Manganese sulfate is a key material component of some lithium-ion battery chemistries, particularly nickel, manganese, cobalt (NMC) cathodes, providing stability to the cathode during cycles, enabling greater range.
In this series, which will comprise of three parts, Fastmarkets will explore the current market dynamics in manganese sulfate markets, as well as future applications and battery chemistries.
Like many battery raw materials, manganese metal (which Fastmarkets prices as electrolytic manganese flake) consumption has historically been dominated by the alloy steel sector rather than lithium-ion batteries. Part of the reason that battery grade manganese does not often dominate discussions in the battery raw materials market is due to its apparent abundance of supply, though it is highly concentrated in China.
Part of the reason that manganese does not often dominate discussions in battery raw materials is due to its apparent abundance of supply, though it is highly concentrated in China.
Other regions are expected to see production growth, but China’s dominant position is likely to remain unchanged by the end of the decade.
There is a growing expectation though, though due to complexities around production and significant growth in demand that regional price volatility could quickly emerge.
Furthermore, although manganese is largely abundant, not all of the product currently mined or refined is suitable for battery grade material.
“[The manganese ore] needs to be soluble, preferably a carbonate ore,” Euro Manganese commercial vice president James Fraser said when speaking to Fastmarkets earlier this year, “or else it needs to be roasted to make it soluble (as is the case for most oxide ores).”
“Most ore is in oxide form; carbonate ores are much rarer,” Fraser added.
Tight availability of appropriate ore is not the only challenge facing the manganese sulfate industry though, with participants highlighting the challenge around refining/processing bottlenecks outside of China.
“Outside of China, very few countries produce manganese sulfate, and currently only one country has battery grade manganese sulfate production,” Manganese Metal Company (MMC) chief marketing office Madelein Todd said.
This is evidenced by data from the International Energy Association in its recent report on critical raw materials, which states that 97% of battery grade manganese sulfate is produced in China.
Considering these potential production bottlenecks, participants highlighted the multiple methods of production available to producers.
Manganese ore and manganese metal can all be used as a feedstock in the production of manganese metal. However, each requires different approaches.
From ore, the manganese is leached, purified and then crystallized in high purity crystals which can then be used in the process of manufacturing manganese sulfate.
“Alternatively, the ore is put through electrowinning by which electrolysis is used to extract the metal from a purified leach solution and shipped to a pre-cursor maker, which would dissolve it in sulfuric acid,” Todd said.
Instead of using manganese ore though, sulfate producers can use manganese metal. Sulfate producers can take manganese metal and dissolve this in sulfuric acid to form manganese sulfate which can be crystalised.
This route involves less processing and can also result in higher purity of material, according to sources.
However, both methods are tried and proven as effective in producing manganese sulfate, and as the market develop, Todd believes the choice of feedstock will not be important among consumers focused on the end result.
“The feedstock will not be a concern. The quality will be the same from both sources,” Todd said. “By the time the manganese has been crystalized it does not matter.”
The process of making metal as an intermediate product can help purification.
“However, proponents of the first method like the elimination of the electrowinning stage to reduce power costs,” Fraser said. “However, this often comes at the expense of purity and any savings on power costs can quickly be outweighed by additional costs of the reagents needed to achieve the desired purity levels.”
Producing metal as an intermediate product provides the opportunity for further versatility for end use products as battery chemistries and consumer requirements evolve, according to Fraser.
This is particularly valuable given evolving approaches to battery chemistries.
“While there is an assumption at present that the desired form of manganese is sulphate, there are others who are looking at different forms of manganese – such as metal, oxide, carbonate or even nitrate. Working from metal gives us the option to adapt our process to deliver these products,“ he said.
Although manganese metal can be used in the production of sulfate, there are significant concerns around the potential risks of selenium and its impacts on sulfate.
Selenium is often used in the production of manganese metal in order to reduce power consumption and operating costs, though this method is highly concentrated in China, where the majority of global manganese metal is currently produced.
Manganese sulfate products containing selenium are often not desired within Western markets, sources said.
“Selenium is very toxic and gives off a garlic distinctive aroma in the lab during dissolution,” Todd said, adding “If you start with 99.7% chemistry manganese flake then you need to remove the selenium.”
However, it is difficult process to remove the selenium, but it carries a risk if it is not removed.
“If it ended up in manganese sulphate destined for EV batteries, even very small quantities could cause significant safety-related and other technical problems, such as short-circuits,” Fraser said.
Euro Manganese is looking to produce selenium-free metal at its Chvaletice project in Czechia.
There are reports that some consumers of manganese sulfate are happy to take material containing selenium for small-scale batteries, but this is not widespread.
Any manganese products containing selenium require an additional processing stage to remove the selenium, which can then be stored in an approved hazardous waste facility, adding to costs.
Historically, manganese flake has been the dominant method of production of manganese sulfate, but issues around selenium have seen participants switch to the use of metal or ore as a feedstock.
“Flake was dominant – it was dissolved and crystallized, but it was not always purified properly. But now ore is currently the dominant route to sulfate production as it is less expensive,” Todd said.
Manganese flake prices are largely unimpacted by such developments, given that steel consumption continues to make up the vast majority of overall demand for the material.
Instead, volatility in manganese metal prices have typically been related to supply factors.
In the second half of 2021, manganese flake prices increased markedly, to reach an all-time high.
Fastmarkets’ price assessment for manganese 99.7% electrolytic manganese flake, fob China reached $7,000-7,150 per tonne on October 29, 2021. The price was up by 187.3% from $2,450-2,520 per tonne on May 7, 2021.
This price increase was credited to supply concerns and production cuts among major production hubs to help meet environmental targets.
On the other hand, manganese sulfate prices have historically been heavily impacted by fluctuations in manganese flake prices.
In 2022, as manganese flake prices softened, manganese sulfate prices moved largely in parallel.
On March 17, 2022, in the first pricing session of Fastmarkets’ manganese sulfate 32% Mn min, battery grade, exw mainland China price assessment, prices were assessed at 9,000-10,000 yuan per kg. One year later, on March 16, 2022, this price had fallen to 5,800-6,300 yuan per kg, marking a decline of 36.32%.
Between March 18, 2022 and March 17, 2023, the price for manganese 99.7% electrolytic manganese flake, fob China fell from $3,500-4,000 per tonne to $2,150-2,200 per tonne – a 42% decline.
This article is part three of three in our spotlight on sulfate series, focused on manganese sulfate. Read the other articles here.