Warm battery when not even plugged in?

[Shockabilly]

Hi all...my wife has a Haibike with a Bosch 500 Powerpak & for reasons I fail to understand, the battery is warm to the tech at the lower end of the casing, this is when its off the bike & stored, so in effect not being used or charged etc. Anyone else out there with this issue?

 

[Stihldog]

Hi all...my wife has a Haibike with a Bosch 500 Powerpak & for reasons I fail to understand, the battery is warm to the tech at the lower end of the casing, this is when its off the bike & stored, so in effect not being used or charged etc. Anyone else out there with this issue?

I have two Power Fly 5 with the 500w Bosch gen4. They are both room temperature when stored or installed and not used.
I would be a little concerned. Sounds like some or one of the cell(s) is trying to discharge.
Of course keep the battery in a safe place until you figure this out. You can see the spacer used for the 500w battery.

 

[Shockabilly]

I would put it outside... right now. ?

Agreed & its already been relocated outside! It's still under warranty so a call to the bike shop will be made first thing on Monday morning.