Saturday, December 6, 2014

Oh Crap

Since it had been a while since I checked on all the vehicles I thought I would check charge on the car and other projects. I turned on the Mazda and... NOTHING, not a good feeling.
The batteries were all at less than 1 volt, I assumed I had destroyed the battery pack.
I put the plugged in the charger and the voltage came up to 2.5v a cell quickly.
I charged for 10 hours at about 8 amps, so far the voltages are very close and holding, I have yet to take it for a test drive and check the capacity.
I wanted to bottom balance the pack, but not like THIS! I am not holding much faith that the pack is good as the voltage is never supposed to go under 2.5v a cell.
The lesson learned, even though I had good intentions on checking the charge, I should have disconnected the pack. 
I guess I will find out if you can fully deplete a Lithium battery and bring it back to life.


  1. Jerry,

    Hopefully if the cells were all reading 1 volt, none of them reversed polarity. If that is the case, I am betting you will be ok. Did you find out what was draining your pack as you want to make sure and correct that problem so it doesn't happen again. I am using an IOTA DC-DC converter with a small lead acid battery for the 12 volt system, so I can just unplug the DC-DC converter from the pack and plug it into a 120 volt outlet when the car is not being used much.


    1. Randy,
      It was my Iota DC/DC keeping my 12v battery charged. I usually break the connection if stored but didn't this time. I got it charged to 175V and disconnected the pack and will measure them after they sit for a bit.