The performance of electric vehicles is largely determined by their batteries. But the battery technology used in these vehicles has evolved considerably over the years, and will continue to do so. From lead acid and NiMH to lithium-ion and now several other more exotic battery types, there are a seemingly limitless number of options to choose from. In this article let’s look at some of the historical breakthroughs made in battery technology and how they shaped our technological capability of storing energy for powering EVs.
When the first electric vehicles were introduced in the early 20th century, they were relatively simple machines. But as time went on and technology rapidly advanced, we began to demand more from our vehicles. We wanted higher speeds, longer ranges, and a smoother ride. And miracle of miracles—we got it, and going places with it.
All batteries are made up of the same basic components—cathode, anode, electrolyte and separator—but these components can be arranged in different ways to achieve different functions. Battery manufacturers use different combinations of materials to achieve specific energy densities and costs. The main factors that affect battery performance are energy density, cycle life, power density and temperature operating range. In the future, improvements in battery technology will likely result from research into new materials that have potential for higher energy density and lower cost than current batteries. The most promising candidates with alternative battery chemistries are, lithium–sulphur (Li–S) batteries, sodium-related batteries, zinc-related batteries, aluminium-related batteries, Li–O2 battery, and flow battery. Solid-state Lithium ion Batteries have become a new research hotspot for high safety and high energy-density batteries.
Biting the bullet
In the 21st century, electric vehicle (EV) batteries are starting to look more like the silver bullet we’ve been waiting for: EV batteries are now optimized for energy storage, ride smoothness, and acceleration. The rate at which EV batteries are improving is almost alarming. For example: Tesla’s Model S recently updated its car line with a new battery that can accelerate from 0 – 60 in just 2.5 seconds with a range of up to 315 miles for only $10,000 more than the previous model. Likewise, Nissan has released a new version of its Leaf electric car with a drive range of 107 miles and an acceleration of 7.5 seconds from 0 to 60 mph. And those numbers will only get better as EV batteries improve.
Batteries are the lifeblood of electric vehicles. The more we understand about how they work and how to optimize them, the better we can design the cars around them. As with newer chemistries, we’re also seeing new developments in Digital Twin based battery analytics that will provide industry-leading predictive analysis of data including when batteries start to fail. Digital Twins are a digital representation of physical assets or processes, such as a car, a building, a machine or a piece of equipment. Models created from data inputs can be used to predict future performance and potential failures.