By Helena Laavi
Electric cars and Lithium-ion batteries are rushing to the market, but what is needed to manufacture batteries in Finland?
To manufacture batteries, or more precisely to manufacture the most desired Lithium-ion batteries in Finland, the basic conditions for the manufacturing industry must be met. First, raw materials i.e. valuable minerals such as nickel, cobalt, and lithium, must be sufficiently available like we have it here in Finland, either from our own mines or from the rest of the world, without competitors buying up all the mineral reserves. Next, the min
erals must be refined into suitable chemicals and salts, which for nickel and cobalt typically mean sulfates and for lithium, carbonates, or hydroxides. If these chemicals are available, the necessary battery materials such as precursors, cathode active materials, and anode active materials can be prepared. These can be used to make actual battery cells, which still need to be processed and packaged to standardize the quality and durability of the batteries. Last but not least, we must not forget the stable conditions offered by Finnish government in terms of energy, staff, logistics, and politics.
The manufacture of batteries is not too complex, but it involves electroCHEMISTRY, of which understanding is mandatory. Process conditions do not require extremely high temperatures or pressures, but there are precise specifications for the manufacturing facilities, as impurities and solvent residues spoil the quality of the product. At Chemitec, we have been advising battery and mineral partners for years, so we possess the expertise.
What is needed for batteries?
Hardly anyone will start manufacturing lithium-ion batteries to a greater extent unless there are markets and applications to use the batteries. From Finland, we can easily transport the batteries for prominent European car manufacturers if your production outgrows Finnish market. Life cycle analysis must also be considered because after the actual service time of the battery the used batteries should be recycled in order to save natural resources and prevent pollution.
Precursors are used to make the cathode active material. In the manufacturing, it is extremely important that no impurities enter the mixture. The final product is paste-like.
Cathode active material
Typically, the cathode active material is chemically a metal oxide powder and a mixture of lithium and other metals. Cathode active materials have names such as NMC (Ni, Co, Mn), NCA (Ni, Co, Al) or NMCAM (Ni, Mn, Co, Al, Mg) based on the elemental composition of the material. This is a sensible naming method, as the composition of the cathode active material largely determines the properties of the cathode.
With a cathode, i.e. the positive electrode, aluminum is used as a current collector in Lithium-ion batteries, on which a layer of the active material is attached. The anode, i.e. the negative electrode, uses copper as the current collector and graphite-based starting materials including sometimes also Silicon.
The electrolyte transfers the ions between the electrodes. In Lithium-ion batteries, organic carbonates such as ethylene carbonate or lithium hexafluorophosphate (LiPF6) are used as electrolytes.
Thin films, typically made of polyethylene, polypropene, or nylon, are used as a separator between the electrodes.
Battery cell manufacturing process
The manufacture of battery cells consists of many steps that vary slightly depending on the type of battery being manufactured. Initially, precursors are prepared that are used for coating the electrodes. Other necessary materials such as electrolytes and insulating films are procured so that the batteries can be assembled and finally finished.
Batteries can be roughly divided into three different types of construction: cylindrical, prismatic and pouch-like. The stacking of a cylindrical “finger” battery and a prismatic “box” battery is based on the rolling of successive layers of cathode, anode, and separators, while the pouch-like battery structure resembles a stack of sheets. As the stack is encapsulated and the electrolyte is injected in the basic elements of the battery are put in place.
The cells still need to be finished before they can be used. Initially, the batteries receive an electrochemical treatment that gives the battery the right crystal structure. Any gases formed are removed. The batteries undergo then ageing process to ensure the quality and durability of the batteries. Once the batteries have been tested and packaged, they can be shipped to customers.
What does this all cost?
The price of a Lithium-ion battery is, of course, affected by the characteristics of the battery, which include the battery size, energy density, power, durability, and operational safety. The manufacturing costs of an NCM-based electric car battery is probably around 160 € / kWh, of which only the battery cell manufacturing costs are 80 € / kWh. The most significant role in the production costs of a battery cell is played by the production of cathode active material, which causes more than 40% of the production costs of cell materials.
If you have planning to start Lithium-ion battery manufacturing do not hesitate to ask more details from our experts!