[AC Question]

it charges up to 80 or 85%, then stops charging, but if i unplug and re-plug the charger it charges up to 100% at normal rate.

[daddyd302]

I would return it right away.

[ClintRo]

^^^^ this

[Wopback]

What brand charger are you using? Im assuming its the OEM charger.

Agree with above, exchange it!

[jcp007]

+1 Return it.

[touama]

Samsung's reply on this issue :
This mail is in regard to your Samsung handset S8.

We would like to inform you that; this is not an issue with the device, this is the inbuilt feature of the handset, during

*Wireless charging or fast charging, the device may feel hotter and this is normal range of operation which does not affect the device’s lifespan/ performance.

If the battery temperature goes beyond specified limit, the charger may stop charging the device and start charging again once temperature goes down upto the normal temperature (e.g. 36ºC) and this is only a precautionary action for customer safety. This mode is called as*“Swelling Prevention Mode”.

Swelling prevention mode is triggered due to the high temperature. If the phone temperature rises beyond certain limit, the maximum charging voltage is limited to 4.15V which is equivalent to 70~80% (±*5%) of battery level. This operation is disabled and starts charging again once temperature goes down up to the normal temperature (e.g. 36ºC)

[F_Benitez]

I've been having the same experience with the Samsung OEM wireless charger that was "inherited" to my S8+ from my S7 Edge. Since about a week ago (after a couple months ownership) all of a sudden, it stopped charging at around 80%. Noticed it was kinda hot too.
I would "top it off" with the regular wall charger and assumed it was something to do with compatibility with the previous gen charger. The above post explains a lot. I'll stick to the wall charger for now. Hope I can go back to wireless and somehow circumvent this heat issue.