Electric vehicles currently make up a very small proportion of most national car fleets. In Australia it is less than 1%. In Norway however, over 50% of new vehicles sold are electric or hybrid. EV’s (Electric Vehicles) have less maintenance than ICE (Internal Combustion Engine) vehicles. EV’s generally have 18 moving parts versus the incredible complexity of today’s ICE vehicles therefore are cheaper to maintain. EV’s are non polluting (depending upon how the power is originally generated) and have more torque (better pulling power so better for trucks, busses and other vehicles that carry significant weight). So what will power all the electric vehicles of the future and can we solve range anxiety (the fear that you will run out of power and not be able to recharge)?
Today I will outline 3 approaches to powering electric vehicles. All work, however one will eventually be proven more reliable, faster to charge, longer lasting and more flexible than the others. For those of you old enough, it is the VHS v Betamax debate (if you are not old enough to know what I am talking about, google it and learn some history).
Lithium-ion Batteries
There are 5 main types of Lithium-ion batteries. Each has advantages and disadvantages over the others.
Lithium cobalt oxide batteries are used in consumer electronics as they are very stable however they have lower capacity. It is also one of the most expensive types and vulnerable to overheating and outgassing (releasing gasses trapped during manufacture).
Lithium-ion manganese oxide is an inexpensive alternative which uses a spinel structure (Octahedral Crystals) which allows for a higher rate of charging however they have a lower overall capacity. This is a newer technology which is still evolving.
Lithium iron phosphate batteries use carbon anodes and heat to extract the power from the lithium. It has 25% less capacity but does not have the same safety concerns and lasts up to 5 times longer, however the cost is higher.
Lithium-titanate oxide is a quicker charging battery however it supports lower voltage and lower capacity.
Lithium-sulfur is a new type of battery which is relatively light, has a higher energy density (2 to 3 times higher) and lower costs.
Each type of battery has a trade off of, charging speed, capacity, cost and other features. One will eventually prove more useful and the market will determine which.
Is there an alternative to the single large battery?
Tanktwo a Finnish-American startup that is developing a small ball shaped battery.
Essentially the fuel tank is filled with as many of these balls as required to power an electric vehicle. If you have a trip of 100 kilometers then you only need to take as many balls as necessary to drive 100 kilometers. This saves on weight and overall cost. The tank can be emptied and refilled in approximately 3 mins.
This type of technology will most likely be used by fleets that have fixed duration trips. For example a garbage truck that runs the same route each day. Fill each trucks’ tank with as many balls as required rather than using large fixed size batteries that have more capacity and weight than required. If the truck needs to take a longer trip, add a few more balls. The batteries last longer and give fleets greater flexibility and reduce the overall cost in powering the fleet.
Are there any alternatives to current technology batteries?
Dr Donald Highgate was the inventor of the extended wear contact lens. This lens is a complex polymer than has specific properties that allow it to be worn for long periods and to function as a lens for better sight. More recently he has applied his knowledge of complex polymers to developing a “supercapacitor” capable of holding charge for powering electric machines.
Research began in 2014 and in June 2018 the first chemically stable, non-metallic pouch cell devices were built. The mission is continue development of high energy density storage devices that have low cost. These devices will be faster charging, longer lasting and lighter than current battery technology. Their materials have capacitance values of between 1,000 and 10,000 times higher than existing aqueous electrolytes in supercapacitors. Their commercial development timeline is as follows:
Whr/kg is watts per hour per kilogram of weight. Batteries need high storage for longer at a lighter weight to be more effective. Using this new technology it currently takes the same amount of time to recharge as it takes to fill a car’s fuel tank for the same distance to be driven. This will only improve. More information is available on their website.
The supercapacitor advantages are: rapid recharging, very long life, safe, no rare elements (so cheaper), very light weight, high cycle efficiency and a wide operating temperature range (lithium based batteries have problems at lower temperatures).
There are no doubt many other new and better technologies being developed in Universities and Research Labs around the world.
Paying it Forward
If you have a start-up or know of a start-up that has a product ready for market please let me know. I would be happy to have a look and give the start-up a shout out to my readers if it is something that I think they could use. If you have any questions or comments please email me via my website craigcarlyon.com
Till next week.