Speaking at the Cleantech Forum in San Francisco last month, Musk announced that it wouldn’t be battery technology that pushed the electric car forward, but capacitor technology:
“If I were to make a prediction, I’d think there’s a good chance that it is not batteries, but capacitors.”
Capacitors are already in everyday electronics, used as devices for storing electric charge. At its most basic, a capacitor consists of two conductors separated by a non-conductive region, that is able to deliver quick bursts of power. They can also be charged and discharged many times more than a battery without wearing out the materials inside.
Obviously this would be hugely beneficial to the electric vehicle industry. A supercapacitor that can deliver enough power to a vehicle to allow it to travel large distances that doesn’t need to worry about degrading battery performance would be the Holy Grail of EV power.
The CSIRO is actively working on supercapacitor technology, and claim there are plenty of benefits for using them in electric and hybrid vehicles:
Supercapacitors offer many benefits:
• They can be recharged very quickly (in a matter of seconds)
• When fitted alongside a battery can extend battery life by up to five times by ‘levelling out’ high power demands on the battery (load levelling)
• They can be manufactured in any size and shape
• They can be retrofitted onto existing designs
• The devices are generally made from low-toxicity materials.
We’re still a little while away from seeing batteries fall by the wayside in a supercapacitor revolution. A more likely scenario is that we’ll see these capacitors used in conjunction with smaller batteries to improve battery performance in electric and hybrid vehicles.
According to Professor Gerhard Welsch from Case Western Reserve University, capacitors have the ability to deliver and absorb energy faster than a battery. Speaking to Gizmag last year, Welsch claimed:
“Electric vehicles need power inverters to convert battery power into higher voltage AC power for their electric motors and to harvest braking power.”
Having capacitors eliminates the need for inversion as they can deliver the energy at high voltages efficiently.
While we’re destined to be waiting for supercapacitors to truly step up and solve the energy problem in electric vehicles, it’s good to know that even though we’re currently stuck with Lithium based batteries as a power source, there’s a pretty impressive solution not too far away.