# Why Are Used EVs Hard to Sell? Battery Health Degradation Explained

**Used electric cars sit on the lot because buyers cannot judge the state of the battery. Across all cars the technology holds up well: after 200,000 to 300,000 kilometres capacity stands at about 87 percent according to a P3 study, and in the Aviloo report of 2 September 2026, 16 of 20 models reach a median state of health above 90 percent at 150,000 kilometres. The spread is what matters: two cars of the same model differ by as much as 12 percentage points. Only a measurement on the single car answers the buyer's question. A flash test takes 22 minutes through the OBD port and costs from CHF 99 in Switzerland.**

An electric car stands on your forecourt. The enquiries come in, the test drives run, and then the same sentence falls as last time: "And the battery?"

That one question decides the sale. The good news: it can be answered today, with a number, in 22 minutes.

## Why the market hesitates

The AGVS, the Swiss garage association, describes the situation plainly: used electric cars are currently more burden than business for dealers, and doubt about the battery is the reason. Markus Aegerter of the AGVS also names the source of the misunderstanding: many people compare a car battery with the one in a mobile phone, although the technology behind it is an entirely different thing, including active temperature management.

That hesitation reaches the prices. Between January and April 2025, used electric car prices stood 12 percent below the year before. Individual premium models go further: the AGVS names the Porsche Taycan, which after three years fetches about half its new price. _([AGVS: why the market for used electric cars is stalling](https://www.agvs-upsa.ch/de/news-medien/news-stories/warum-der-markt-fuer-elektro-occasionen-stockt/))_

The annual statistics put the same drivetrain at the top of the decline.

**Used car price decline 2025, in percent**

| | |
| --- | --- |
| Battery electric | 8.3 |
| Diesel | 6.0 |
| Mild hybrid | 5.0 |
| Full hybrid | 1.2 |
| Petrol | 0.2 |

_([AutoScout24 annual data 2025](https://b2b.autoscout24.ch/autoscout24-jahresdaten-2025-wachsende-auswahl-sinkende-preise-und-zunehmender-wettbewerb/))_

## What the battery actually delivers

Hold the doubt against the evidence. A study by the analysis house P3 concludes that car batteries still hold about 87 percent of their original capacity after 200,000 to 300,000 kilometres.

The largest evaluation so far comes from Aviloo and appeared on 2 September 2026. It rests on more than 500,000 battery tests.

| What was evaluated | Result |
| --- | --- |
| Battery tests evaluated | more than 500,000 |
| Models examined | 20 |
| Models with a median state of health above 90 percent at 150,000 km | 16 of 20 |
| Best value, Hyundai Ioniq 5 | 92.8 percent median |
| Difference between two cars of the same model | up to 12 percentage points |

_([electrive on the Aviloo Certified EV Battery Report, 2 September 2026](https://www.electrive.net/2026/09/02/batteriegesundheit-von-e-gebrauchtwagen-schwankt-stark/))_

Aviloo's chief executive Marcus Berger sums up the core in one sentence: battery health differs strongly between models, and more strongly still between individual cars of the same model.

## Why the buyer is right anyway

That last row of the table explains the whole market. The average is good. The single car can sit above or below that average, by as much as 12 percentage points.

A buyer who asks about the battery is therefore behaving sensibly. They are not buying a model, they are buying a car. A general statement about how long batteries last does not answer their question.

The practical conclusion follows, and it is good news: the question can be answered on the car. Measure the value and you stop selling against a doubt and start selling with a number.

## The test that already exists

Two procedures are available in Switzerland. The flash test runs through the OBD port and takes 22 minutes. The TCS has offered it since 2024, and EnergieSchweiz lists it in its electric-mobility roadmap as a measure for the used market. _([EnergieSchweiz, electric-mobility roadmap](https://www.energieschweiz.ch/programme/roadmap-elektromobilitaet/massnahmen/aviloo-flash-test-standardisierter-batterietest-fuer-elektro-occasionen/))_

|  | Flash test | Premium test |
| --- | --- | --- |
| Duration | 22 minutes | several days, one discharge from 100 to 10 percent |
| Connection | OBD port | measuring box stays in the car while it is driven |
| Result | state of health and certificate | plus the condition of individual cells |
| Price in Switzerland | from CHF 99 | from CHF 299 |
| Fits | every trade-in check | high-value cars and disputed cases |

_(Prices and durations follow the published offers of [autocentrum.ch](https://www.autocentrum.ch/aviloo-batterietest-e-auto) and [eGarage](https://egarage.ch/de/dienstleistungen/aviloo-batterietest/), read on 12 September 2026. Offers differ from garage to garage.)_

Weigh the flash test against your standing days. A car that stands four weeks longer because of one open question costs you a multiple of the test fee.

## What the number does in the listing

The value is becoming a search criterion. AutoScout24 is introducing a standard battery certificate for listings in the first half of 2026 and testing a state-of-health filter in the search criteria. _([EnergieSchweiz: battery certificate for used electric cars](https://www.energieschweiz.ch/programme/roadmap-elektromobilitaet/massnahmen/batteriezertifikat-fuer-e-occasionen/))_

That changes the position of every listing. As soon as buyers filter for a minimum value, only cars with a stored number appear in that search. A tested car gains a visibility an untested one cannot reach.

Since 2026 the certificate can also be paired with a guarantee. Aviloo covers used electric cars for one year or 20,000 kilometres: if battery condition falls below an individually calculated threshold in that time, the buyer receives EUR 3,000 plus the cost of the test. _([AUTO&Wirtschaft on the extended Aviloo certificate](https://auto-wirtschaft.ch/news/aviloo-zertifikat-weiterentwickelt-mehr-vertrauen-auf-einen-blick-beim-e-auto-verkauf))_

## From February 2027 the number is there anyway

The EU is making the value binding. From 18 February 2027 every new traction battery above 2 kWh needs a digital battery passport. It documents state of health, origin, carbon footprint and materials, reachable through a QR code, with different access rights for buyers, dealers, workshops and recycling.

Markus Peter, technical director of the AGVS, names the purpose: the battery should be used as long and as effectively as possible, as a vehicle component, as an energy store and in recycling. The details do not yet apply to Swiss garages one by one, yet the trade is closely woven into the EU market, and the passport becomes a market-access criterion in Europe. _([AGVS: the EU battery passport is coming](https://www.agvs-upsa.ch/de/news-medien/news-detail/news/der-eu-batteriepass-kommt/), 25 September 2025)_

The direction is therefore clear. Within a few years the number belongs to every car. Whoever works with it today has already built the routine, and the customer's trust, before everyone else does.

## Your routine at trade-in

1. **Measure at trade-in, not at sale.** The value belongs to the appraisal of the car, exactly like mileage and service history.
2. **Put the value into the price.** A high state of health carries a premium, a low one a discount. Both can be evidenced and both can be explained.
3. **Write the number into the listing.** Value, test date and provider, in that order. Three details are enough.
4. **Hand the certificate over with the car.** The buyer then holds a document that answers their biggest question.
5. **Offer the guarantee where it fits.** It turns the remaining uncertainty into a fixed amount.

## In short

- The market hesitates on used electric cars, and the reason is the battery.
- Across all cars the technology holds up: about 87 percent capacity after 200,000 to 300,000 kilometres, and 16 of 20 models above 90 percent at 150,000 kilometres.
- Two cars of the same model differ by as much as 12 percentage points. That is why the measurement on the single car counts.
- 22 minutes and from CHF 99 give you a number you can write into the listing.
- From 18 February 2027 the EU battery passport carries that figure anyway. The routine pays off now.

How do you handle it today? Vote below, and you will see straight away how other readers answer.

## More on this topic

- [Measure visibility, do not guess it](https://autopowersuche.com/en-ch/dealer/page/measure-visibility-do-not-guess-it) — how a car reaches page 1 and stays there.
- [What is AEO?](https://autopowersuche.com/en-ch/dealer/page/what-is-aeo) — why a well-kept data field counts for AI assistants too.
- [The Swiss car trade in numbers](https://autopowersuche.com/en-ch/dealer/page/swiss-car-trade-in-numbers) — the market data behind this article.

## Sources

- [AGVS: why the market for used electric cars is stalling](https://www.agvs-upsa.ch/de/news-medien/news-stories/warum-der-markt-fuer-elektro-occasionen-stockt/) — with the P3 study and the 12 percent price decline.
- [electrive: battery health of used electric cars varies widely](https://www.electrive.net/2026/09/02/batteriegesundheit-von-e-gebrauchtwagen-schwankt-stark/) — Aviloo Certified EV Battery Report, 2 September 2026.
- [EnergieSchweiz: Aviloo flash test, a standardised battery test for used electric cars](https://www.energieschweiz.ch/programme/roadmap-elektromobilitaet/massnahmen/aviloo-flash-test-standardisierter-batterietest-fuer-elektro-occasionen/), offered by the TCS.
- [EnergieSchweiz: battery certificate for used electric cars](https://www.energieschweiz.ch/programme/roadmap-elektromobilitaet/massnahmen/batteriezertifikat-fuer-e-occasionen/) — certificate and state-of-health filter at AutoScout24.
- [AUTO&Wirtschaft: the Aviloo certificate extended](https://auto-wirtschaft.ch/news/aviloo-zertifikat-weiterentwickelt-mehr-vertrauen-auf-einen-blick-beim-e-auto-verkauf) — a guarantee over one year or 20,000 kilometres.
- [AGVS: the EU battery passport is coming](https://www.agvs-upsa.ch/de/news-medien/news-detail/news/der-eu-batteriepass-kommt/), 25 September 2025.
- [AutoScout24 annual data 2025](https://b2b.autoscout24.ch/autoscout24-jahresdaten-2025-wachsende-auswahl-sinkende-preise-und-zunehmender-wettbewerb/) — price development by drivetrain.
- [autocentrum.ch](https://www.autocentrum.ch/aviloo-batterietest-e-auto) and [eGarage](https://egarage.ch/de/dienstleistungen/aviloo-batterietest/) — published prices and procedure, read on 12 September 2026.

## FAQ

### How recent does a battery certificate have to be at the point of sale?

Measure at trade-in, and measure again when a car has stood for more than half a year. The buyer should see a date that matches the moment they buy.

### What do I do with a car whose value comes out low?

Name the value and adjust the price. A low value with evidence sells, because the buyer knows what they are paying for. Openly stated weaknesses cost far less than a complaint after the sale.

### Is the test worth it on a car under CHF 15,000?

Yes, as soon as the car stands longer than two weeks. The flash test starts at CHF 99, and every extra standing day costs tied-up capital, space and insurance. The sum works out after only a few saved days.

### What applies if the measured value falls under the manufacturer guarantee?

Then the manufacturer guarantee applies and the case belongs to the brand. The Aviloo report records that most models pass the usual 70 percent at 160,000 kilometres. Outliers exist, which is exactly why you measure.

### Flash test or premium test, which do I take when?

The flash test belongs in the trade-in check, because it is finished in 22 minutes. Choose the premium test for high-value cars and whenever the condition of individual cells is under discussion.

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Source: https://autopowersuche.com/en-ch/dealer/page/why-used-evs-are-hard-to-sell — Auto Power Search