We just got back from the UK, from a whirlwind visit to celebrate a friend’s birthday. The rental car company deemed us as suitable guinea pigs to be upgraded to a fully electric vehicle. Last time we were in the UK, we rented a hybrid, which satisfied the ensuing panic of “what if there are no charging stations where we are going?” The hybrid did have all the bells and whistles, and the adaptive cruise control (I’ll talk more about this) no doubt stopped us from being in a multi-vehicle crash on the motorway.
Now don’t get me wrong, I grew up with fully electric vehicles. Every morning an electric vehicle stopped at our house to deliver the milk, like they did all over the UK. The milk float is proof that electric vehicles can be viable business transportation designed to carry over 1000kg (2205lbs) of cargo. Another observation is that all the land speed records that were set by cars before 1900 were electric. The concept of electric vehicles is solid, and like anything else, the more bells and whistles, the more there is to go wrong.
Being put in an electric vehicle, without expecting it, or having a test drive, is a bit of a surprise. It’s a little like having your first child. Except having 9 months to prepare for a child is better. Although when you bring the newborn home it feels a lot like “um… what do we do now?” Unexpectedly being put in a fully electric car in another country is a bit like that.
So, we drove away from the airport without being told things like “you have to bring it back 80% full” or “guess what happens when the car has a catastrophic sensor failure.” We had enough charge in the battery to get to our first destination. We’d recharge there. Or so we thought.
The UK is full of old buildings. Some, like our old church, were built in the 12th century, and it literally took them 800 years to put in a toilet and bathroom. That’s a long time to wait. Other buildings are more post-WW2/mid-20th century, like the house we were staying at. Like the church, not everything was installed when the house was originally built, and things like electric kettles, and instant hot water heaters, weren’t thought of in the original design. They had been added later. A single person had lived in the house since it was built, and had never needed to use two big electricity guzzling devices at once. Then we arrived with an electric car.
Well, it turns out that we discovered that the main hot water heater for the house, the instant hot for the shower, the kitchen kettle, and the garage where we plugged the car in overnight were all on the same breaker. We didn’t discover that initially as the thermal protection circuit on the house’s extension cord kept blowing. Diving into the car’s settings, we discovered that the car was happily trying to draw 38A from a domestic supply that was only rated for 13A. After changing the car’s settings down to charge at 10A, we discovered all the other things that would blow the house breaker while the car was plugged in.
So we unplugged the car, and went hunting for local charging stations. The car had a friendly app that could find compatible locations. We discovered there were no compatible ultra fast chargers close to us, and the only compatible chargers that were nearby were mid-range to fast-ish. We ended up spending half an hour in the local McDonalds car park charging. The car’s dashboard has a green ring around it when it’s charging, and it tells you the rate of charge including the amperage and voltage.
What we did discover is the exponential increase in time getting to 100% charge. Just don’t bother at a public charger. As the battery gets fuller, the amount of charge required becomes less and less, so the charging rate drops. This drags out the time it takes to charge. That’s fine if you’re not pressed for time, like being plugged in overnight. But if you’re on a tight schedule, that last few percent is a colossal time waster.
Our first major journey was going to be about 250 miles. We’d get there with about 8% battery according to the car’s navigation system, so it recommended a charging station along the way. It was an ultra fast charging location too. Great. Except the rental car now decided to have its catastrophic sensor failure, and light up the dashboard with multiple error messages. There were about 8 or 9 of them sequentially that appeared every time the car was put in drive, reverse or park. Every. Single. Time. They each announced that the Collision Avoidance/Blind Spot Sensor/Rear Auto Brake/Park Assist System/etc. had “Reduced Functionality - Service Required.”
We could’ve called the rental car company for a tow truck, but the car itself didn’t seem all that affected by the loss of sensors. It seemed quite happy to drive around without them. Or maybe I was quite happy to drive around without them. Things like Lane Departure warnings stopped working, but the one thing that did still work was the adaptive cruise control. This is where you set the cruise control for say 70, and if you encounter traffic on the motorway going slower, the car will automatically slow down and follow at the same speed as the car in front. It will also come to a complete stop if the traffic stops in front of you. This is essentially automotive witchcraft and is a must-have.
Our route took us past Heathrow airport, so we stopped at the car rental location and swapped the car out for the exact same model. The exact same model, just with a different, more substantial error, as we were to find out later. We had returned the first car with exactly 80% battery left (a pure coincidence), and that was one of the things the manager replacing the car asked us. And that was how I discovered it needed to be returned like that. Who knew?
Fortunately, our replacement car had about 91% battery when we left the rental location. When we got to the recommended charging place, which was basically a converted field with about 20 charging stations, we found it had a Costa coffee shop next door, so we could walk over there, use the bathrooms, and caffeine up while the car was charging. Now we’d get to our destination with around 45% battery left. Much better.
We made another trip the next day, which was about 50 miles each way. The car told us that the battery level would be pretty low by the time we got back, so we decided to stop at a charging spot once we got near to where we were staying. And that’s when it all started to go wrong.
Most of the charging stations are contactless for credit card payment. You plug into your car. You waive your credit card, and the charging station starts charging the car. Except this one didn’t. Instead of negotiating with the car and starting to charge, everything turned red. Instead of the green ring around the dashboard, it was a red ring, with the comforting word “Error”. We unplugged everything. Plugged it back in, waved the credit card again, only to be met by the same red ring. Maybe it’s a problem with the bay we’re in. So we moved to the next charging bay, only to get exactly the same red ring.
We decided to try a different location. We drove over there, plugged in, waived the credit card, and got the exact same red ring. We unplugged, plugged it back in, waived the credit card, and it was declined. At that point, we gave up, returned to where we were staying, and spent the night wondering how were going to do our 250 mile return trip the next day. The closest location to trade out this car was Manchester airport, and we’d need to recharge first to get there.
Next morning, we packed everything up, and headed for a different recharging station. This time it was an ultra fast charger located at a petrol station. They had more charging bays than petrol pumps, and that was an interesting insight into where this is all going. We plugged in, waived the credit card, and got the red ring of death again.
Fortunately, it was now daylight. I took a much closer look at the charging port on the car. It was a CCS2 connector that could take DC or 1-3 phase AC charging. It looks like this:
The bottom two big pins are for DC fast-charging up to about 350kW (in practice, most of the charging bays we came across were around 125kW, and that had to be shared with other bays). There’s a plastic tip on each DC pin for safety. On our rental car, one of the plastic tips had broken off, and was lodged in the back of its socket, preventing the charging cable from fully engaging and locking. That small piece of plastic was causing the red ring of death. An easy fix if you have a pair of needle-nose pliers.
I didn’t have any. The petrol station didn’t have any. No-one we asked was casually carrying around a pair of needle-nose pliers (like you do). Since this was no time to panic, a hydrocolloid bandage was summoned from the first aid kit, rolled into a long sticky (and insulated) grabby thing, and used to retrieve the plastic tip. We then plugged the charging cable in, it locked, it talked to the car, the sun came out, angels sang, the red ring of death turned a happy green, and the car started charging. Phew.
A bit later, we stopped at the same recharging location that we had visited on our way up. I’d developed a theory and I wanted to test it. Each row had five charging bays, and at the end of the bays was what I assumed to be a commercial generator or transformer that was capable of producing the 350kW DC for fast charging. I’d noticed that the charging rate went down as additional bays were occupied by other cars. So I drove to the back row where I had the entire row to myself. That’s when I noticed that each row of chargers had slightly different charging equipment. This row required a PIN number with the credit card, which was fine by me. I had the whole row, but it didn’t seem to charge any faster, and the exponential slowdown at the last 5% wasn’t worth waiting for.
Conclusions
- Every stop to charge the car took about half an hour.
- Slower chargers that are used to “top up” 10–20% can take just as long as the ultra fast chargers providing 60-70% charge.
- A catastrophic sensor failure doesn’t have to take a car off the road. Luckily, our rental car was able to function like a normal car without its sensors. I think this is important. I imagine a self-driving car would be completely blind without its sensors and unable to function. There’s a happy medium here that car manufacturers need to get right.
- The technology behind batteries is thousands of years old. You can find many ancient civilizations that made crude batteries that were used for electroplating (like the Baghdad Battery) or lighting (the Dendera Light Bulb).
- Recharging isn’t a linear process with chemical batteries. The closer you get to 100% the less charge is needed, and so charging slows down. When you fill a car with petrol/gas, the it will fill the tank in a linear manner and the pump pressure will be constant. A battery doesn’t do that, so we need to find some kind of capacitive storage that will replace batteries and will fill up in a linear manner. That will speed up the recharging process for electric vehicles.