How important are BEV battery health certificates?

17 April 2024

The value of a battery-electric vehicle (BEV) can be determined largely by one component. This makes certifying the quality of this part essential to reselling. Autovista24 editor Tom Geggus considers the development and importance of battery health certificates.

Remarketing an internal-combustion engine (ICE) vehicle inevitably involves referencing the model’s age and mileage. For buyers and sellers, these two numbers bring a car’s history, value and potential into focus.

However, these signposts are blurred for BEVs. The standard measures of time and distance are less informative, with next to no indicators about driving or charging behaviour. This makes a battery a black box of information.

‘Essential information regarding the battery status of an electric vehicle is not readily accessible to customers. It is not displayed on the screen, nor can it be automatically retrieved from the battery management system,’ Dr Marcus Berger, CEO of battery diagnostics company Aviloo told Autovista24.

‘Consequently, the electric vehicle battery is unfortunately often considered a black box. Transparency in the remarketing process is crucial for its smooth operation.’

Battery black box

This lack of information creates concern in the used-car market. Both dealers and consumers can struggle to identify BEVs that have been treated optimally. All-electric cars have felt this impact across European used-car markets.

BEV residual values (RVs) have been falling in Austria, Germany, Italy, Switzerland and the UK. These countries saw RVs of three-year-old BEVs drop year on year in absolute and percentage terms during January, February and March. Spain has seen values increase, however, all-electric models remain difficult to sell in the country.

As an indicator of demand, used BEV stock days far exceeded that of all other major powertrains across Austria, Germany, Italy, Spain, Switzerland and the UK. Looking at active adverts from the last 12 months on average, only plug-in hybrids (PHEVs) came close. Meanwhile, diesel, petrol and full hybrids (HEVs) took far less time to sell.

Certificate clarity

In a report published in February, the UK House of Lords acknowledged this lack of certainty around electric vehicles (EVs). It highlighted that consumer confidence in the used-car market is being undermined by uncertainty about battery health.

‘We welcome industry’s work to develop a battery health standard that would give confidence to consumers. The government should accelerate its collaboration with industry to develop a battery health standard that is objective and reliable,’ the report reads.

'EVs unfortunately still lose almost 10% more value after three years than combustion engine cars. Independent battery certificates will bring the values of used EVs to the same level as combustion engine cars,’ Berger said.

Autovista Group underscored how battery health certificates can positively influence used-BEV values in a joint whitepaper. Testing can verify the condition of a used battery in the immediate term, while a move to routine certification promotes better treatment of BEVs more broadly.

Surveying more than 2,000 drivers in the UK, the Green Finance Institute (GFI) found that battery certificates and guarantees held high potential. Respondents ranked these as the two leading solutions that would encourage drivers to buy a used electric car.

The potential of these products was also recognised by dealerships. ‘All of the 21 dealerships that contributed to this report agreed that a battery health certificate or battery value guarantee would provide confidence that the remaining battery health is adequate when selling a used EV,’ the GFI stated.

Transparency for traders

Berger highlighted the indispensable nature of transparency and market regulation when it comes to sustainable long-term development. This is something battery-health certificates could deliver, opening the door to faster and more valuable sales for used-car sellers.

These advantages would be accompanied by enhanced credibility, a positive reputation and strengthened client relationships. This means the benefits of battery certificates would be widespread across the automotive sector.

Berger pointed out that carmakers also need a strong used-EV market to meet sales targets. Meanwhile, customers stand to benefit from the security provided by more detailed and reliable vehicle data accompanied by certificates.

In-person tests

Providing in-person tests, Altelium looks to illuminate an area shrouded in complexities. Alex Johns, the company’s partnership lead, explained to Autovista24 that unpacking battery health is a matter of making analysis meaningful to consumers and dealers.

Depending on vehicle type, Altelium’s battery assessment can be carried out on a stationary BEV via a plug-in diagnostic device or API charge testing. By moving past overly-complicated feedback which can be of little practical use at the point of purchase, these results are simplified and visual. This can go a long way in combatting BEV concerns.

‘There are things which obviously worry people,’ Johns said. ‘Range, we can answer those questions. How long the battery is going to last or what the health of the battery is, we can answer those questions and we can put money behind it to give you proper reassurance.’

Peace of mind

Being able to analyse battery performance allows Altelium to provide peace of mind. Carmakers can provide BEV warranties up to approximately 10 years or 100,000 miles, often covering breakdown and degradation. But Johns explained that under these warranties the degradation trigger point is often set at 70%.

‘Nearly all of them have their trigger points at 70% state of health. That is a long way down,’ he said. ‘You will not get to 70% state of health until things have been going wrong for a long time. So, we have come up with one which we call the sleep easy warranty.’

This 12-month cover provides additional reassurance for used-EV purchasers. If the battery health drops by a set percentage in the first year, Altelium issues a fixed cash settlement. The company also provides extended warranties for up to three years after the OEM’s warranty expires.

So, these tests can illuminate important battery information. Alongside this they can form a foundation of financial support, providing used buyers with even more confidence.

App-enabled analysis

Another method of analysis could require little more than a smartphone. Patrick Cresswell, managing director of ClearWatt told Autovista24 that in shaping a solution, his company was focused on creating an agnostic product. The resulting mobile app was designed to benefit all BEVs from day one.

‘We launched the first iteration of our products about a year ago,’ Cresswell said. ‘Since then, we have tested thousands of journeys. We currently have testers across four continents and there is a lot of international demand for what we are doing. We have also launched some very key pilots with the likes of Octopus Electric Vehicles, Motability and others.’

After installing the ClearWatt app, users enter their car model and license plate. Three drives will then need to be completed with the app running. By recording the state of charge at the beginning and end of these journeys, ClearWatt can assess the battery’s health while controlling for other variables such as environmental conditions.

‘What we have essentially built is a mobile telematics device which in very high-frequency bursts, is giving us all of the information we need about driving style, speed, acceleration profiles,’ Cresswell added. ‘We are also getting elevation of the roads, temperature conditions and wind speed and direction.’

Controlling these factors enables analysis of a BEV’s miles-per-kWh performance, where efficiency reveals the state of battery health. This is then compiled into a graded report, enabling greater confidence during the selling process.

Meeting regulations

Battery tests and certificates will not only bolster confidence in used BEVs but may also prove essential when it comes to new regulations. Recently adopted by the European Council, the Euro 7 emission standards look to set battery durability requirements for BEVs.

Under these proposed rules, the battery in an electric car must maintain a minimum of 80% of its capacity in its first five years, or up to 100,000km. After eight years or 160,000km, these units will be required to retain 72% of their original charge capacity.

Meanwhile, from February 2027, the EU Battery Regulation will require passports for EV and industrial power storage units over 2kWh. This digital record will contain key component information including a unique identifier, as well as the battery’s basic characteristics including type and model.

This passport will also need to provide statistics detailing performance and durability. It will need to be updated throughout the battery’s lifecycle by those repairing or repurposing the unit. This information will need to be shared with the public, regulators and service providers who deal with batteries at the end of their life.

A recent study published by Battery Pass assessed the value of the EU Battery Passport. The benefit to RV assessment was among the consortium’s 12 considered used cases. It confirmed that historic performance and durability information made available through the passport could improve the RV determination process.

This would be the result of reducing the need for technical tests and improving assessment accuracy. This would enable decision-making between second-life and recycling options. So, by making performance assessments mandatory, regulations like these could greatly benefit not only the understanding of battery durability but also BEV RVs.

As regulations require greater durability and companies provide better status insights, the importance of battery certificates can only increase.