Hi, I’m Ali Sealander with UTD GeoNews and today I want to talk to you about lithium
and how it’becoming increasingly important to our future.
In Sept. 2020, the Governor of California announced that the state would show its commitment
to addressing global climate change by banning the sale of new gasoline-powered cars and trucks by 2035.
We are marking a new course. We are setting a new marker - firm goal that by 2035
In the next 15 years.
We will eliminate in the state of California the sales of internal combustion engines.
In January 2021, President Biden and his new administration has said that they were going to work to completely replace
the entire fleet of nearly 650,000 government vehicles with electric ones. And a few days after that
General Motors made an announcement and said that they were going to
completely phase out all of their gas and diesel
engines by 2035 in favor of all-electric vehicles. But what do these announcements have to do
with lithium? Well, an essential component of electric vehicles is the lithium-ion battery.
And since replacing gasoline-powered cars with battery powered ones would help to reduce the
use of fossil fuels, lithium has now become an essential component to reducing global warming.
The lithium-ion batteries that power electric vehicles are like those that
power your laptop or phone but are scaled up to handle the power demand of an entire vehicle.
The efficiency and recharging capability of these batteries has made them a critical part
of electric vehicles. Even though commercial lithium-ion batteries have been around since
the 1990s they are becoming more important every year.
In the year 2000, the production
of rechargeable batteries consumed only about 5% of the world’s production of lithium,
the rest was used in things like ceramics, greases, and a bunch of other things,
but by 2020 over half went into batteries. This new demand for
lithium is closely tied to the electric vehicle market. To put it in perspective, an electric
car with an 80 kW-hour battery contains about 15 kg of lithium - that’s about
the same weight as 3 gallons of milk. In 2016 the world used 200 thousand tons of Lithium and this
is expected to increase fivefold to well over a million tons by 2030.
Demand is exploding. The California initiative, Biden’s plan, and announcements like General Motor's are following a trend
that’s seeing more and more electric vehicles on the roads and more electric vehicles means
we are going to need a lot more lithium. What is Lithium, anyway? Well it’s an
alkali metal, like sodium or potassium, and is the third lightest element behind hydrogen and helium.
Metallic Lithium is so light it floats on water. Like any metal, it is an excellent conductor of
heat as well as electricity. But you’ll never see lithium in its elemental form in nature.
Like other alkali metals, lithium bonds with elements in rock-forming minerals. It can
be found in igneous rocks and clays, or can be dissolved in brines and seawater. Of these, it’s
the lithium found in igneous rocks and continental brines that are the most economically extractable.
Let’s start with the igneous rocks. Rocks are made up of minerals.
There are thousands of minerals, but just 124 contain lithium, and only a handful of
these contain enough to be worth mining. The most important is the mineral spodumene, with lithium
oxide making up between 6 and 9 percent of the mineral’s weight. So the more spodumene
you have the more lithium that’s available. This is an enormous crystal of spodumene found
in Plumbago Mountain, Maine. Minerals in igneous rocks come
in a wide range of sizes, but when they are large, geologists call the rock a pegmatite.
There are lots of pegmatites all over the world, but only a few contain lithium-rich minerals.
Right now most of the global production of lithium comes from pegmatite mines in Australia,
but Australia doesn’t have the most lithium, far from it,
and in fact, most of our lithium resources don't even come from pegmatites.
66% of global lithium resources can be found in continental brine deposits.
So, what is a brine? Well, a brine is water with a high concentration of dissolved salts.
The most common salt is Sodium Chloride, but there are others, like Potassium chloride, and Lithium
carbonate. Seawater is about 3.5% dissolved salts - anything saltier than that and it is considered
a brine. The brines that are mined for lithium range from about 6% to 84% dissolved salts. To
make lithium brines you need an arid basin - a depression in the land in an area with more
evaporation than precipitation. Water flowing over surrounding highlands leaches lithium out of rocks
and carries dissolved Lithium into the basin. A brine collects in the sediments below the surface
of the basin, where the lithium content becomes increasingly concentrated with time.
These sorts of conditions can be found in and around the Atacama Desert, specifically the
area dubbed the “lithium triangle” that includes parts of Argentina, Bolivia, and Chile. This is
one of the driest places on Earth and beneath the salt flats, or salars, that are scattered
around the area lie the lithium enriched brines. To get the lithium, holes are drilled into the
ground and the salty solution is pumped to the surface. The brines are evaporated in ponds
until all that’s left are the salts, including the lithium. These operations are easier and cheaper
to run than hard rock mining and because of the absolute abundance of lithium resources here
it makes sense that this method of lithium extraction has become increasingly important.
This is how we extract lithium, so I guess the the next question is
when should we expect to run out of it. Will we have enough lithium to power our greener, battery powered future?
To answer this, we need to know how much lithium we expect to use. This is difficult to predict.
One projection we found tied Lithium-ion battery demand to future global GDP growth.
It made a handful of other reasonable assumptions about our future lithium use and it made a
forecast of future use from 2010 to 2100. It projected the demand for lithium to
be about 20 million tons, that’s about the same weight as 4 billion gallons of milk.
As for how much we have, well, every year the U.S. Geological Survey publishes what
is called the Mineral Commodity Summary that includes statistics and information on lithium.
In 2020 this estimated global lithium resources to be around 80 million
tons. Comparing this with the projection of just
20 million tons needed to sustain our demand until 2100 it seems like we’ll have enough.
At the very least we have a good start to meet the growing demand for lithium.
But making long term predictions, especially those related to rapidly evolving technology,
is a fool’s game. Technology shifts, mineral prices vary, recycling capabilities improve,
and even global pandemics are all variables that can effect lithium supply and demand
in ways that cannot be predicted. The increasing desire for electric vehicles is currently fueling
demand for lithium, but what if other applications turn up and prove to be just as sought after?
Products like Tesla’s Powerwall and Powerpack use lithium-ion batteries
to store energy for homes and for commercial use. Tesla announced these in 2015, a few years
after the 20 million ton projection was published. We just don’t know if these and other new uses of lithium
will fuel demand as fast as they do for electric cars, but they might. Or what if new battery
technology emerges that uses much less lithium or even no lithium at all? In fast-changing situations
like these it’s usefull to recall the old adage “all models are wrong, but some are useful”
It’s also important to note that even though lithium mining is a vital part of our efforts
to put less CO2 in the atmosphere, it still harms the environment in other ways.
To produce one ton of lithium you need to mine 250 tons of spodumene, extracting this same
amount of lithium from a brine requires about 500,000 gallons of water.
These operations divert land and water that can be used for other things and also cause pollution that
can, and have, hurt the nearby communities. So we have enough Lithium to
get us through the next few decades as we move towards a greener future, but we’re less confident
about what happens after that. To take Nirvana’s Lithium completely out of context “I’m not sure,
I’m so excited. I can’t wait to meet you there.” See you next time!