the end of the work day it's down to around 55% and that didn't used to be the case.

I realise that might be something others would love to have, but bear in mind this isn't used much which is why the numbers are normally quite consistent and why the drop-off is noticeable.

It will still comfortably run for a day and a bit - it's just the "bit" is a bit less than once it was. The phone is also running just a little slower than once it did e.g. a slight pause between pressing something - like to open an app - and that happening. Used to run like lightning.

May be of interest to those who blame a software/OS update - this phone has never had one, all factory spec. I think this is probably just the decline of the battery. Seems a bit premature, but as long as it doesn't continue to drop it's fine.

Yeah I probably can agree with you might be the battery age , usually not going to get more then 2 to 3 years before needs a replacement.

 

[mark7914]

This is definitely getting worse, rather rapidly. All within the last 3 weeks or so.

Full charge last night, it's 20:50 and it's down to just 20%. I think this is going to have to be returned to the retailer for a repair/rectification - it's only 18 months old.

"Maintenance" gives no clues. Nothing is using more than 0.03% per hour and those apps aren't allowed to run in the background anyway.

What's the best way to evaluate the battery "cleanly" as it were - any app recommendations? Or, maybe, full charge to 100% - turn off WiFi and data - restart the phone - don't touch it or open anything at all and see how long it lasts?

 

[Laura Knotek]

This is definitely getting worse, rather rapidly. All within the last 3 weeks or so.

Full charge last night, it's 20:50 and it's down to just 20%. I think this is going to have to be returned to the retailer for a repair/rectification - it's only 18 months old.

"Maintenance" gives no clues. Nothing is using more than 0.03% per hour and those apps aren't allowed to run in the background anyway.

What's the best way to evaluate the battery "cleanly" as it were - any app recommendations? Or, maybe, full charge to 100% - turn off WiFi and data - restart the phone - don't touch it or open anything at all and see how long it lasts?

If you've been letting the battery drain below 40% regularly, then the battery could be on it's way out, even though it's only 18 months old.

 

[mark7914]

It's relatively unusual for the battery to go below 40%. Normally I'll leave it on the wireless charger in the evenings, and so the normal operating range is between around 50% and 100%.

That's why it's so noticeable that the battery life is dying - numbers this low are really rare.

Half an hour later, now at 14%..

 

[mustang7757]

It's relatively unusual for the battery to go below 40%. Normally I'll leave it on the wireless charger in the evenings, and so the normal operating range is between around 50% and 100%.

That's why it's so noticeable that the battery life is dying - numbers this low are really rare.

Half an hour later, now at 14%..

Monitor it in safe mode
Still happening minister in airplane mode

 

[mark7914]

This is getting worse

So I've installed an app called AccuBattery and it has been gathering statistics.

It shows this:







So, from fully charged last night, down to 68% as at 10:24 AM.

The estimates of how long the battery will last don't seem realistic.

The battery health was initially reported as 86%, it's still gathering data, but that number is falling.

The "mystery icon" using battery is Samsung TouchWiz which I understand is an integral part of the phone/OS and presumably normal - I have never analysed the usage before since I had no need.

OneDrive was opened precisely once: to sync the screen shots to my PC in order to post this.

The "Deep Sleep" data is believable - about 7.5 hours asleep last night (me, not the phone).

In the absence of any other explanation I'm assuming that the battery is beginning to fail and that the rate of failure is not gradual but rather rapid.

Can anyone see anything else of significance?