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Skip to 0 minutes and 9 secondsHello. My name is Yann Laot. I'm working at Saft, a battery company part of group total, a french oil and gas major Let's start by the core element of a battery, the cell. If many shapes and sizes are possible, the operating principle is still the same. Upon charge and discharge, lithium atoms split into lithium ions and electrons. Lithium ions are migrating between the two set of electrodes, while the free electrons circulate through the external circuit giving or capturing energy. As such, lithium is a critical element to allow lithium ion cell to operate. But lithium alone is far from being sufficient, and it's potentially not the main limiting factor, as we'll see.

Skip to 1 minute and 0 secondsA cell is made of three main successive layers. On one hand, a metallic current collector, generally made of copper at the negative electrode, is coated with a layer of active material, usually natural graphite mixed with some polymer binders and other chemical additives.

Skip to 1 minute and 21 secondsOn the other hand, another metallic current collector, generally made of aluminum, is coated with a layer of active material, usually a mixture of transition metals such as cobalt, nickel, manganese, iron, and/or aluminum. The material is mostly found in oxide of phosphate crystal. In between, a polymer separator made of one or multiple layers of poly-ethylene and/or polypropylene. This membrane is sometimes coated with a protection layer made of a ceramic. Overall, it prevents the two electrodes to get into contact and to react in an uncontrolled way.

Skip to 2 minutes and 7 secondsThose three layers are wetted by a liquid, an organic solvent, including some lithium and fluorine-based salts. This liquid mixtures increases ionic connectivity and thus allows lithium ions to move more efficiently through the active material and through the separator. The combination of those three layers forms what we call a jelly-roll or sometimes a stack, which is then inserted into a metallic can or into a polymer and metallic pouch.

Skip to 2 minutes and 41 secondsBottom line, a lithium ion cell is a complex object made of many chemicals elements, ranging from metals and non-metals to polymer and organic solvents.

Skip to 2 minutes and 54 secondsTwo side notes. First, if some of the metals mentioned before can be rare, such as cobalt, it should be noted that lithium-ion battery usually doesn't include any rare earths such as niobium, tellurium and others that are found, for example, in many high performance magnets. Second, it should be noted that lithium-ion is a broad family made of various sub-chemistries and may include many other elements than the ones mentioned from titanium, silicium, tin, antimony, to even pure metallic lithium.

Skip to 3 minutes and 31 secondsWhat is high level composition of a lithium ion cell?

Skip to 3 minutes and 36 secondsLet's use a concrete example. A large pouch cell made of graphite at the anode and of NMC111 at the cathode. NMC111 means that nickel, cobalt, and aluminium are in equal parts in the active material. This chemistry is typically used in current electric cars and stationary energy storage solutions. In terms of weight, a best-in-class cell of 70Ah at 260 watt hour per kilogram would then weigh almost one kilogram. Out of that, 91 g would be lithium, 232 g cobalt, 231 g nickel, and 216 g manganese. Active materials would thus represent 70% of a cell mass, only 9% of it being lithium. What is the supply chain? First the metals.

Skip to 4 minutes and 27 secondsEach metal is first mined then refined into precursors at a technical grade suitable for batteries. Then various metals are chemically reacted together, for example, for ball-milling to form the active material. This active material is finally mixed, with additives such as graphite, polymer binders, and solvents to form a slurry or an ink that will be coated and dried oanto metallic collector to form an electrode.

Skip to 4 minutes and 56 secondsNatural graphite is also a key component, coming from mines before being purified, and then chemically modified to enhance its properties.

Skip to 5 minutes and 8 secondsOther materials, polymer, additives, and organic electrolyte, come from usual specialty chemistry industry.

Skip to 5 minutes and 19 secondsOverall, some of the materials present in our batteries made one or two or even three world trips before being the final battery delivered to a customer.

Skip to 5 minutes and 31 secondsShortening the supply chain is a key challenge for all stakeholders to decrease costs, to improve ecological footprint, and supply chain resiliency.

Skip to 5 minutes and 44 secondsWhere do those materials come from? A significant part of lithium is mined out of Salars in the ABC triangle in South America, Argentina, Bolivia, and Chile. Those three countries represent about 50% of worldwide proven reserves and offer easy to collect and naturally high grade lithium salts. versus just hard rocks coming from China, Australia, USA, and others. The purifying process is consuming water, and many technology developments are ongoing to improve ecological footprint. Today around 50% of worldwide refining capacity is located in China.

Skip to 6 minutes and 28 secondsCobalt is a pretty specific resource. It's almost exclusively mined as a by-product, mainly from nickel. It requires extensive refining and purifying to have a suitable grade for batteries. Moreover, Democratic Republic of Congo is a central stakeholder of its metal, holding more than 70% of the worldwide known resources and 50% of the current supply. Today around 80% of the worldwide refining capacity is located in China. Ensuring an ethically responsible supply chain is a challenge for all the actors of the value chain. The case of cobalt is very sensitive, particularly because cobalt cannot be laser-marked or traced, as for example are diamonds.

Skip to 7 minutes and 20 secondsFinally, nickel, manganese aluminium, copper, and natural graphite are mined all around the world in various places and are less prone to geopolitical issues in terms of sourcing.

Skip to 7 minutes and 37 secondsAre there enough resources to sustain the energy transition? Proven reserves of lithium are estimated to be 30,000 kilotons of lithium metal equivalent. Resources are estimated to be at least 60,000 kilotons. Current consumption of lithium, which half of it goes to lithium-ion battery, is 35 kiloton per year. So at the current rate, we can then estimate that we have about 1,000 years of consumption in front of us. Nonetheless, the EV market is relatively small as of today, and its gross could change the picture dramatically. Let's assume we convert overnight into EVs one billion light duty vehicles, which is about the current worldwide fleet.

Skip to 8 minutes and 24 secondsWith a 40 kilowatt hour pack hypothesis we would have on average three kilograms of lithium metal per vehicle, versus 3,000 kiloton or 1/10 of the world proven reserves for the whole fleet. So lithium reserves are not unlimit. Nonetheless, it's still significant and the implementation of a closed-loop recycling will be a must-have to ensure the sustainability of this industry.

Skip to 8 minutes and 50 secondsCobalt is scarce. Only 7,000 kiloton of proven reserves, with probably 120,000 kiloton of resources. The same 40 kilowatt hour EV pack would consume from 2.5 to 5 kilogram. 1 billion EV would thus consume 5,000 kiloton, 70% of worldwide proven reserves. Finally, the consumption of nickel, manganese aluminium, copper, and natural graphite for lithium-ion battery is less significant versus our primary usage or versus variable reserves. It's for example, the case of nickel, which is driven mainly by stainless steel business. Nonetheless, the growing demand for batteries may have a non-negligible impact on forward prices.

Lithium-ion batteries supply chain

What is the core element of a lithium-ion battery? What does the supply chain for large-scale battery production look like? Won’t we run out of resources when trying to achieve the energy transition? Yann Laot, Strategic Marketing Manager at SAFT answers all these questions!

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Understanding Energy Storage: The Battery Revolution

EIT InnoEnergy