Specifications
The short answer is that a modern battery usually lasts many years, but buying well depends less on the age of the car and more on its actual health. Today there is already an official EU reference for minimum durability, and before closing a purchase it is advisable to ask for specific data on SoH, useful range and charging history.
Quick summary
- As an official EU reference, an electric car must maintain at least 80% capacity up to 5 years or 100,000 km and 72% up to 8 years or 160,000 km, according to Regulation (EU) 2024/1257.
- From 18th August 2024, European regulation requires more documentary traceability of batteries and reinforces that the SoH, the state of health, can be determined from the BMS, the battery management system, according to Regulation (EU) 2023/1542.
- Before buying, always ask for three things: SoH report, proof of real range and some charging history data. Without that, a cheap price can turn out to be expensive.
- Do not confuse gross battery with net or usable battery: the ADAC reminds us that charged energy and truly usable energy are not the same.
- If a used electric car has less usable capacity, the practical decision is not emotional but mathematical: usable range = usable kWh x 100 / real consumption. If that figure covers your routine with a margin, it can still be a good purchase.
- To avoid buying based on an overly optimistic WLTP figure, it is advisable to then compare the car with real range versus WLTP (Available in Spanish) references and with a real range calculator (Available in Spanish).
How many years and kilometres can it really last?
Euro 7 sets minimum battery energy retention for M1 vehicles within its scope: 80% up to 5 years or 100,000 km and 72% up to 8 years or 160,000 km, whichever limit is reached first in each period. It is not a universal warranty for existing used cars. Check measured SoH, the manufacturer's warranty and the applicable approval date.
That means that when looking at a used car, you shouldn't just ask how old it is. The right question is how much usable battery it retains today and whether that capacity still fits your use. For those who make short daily journeys, a certain amount of wear and tear may be irrelevant. For those who travel a lot on motorways, the same level of degradation can significantly change the experience.
| Scenario | Verifiable data or criterion | How to interpret it before signing | Practical decision |
|---|---|---|---|
| Electric car with 5 years or 100,000 km | The EU regulatory reference sets the minimum at 80% capacity | If it is clearly below, do not take it as normal without further technical or commercial context | Demand diagnosis, history and price adjustment or discard |
| Electric car with 8 years or 160,000 km | The EU regulatory reference sets the minimum at 72% capacity | It does not imply that all reach that point, but it serves as a guiding baseline | Check if the usable range still fits your real journeys |
| Car with few years but disappointing range | There may be more difference between WLTP and real use than a serious battery problem | Real degradation must be separated from high consumption due to climate, speed or route | Compare it with a real consumption (Available in Spanish) reference and do a road test |
| Veteran car with correct SoH | Age alone does not invalidate the purchase if the usable capacity is still sufficient | A used electric car can still be very sensible if the use fits | Decide by usable range and price, not by prejudice about the year |
Practical rule: for a used purchase, mileage matters less than the combination of measured SoH, real range, charging history and the model's thermal management.
What degradation means and when you should be concerned
Degradation does not mean that the car will stop working, but that the battery loses usable capacity, i.e. the energy actually available to power the car. If a battery delivered 60 usable kWh and now delivers 54 usable kWh, it retains 90% SoH. That SoH is much more useful than just talking about years because it connects directly to the range and your daily use.
The important thing is not an isolated figure, but the practical effect. A car with 90% SoH is usually still a very reasonable purchase. One with a lower value may still be suitable for city or short journeys, but it requires an honest assessment of whether it meets your needs. If the car is operating near 72% with moderate age or mileage, it's time to ask for explanations and proof.
Usable capacity, net battery, and gross battery are not the same
When comparing specifications or advertisements, look at the net battery or usable, not just the gross. The gross battery is the total installed energy; the usable is what the car allows to be used to protect the cells and extend their life. This difference matters a lot when you try to translate a technical specification into real-world kilometres.
The ADAC gives a very clear example: in their measurement, a BMW iX needed 109.3 kWh to fill a battery with 94.8 kWh net. This includes charging losses and protection margins. That's why it's not advisable to draw quick conclusions by looking at a single figure.
What factors accelerate or slow down wear
- Temperature: sustained heat and intense cold are more damaging than a temperate climate.
- Typical SoC: SoC means state of charge. Spending many hours at 100% or very discharged is usually worse than operating in an intermediate zone.
- Rapid DC charging: using it occasionally is not a problem; making it an intensive routine can accelerate wear.
- Thermal management: a system that effectively controls cell temperature usually helps preserve the battery better.
- Type of use: frequent long journeys, always sleeping at 100%, or mainly using the car in the city do not cause the same wear.
The good news is that the ADAC considers a long battery life realistic thanks to the role of the BMS, which monitors temperature, voltage, and cell balance. If you want to delve deeper into health and degradation, this QuantumDrive guide on lithium batteries, health, and degradation (Available in Spanish) may also help you.
QuantumDrive plans your route considering your real conditions.
Discover your optimal route taking into account charging points and your real range.
What signs to check before buying a used electric car?
The truly useful signs are few and specific. First, ask for the SoH or an equivalent report. Second, compare the car's real range with what is reasonable for that model and use. Third, check if the history suggests intensive rapid charging, long periods at 100%, or very demanding use in hot conditions. If one of these three points fails, the purchase warrants a second review.
From 18 August 2024, Regulation (EU) 2023/1542 reinforces the obligation to accompany certain batteries with documentation on performance and durability. Furthermore, it provides that the user or a third party can determine the state of health and expected life from the BMS. In second-hand purchases, this provides a much better basis for demanding proof.
Signs of a healthy purchase versus warning signs
- Good sign: Documented SoH consistent with age, use, and mileage.
- Good sign: Credible real range on motorways and in the city, not just an optimistic figure from the dashboard.
- Good sign: Clear maintenance, campaign, and update history.
- Alert: Large differences between the expected range and what the car achieves on normal journeys.
- Alert: Seller avoids providing diagnostics, BMS screenshots, or a long test drive.
- Alert: Sudden drops in percentage over a few kilometres or an anomalous end of charge without explanation.
How to check if the real range fits your case
It's not enough to see if the car shows many kilometres at 100%. You need to translate its usable battery to your real use. The simple formula is this: approximate usable range = usable kWh available x 100 / real consumption in kWh/100 km. If the car retains 50 usable kWh and your motorway use is around 18 kWh/100 km, the indicative range will be 50 x 100 / 18 = 278 km. If you want to arrive with a 10% margin, the practical distance drops to about 250 km.
This calculation is more useful than any vague promise. If you also want to adjust better for temperature, speed, or journey profile, it's advisable to cross-reference it with a real range calculator (Available in Spanish) or with this explanation about differences between WLTP and real use (Available in Spanish).
An independent battery test makes sense in sales
If the seller does not provide a reliable report, paying for an external test usually pays off. The ADAC itself mentions the use of independent SoH verifications in buying and selling operations. There's no need to chase the perfect figure; it's about reducing uncertainty before signing.
What data to ask the seller and how to interpret it
If you're going to see a car, don't settle for “the battery is fine”. Ask for SoH, estimated usable capacity, 100% range, charging history if available, and a sufficiently long test drive. With that, you can make a much better decision than with the car's age or a photo of the dashboard.
The simple rule is this: if the SoH is aligned with the mileage, the real-world range matches the car type, and there are no strange charging or discharging behaviours, the purchase is probably sound. If the SoH is opaque or the range drops too quickly, you need to negotiate very hard or walk away.
| Data to review | What it tells you about the battery | Reasonable signal | What to do if it doesn't add up |
|---|---|---|---|
| SoH or State of Health | How much usable capacity it retains compared to when it was new | Documented figure consistent with age, use, and mileage | Request independent test or put the operation on hold |
| Usable or net capacity | The energy actually available for driving | Clear data, not confused with gross capacity | Recalculate real-world range before assessing the price |
| Real-world range in use | How the car performs outside the lab and WLTP | No major deviations on comparable journeys | Take a long test drive and compare with consumption benchmarks |
| Charging history | Whether the car has mostly relied on slow charging or intensive rapid charging | Mixed use without a constant extreme pattern | Assess potential greater wear and review the price |
| Percentage behaviour | If the BMS estimate seems stable and consistent | Progressive decline, without strange jumps | Review diagnosis more thoroughly and don't close the deal hastily |
| Charging speed according to SoC | How the battery responds at different charge levels | Logical curve: more power at the beginning and a drop as it approaches full | Look for possible misalignment, thermal limitation, or greater wear than expected |
Key idea: the BMS is the most useful source for understanding health and expected life. European regulatory direction is precisely towards this measurable traceability from the vehicle itself, as explained by the JRC and Regulation (EU) 2023/1542.
Once you have this data, the next step is no longer theoretical: check if the remaining range fits your journeys. For this, it helps a lot to compare the car with a real-world consumption (Available in Spanish) benchmark and with planning based on real conditions, not just the advertised WLTP figure.
How much does a battery cost and when does it make sense to consider replacement?
It's not advisable to buy a used electric car thinking about changing the battery from day one. In most cases, it won't be necessary for many years. The right question isn't "how much does a battery cost?" but "how much usable range does this car still give me for my use?". If it still covers your journeys with a margin, replacement isn't an immediate issue.
Even so, this section should help you make decisions with numbers. Since the price of a complete battery varies greatly depending on size, architecture, brand, and availability, it doesn't make sense to give a single figure. What's useful is to calculate the total cost of ownership of the car you're considering and compare it with a better-maintained alternative.
Mini formula to decide if wear is compensated by price
You can use this simple rule: real purchase cost = car price + foreseeable short-term repairs + risk margin for battery uncertainty. If two similar cars cost 18,000 and 20,000 euros, but the 18,000 euro one doesn't provide SoH or clear proof, and you estimate a reasonable risk of 2,500 euros between diagnosis, possible repair, and lower future value, its real cost approaches 20,500 euros. In that scenario, the more expensive but transparent car might be the better buy.
You can also convert it to usable kilometres. If one car retains 52 kWh usable and another 46 kWh, with a real consumption of 17 kWh/100 km, the theoretical range difference is 306 km versus 271 km. That's about 35 km of margin per charge. In urban use, it might not matter; on motorways or for recurrent journeys, it can significantly change the experience.
When degradation stops being a nuance and becomes a problem
- When the real-world range no longer covers your daily use without inconvenient extra charges.
- When the car falls far below what's expected for its age and mileage, and there's no clear explanation.
- When rapid charging shows strange or excessively poor behaviour for the car type.
- When there isn't enough traceability to know what you're buying.
On a journey, it's not just about how much battery is left, but also how it charges
Charging curve means how the charging power varies as the battery percentage increases. A car might have slightly less usable capacity and still travel well if it maintains a healthy curve in the low and mid-range. Conversely, a car with a good usable battery but poor on-road charging can be more inconvenient.
If your doubt is whether a somewhat degraded battery will still be suitable for journeys, it's also worth reviewing how rapid charging influences long trips and why it's not always worth charging to full. This QuantumDrive guide on how to optimise rapid charging on long journeys (Available in Spanish) might help you with that.
What decision is usually sensible depending on the battery's condition
The most useful way to conclude this analysis is to distil it into a simple decision. If the car maintains a solid SoH, it offers enough range for your routine and comes with traceable information, so the battery shouldn't hold you back. If the health data is missing or the actual performance doesn't add up, don't buy blind, even if the price seems attractive.
Quick decision rule
- Buy with peace of mind: Clear SoH, consistent range, stable charging and a reasonable price.
- Only buy if you adjust the price: a bit more degradation, but suitable use and sufficient documentation.
- Best to pass: no battery report, dubious range, sudden percentage drops or opaque history.
If you're still comparing several options, it might also help to check our guide on how to better choose your electric car before buying (Available in Spanish). It's a good follow-up for organising criteria once you've cleared up any battery doubts.
Related reads to help you decide better
Real-world range versus WLTP (Available in Spanish)
Helps you separate actual degradation from overly optimistic expectations in the spec sheet or advert.
Real-world range calculator (Available in Spanish)
Used to translate the car's remaining usable battery into actual usable kilometres based on your consumption.
Health and degradation of lithium batteries (Available in Spanish)
Expands on what factors accelerate wear and how to better interpret battery health.
Frequently asked questions about battery life
How many years does an electric car battery last?
Euro 7 sets minimum battery energy retention for M1 vehicles within its scope: 80% up to 5 years or 100,000 km and 72% up to 8 years or 160,000 km, whichever limit is reached first in each period. It is not a universal warranty for existing used cars. Check measured SoH, the manufacturer's warranty and the applicable approval date.
How many kilometres can an electric car battery last?
The useful regulatory reference is 100,000 km and 160,000 km with the cited capacity thresholds. For purchase purposes, the important thing is not to chase a theoretical maximum figure, but to confirm how much useful capacity it retains today and what real-world range it still delivers.
Is it normal for the battery to lose range over time?
Yes. All batteries degrade with age and cycles, but that doesn't imply a fault. The correct question is whether that loss already affects your daily commutes or your journeys. If it doesn't change your usage, it can still be a perfectly sensible purchase.
What SoH should I accept before buying a used electric car?
There's no single universal threshold because it depends on the price and your usage. A high SoH gives more leeway and better future value, but a car with less health can still be worthwhile if the price reflects it and its usable range is sufficient for you. The key is not to buy without measured data.
Does rapid charging damage the battery much?
Not from occasional use. The problem usually arises from making it an intensive routine, especially with unfavourable temperatures and long periods at 100%. Thermal management and the BMS are crucial for limiting this wear.
Can I ask for a battery health certificate before buying?
Yes, and in fact, it's one of the best possible decisions. European regulations reinforce performance traceability, and the BMS allows for determining SoH and expected life. If the seller doesn't provide a reliable report, it's worth requesting an independent test before signing.
Is it worth buying an electric car with some degradation?
Yes, if the real-world range still fits your routine and the price reflects that wear. A battery doesn't have to be perfect to be a good purchase. The important thing is that the car still covers your journeys with margin and that the health status is documented.
Start planning your routes with QuantumDrive.
Discover your optimal route taking into account charging points and your real-world range.
What to remember before signing
An electric car battery isn't well evaluated with a generic question about how long it lasts. It's evaluated with four pieces: usable capacity, SoH, real-world range and traceability. If those four fit, the purchase can be very good even with years and kilometres on it.
And when you want to take that decision into practical terms — whether you'll reach your destination with margin, how much a somewhat degraded battery penalises you, or how many stops you'll actually need — it's sensible to check it with tools and references based on real-world conditions.
Euro 7 sets minimum battery energy retention for M1 vehicles within its scope: 80% up to 5 years or 100,000 km and 72% up to 8 years or 160,000 km, whichever limit is reached first in each period. It is not a universal warranty for existing used cars. Check measured SoH, the manufacturer's warranty and the applicable approval date.