Optimising battery use is central to the success of electric vehicles

We need to change the way we think about electric cars, particularly when it comes to range and charging.

We need to change the way we think about electric cars, particularly when it comes to range and charging.

We know that electric vehicles are a growing market, with companies around the globe investing in new projects and technologies. Right at the heart of the success, or otherwise, of electric vehicles is the battery, or power pack. TSC CEO Paul Campion takes a look at the impact batteries could have on consumer behaviour, manufacturing, depreciation and even the national grid.

The energy density of electric storage is lower than the energy density of hydrocarbon fuel. Of course, if hydrocarbon fuels were a new technology today, they would never come to market. Imagine announcing that you wanted to power our transport systems on a toxic, explosive, highly flammable material. Good luck with those health and safety checks! Yet, that’s what we drive around in, every day of the year.

These volatile hydrocarbon fuels have dominated transport for the last hundred years partly because they’re extremely energy dense. It is well known that some of the very first cars, at the end of the nineteenth century, were electrically powered. The dominance of the internal combustion engine came about despite their noisy, smelly and temperamental natures because the power and range offered by a tank of petrol offered convenience far beyond the rudimentary batteries of the time. The energy density of batteries is a crucial element in our transition to electric vehicles.

We need to change the way we think about electric cars, particularly when it comes to range and charging. One of the reasons that electric cars are on the point of becoming mainstream is that consumers can now expect to get a range of 150-200 miles out of each charge.

Range is often the consumer’s top concern when it comes to deciding whether to choose an electric vehicle. Despite the fact that most journeys are very short, when considering whether to buy an electric car people tend to bring to mind that rare occasion when they drive to the other end of the country – perhaps to see family at Christmas, or go to Cornwall for their holiday.

Because they don’t think the car will have the range for that once-a-year journey, they decide it’s not for them, despite the fact that it would work for them the other 364 days each year. It would probably make financial sense to choose the electric car and rent a vehicle for that one long journey each year, but that doesn’t seem to be how people think.

As well as the problem of range, consumers will often worry about how long it takes an electric car to charge. Once again, I think we need to change our way of thinking on this. Yes, it takes longer to charge an electric car from zero to maximum than it does to fill a petrol tank. But we shouldn’t be thinking of these as the same thing.

We don’t charge our laptops from flat to maximum in the middle of the workday. We charge up overnight, so that we don’t run out of power halfway through the afternoon. That’s how people would use electric cars; charging them up overnight when they’re not in use – so actually it’s likely that people would waste less time than if they are stopping at petrol stations every couple of days.

What happens to batteries when they can’t run a car any more? Existing technology means batteries don’t have an infinite life. The thousandth recharge cycle is not as efficient as the first recharge cycle. So the range of the vehicle reduces over time.

It’s possible that leasing companies will depreciate batteries separately from cars. This is because it’s likely that electric cars will last a lot longer than petrol or diesel cars as most degradation is caused by vibration – and electric cars vibrate much less than traditional cars. But power packs have a much shorter lifespan. So we may end up with a system where there are two depreciation schedules for one vehicle – one for the car itself and one for the power pack.

If a car owner finds that their power pack has degraded to the extent that it’s no longer meeting their travel needs, they can buy a new one and put the old one to good use on the domestic front. An old power pack could charge up in the garage overnight when electricity is very cheap. Then it could be used to run the household during the day, when electricity is expensive.

This kind of thinking could also operate on a macro level. Let’s do the sums. 10% of the passenger car fleet in the UK is about 2.5 million vehicles. If they each have a 20kWh of battery capability (which is very conservative) – that’s 50GWh of storage capacity. The average nuclear power station generates about 1 GW. So the country’s electric cars have a power storage capacity that presents a meaningful number when compared to the capacity of the national grid.

This creates an opportunity for the country. We could, for example, store up excess energy generated from wind power, and use it to supplement the grid during high-demand periods.

So what’s stopping us from doing this right now? Data. We would need to know what’s plugged in, what its storage capability is, how long it’s expected to be plugged in and we would probably need a real-time auction enabling the buying and selling of power, because organisations are unlikely to do all this for free.

Where we make cars is dependent on where we make batteries. A modern car battery is composed of thousands of small chemical plants (a cell is, after all, a package of highly reactive chemicals; that’s what makes it work) managed by some very sophisticated electronics. Moving them around is risky (lithium batteries are banned on flights), particularly when the management system is not powered up.

To minimise risk, it’s important for battery manufacturers to be close to car manufacturers. Of course, it’s not just about safety. Keeping these two parts of the production chain close to one another also minimises the expensive and time-consuming shipping of large, heavy batteries – important for both financial and environmental reasons. Basically, if we aim to manufacture electric cars in the UK, we need to manufacture batteries here too.

The UK Government is directly intervening to motivate manufacturers to establish battery (and, therefore, car assembly) in the UK with the Faraday Challenge. A pilot plant will be built to enable manufacturers, irrespective of their proprietary chemistry or packaging technology, to manufacture at pre-production scale to prove their products and processes. The UK is one of the leaders in the adoption of low emission vehicles; we hope that it can become a leader in their manufacture as well.

Join us for the launch of Electric Vehicles: Towards an Excellent User Experience, a new report published by the Energy Systems, High Value Manufacturing, Future Cities and Transport System Catapults on behalf of Innovate UK on the 7th June in Coventry. Find out more here.

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