My oldest K2 battery (6 years old), has obviously lost one or more cells. During an unloaded voltage check it appears to be fine. Put a load on it, and the voltages plummets to a little over 12V, then starts a gradual decline. With about 2AH left out of 9AH, only available at a voltage lower than desired, it's going to the recycler.

The newer (5 year old) K2 responded pretty well to the discharge - charge - leave it on float for a few days - repeat process. it came back to about 80% of it's original capacity while discharging down to 11.5V.

The take away from this is if you think you may have a LiFePo4 battery issue, a test under load, after a few times through the discharge - charge - leave it on float for a few days - repeat process. will confirm it or fix it.. The old myth that one battery will charge the other battery if you run them in parallel has also been successfully debunked. So go ahead put both batteries on the 12V bus, and you have one less switch to flip in flight,.

SF

We may have set a new record with this topic for actually staying on track. Don't know who is keeping up with this, someone somewhere probably has a graph or two to document what the average number of posts it takes to start arguing about the rules or Flarm stealth mode on a post about a canopy cover.