Land, sea and air

By July 7, 2019Technology

Back when I was a kid there I knew of two types of rechargeable batteries; charged batteries and flat batteries, for all were variations on the lead-acid battery. The Lead-acid battery was invented in the middle of the 19th century and is still in use today. These days they are mostly used to start internal combustion engines or to power short range vehicles like golf carts, forklifts, stockpickers etc.1

There are many parameters which are used to describe batteries, ranging from recycling capability, cost of raw materials, functional safety, cost per kilowatt hour, and energy content (also called specific energy or gravimetric energy density: i.e. Watt hour per kilogram [Wh/kg]). Lead-acid batteries have an energy content of usually less than 40 Wh/kg.1

The next lot of rechargeable batteries which appeared on my horizon were used to power winches and the rudder on my radio-controlled M-class racing yacht. These batteries were colloquially called NiCads, or Nickel-Cadmium batteries. There were a series of Nickel-based batteries, including Nickel-Zinc, Nickel-Iron and Nickel-metal hydride types. The specific energy of Nickel-Cadmium batteries was an improvement over that of Lead-acid batteries and ranged from 50-60Wh/kg. The improved Nickel-Zinc batteries had a specific energy of 80-100Wh/kg2. These batteries are used in power tools because they keep up a steady voltage until they are almost discharged, unlike other batteries which decline in voltage well before they are completely depleted3.

Lithium Ion batteries, are in fact a Lithium-Cobalt-Oxide battery, as its predecessor, the Lithium metal battery had a habit of bursting into flames. The Lithium ion battery was patented in 1991 and they are used in all sorts of devices: mobile phones, computers, and now vehicles. They have a much greater specific energy than the preceding Nickel-Cadmium version and the battery in your mobile phone can have a specific energy as much as 250Wh/kg4,5.

250Wh/kg model 2170 batteries are those used in Tesla cars, particularly the new Model 3 which is being released next year. Tesla expects to be able to push Lithium ion batteries to a specific energy of 330Wh/kg, and the US Department of Energy, as well as several European universities and other agencies are funding programs to push that to 500Wh/kg6,7. Now, a Swiss company, Innolith, claims to have made the world’s first 1,000Wh/kg Lithium ion battery. A battery with that specific energy would be capable of powering an electric car for 1,000km, given their current battery size. Currently, electric cars are able to travel a little over 500km on a single charge.

While the idiots in the Coalition parties whined about electric vehicles during the election campaign8,9,10,11, and pretended they would lead to the decline of civilisation, or at least the weekend, and would never amount to anything, the reverse is true. They may actually assist in mitigating the worst depredations of climate change, if it is not already too late. The batteries available now can already allow you to travel in an electric car as far as a fossil-fuel powered car can on a tank of petrol. If Innolith’s battery or indeed any of the other improved batteries comes to fruition, then anyone who drives a fossil-fuel powered car then will be looked upon as a retro curiosity or an environmental vandal. Indeed, the modern batteries already on the market are so powerful that they are not only powering cars, but trucks12  and now aircraft13, including helicopters14. Numerous companies, including some major manufacturers are investigating the possibility, with some aircraft having already flown and some expected within the next couple of years. I wonder what the halfwits in the Coalition government will believe is at risk because of this. Air travel? Cruise liners? Clouds? Pigeons?




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