batteryFiat 500e high voltage battery regeneration – after unprofessional rise of overdischarge in another service.
The history of this repair began with a typical problem: Fiat 500e does not load and does not start after a long time of not using the car. From the initial interview, I learned that the car could stand in this condition for several months. Therefore, we immediately started disassembling the HV battery…
An additional problem that came to light after dismantling the battery, was broken warranty seals. So the battery has already been repaired before and as I checked, not by me. At this point, I began to anticipate the potential source of the problem. Everything was confirmed several minutes later, after removing the top cover of the Fiat 500e’s battery pack. Photos of voltage measurements on 4 front, six-cell battery modules speak for themselves.
Initial measurements showed that most of the batteries hold current quite well, a few cells were below the lower threshold of the on-board charger, which is below 2.7V per cell, but not less than 2.0V. On the other hand, the entire six-cell module, on the very front of the battery, with marked cathodes (+) and anodes (-) of the cells. In addition, with the same marker, a great number one. I checked the serial numbers of the battery modules and ruled out that the module was replaced with another battery.
This is the best proof that an overly discharged Lithium-Ion battery is not enough to simply “charge”. Connecting such cells to a 6-cell RC-modeler charger or home “laboratory” bench power supplies gives an excellent chance for a permanent and clear deterioration of the health of Lithium batteries until they are completely damaged.
Unprofessional attempts to excite or regenerate the Fiat 500e high-voltage battery in most cases end in damage to the insulators between the cathode and the anode of the cell. Such a cell will lose a dozen or so mV of voltage every day, and thus, causing progressive unbalance of the HV battery.
In this case, the state of the module with number one gives no chance to save it and we have to replace it with another recovery module. At this point, it is impossible not to mention that it is not enough to take the first module from the edge, “as long as the plus is on the same side”. The replaced module must be matched in terms of age and battery capacity, and thus: “raid”.
Thanks to this, we are sure that the installed modules will not stand out from the rest of the high-voltage battery of the Fiat 500e, causing its constant balancing, i.e. heating and wasting energy.
Fiat 500e high voltage battery regeneration. Is this the end of the job?
I am convinced that most websites end their work at this point. The car has already started, it means “you can cancel the payment and everything else is invalid.” Meanwhile, at FiatService.EU, after the first full cycle of the battery, it’s only time to perform real tests of the battery at full load and in the full operating range. Thanks to this, even if the customer does not accept the cost of further repair, aimed at improving the performance and range of the car. I am the one who is sure that the high voltage battery of your Fiat 500e is safe and will not be a “ticking surprise” or simply a BOMB.
Fiat 500e battery regeneration is a service that you should not entrust to anyone other than FiatService.EU.
See the results of the power test after excitation of the high-voltage battery on our FiatService.EU youtube chanel.
