S21FE screen on time lower than usual.

[CountRavioli]

My galaxy S21FE usually gets 6hrs screen on time with 120HZ mode always on, AOD off, automatic brightness and power saving mode off. For a week now I am getting closer to 5hrs SOT. I was hoping for any insights on what might be causing this issue.

[Saif007_]

You still have 21% left. It will go beyond 6 hrs if you turn on power saving mode

[CountRavioli]

Actually I count my SOT from 100% to 20%. I don't let my phone drop below 20% as its bad for battery longevity.

[Sid_Karna]

In that case, you shouldn't charge your phone to 100 percent either. As per the ones who propagate this idea, both extremes are bad for the battery.

[markwilliam]

Yes but charging battery to 100% once in a week is enough...daily charging to 100% has a negative impact on the battery

[Sid_Karna]

Yes, I too follow something similar. Charges to 100 percent once in a week or two, or when I am traveling.

[markwilliam]

Yes exactly...while traveling i also top it up to 100%

[CountRavioli]

Well charging your phone to 100% isn't as bad as you think. Staying at 100% for extended periods of time is bad. The reason behind not charging your phone to 100% is that your battery will retain an extra 4-5% of its maximum charge capacity after 4 years. But the idea of using your phone as if it has lost 20% of its maximum capacity (if you enable the limit max charge to 80% feature) from day one doesn't make sense to me.

[Sid_Karna]

The science behind below 20 percent use is same as charging to 100 percent.

[CountRavioli]

Well let me give you an example. I used my previous phone for 4 and a half years. I charged it to 100% every time and it retained 86% of its maximum charge capacity after 4 and a half years. Let's say if you limited your phone to charge to 80% you would have about 91% of max charge capacity left after 4 and a half years. Would you feel this difference? No because you don't allow your phone to charge to 100%. I will get more time off the charger after 4 and a half years than you get from day one