My first ever car.
This project all started when a colleague showed me a link of this car for sale. It was non functional and thus quite cheap. And me being interested in electronics obviously had no choice but to buy it:)

The car in question was a Micro-Vett Fiorino. Actually a Fiat but converted by the company Micro-Vett to electric. They converted these vehicles from 2007 to 2012 when they went bankrupt.

Being such early electric vehicles they had a few teething problems. Specifically with battery management and drive inverter instabilities.

The same was true for my car. The battery was completely out of balance and some cells deep discharged. The previous owner tried to fix it but ultimately gave up, and I bought the car with the batteries half disassembled on a pallet in the trunk! It was also missing the onboard charger and various wiring.

Fixing this car properly meant not only manually balancing the battery, but also preventing future failures. Given that the cells were discharged at different levels and being mismanaged for so long I expected the cells to have different wear rates. Thus I decided to go through the tedious process of measuring the capacities of all cells and reorganizing the parallel/series connections to make sure minimal imbalance would occur during a discharge cycle. This all in all took a month or two.

To prevent future failures I installed a separate BMS with more balancing capacity and better monitoring.

When that was finally done, I had to find a suitable charger for the car. But the company being bankrupt and little to no parts used available I decided to use a different charger than original. To integrate it properly into the car I made a custom controller based on ESP32 as a bridge between the charger and car.