My lifepo4 16 cell 48v battery doesn't get charged

[Avantgarder]

Hi All,

2 years ago I bought from GM the lifepo4 16 cell 48v battery that looks like this one:
http://goldenmotor.com/SMF/index.php?topic=4260.0
It served me for 2 years running for about 16,000km.
Power, efficiency and charging speed are as good as when the battery was new.
Starting from about a month ago I'm experiencing the following problem:

1. I measure 58v on the charger output and 52v on the battery charging input (so far so good).
2. When I connect the charger nothing happens and charger does not charge.
3. I apply a little load on the battery and the charger starts charging.
4. Now I can remove the load and battery is charged till it's full.

Starting from today steps 3-4 do not help and battery does not charge whatsoever.
I do not have a spare charger to verify that the charger is OK.

Questions:
1. Does the behavior described here fit an aging battery ?
2. Does the fact that the performance of the battery is still good after 2 years indicate a good battery ?
3. How can I overcome this charging problem ?


Thanks

[simplyfly]

I think your BMS is out of whack....

[Avantgarder]

New fact that might shed some light :
I found out why yesterday I wasn't able to charge the battery with the trick of applying load on the battery:
Yesterday, for the first time in a while I tried to charge the battery when it was 50% full.
After it was completely empty it could be charged to 100% with no problem whatsoever.