Mining activities related to battery minerals
The purpose of mineral exploration is to find and study mineral deposits that could be exploited financially. A financially useful deposit is called an ore.
In Finland, basic geological, geochemical and geophysical data on the Finnish bedrock provided by the Geological Survey of Finland (GTK) is available for mineral exploration companies. Therefore, mineral exploration is usually started by studying this data. An attractive deposit may also be found on the basis of a layman’s sample. Mineral exploration is also steered towards certain areas in Finland by positive experiences in corresponding rock-type areas in the world or the successful and promising findings or existing mining activities in a certain area. One such area in Finland is the Central Lapland region where mineral exploration is carried out actively. Mineral exploration is also targeted at previously known deposits that may even have already been excavated. Usually, the question is that, when global market prices for metals rise to a sufficient level, interest in a deposit considered previously to be unprofitable increases again. These types of areas include the Mustavaara vanadium deposit and the Hautalampi cobalt deposit.
Certain metals can be found from specific rock environments. For example, greenstone zones are favourable for deposits of gold, cobalt, copper and nickel, whereas layered intrusions are ideal for finding chromium, platinum, palladium or vanadium. In Finland, the opportunities for finding lithium are the largest in pegmatite deposits.
Exploration involves great financial risks because effective exploration is expensive, and finding a deposit leading to a mine is very difficult and time-consuming.
During the first phases of exploration, the bedrock in the target area is investigated from exposed segments. Often, test pits are also excavated. The first samples are analysed, and further examinations are determined based on them. Further examinations usually involve soil samples and different geochemical studies. Geochemical studies serve to identify areas where the concentration of certain elements is higher, potentially meaning a mineral deposit.
Geophysical studies serve to determine the electrical, magnetic, radiometric and gravitational properties of the bedrock. Measurements can be carried out using aircraft or in the terrain. Using geophysics, the bedrock can also be studied deeper, and these studies help to identify the composition and structures of the bedrock, as well as the location of specific rock zones.
The aforementioned studies are nearly always carried out before moving on to the drilling stage.
Deep drilling is the most effective method in mineral exploration. It aims to obtain information from bedrock samples taken from deep inside the bedrock by means of diamond drilling. From these drill core samples, the mineralogy can be studied, concentrations can be analysed and, for example, the rock mechanics of the rock can be investigated. In addition, geophysical hole measurements are often conducted from drill holes. They can even be more than a kilometre in length, while they are usually approximately 100–300 metres long. Typically, each metre of drilling costs EUR 100–300.
The results of mineral exploration drilling steer further exploration plans. In the end, only a few exploration sites lead to more extensive studies. If the first results look promising, drilling will be continued. When a deposit can be modelled and found to be feasible for excavation on the basis of drilling, a prefeasibility study will be initiated, followed by a more detailed feasibility study and finally a final or bankable feasibility study. At this stage, plans are already very advanced and profitability has been found to be so certain that the funding of the project can be prepared. Mining permit applications are often prepared at the prefeasibility study stage.
Lithium and mining operations
A mining permit is the prerequisite for the establishment of a mine and the undertaking of mining operations. The mining permit applicant is most often a company registered in Finland, with mining as its line of business.
Lithium does not appear as a pure metal in nature; instead, it is always a compound.
Lithium’s raw material sources include salt water in salt lakes (salt pans), pegmatite deposits and sediment deposits. Lithium is processed into lithium carbonate or lithium hydroxide.
The most important raw material sources of lithium carbonate are salt lake sediments and salt pans. These are particularly found in Chile and China. Before the actual separation process, salt water is pumped up and enriched by evaporating water, usually in large basins under the sun. Finally, the enriched solution is led to a process, in which impurities are removed and lithium is separated.
The world’s largest and purest lithium reserves can be found in the Salar de Atacama salt flats in Chile, which account for half of the world’s lithium.
Pegmatite deposits are another significant raw material source for lithium. These deposits are also called “hard rock lithium deposits”. In addition to lithium, tin, tantalum and niobium can be found from pegmatite deposits. The most common lithium mineral in pegmatite deposits is spodumene (lithium aluminium sulphate). Known deposits of this type are located in Australia, the USA, Canada, Ireland and Congo as well as Finland. Pegmatite deposits are excavated at open-cast mines or underground mines.
Open-cast mining is usually carried out by means of benching. In an open-cast mine, mining proceeds from the top to the bottom, one level or “bench” at a time. Different levels are connected to each other using vehicle routes, or ramps. In open-cast mines, bench height varies from 5 to 20 metres, depending on the mineral. Waste rock also needs to be removed to excavate minerals at open-cast mines. The work phases of open-cast mining are excavation (drilling, charging and blasting), crushing, material loading and transport.
In underground mines, a range of different methods and their variations can be used. The most common excavation methods used in the Nordic countries include sublevel stoping, benching, and sublevel caving.
Sedimentary lithium deposits
In sedimentary rock, lithium is found either in clay deposits or evaporites (water-soluble salt sediments). However, clay deposits have not so far been used in the production of lithium. Possibly the best-known evaporite deposit, Jadar, is located in Serbia.
Mineral treatment and processing
Mineral treatment methods include froth flotation, methods based on density differences, as well as magnetic and chemical methods.
Froth flotation has been the most common treatment method in Finland. The method based on density differences is used, for example, in the treatment of chromite in Finland. Magnetic methods have mainly been used in the treatment of iron ore.
The principle of froth flotation is to produce froth at the top of sludge using flotation chemicals and a strong air flow dispersion, to which removable, or usable, mineral particles adhere as a result of surface tension. Air bubbles can be produced either through electrolysis or by feeding air into the mixture mechanically or by using pressure.
All minerals are hydrophilic and, in froth flotation, certain mineral particles are converted to be hydrophobic by means of collector chemicals, causing them to adhere to the froth for further processing. Regulating chemicals are used to regulate the adherence of collector chemicals selectively to the surface of different minerals. An activator aims to activate the mineral surface for collector chemicals, and a deactivator to deactivate, to remove the mineral from the process. If the purpose of flotation is to remove gangue from valuable minerals, the process is called reverse flotation. After flotation, the valuable mineral material is washed and dried.
Spodumene can be treated, for example, as follows:
First, the ore is crushed. This phase may include optical sorting to remove any waste rock from the ore. The optical sorting of ore requires that the pre-crushed ore is washed or sprayed. The crushed ore is then fed for grinding. Ore grinding is usually carried out using either ball or rod mills, with balls or rods grinding the ore into pieces.
The grinding phase is followed by desliming using hydrocyclones. This is followed by pre-flotation. If required, the pre-flotation concentrate is pumped into magnetic separation to remove the process iron and magnetic minerals from the sludge. After this, the pre-flotation concentrate is pumped into repeating flotation. After the final repeating phase, the concentrate is thickened, filtered and stored for further processing.
Either lithium carbonate or lithium hydroxide can be produced from the lithium concentrate. In the production of lithium carbonate, spodumene can be treated with heat before soda leaching. Before filtering and ion exchange, bicarbonation is carried out. Finally, the lithium carbonate is crystallised.
Production and storage of battery chemicals
Production of battery chemicals
The active components of an electric battery are a cathode, anode and electrolyte. The different battery chemistries of Li-ion batteries are based on the use of different cathode materials. Graphite is commonly used as the anode, while lithium hexafluorophosphate is used as the electrolyte salt and carbonate esters are used as the electrolyte. Cathode materials include:
In accordance with the CLP Regulation, many cathode chemicals are classified as hazardous to health. In particular, nickel and its compounds in powder form may be chemicals that are carcinogenic or suspected to be carcinogenic. Some carbonate esters are classified as flammable liquids. The production of the compounds listed above may involve typical chemical industry processes, such as the mixing of chemicals and the use of strong acids and alkalis, pressure, flammable solvents or heating processes that constitute a fire hazard.
The risks associated with the production of battery chemicals depend on the hazardous properties of the handled and stored chemicals, as well as the conditions in the production process, such as temperature and pressure. The safety of operations is ensured by identifying hazards, assessing the probability of the hazards and the severity of consequences, and determining measures that reduce risks. Companies must be able to prevent explosions and fires at the plant and recover any chemical leaks.
To prevent explosions, potentially explosive atmospheres (such as storerooms for flammable liquids) are identified, and it is ensured that equipment in such atmospheres cannot act as ignition sources.
When storing chemicals, it is ensured that dangerously reacting chemicals cannot come into contact with each other, not even during a leak. Dangerous chemicals are stored in their own designated places, and only the necessary volume of chemicals can be stored in the process area.
Chemical tanks and pipes must be sealed and withstand the impact of the chemicals they contain. Preventive and corrective maintenance ensures that tanks, pipes and other equipment remain in good condition and do not cause any leaks or other accidents.
The volume of dangerous chemicals at the plant determines whether a permit is required for operations and what the supervisory authority is. Plants with larger volumes of chemicals are supervised by the Finnish Safety and Chemicals Agency (Tukes), while smaller plants are supervised by rescue departments. However, both are subject to the same chemical safety legislation. If a plant is under the supervision of Tukes, a chemicals supervisor must be appointed and an internal rescue plan for major chemical accidents must be prepared.
More detailed information on the positioning of a battery chemical plant and on safety requirements is available on the chemical plants pages.
Battery chemicals as products
The production, imports, distribution, use and storage of battery chemicals are regulated in the national legislation and the EU chemicals regulations. The legislation governing chemicals is broad, covering a number of different sectors. The aim of chemical regulations is to reduce health and environmental risks caused by the use of chemicals.
Registration of chemicals, authorisations and restrictions on the use of chemicals
The EU’s REACH Regulation concerns the registration, evaluation, authorisation and restrictions of chemicals. The REACH Regulation imposes obligations on chemicals manufacturers, importers, producers of articles (such as batteries), downstream users and distributors. Parties must comply with the registration and authorisation requirements concerning chemicals, as well as any prohibitions and limitations on the use of chemicals when products are made available on the market, i.e. sold or supplied otherwise.
The main principle of the REACH Regulation is that companies collect information on the properties and uses of the substance they manufacture or import, assess the risks and hazards associated with the substance, determine conditions for the safe use of the substance, and submit the information to the European Chemicals Agency (ECHA) by registering the substance. The registration requirement applies to parties that import a substance into the EU or manufacture a substance in the EU area at a volume of more than one tonne per year. Further information on the obligations set out in the REACH Regulation is available on the Tukes website.
A safety data sheet must be prepared for a dangerous chemical product, and it must be provided for professional and industrial users of the chemical. Safety data sheets are used by chemical suppliers to provide their customers with information about the properties and risks of the chemicals and how to store and handle them safely. Safety data sheets permit users of chemicals to use them safely.
The REACH Regulation prohibits and restricts the use and placing on the market of certain substances (Annex XVII) on their own, in a mixture or in an article. The content of restrictions varies depending on the substance. A restriction may concern, for example, the use of a substance in manufacturing a battery or placing a battery on the market within the EU. The European Commission imposes restrictions on substances if it is considered that a substance poses an uncontrollable risk to human health or the environment.
The REACH Regulation includes a separate authorisation procedure for the use of certain substances (Annex XIV). The authorisation procedure may concern, for example, the use of a substance in manufacturing batteries. A substance subject to an authorisation may only be used if the European Commission has authorised the use of the substance. A substance must not be supplied for uses subject to authorisation, unless this use is authorised. The purpose of the authorisation procedure is to ensure that the risks associated with the use of substances of very high concern (SVHC) are managed (safe use to be demonstrated) and to promote the replacement of these substances with safer substances or methods.
If a battery contains an SVHC, this will set various obligations for companies. SVHCs contained in articles must be reported to the ECHA, and suppliers of articles must provide the recipients of the article with sufficient information to enable the safe use of the battery.
Classification, labelling and packaging of chemicals
The EU CLP Regulation applies to the classification, labelling and packaging of chemicals. Parties must classify, label and package dangerous chemicals in accordance with the CLP Regulation before they are placed on the market. The CLP Regulation mainly applies to substances and mixtures. Warning labels in accordance with the CLP Regulation on dangerous chemicals sold in Finland must be in Finnish and Swedish. Further information on the CLP Regulation.
A chemical notification must be submitted to Tukes regarding dangerous chemicals intended for professional use and for use by the general public. Chemical notifications are required from all businesses that produce chemicals for the domestic market in Finland and Finnish businesses that import chemicals to Finland. Companies must submit a notification in the KemiDigi system.
KemiDigi data is available to the Poison Information Centre via the KemiDigi system. The information provided in chemical notifications is used, for example, to issue treatment instructions for acute poisonings by the Poison Information Centre, to issue preventive instructions, and to investigate occupational diseases and accidents.
Chemical advisory service
Tukes provides a statutory national chemical advisory service, which is designed to educate businesses about their obligations under chemical regulations (the REACH Regulation, the CLP Regulation and the Biocidal Products Regulation).
In Finland, several different authorities jointly supervise companies’ compliance with chemicals regulations.
Transport of battery chemicals
Various chemicals, substances, mixtures of substances, products, even articles containing such individual substances or combinations of substances (= mixtures), the effects of which may be hazardous or harmful when they can come into contact with live tissues, materials, nutrients, feed and other such substances may be considered to be dangerous goods during transport. Environmental hazards must also be taken into account in the transport of dangerous goods.
Some of the raw materials used in battery manufacturing are dangerous substances not only from the perspective of chemicals regulations, but also from the points of view of transport regulations. These include cobalt in addition to lithium.
The purpose of the legislation on the transport of dangerous goods is to prevent and control the damage and dangers that the transport of dangerous goods may pose to people, property or the environment.
The tanks and packaging for dangerous goods must fulfil the technical requirements of the legislation and regulations on transport of dangerous goods (VAK) to ensure that their content does not pose a danger to people or the environment, even in case of accident. Tukes supervises the compliance of packaging and tanks used in transport governed by VAK regulations with requirements. Further information is available on Tukes pages on the transport of dangerous goods.
The legislation and regulations on the transport of dangerous goods are available on Traficom pages on the transport of dangerous goods.
Manufacture and storage of batteries
Manufacture or importing of batteries and battery cells
Battery cells consist of an anode, cathode and electrolyte, which are enclosed in a sealed packaging. The packaging may be a flat bag made of a foil or polymer (e.g. smartphones) or a steel cylinder providing a higher level of mechanical protection (e.g. 18650 type cells that are common in electric car batteries). The packaging must be airtight to keep the electrolyte inside it and, for example, oxygen and moisture outside the battery.
In the manufacture of the anode and cathode (electrodes), pastes are mixed from a solvent, binder, and anode and cathode materials. The pastes are spread on metal foils and baked in an oven. During baking, the solvent evaporates and leaves a porous structure in the electrode material. When using a dangerous chemical as a solvent, it can be recovered and recycled. The porousness of the electrode can still be modified by means of calandering.
The electrolyte is mixed from carbonate esters and salt (e.g. lithium hexafluorophosphate). The anode and cathode strips are folded, with an insulating film between them, inside the packaging, the packaging is filled electrolytes, and the electrodes are connected to the battery terminals. The packaging is then sealed. The process involves the handling and storage of several dangerous chemicals. See “Production and storage of battery chemicals”.
When manufacturing batteries, it should be ensured that there is as little flammable material in the vicinity as possible during production, and if possible the battery handling line should be equipped with a sprinkler system.
The manufacturer, importer or seller of batteries must ensure that batteries are furnished with the necessary labels: separate collection, capacity and, if necessary, chemical labelling (Hg, Cd or Pb). Restrictions on the use of mercury and cadmium must also be taken into account. The manufacturer or the company importing batteries into Finland must also remember the obligations concerning producer responsibility.
Batteries involve the risk of thermal runaway and the spread of a fire to surrounding batteries, other fire loads and ultimately the entire building. Moving batteries around involves the risk of damage and thermal runaway, for example, when a battery falls down or is dented. Used batteries and batteries found or suspected to be defective must be kept separate from new ones. This reduces the risk of the spread of thermal runaway from defective batteries to unused batteries.
It is recommended that batteries be stored in their own fire compartment or in a clearly limited area in a storage space (e.g. in a separate fireproof cabinet, separate from fire loads). No significant amounts of dangerous chemicals, especially flammable liquids or gases, should be stored in the same fire compartment with the battery storage.
In a shelf storage, an overhead sprinkler system is not sufficient to cool a large number of batteries, which is why shelf-specific sprinklers are recommended. Building supervisors may require an automated fire extinguishing system in the building permit or in a permit for changing the building’s purpose of use. If building supervisors do not require such a system, the company in question can still install one on the basis of its own risk assessment. Insurance companies can also issue recommendations for fire protection.
During storage, the magnitude of risks is increased, in particular, by the large number of batteries, the amount of the fire load near the batteries and any storage of cells or batteries with their terminals unprotected. Fire loads include the packaging of batteries or cells, fixtures in storage facilities and other products being stored. Unprotected terminals may expose the battery to external short-circuiting. The physical size of batteries is also a significant factor, as moving large batteries around is either impossible or slow in the event of a malfunction.
Order, delivery and storage processes should be planned so that the organisation in question is always aware of where Li-ion batteries are at all times.
Li-ion batteries contain cathode materials and electrolytes classified as dangerous in accordance with the CLP Regulation. However, the REACH and CLP Regulations do not apply to articles from which chemicals are not intended to be released during their intended purpose of use. Li-ion batteries are considered such articles (exemptions include articles containing SVHCs). As a rule, storage is not regarded as an activity subject to a licence as defined in the Act on Chemical Safety, even in large quantities, and batteries do not need to be furnished with hazard labels in accordance with the CLP Regulation.
The storage of batteries in new buildings is supervised by the building supervision authority, which can request a statement from the rescue authorities. If the storage of a significant number of batteries is started in an existing building, the need to apply for a change in the purpose of use of the building must be investigated. The rescue department supervises fire safety during use by means of fire inspections.
Transport of batteries
Batteries are dangerous articles from the perspective of transport regulations. Li-ion batteries are always classified as dangerous during transport, and the air transport of some batteries is even forbidden. Transport regulations applicable to batteries depend on the battery technology, capacity and whether they are transported as part of equipment, with equipment or as separate batteries or separate cells.
The purpose of internationally harmonised regulations on the transport of dangerous goods is to minimise the risks associated with dangerous goods and to ensure that, even in case of an incident, the potentially dangerous properties of the load are known and it is possible to prevent major damage in the event of an accident. The reactivity of Li-ion batteries, how they behave in a fire and how difficult they are to extinguish are reasons why batteries must be packaged, labelled and reported in accordance with regulations on the transport of dangerous goods.
More information on regulations on the transport of dangerous goods is available in the Transport of battery chemicals section.
Sales of batteries
The charge of batteries is a key safety factor when selling batteries. Fully charged batteries should not be kept on the shelf, because risks increase if several batteries are stored in a small space. Similarly, batteries should not be stored empty, as the internal structure of batteries may be damaged so that they can no longer be charged. A battery may also be damaged when charging attempts are extended, which means that, in the worst case, the battery may ignite.
Batteries available for sale must not contain any mercury or cadmium. Exceptions include emergency and alarm systems that may include batteries containing cadmium. So far, there are no restrictions on the use of lead in batteries, while lead batteries must be furnished with the chemical symbol of lead (Pb).
Batteries available for sale must have a separate collection label and labels indicating the capacity of the battery. The separate collection label is closely linked to the obligations of producer responsibility, the fulfilment of which must be ensured by the company importing batteries into Finland.
Use of batteries
Using batteries in electrical systems
Battery systems consisting of several battery modules are used, for example, to store renewable energy (solar power), to balance peak loads or as a reserve for disturbances. They are used, for example, as part of electricity distribution networks and in industries.
As the production of renewable energy is increasing and the prices of batteries are decreasing, they will, to a significant extent, be introduced in shopping centres and office buildings, as well as multi-storey buildings and terraced and detached houses. In addition, electric vehicles connected to a charging station can be used for storing energy.
If necessary, a battery system can be guided with different control systems to supply power to certain equipment, such as a water heater, or programmed to discharge and recharge at a specific time, for example. Batteries can also be controlled using smart devices.
Key risks in the use of batteries as part of an electrical system are related to electrical safety. Electrical work involving installations that include batteries must address that, due to the battery system, some installation components may be live, even if the main switch is turned off. Therefore, special attention must be paid to ensuring and verifying that the installation is discharged.