Among the arguments often used against electric cars, there is the one concerning the short duration of lithium batteries for the automotive sector, and related “disposal“. In quotation marks since we have now learned that these accumulators, between second life and recycling, do not need to be disposed of.
Among the various versions of the unverified news, electric car batteries are expected to last 6, 8 or 10 years. There are for today a good number of electric cars of the first generation which have already reached this age, and can therefore offer us real numbers with instrumental measurements.
As in the case of the Renault Zoe Q210, the first to arrive on the market in the now distant 2013, and rather widespread in Italy, especially shortly after, since 2014. Just this year the car subject of our test. It has long been used as an everyday vehicle, covering almost 80,000 km so far. Not a huge figure, but still enough for a reliable measurement.
To measure the residual capacity, an OBD2 socket reader is used, capable of reading the data directly from the vehicle’s Can Bus and sending them to an app that can translate them via Bluetooth. In the specific case it is a Konnwei device and the Android app called CanZE. As seen from the image above, the “health” of the battery by 90%, a rather good figure which indicates that at present the battery cells still have a capacity of 90% compared to the nominal value when new.
The measurement was made with the car at 90% charge, i.e. with 16.8 kWh available and 2.5 kWh at full charge, thus bringing the overall residual value at 19.3 kWh, against about 22 kWh from new. There is indeed a slight deviation in this data, but it could be due to often inaccurate nominal values and within a tolerance limit. The battery obviously maintains a voltage of almost 400 V, and the available charging power would be 51 kW, despite the 10 degrees Celsius temperature of the cells, a value that the car would not reach anyway, as the on-board charger stops. to 43 kW.
One last interesting fact that can be discovered is related to the voltage of the single cells, which appears quite aligned. There are only 4 elements (last two rows of boxes) which appear slightly lower, but with values however not alarming.
Ultimately it can be considered that the conditions are more than fair given the age and wear, e certainly not a battery that would need an imminent changedespite the chemistry of 8 years ago. In terms of composition, the cells have further improved over the years, and ensure more performance and less deterioration, as well as being obviously with greater capacity. This factor allows to “dilute” the recharge stress on more cells or on a greater capacity, and therefore decrease the degradation. We will try to carry out more measurements on more models, and with different ages.
– .
