samsung galaxy s5 battery drain when phone is shutdown

[mikeos1]

I recently got a Samsung S5 on the advice of a professional friend who said it was the best phone Samsung have made. However I'm puzzled how it loses battery power so rapidly, even when the phone is powered off and shut down. As an example, I charged the battery last night to 100% and shut it down. 12 hours later, powered it on to find the battery now shows 46% with absolutely no activity at all. How is this possible please? Any advice welcomed.

Mike

 

[methodman89]

I had an S5, and the easiest way to diagnose your problem is to get a new Samsung battery, which if you are using the original battery still, is most likely the problem. It is easy to do. Or, go to Settings, Battery, and look at what used your power.

 

[Rukbat]

I agree - losing power with the phone off is a pretty sure sign of a dead battery. If you want to confirm it, charge it to 100% tonight, then take the battery out, Tomorrow, put the battery back in and it should be down to about 55% or so.

How? A partial short inside the battery would do it (and that's one of the major problems with lithium batteries). Also a battery that's been mistreated and is just (figuratively) exhausted would do it. All batteries self-discharge (which is why a lot of non-rechargeable batteries have a "use by" date), but a good lithium battery shouldn't discharge by even 1% in 12 hours of not being used. (And you won't see a 0.2% discharge - it goes by whole numbers.) A whole new battery is only about $10, so it's not that big a problem. (The seller probably just got used to it.)