Help with a Fiat Fiorinno Ev conversion from Micro Vett

Hello everyone.
Mi name is Fernando. Im from Spain, but im living in Norway.
Im trying to help a friend, that have a little cargo Fiat Fiorinno converted from Micro Vett.
The car is from 2012, with a 94V Engine and a Lithium battery pack. Im not sure about the capacity but i can try to find it on the documentation of the car. The owner says that he can make around 80 km in winter time here in Norway ( West side, so from 5 to -5ºc not less ).
To warm the car, is instaled a Diesel Webasto system . Yes, its not so green.
So, The Problem:
The car is not charging the batteryes.

What happened?
He told me, he was driving like a normal working day, and he reach the office with around 25% percent battery left. So he pluged in the car to have it ready for the next day.
The next morning he removed the charging wire, and the outside led indicator was in a fix green light, that means the car is fully charged. ( Blinking orange/red when charging ).
But inside the car, the battery level in the instrumental panel was 25 % yet.
He drove for a while with this battery power until the battery was completly emty... Yes, not a good idea...
After that, the car has been stooped for a long time, and now i has take the chance to try to started again...

What i have done:
Off course, i have been try to plug in the car to see if its was charging, and off course, is not. The same problem, when start to check, it says the battery is full ( according the external information that you can read in the chargers inside the motor compartiment. ) But in the instrument panel, it says is completly empty.
I have checked the battery charger, and it has some rust in one connector, so maybe it was wet for a few time.
The plastic cover that usually mount down the engine in a normal car, is not there, so maybe it was so much water jumping over the charger...

What i think:
1º The charger is not working
or
2º Some problem with some battery cell (3.2v cells i think)

Any other idea?

About the charger:
Its nothing writen on the box, but inside i can read that the motheboard is a Zivan ZR70F, and the box looks like Zivan NG5 ( this one is 230V monophase )
Somebody can tell me how to check this box?, just to confirm if is working property or i must check the batteryes...
I know its possible to check it with the pc, but i have no idea where find the software and how to use it.
Any information will be really appreciated.
Sorry for this boring text...
Thanks so much.