Lithium-Ion Batteries

I thought it would be good to delve deeper into this technology. There are in fact three types of batteries using Lithium. There’s the straight Lithium battery – those small round batteries used in clocks, watches etc, the Lithium Ion battery and the Lithium Ion polymer battery. I’ll discuss the last two as they are related when it comes to car usage.

A Swedish scientist, Johan Arfwedson, discovered the element lithium in 1817 and it was a chemist at the Exxon oil company that came up with the concepts of a Lithium Ion battery during the 1970s whilst looking at the properties of materials. It was found that Lithium with graphite was an exceptional conductor that could be reversed. In other words, it could drain and recharge easily. Bell Labs were the first to develop a modern Lithium Ion battery by covering both the anode and cathode of the battery with a surface that contained lithium ions.

The anode of a battery is the electrode through which the electric current enters the device whilst the cathode is the opposite – it is the way that the electricity leaves the device. Ions are atoms or molecules that have lost or gained an electron thus creating an electric charge.

There is one other important factor about Lithium Ion batteries – they are “secondary” batteries. This means that they can be recharged – ordinary Lithium batteries like the ones in a watch are “primary” batteries, they are designed to be used only once and therefore disposable when fully used. It was Sony in the early 1990s that released the first commercial Lithium Ion battery and this was the start of the use of them in consumer electronics.

The great thing about Lithium Ion batteries is that they can be manufactured in different shapes, which means that designers can make them to suit the product shape – that’s why nearly every mobile phone battery is different! The batteries also don’t have a memory effect, something that affected earlier style batteries where they would remember the typical usage and only charge to that state. This would gradually increase until the battery needed a complete overhaul.

Lithium Ion batteries do, however, have a similar problem – not memory based but age. They typically lose some of their effective capacity each year they are on the planet – in other words this starts from time they roll off the production line. This is probably why organisations like Tesla and the old Better Place (now liquidated) factored in battery replacements as part of their recharging networks. Hopefully all car batteries will be manufactured the same way and to the same shape. We must surely have learned something from mobile phone design!

One of the good things about the Lithium Ion battery is that because it has such a wide range of uses, there are many companies researching new technologies and ideas to extend their usage and life. This can only be good for the car industry as they become more widely used in the many hybrid and fully electric cars now for sale.

Earlier I spoke about the Lithium Ion polymer battery. Both the original Lithium Ion and the polymer batteries are being used by car manufacturers in their electric models and future prototypes. The polymer batteries differ in that the electrolyte used, being a lithium salt in the Lithium Ion battery, is encased in a polymer to make a flexible strip. This improves the robustness of the battery. It is the electrolyte that transfers the electricity from the anode to the cathode. In other words, it’s the transport layer. Whereas most car companies are using the Lithium Ion battery for their development, Hyundai believes that the polymer battery is the way to go.

So to finish off, Lithium is a natural compound found in clays and other natural substances. It is found all over the world and the boffins have worked out that it formed during the big bang that was the start of life as we know it. The problem is, most of the Lithium is in a very poor state that requires expensive processing to extract and make usable.

I can see that Lithium will become the next major global political fight alongside water as our dependence on oil slowly declines. Remember as the price of oil rose, so too did the extraction of oil from hard to get places because it became viable to do so. If the countries that have the largest reserves force the price of Lithium too high then they will lose market share as other areas become viable to mine and process.

I would hope that we learn from the oil market and do not allow one or two countries to dominate the market and we do not get another OPEC style group that tries to dictate pricing. Lithium is clearly a an important mineral for the future of travel, productivity and entertainment.