Broken battery?

[horsie_flites]

I accidentally left my Turnigy 800mAh 20-30c 3s battery plugged into my electronics overnight. I heard that when you use the batteries for too long, it breaks them (the 80% rule). When I try to charge it, my charger displays this warning, the voltage is either too high or too low, in which it is probably too low. Someone once said if I have a programmable charger, I might be able to revive it (but I don't think the one I have is like that). When I plug it in to my voltage alarm, the following voltages appear:

First cell: 2.83

Second cell: 2.87

Third cell: 2.99

All: 8.65

Is this considered broken?

Also, is the battery the only broken thing, or is the ESC and other stuff also damaged?

 

[horsie_flites]

For some reason, when I plug it in now, it charges. Back when I accidentally left it plugged in, it didn't work.

 

[Ricci]

The orher things will be ok

 

[horsie_flites]

Is the battery ok? Or is it still broken? Is it dangerous to use now?

 

[Ricci]

No, is not dangerous. If the charger charges and the balancer balances the cells, everything is fine. I received last week a lipo from HK and it was 10% charged and one cell has 2,7 V Aftee balancing and changing works fine

 

[horsie_flites]

Ok, it just fully charged and seems ok. The cells are balanced.