Major automakers are vying for dominance in the electric vehicle sector, striving to meet market and consumer demands. Volvo has pledged that all its new models will be equipped with an electric motor starting in 2019.
Modern electric motors employ modern design concepts, resulting in compact structures, extremely high energy efficiency, and zero emissions. However, to power vehicles, automakers must pair the motors with batteries, which is precisely the crux of the current limitations on the promotion and application of electric vehicles.
The constraints of lithium batteries on the promotion of electric vehicles
Today, most electric vehicles use lithium-ion battery packs, and lithium batteries are also widely used in devices such as smartphones, tablets, and laptops. According to research by McKinsey & Company, a globally renowned consulting firm, the price of lithium-ion battery packs for electric vehicles has fallen by nearly 80% since 2010, but they remain expensive.
The battery pack in the Chevrolet Bolt, owned by General Motors, costs over $15,700 (approximately £12,150), accounting for more than 40% of the vehicle's price. According to McKinsey, it may take another 10 years or even longer for the price of electric vehicles to fall to the level of gasoline vehicles.
Although electric motors are more energy efficient than internal combustion engines, batteries store only a small fraction of the energy required for fossil fuels like gasoline and diesel. Some electric vehicles today even have a range of only around 100 miles.
Finally, even if the price of lithium batteries eventually falls, safety issues remain. These batteries require cooling to prevent overheating, and their liquid electrolyte is flammable. If the battery is damaged, it can easily ignite.
Automakers' Response
"When it comes to electric vehicles, cost, energy density, and safety are all crucial factors," said Jun Liu, a materials scientist at the U.S. Department of Energy and a director of the Battery500 consortium. The consortium has invested $50 million to improve the performance of lithium-ion batteries and has received support from TSLA and IBM.
The "500" in "Battery500" signifies doubling the energy density of lithium-ion batteries, as their energy density is typically around 250 Wh/kg. Liu stated that this means optimizing current lithium-ion battery technology and building large-scale production facilities in a short period, such as TSLA's Gigafactory in Nevada.
Liu stated, "If we can increase the scale of manufacturing, we may significantly reduce the production cost of lithium batteries." TSLA aims to independently establish three super-factories globally, each with a super-strong production capacity equivalent to the total global lithium battery production in 2013.
Furthermore, the currently used graphite anode needs to be replaced with a silicon electrode. Silicon has a higher energy storage capacity than graphite, but during charging and discharging, the material is prone to expansion and contraction, and reacts with the electrolyte until the electrolyte is depleted. Due to these problems, lithium batteries with silicon anodes, which are still in the experimental stage, will be phased out more quickly than graphite batteries.
Solving these problems might take five years, but it should increase the energy density of lithium batteries to 350 Wh/kg. However, he admits that doubling the energy density of lithium batteries would take at least another ten years.
User demand and concerns about electric vehicles
However, Jessika Trancik, a professor at MIT who studies energy, says that despite these challenges, the demand for electric vehicles remains unabated.
According to her research, more affordable electric vehicles such as the Nissan Leaf or Ford Focus can not only meet people's daily driving needs, but also reduce greenhouse gas emissions by 30% or more.
She stated, "The real challenge lies in helping people overcome their concerns about the range of electric vehicles. When users buy a new car, they want to know its range. They want to know if their vehicle can reach its destination for a long journey. Rather than waiting for the successful development of new batteries, increasing electric vehicle charging infrastructure or adopting new business models such as car sharing might be a faster way to promote electric vehicles."
