KAWANISHI-CITY, Japan, Aug. 22, 2023 /PRNewswire/ — Climate change, global warming (boiling) problem is becoming a serious issue and immediate action is necessary in order to mitigate the rising temperature. The propagation of modern human society is emitting huge quantity of CO2 gas every second and the renewable energy is more ideal because they do not consume fossil fuel to release CO2. But shortcomings of renewable energy such as solar or wind power is that they cannot produce electricity when the sun is down or wind isn’t blowing. In this respect, rechargeable battery is very important since it can help store surplus energy. Even at night or when wind isn’t blowing, rechargeable batteries can discharge that stored surplus energy to continue supporting power needs. This is the most necessary issue to build up renewable energy based society.
Nowadays, the lithium ion battery is the predominant commercial rechargeable battery widely used in portable electronics and electrified transportation such as EVs. Therefore, it is the best to install more numbers of lithium ion battery to the society. However, the lithium ion battery suffers from its high price which mainly originates from rare metal cost including cobalt, nickel, manganese and lithium for their cathode (positive electrode). In addition, for example as cobalt, about a half of global cobalt ore supply originates from the politically unstable country such as Democratic Republic of the Congo (DRC) and its supply is vulnerable. Furthermore, child labor exploitation and political corruption for cobalt production also have been concerned issues. It is also said that cobalt mining is causing water pollution, contaminating crops and soils.
Therefore, lithium ion battery recycling would be the good choice instead of mining metals from earth ground. For lithium ion battery recycling, once a battery is retired and collected, they are shredded and base metals and other impurities are separated to prepare them for recycling. Then after, shiny, metallic mixture called “black mass” is obtained. And this black mass contains all the valuable metals that make up battery electrode including cobalt (the most expensive parts of a battery).
Black mass makes up about 40-50% of the total weight of an EV battery. Materials like the graphite, binder, electrolytes, plastics, aluminum, copper, iron and steel have been physically separated out by shredders before being recycled.
Then from this black mass, expensive rare metals can be extracted and re-used for new batteries (cathode) or new electronic products. Recently, this kind of black mass research has been active in universities and private companies.
Metal extraction from black mass have been performed with strong toxic chemical such as sulfuric acid, hydrochloric acid, sodium hydroxide, etc; however, these chemicals are toxic and cause damage to the surrounding environment including machineries, factories and dangerous to human operators.
In this regard, Dr. Ryohei Mori has developed new cathode preparation process which can directly made from black mass. With this procedure, the cost will be much cheaper because those metal extraction process with toxic chemicals can be eliminated. This is such advantage in terms of cost and process. In addition, black mass itself is cheaper than general cathode materials such as LiCoO2, NMC 111, etc.
The prepared lithium ion battery assembled with cathode directly made from black mass, delivered an initial discharge capacity of approximately 85 % compared to those of commercial NMC111 cathode, together with high cycle stability. As a result, by eliminating the metal extraction process with toxic chemicals and because black mass price itself is cheap, cathode cost can be cheaper than a half of price of commercial based cathode.
Green Science Alliance will keep improving cell capacity, cycle stability as well as start sending out samples to cooperation company and investors.
SOURCE Green Science Alliance Co., Ltd.