Not sure if I'm allowed to post a letter published in the May edition of Car Mechanics magazine. I'm sure a mod will delete it if not.

It's from the owner of one of the last Mk1 Leafs. Battery life isn't the biggest worry in running an older EV. Some of the prices are eye watering and would likely write the car off

? CM published two interesting letters in your August 2022 issue regarding living with an EV and the hidden costs of owning an EV. I agree with Nigel Gutteridge that some of the hidden costs to owning an EV are never apparently discussed, but the battery is only one of many hidden costs.

I bought my Nissan LEAF new 9.5 years ago. It has covered 85,000 miles and still has the original main (HV) battery. Battery life was one of the concerns I had in mind when I bought the LEAF. I wanted to factor in battery replacement as a future cost to balance against the savings possible with the reduced running costs, and right from the start it was impossible to find any figure for the battery replacement cost. The dealer network was very evasive. It is still difficult to get a figure from any Nissan dealer. I’m not sure that many Nissan dealers are interested in maintaining an out of warranty EV, and I suspect that the Nissan business model involves steering customers away from keeping an older EV on the road, and towards buying a nice shiny new EV. This is my personal experience.

The apparent lack of manufacturer concern for older EVs kind of defeats the environmental responsibility ethos somewhat.

Back to my car. Being a Japan built model, made in 2013, it is one of the last of the series one cars. The UK built series two cars had substantial changes under the skin when they were introduced in late 2013, and the battery and electronics technology has been developed continually since.

But I am happy to report to Nigel Gutteridge that seven years is a somewhat pessimistic battery life estimate. At nine years I still have around 85% of the original battery capacity remaining, and that still amounts to a useful 70+ miles range from what is now regarded as a very small 24kWh battery. I can achieve 4+ miles per kWh with this car, and, infact, it is this figure that the prospective EV buyer needs to know.

Look at any EV review and you see the projected vehicle range from a full charge, but this is a rather vague and meaningless piece of information, because we all know that manufacturers data is optimistic, and the actual vehicle range is entirely dependent on the skill of the driver. Rarely do you see any data relating to the energy efficiency of the vehicle. Let me explain what that means. The data we really need in an EV review is along the lines of ‘The vehicle range should be 250 miles based on an average energy efficiency of 3.5 miles per kWh’. The vehicle dashboard in an EV will show the energy efficiency in the same way a petrol or diesel car will report the current and average MPG figures.

Nearly forgot why I started typing. Hidden costs... At eight years 11 months, I experienced my first panic attack as an EV owner when I got into my car one morning (I charge at a maximum rate of 10amps overnight) to find that it would not power up and that the dash was alight with an interesting new range of warning lights and alarm sounds. First thought was ‘expensive’! It took 10 weeks of dealing with one inadequate Nissan Dealer (wrong diagnosis) and the poor excuse that passes for Nissan Customer support, which led me to scouring the internet and the aftermarket EV network for diagnostic information and advice. Many thanks to Cleveley EV for helping me to find the cause of the failure, and to Marshall Nissan in Leicester for confirming my diagnosis and making the repair. This led to me performing my own diagnostics, the results contradicting the official Nissan fault diagnosis.

I can report to Nigel that the hidden costs are as follows... If the VCM fails, the replacement unit (all of the HV systems report to the car through this module) will cost £2200 to replace and code up. The part cost is around £600. The rest of the cost is installing it (the VCM sits behind the glovebox) and programming. That’s right, the charge for installing and coding the VCM is £1600!

At the moment I believe I am correct in observing that the independent EV network cannot yet code up a virgin VCM if the old unit cannot export it’s vehicle programming data, and according to Nissan, once coded up, a VCM cannot be re-coded to work with a different car.

A replacement vehicle charging unit (this is the unit that is built into the EV and manages the incoming power connection to charge the HV battery and also manages the maintenance of the 12V battery charge) has a replacement cost of £2800. This unit failed on my car and needed to be replaced. Second-hand units were scarce and offered at stupid money so I decided to buy new and get manufacturer warranty on the part.

Caution! Be aware that if an inexperienced repair agent (and, sadly, that includes some Nissan Dealers) diagnoses a VCM failure, they will also state that there may be other module failures present on the HV side of the car that cannot be diagnosed until the VCM is replaced. In my case the vehicle charging unit had failed in such a way that it also shut down the CAN lines on the HV side, giving the symptoms of a failed VCM. If I had followed the advice of the first Nissan Dealer I turned to for help, I would have ended up spending a total of £5000. That’s a big enough bill to make the car an economic write-off.

There are other major units on an EV that could cost big money to replace, such as the motor drive inverter, the brake master cylinder (a really sophisticated piece of kit on the LEAF, and an expensive item to replace) and any one of the half dozen or so on-board computer modules.

So, returning to Nigel’s initial concern, battery condition and life expectancy is largely dependent on the way the vehicle has been charged during its life, and I would offer two pieces of advice to anyone wanting to buy an older EV.

1) Ask how often the vehicle has been used for long journeys and how often it is ‘fast charged’ at motorway services. Fast charging is known to accelerate battery degradation due to battery heating. I have never fast charged mine and this probably explains the good health of the vehicle battery.

2) Look at the EV battery health indicator. Most EVs have some means of displaying the battery health.

When it comes to the hidden cost of EV ownership, my own concerns are for what happens when the vehicle model reaches 10-years-old and the manufacturer is no longer obliged to provide parts support. If there are no other sources for new replacement EV specific parts, the vehicles will be worth only scrap.

Remember that there are many suppliers for the regular car stuff, such as track rod ends, road springs and brake pads and discs, but for charger units, VCMs and inverter units? Hope this situation improves!

Tim Baker