SOH simulator · Renault Zoé 52 kWh (ZE50)
90%
Estimated between 85% and 95% · Excellent
At least 15 points above the warranty threshold
Manufacturers guarantee that a battery keeps at least 70% of its capacity, most often for 8 years or 160,000 km. For this model, at this age and mileage, the battery is well clear of it.
RangeEstimated range: 340 to 375 km (new: 395 km WLTP)
The light band is the range.
The dot is this car today.
The range a buyer expects for this model.
Calculation details
A battery loses capacity quickly in its first two years, then slowly. The estimate adds up four kinds of wear, each calibrated on published measurements:
- Early drop
- 3.5 pt
- Slow wear, sped up by fast charging
- 4.3 pt
- Wear from mileage
- 1.8 pt
- Heat
- 0.0 pt
- Estimated SOH (centre)
- 90.3%
The first three are multiplied by a factor specific to the battery version: 1 for the average of the measured fleet, less for batteries that wear more slowly. For this version, it is 1.2. Heat adds up each year (0.4 point a year in a hot climate). Cold has no effect in the calculation: we found no measurement that quantifies it. The range is the estimate plus or minus 4.9 points: it widens with age, because two cars of the same model can differ by 13.5 points (Aviloo), and beyond 150,000 km by one point per 25,000 km: published measurements stop there, and heavily driven Teslas with NCA or NMC batteries are more worn than the estimate.
Up to today, the curve follows this car's average mileage (its mileage divided by its age), so it goes through the dot. After that, dotted, it follows the yearly mileage chosen under the curve. That choice does not change today's range, only what comes next.
The word on the gauge reads off the central estimate: excellent from 90%, very good from 85%, good from 80%, fair from 75%. For reference, batteries measured by Aviloo at 150,000 km sit between 86.7 and 94% depending on the model.
For the Dacia Spring, MG4, Fiat 500e, Smart EQ, Kangoo, Mégane E-Tech and e-2008, we found no solid published measurement: their estimate follows the fleet average or their battery family.
The check. Compared with 22 used EV listings that published a measured SOH (survey of 23 October 2026), the estimate is 3.4 points off on average, and the listed SOH falls within the range 14 times out of 22. Compared with Aviloo's medians for nine models, it is 2 points off at most.
Its limit. Most published measurements come from companies that sell battery certificates, and an SOH written in a listing is declared by the seller. Geotab, which sells no certificate, measures an average loss of 2.3 points a year: our estimate leans optimistic.
Sources
- Geotab, 22,700 vehicles tracked (13 January 2026): shape of wear, effect of fast charging and heat.
- Aviloo, via Electrek, 500,000 tests (3 September 2026): medians per model at 50,000, 100,000 and 150,000 km.
- MyBatteryHealth, 80,855 diagnostics (21 July 2026): average SOH by mileage band.
- Arval, cited by Avere-France, 8,300 certificates (July 2025).
- Older air-cooled batteries: a 2018 New Zealand study (Nissan Leaf 24 and 30 kWh) and Moba (Peugeot iOn, Citroën C-Zero, Mitsubishi i-MiEV).
- 70% warranty threshold: Renault, Peugeot, Tesla, Kia (French sites), most often over 8 years or 160,000 km (7 years or 150,000 km at Kia).
- New range for this model: 395 km WLTP, version Renault Zoe ZE50 R110 (2019-2024) (source). The WLTP standard overstates real-world range, especially on motorways and in cold weather.
What the buyer asks
On a used electric car, the SOH question often comes before the price, in the listing's messages. “What is the battery's SOH?” Then, if they know the subject: “When was it measured? Do you have the certificate?” The range above is what they expect for this model.
What to put in the listing
If the battery has been tested:
- The measured SOH , as a percentage, as the test reports it.
- The test date. An SOH measured a year ago, on a car that has been driven since, no longer answers the question.
- The certificate as a photo , alongside the listing's other photos. The buyer sees it before writing.
Without a test, put the estimate, and say it is one:
“Estimated SOH between 85 and 96% for this model, at this age and mileage (Osmosia simulator, not measured).”
The buyer has the answer before writing, and Osmosia can give it again when they ask.
If the measurement falls below the range, publish it anyway. A documented SOH, even a low one, can be discussed. An unknown SOH stalls the decision.
These questions often come in the evening and at weekends
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