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Because of its name, lithium-ion (li-ion), people think that li-ion batteries are primarily made of lithium and that if we transition the world’s car fleet to electric, it will create a supply problem. While it’s certainly true that lithium demand is expected to rise significantly, which is why the price has spiked recently, the resource is abundant and production can keep up with the right investments.
But it would be a mistake to focus only on lithium. There are several other raw materials in batteries and they each can create bottlenecks if not properly addressed. We will look at an example with a Tesla Model S battery pack through an infographic embedded below.
Tesla has been signing supply contracts with a few potential new lithium sources and even reportedly tried to purchase a lithium startup. That’s something that can help the mining companies secure investments to exploit those new sources, but again lithium is not the primary issue.
It is estimated that there’s about 63 kg of lithium in a 70 kWh Tesla Model S battery pack, which weighs over 1,000 lbs (~453 kg).
When asked if he worries about lithium supply, Tesla CTO JB Straubel once said that he worries more about cobalt, which is used in the cathode of Tesla’s battery cells. The resource is more problematic since the bulk of it overall supply has historically come from the conflict-prone Congo, but new sources are being explored in North America.
Tesla has stated the goal to try to prioritize sourcing raw materials in North America for its Gigafactory in Nevada, where the company will produce its new ‘2170’ battery cells. Tesla and its battery cell partner, Panasonic, have yet to reveal the chemistry of its new cell, but it’s not expected to be dramatically different from the current chemistry.
Therefore, it’s still valuable to explore the current raw materials in its batteries and keep an eye on the status of the resources. Tesla expects to produce 35 GWh worth of batteries in 2018, which is equivalent to the entire world production in 2013. That’s a 100% increase from a single factory.
Visual Capitalist published a breakdown of raw materials in popular li-ion batteries in order to help identify possible bottlenecks:
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