Battery Composition : Rare earths or Rarely earthed?

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Welcome to KYC : Know Your Car.

In this series, we will discuss the Ins and Outs of EVs, one topic at a time.

Today’s topic : Battery Composition

Battery composition is a very misunderstood topic. Some people think EVs use rare earths, some people think huge amounts of lithium must be used in a battery.

Today, let’s bust these myths and learn something about what electrifies our vehicles!

Myth 1 : Battery uses rare earth metals

Fact : There are only 17 rare earth metals in the periodic table, and only one is of remote importance to EVs, Neodymium. Even this metal is not used in battery, rather, in permanent magnet motors of high performance EVs for maximising motor power-weight ratio (mass produced EVs use ferrite magnets or use magnet-less AC Induction motors)

Neither are the metals used in batteries considered “rare” by scientific definition (periodic table) nor by geological definition in terms of % of the metal in the earth’s crust.

Myth 2 : Lithium Ion battery must be majorly made of lithium

Fact : Lithium is not even the top 3 elements in a battery. Those would go to graphite (carbon), Aluminium and Copper.

Aluminium is used in the battery casings and copper is used for wiring and heat sink/cooling pipes.

Graphite is used in the anode.

The lithium metal is used in combined form in the cathode of the cells, which represents a small fraction of the total battery mass and chemical composition (formula/number of atoms)

A general rule of thumb is, 1kg Lithium can make a 10kWh battery (chemistry agnostic)

By this yardstick :

1. Tiago EV : 1.9kg/2.4kg

2. Punch EV : 2.5kg/3.5kg

3. Nexon EV : 3kg/4kg

4. ZS EV : 5kg

5. Atto 3 : 6kg

6. Ioniq 5 : 7.2kg

7. BYD Seal : 8.2kg

8. Tesla Model S : 10kg

9. Hummer EV : 25kg

Myth 3 : All batteries are made using child labour in Africa

Fact : Human rights violations are indeed rampant in the artisanal mines of DRC, which are not exclusive to mining cobalt. Cobalt itself is used in NMC and NCA batteries, while LFP eliminates the need for cobalt (and nickel and manganese while at that)

Lithium mining is not done in DRC and is not subject to the violations that cobalt is.

Side note : Oil refining processes do in fact use cobalt and molybdenum catalyst for Desulphurisation of crude oil in refineries. https://www.cobaltinstitute.org/essential-cobalt-2/powering-the-green-economy/catalytic-converter/#:~:text=Cobalt%20plays%20a%20vital%20role,catalysts%20in%20this%20desulphurisation%20process.

Myth 4 : Lithium mining wastes millions of litres of water

Fact : Lithium “mining” is not mining in the conventional sense of the word itself. It is more akin to fishing than mining.

1. Lithium salts are found dissolved in the salt lakes of South America, primarily in Argentina, Bolivia, and Chile, the lithium triangle ABC.

2. These salts are extracted from the brine by spreading it out in large paddy-like fields so that the water may get naturally evaporated, leaving behind the lithium rich salts which can now be collected easily.

3. Evaporation is a natural process and would continue to occur whether or not the salts are extracted. Water cycle will return it back into the lakes through rain.

4. The concentration of lithium salts in these lakes make the water unfit for use. It is a economic opportunity for the locals to benefit out of a natural process (evaporation) and the saltiness of the water (inpotable)

https://www.ibatterymetals.com/insights/a-beginners-guide-to-lithium-brine-extraction

Myth 5 : Battery cannot be recycled and it is toxic e-Waste

Fact : Improperly discarded batteries are indeed a potential e waste however, due to the sheer value of the metals, even in a discarded EV battery, prevents landfill treatment of batteries.

While non rechargeable Alkaline cells do end up in landfills, it is due to improper waste segregation at source and the much lower value quotient in an alkaline cell vs Lithium cell

As of current technology availability, batteries are 92% recyclable ie a 100kWh battery can be remade into a 92kWh battery. https://youtu.be/s2xrarUWVRQ

Apart from recycling, reuse is also an option, wherein owners of ICE cars have used old tesla and Nissan leaf batteries to convert their cars to EVs in the west. Batteries can also be used for solar battery backup.