One of the biggest hurdles to widespread adoption of fully electric vehicles is their limited range. Until electric vehicles can compete with the distances possible by internal combustion vehicles that consumers require, they won’t be the standard. However, with the rapid advancement of battery technology, electric vehicles are going father every year. There are also many outside factors that affect driving range and mitigating them can increase it significantly.
The Trouble with Batteries
As everyone knows, electric vehicles run on a sizeable onboard battery. It fills up with current just like a gas tank and can similarly run down to empty. No gas, no go. No juice, no drive.
The problem is, at least for electric vehicles, that gas tanks can hold much more energy in the form of combustible gasoline than most of the rechargeable batteries available today. Gasoline has an exceptionally high energy density, which is a measurement of how much energy is available in a given unit of volume.
Gasoline has an average energy density of about 47.5 MJ/kg. Even the best lithium-ion batteries today can only hope to approach 1 MJ/kg. This sounds like a monumental difference, but it isn’t that titanic of a difference.
Sure, having over 40 times the energy is a huge advantage over batteries, but internal combustion engines only harness, at best, around 25 percent of the energy released when gasoline is ignited. Lithium-ion batteries, on the other hand, harness 90 percent or more of the energy put into them to create mechanical energy.
Why Do Cars Need More Energy?
At the end of the day, however, gasoline engines still create more energy per filled tank than most full batteries. If not as much energy sounds bad, that’s because it is. Vehicles need energy to move. Moreover, vehicles need more power to work against resistance. That means going up hills working against gravity or working against friction by carrying heavy cargo.
So not only do electric car batteries have a reduced driving range, but terrain further cuts down this range as does carrying loads. Heavy lifting and off-road driving must, for the moment, remain the realms of combustible fuel engines. Significant energy density improvements are needed to change that.
Hope for the Future
The good news is, for electric vehicles and their promoters, is that lithium-ion battery technology is by no means mature, meaning there is a lot of room to grow. It does not appear to be scientifically impossible to improve our current batteries’ energy density many times over. It is conceivable to double or triple their energy density, then double or triple it again and continue.
It seems like every year, there is a breakthrough in battery technology that leapfrogs the last and improves their capabilities. Take for example this discovery, that allows for much higher charges in lithium-ion batteries without risking rapid degeneration. The auto companies and engineers alike know that electric cars are a matter of when not if.
Although the electric future is all but certain, how we get there is not. While batteries have driving range problems, we might be able to fix them by getting rid of batteries. In their place, we would use supercapacitors.
A supercapacitor is a material that holds an electric charge to be released later. It differs from a battery, which uses chemical reactions to store and retrieve electrical energy. Think of batteries as a bank that converts and holds your electricity, then converts and gives it back. A supercapacitor is a giant sack to carry your money in.
As for its applications for electric vehicles, a supercapacitor powered vehicle would not only be more energy dense than a battery powered one, but you could also charge it much faster. As fast as filling a gas tank with a pump, and probably quicker.
Lithium-ion batteries can take up to eight hours to fully charge because of the chemical reactions that are taking place, but a supercapacitor just needs a big jolt to fill it up. Conceivably you could be in and out of the charging station in less than 30 seconds, and travel over 400 or 500 miles on a single charge.
The technology is still in its infancy, however. The materials can be created, but whether or not they can be scaled up to vehicles economically and sustainably has yet to be determined. For now, we will have to rely on batteries and their limited driving range.
How Driving Range is Affected
Since we are stuck with batteries, for now, it is important to understand how electric vehicle driving ranges are affected by outside factors. Since they are relatively short compared to internal combustion engine vehicles, every little bit helps take them further. Electric car driving range is a delicate thing that is surprisingly variable. Here are a few things that can have a negative impact.
1. Cold Weather
Electric vehicles perform poorly in cold weather for a couple of reasons. The biggest reason is that the car is using a lot of energy to heat both the cabin for your comfort and the battery to keep it warm. A cold battery does not perform well. All those extra heat requirements take up a lot of battery charge and will shave miles of your range.
Solution: Preheat your vehicle while it is plugged in before unplugging and heading out. You’ll be all topped and heated up, so your vehicle doesn’t need to use its own charge to get things going.
2. Driving Conditions
The driving range of electric cars is significantly reduced any time resistance is applied to them while operating. Resistance means that more energy is required to overcome it, which burns through the charge. Wind resistance or uphill driving increase energy demands, as does rough or uneven terrain. If the vehicle has to work harder, it will run out of juice faster.
Solution: Plan ahead. There isn’t a whole lot you can do to mitigate this beyond choosing a route that is flatter and easier. If at all possible avoid windy areas or days.
3. Driving Style
How you drive can have a negative or positive effect on your driving range. Excessive acceleration and prolonged high speeds increase energy demand and shorten range, for example. Also, heavy braking can waste potential as well, as most electric vehicles nowadays have regenerative braking. This braking system charges your battery as you brake, giving you a little recharge boost every time you do it.
Solution: Observe speed limits, they help keep you efficient. Also, accelerate and brake easily and gradually. Slow acceleration conserves power, and gradual braking allows the regenerative brakes to kick in. Sudden braking does not help you charge, as the excess energy must be absorbed and released quickly in emergency situations by standard brakes for safety.
An electric car moves using electricity. Everything inside the car also uses electricity, and it gets it from the same battery. The radio, phone charger, cigarette lighter, air conditioner, seat heater and any other extra accessory that runs on electricity use up charge that could be used to move the car. They don’t seem like big drains, but all together working for long stretches of time can have an impact.
Solution: Cut back on accessory use. There’s no other way around it. Maybe bring a power bank to charge your devices instead of using your car.
Average Driving Ranges of Electric Cars
At this point, there is quite a range of distances when it comes to electric car driving ranges. It depends a lot on make, model and battery type. Here are a few of the most common.
- Smart Car (84 miles): The Smart Car driving range is pretty short, mostly because the car is so small and must carry a smaller battery. For urban living though, it is more than sufficient.
- Nissan Leaf (107 miles): The world’s best-selling highway-capable electric vehicle has just recently broken 100 miles for its driving range. Not a big step up, but it is much larger than a smart car with five doors.
- Volkswagen eGolf (125 miles): The electric Golf, like most electric cars these days, clocks in a bit over 100 miles in range. 125 is about the new standard.
- Chevrolet Bolt (238 miles): The Bolt trades performance for range. It is the farthest you can go for an “affordable” price.
- Tesla Model S (up to 315 miles): The pinnacle of electric vehicle technology, Tesla brings combustion enginehttps://www.tesla.com/models performance and range in a battery powered car. The only catch is, you have to pay quite a bit to get all that.
A Temporary Stumble
Industry experts predict that when electric cars can go 200 miles on a single charge, consumers will see them as “just like normal cars.” While the Tesla technology is there, the affordable price is not. For now, we will have to deal with limited driving range, but thankfully with some knowledge and foresight, we can stretch that range as far as possible.