Well I just had to be an idiot and went against my better judgement and did what dji recommends on one of my battery's that had 20 charge cycles on it and so I did the deep discharge thing that dji recommends even tho they nore any one else can come up with any reason for it. and any ones guesses are just that just guesses as to why its good to do. Tho none of them are very good guess considering they have no validity to them.
WELL lets just say it turned out to be very very very bad idea and it destroyed my otherwise perfectly good battery. That only had 20 charges on it prior. and considering that they cost about $150 thats about $7+ per flight and actually even more considering that I also did the 10 flights break in on the battery to so they were not even real full flights.
Here is what happened. I noticed the battery info was saying it had 20 charges on it. So when I was done flying I let it hover till it was at 8% and then I landed it and shut it off. (was at 7% by the time I landed and got it shut off. I then took the battery inside and let it sit for about 1/2 hour to cool down so I could charge it. I waited till it was cool and plugged it in to the charger and Went to do some other stuff while I was waiting and after about 1/2 hour had gone by that only the first led was blinking as it was charging which seemed very odd that it was still under 25% done. So I let it go some more and its still never went above the first led. and thats when I also noticed the smell of hot electronics. So I picked up the battery to see if it was the battery that I was smelling and as soon as I touched it the top was burning hot and starting to melt. WOW thats not good. So I unplugged it for about an hour and when it was cool to the touch. I tried again. and it started getting hot again with in the first min or so. But it did not seem as hot as before so I let it go while keeping a close eye on it and then after 2 more hours it still was not past the first led. So I popped the battery in the p3 and looked at the battery info. It was at 17% charge even after a few hours charging. my cells were all the same cell volts. and it said the battery was at 100% health. HUM ok now thats weird. But i thought ok maybe after a deep discharge and charge cycle that maybe it just charges real slow or some thing. So back on the charger it went then after about 3 or 4 more hours i noticed its now made it to 2 leds blinking as it was charging. Then it went a few more hours and got to the 3rd led. Woot hoo im thinking ok its charging just real real slow. Then about an hour later i noticed the leds would blink on in secession with each other then they would turn off along with the red led in the power button then It would come back on a few seconds later and then do the same thing over and over. So now Im thinking oh my charger must be of crapped out.. So I swapped it over to my other charger and its still doing it and I also checked the volts on the other charger and it was fine so that rules the chargers out. Then I unplugged the battery and waited a bit and tried to charge it some more and got the thing were it was still turning its self on and shutting off over and over. So I poped in the p3 and looked at the info it was at 58% charge and just would not go any higher even when I let it go over night on the charger it was still at 58% in the morning. So I then decided to put it the p3 and tried to see If I could run it down to 8% and try it all over again.. Took about 8 mins to drain it. Then when went to charge it again I was right back to square one. and after about 12 hours it was at the 3rd led again and then started the shutting off and starting thing again and when I poped it in the p3 to see what the info said it was back at 58% and just would not go any higher.
So basically doing what dji said to do toasted my battery that was fine before doing the deep cycle discharge.. Well lets just say I will never be doing that stunt ever again. Tho I know why they would want someone to ruin there $159 battery after the first 20 charges........ So that you can bust out another 159 and buy a new one OR deal with the nightmare of an ordeal to try and get dji to honor any warranty or wait weeks for them to send a new one.
Sounds like you had cells short out.....discharging did not cause that problem......if you don't discharge then to around 10% on a regular basis you will need to deep discharge them every now and then so they will take a full charge......I choose to not charge till 10% if possible....also on the app you can look at the individual cells of the battery.....if one is considerably lower than the rest you have a problem......the battery might show it has a charge but the low cell could short to another cell or drain faster than the others which can cause cause a catastrophic failure if you are in flight.....I just ran one down to 6% and another to 7% yesterday and they charged fine....not a good idea to leave these types of batteries on a charger over night.....if a cell shorts to another while charging it can cause a fire as you almost saw