Electric vehicles have come a long way in recent years, but while their range is improving and recharging stations are becoming more common, and there’s more choice on the market, one factor still holding them back, is their price.
Electric vehicles are expensive, with the cheapest models on the market still hovering around the $40,000 mark.
Vehicles like the BYD Atto 3 and the MG ZS EV have certainly put EVs in striking range of the average buyer, they’re still twice the price of the cheapest internal combustion vehicles, like the Kia Picanto, which can be had for under $20,000.
Sodium-ion batteries
The biggest factor driving those higher prices is the cost of those lithium batteries which drive those electric vehicles, but that might be about to change, because an alternative to lithium could be just over the horizon in the form of sodium-ion batteries.
Chinese carmaker BYD is reportedly about to launch a sodium-ion battery as early as this year’s entry level hatchback, the BYD Seagull.
Sodium–ion batteries come with a promise of being safer than lithium batteries and more sustainable.
Without lithium, cobalt, copper, or graphite they’re also cheaper to produce, and sodium is much more readily available than lithium and therefore cheaper to mine. There is a downside however, they don’t offer the same range as a lithium battery.
BYD, however, is confident that the technology has its place in its lower-priced city vehicles where range is not so crucial. It thinks it’s sodium–ion battery can still provide up to 300 km of range, though this is on the somewhat optimistic China Light Duty Vehicle Test Cycle (CLTC).
The reason for that lower range is sodium batteries’ lower energy density compared to lithium batteries, though research is starting to close that gap.
However, sodium batteries have another advantage over lithium, and that’s their resistance to cold weather. They still hold 90% of their capacity at minus 20C, and they also have good fast charging capacity.
Solid state batteries
But sodium batteries aren’t the only technological development holding the promise of cheaper electric vehicles because Australian and Japanese scientists have recently made a breakthrough in solid state batteries that’s improved their durability.
Solid state batteries have long held the promise of greater safety (they don’t spill dangerous liquid when punctured) as well as being faster to charge.
Their problem has always been their durability. Frequent charging damages the electrodes’ crystal chemistry.
But according to website The Driven, research at Japan’s Yokohama National University has tested new materials in electrodes and electrolytes that can produce “remarkable capacity” of 300 mAh/g (milliampere-hours per gram mass) without degrading over 400 charge/discharge cycles.
“The absence of capacity fading over 400 cycles clearly indicates the superior performance of this material compared with those reported for conventional all-solid-state cells with layered materials,” said co-researcher Associate Professor Neeraj Sharma from the University of New South Wales.
“This finding could drastically reduce battery costs. The development of practical high performance solid-state batteries can also lead to the development of advanced electric vehicles.”
The researchers believe that with further work it will be possible to develop batteries for electric vehicles that are cheaper and safer with good capacity and lifespan.
“The development of long-life and high-performance solid-state batteries would solve some of the problems of electric vehicles,” said lead researcher, Professor Noaki Yabuuchi.
“In the future, for instance, it may be possible to fully charge an electric vehicle in as little as five minutes.”