Since battery replacement is an expensive pleasure, the warranty period offered by manufacturers is quite clear about what they themselves expect when evaluating the reliability of batteries. Major electric car manufacturers, such as Ford, Volkswagen or the companies of the Stellantis group, usually provide an 8-year warranty for batteries. In other words, the source of electricity should not be a concern for at least this time.
“The total practice in the market is 8 years and 160 thousand. kilometers traveled. Some manufacturers may offer more. For example, Rivian in the US provides 280,000 km warranty, but for the same eight years. This is probably related to the longer distances driven in this region,” says Tadas Ratkevičius, electric car expert and founder of the platforms bestev4me.eu and evtest.lt.
Shouldn’t be a concern for at least a decade
Modern lithium-ion batteries, which are mostly used in electric cars, are quite reliable and long-lasting, so they should serve faithfully for at least a decade. A significant number of manufacturers are also developing technologies for the secondary use of batteries in parallel with their main activities and are finding areas where batteries removed from cars due to deteriorated characteristics can still serve perfectly as energy accumulators.
For example, if the electric SUV “Ford Mustang Mach-e”, which is quite popular in Lithuania due to its less than 50,000 EUR price (for companies this means not only a subsidy, but also a VAT deduction), a battery with a useful capacity of 91 kWh would wear out by a third after a decade, the remaining 60.7 kWh would still be enough to meet the needs of a medium-sized family living in a detached house for several days.
However, more than one study shows that the capabilities of batteries are much greater. The US Department of Energy predicts that today’s electric car batteries will last well beyond their warranty periods. In countries with a moderate climate, they should not cause any problems for 12-15 years. In countries with a more extreme climate, they are expected to have a smooth service life of at least 8-12 years.
What is special about lithium-ion batteries?
Lithium-ion batteries have a higher energy density than, for example, the nickel metal hydride batteries often found in households. This means more power can be packed into a smaller package. Another advantage of a lithium-ion battery is that it maintains a more even charging voltage.
The list of disadvantages of lithium-ion batteries includes the high price and the problematic extraction of the materials needed to create such a battery from an ecological and human rights point of view. Extracting cobalt and nickel is energy-intensive, and mines in certain countries (for example, the Democratic Republic of the Congo) have raised questions about their work ethics.
“Lithium iron phosphate (LFP) batteries are now being used more widely. Their properties are better because they can be charged up to 100%. They undergo more charge and discharge cycles and self-discharge more slowly. However, their density is lower, so in order to have the same kilowatt-hours, you will have to choose larger and heavier batteries,” explains T. Ratkevičius.
According to the expert, many are waiting for a breakthrough in sodium-ion battery technology, which would not require so many expensive fossil metals and would be much cheaper. However, their density is also significantly lower.
“But for those models that don’t need to drive far, they can be a good, inexpensive option,” says the interviewer.
What causes battery wear?
The longevity of lithium-ion batteries is probably largely determined by usage habits. Batteries that are constantly being fully charged and discharged wear out faster, and it is not very healthy for such batteries to be charged frequently at high speed.
For example, the battery of the Ford Explorer SUV, which can travel 602 kilometers on a single charge, can be charged at a rate of up to 185 kW, so the energy reserves at direct current fast charging stations can be increased from 10 to 80 percent. can be refilled in 25 min. However, experts advise to use fast charging only when you really need it – on long trips, etc.
“Wear depends not so much on the kilometers covered or the age, but on how the batteries are operated. For example, the faster they are charged, the more often temperature spikes occur. If the battery does not have an active cooling system, problems arise. It is especially important to charge lithium-ion batteries as slowly and for as long as possible and not to charge them to 100 percent,” recommends T. Ratkevičius.
The most favorable temperature for lithium-ion batteries has been found to be between 10 and 29 degrees Celsius. The interviewer also points out that extremely low temperatures do not have such a bad effect on electric cars as high temperatures.
“If the electric car is imported from the southern regions, where it was often parked outside, this is already a signal that the condition of the battery should be checked. Because when the car heats up in the sun, so does the battery, and if this happens continuously, it can shorten the life of the battery. Therefore, it is better to store electric cars in the shade or avoid large temperature differences,” recommends the specialist.
For people looking to ensure battery longevity, Ford experts also advise using digital services. For example, owners of electric cars of this brand can remotely set the desired time of departure through the FordPass app, and the electric car itself will heat the cabin using energy from the network instead of the battery. The app can also remotely monitor the charging status of the electric car.
It is also important that the warranty applies not only to the elimination of faults, but also to the degradation of the battery. This is the name given to the process when the battery wears out and as a result its technical characteristics deteriorate – for example, the useful capacity is lost. Most often, manufacturers provide a guarantee that the battery will save at least 70% of its charge during the aforementioned 8-year period. its original capacity.
“Some manufacturers guarantee that battery degradation will not exceed a certain level and promise to restore the battery’s capacity to that level if, however, it degrades more. Some manufacturers even replace the battery itself. But this kind of behavior was more common at the dawn of electric cars, and now batteries have become more reliable,” notes T. Ratkevičius.
Here is a study conducted by Tesla owners in the Netherlands, which showed that the battery packs installed in Model S sedans degraded on average by about 5 percent. during the first 75 thousand kilometers driven. This curve becomes steeper as the number of kilometers increases: after driving more than 220 thousand. kilometers, electric cars still maintained at least 90 percent. original capacity.
Another important factor is that batteries (like all other electrical components) are subject to the highest safety standards in Europe or the US. Electric car batteries must be installed in a specially protected sealed frame, and before production must withstand a series of tests involving heavy overloads, extreme temperatures, fires, crash simulations, water immersion, vibrations and short circuits.
The high-voltage wires of electric cars are additionally insulated, and cars are equipped with a special circuit breaker that allows you to turn off the entire electrical system with one click.
For security and convenience, experts advise not to forget to update the software. In the most modern electric cars, such as the aforementioned Mustang Mach-e or Explorer, the software can be updated online.
Tags: Reliability electric car batteries years driver worry wear tear
