james_bl2003

I have a question?????? So I was out bashing my emaxx kinda doing a no no I was running Two 2s turnigys with no low voltage alarms or cut offs I stopped when the truck first showed a drop in speed. When I went to pull the batteries one was puffed but it was only warm to the touch not hot, and the other was still cold. I checked the voltage when I waited for it to un puff and the puffed one shows 3.16 and the other shows 7.11

So my question is ....... Is the puffed one junk now??? And why is their such a difference in voltage between them.

I'm new to Lipos so any info is helpfull. I'm running a dual 700 ho kershaw motors with the stock evx2 speed controller.

t9dragon

My Feedback: (11)

Yes, it is basiclly toasted. I wouldn't even try charging it.

james_bl2003

So why the big difference in voltage between the two. That's what I don't understand. Neither battery is very old at all.

t9dragon

My Feedback: (11)

So the voltage of one cell was 3.16 and the other cell was 7.11. Each cell in a 2s lipo is 3.7v add them together and you have 7.4v. A fully charged lipo should read 4.21.

james_bl2003

no that was the voltage on two seperate packs not the individual cells on the puffed one. I don't know if my charger will let me check each cell. I have a duratrax onyx 245 dual charger.

guver

My Feedback: (325)

Your low pack ran empty (much too low a voltage) before the other one.

masterhacker1989

you need a lvc to run lipos, also I recommend buying a balancing charger. I would throw em both away and get 2 new packs, also dont even attempt to charge the puffed pack (unless you want to risk it starting on fire)

steed2-inactive

yep take that low pack and toss it in a bucket of salt water for 24 hrs. its in a very dangerous state right now. once lipos start to discharge at a certain point the discharge becomes exponential and drops fast. the reason one was so much lower than the other , well hard to say, it may have been a slightly weaker pack and took most of the load.