The Final Barrier for the EV is Consumer Perception, Not Technology Maturity
The full version of this article was originally published in Electronic Design October 7, 2013.
By Micheal Austin
The electrical vehicle has been around for more than a century and its most critical subsystem has always been the propulsion system, which includes three main components: a power converter, the propulsion motor and an energy storage system. The latter supplies energy to the electric motor, converting to mechanical energy and traction to the wheels. To most, it has a much simpler name: the Battery.
Like the electrical vehicle, rechargeable batteries have a long history that comes with connotations that cloud people’s perceptions of electrical vehicles, potentially slowing the adoption of EV’s. The general public has anxiety over battery technology that has no doubt created trepidation amongst automakers as to whether it makes sense to push ahead with the development of electric vehicles.
The problem is memory – literally. What was true a decade ago is not true today – there are no batteries today that have a “memory effect”, but if you’re a child of the ’80s you remember batteries not having the same capacity or longevity if you didn’t fully discharge them or fully charge them. Public understanding of battery technology and capability today is the biggest barrier to wider adoption of electric vehicles. We have cleared the technology hurdles, but not the perception issues.
Finding the right mix
Over the past few decades, the chemical content of batteries has changed. Until the mid-1990s, most electric vehicles used Lead Acid batteries, although some used Nickel Cadmium. Today, most commercial hybrid-electric vehicles use NiMH batteries, but are transitioning rapidly to Lithium-ion and Iron-phosphate derivatives. With the Tesla Roadster or high-end Model S, users can travel more than 200 miles per charge on a Lithium-Cobalt or tri-metal chemistry. GM’s Chevy Volt plug-in HEV and the Nissan Leaf (BEV) also use a version of Lithium-ion batteries with a Lithium-Manganese spinel chemistry. Lithium-based technologies, Lithium-ion and Iron-phosphate batteries are proving to be good options for PHEVs and BEVs.
One of the reasons Lithium-ion batteries are appealing is because they can output high energy and power per unit of battery mass; this means they are 4-8 times lighter and smaller than Lead-acid batteries.
Unfortunately, lithium-ion batteries are the most expensive option for PHEVs and BEVs right now and contain toxic electrolytes that make disposal a serious concern. Another option is lithium iron phosphate, lithium ferrophosphate (LPF) or iron-phosphate (FE) batteries. These batteries have about a 15 percent lower energy density, but have longer cycle-life, great power density and are more thermally and environmentally stable than common lithium-ion batteries, which makes them safer in all respects. They are also 30-40% less expensive.
Small things add up
The development of cell phone technology and the evolution of mobile devices have certainly aided advancements in battery technology for electric vehicles. We have been able to leverage manufacturing scale and components and even driven down the costs, for example.
However, the cost of a battery in a car is amplified because we’re not just talking about a single cell, which you have in your mobile phone; we’re talking about thousands of cells strung together and the costs such as labor and materials to connect those cells together. Tesla’s roadster, for example, was reported to have more than 8,000 cells. Each cell was independently monitored for things such as voltage and temperature. That means overhead for electronics.
The reason why monitoring is so important is each of those cells is a very high energy and potentially volatile device in adverse conditions. You can only pack so much energy into a device like that and risks are inevitable. When these batteries go into catastrophic failure they “rapidly dissemble” – they don’t just spit out their contents, they can do very bad things. That’s why you see really big headlines for EV fires and battery recalls for devices such as laptops.
When you use a high energy density technology in vehicles and you’ve got 8,000 of these strung together, you have to include a lot of safety elements that increase the cost of that system. Let’s be clear: EVs are safe. They are as safe to drive as any gasoline-powered vehicles and Iron-Phosphate batteries are fire-safe, for example, even if they are slightly less energy dense. Iron-Phosphate batteries can be cycled more than 7000 cycles; that means they can be fully discharged every day for more than 20 years of life! We have batteries today that will outlive the vehicles that they are in. There is no longer a barrier of longevity or calendar life for these batteries.
One of the main challenges for mass adoption of electric vehicles by consumers is range. This of course could be addressed by increased battery storage and infrastructure. Charging stations could easily become as common as gas stations and rest stops along every highway in America. Every motel, restaurant, shopping center and grocery store would have a charging station, making long road trips in an electric vehicle a viable reality.
The beauty of the all-electric vehicle, besides being environmentally friendly, is its simplicity. An all-electric vehicle has 30 percent fewer parts than a standard internal combustion engine; it’s also more reliable. It also requires less maintenance in part because there are fewer fluids to change out and regenerative braking spares brake pads.
Long live the battery!
Regardless of what type of rechargeable battery ultimately becomes the standard for electric vehicles, one hurdle that has definitely been overcome is longevity. We have battery technology that will last 30 years, outliving any car. There are vehicles on the market today that can go 230-300 miles on a single overnight charge – approximately five hours in an owner’s garage – and be able to drive that distance the next day without a mid-day charge to extend range.
But perceptions of drivers must be managed and shifted. In the same way mobile phone technology has contributed to the development of rechargeable batteries in electric vehicles, this example can be used to change attitudes of the general public.
Take wired landline phones for example: You could pick them up any time of day, any time of week and talk as long as you wanted, you didn’t think about power. And you didn’t worry about being tethered.
When the first mobile phones were introduced, they barely offered 20 minutes of talk time, but eventually the paradigm shifted and so did people’s expectations. We don’t expect a cell phone to last all week on a single charge, but we still expect a vehicle to last all week after we have filled the tank with gas? The difference is that we are okay with plugging in our phone to charge it whenever the opportunity comes up – not just overnight, but while we are at work, at lunch, traveling, at the airport or at home making dinner, for instance. We’ve come to an unspoken agreement that we charge whenever we have down time. We don’t expect it to last two days in talk time. We don’t expect it to last a week long in standby time and that’s because we have changed our thinking.
This shift is happening with EVs in some parts of the world. There are now over 1,000 electric taxis running in Shenzhen, China, and all of them are in cars that only go 187+ miles average (300 Km) on a single electric charge with air conditioning running. However, they are driving totals of 300-400 miles per day (480 – 800 Km) because they are “opportunity charging”. When the cars start out in the morning they are fully charged, but as with taxis in most jurisdictions around the world such as London or New York, they are idle about 40 percent of the time. When taxi drivers stop to go to the bathroom, they plug in. When they go for lunch breaks, they plug in. When they are sitting in the taxi queue, they are plugged in.
A change in thinking occurred there to revolutionize this high-utility, long-range application. This can happen in the Americas, if not immediately for consumers, certainly for high-utility public transportation. There are no two-shift taxi operations or bus routes in the United States that couldn’t be covered with an electric taxi or bus with opportunity charging.
A change in thinking needs to happen for electric vehicles to see wider adoption. The battery technology is there; we just have to shift attitudes and our thinking, so that drivers are as comfortable “opportunity charging” their vehicles as they are with their “untethered” cell phones, while at the same time providing the infrastructure to do so.
We saw a revolution from land-lines to mobile-telephony occur within a decade. This same new “battery-based” energy revolution will occur in the transition away from gasoline to electrified transportation.
MICHEAL AUSTIN — Vice President – BYD America
Micheal Austin received his degree in Design Engineering as well as a Masters Degree in Mechanical Engineering from BYU. He worked for Motorola 15 years in functions including ODM Director for the Mobile Devices Business responsible for over $3B in purchases annually and serving as Motorola’s Global Energy Commodity Manager, purchasing Motorola’s battery products. He was selected as Motorola’s Distinguished Innovator (with 22 US patents) in 1999. He has considerable Asian International business experience which proves invaluable in his current role as Vice President for BYD America. BYD is a $40B Chinese company listed on the HKE and has over 200,000 employees.