SK Innovation aims to be a leader in battery recycling

Keeping pace with the rapid growth of the electric vehicle (EV) market, the EV battery market is also growing fast. Global demand for EV batteries will reach 2,740 GWh in 2030. Given that the average lifespan of the battery is six to 10 years, it is expected that there will be a dramatic increase in the disposal of used batteries.

In fact, the global market for battery recycling is projected to grow more than 113 times, from 1.2 GWh this year to 136 GWh in 2030, according to market research firm Guide House Insights. SNE Research also forecasts the used battery market will grow to USD18.1 billion by 2030.

South Korea’s SK Innovation has applied for 54 patents in the area of battery reuse. Under the motto of “mining batteries from batteries,” the company has developed its own technology to collect lithium hydroxide based on its experience from operating oil refineries.

Valuable minerals that are found from lithium-ion batteries include lithium, nickel, cobalt, and manganese. In 2019, SK Innovation developed a technology for lithium collection in the form of lithium hydroxide (LiOH), which can be directly applied to cathodic material production of high-Ni batteries like NCM811 (batteries with 8:1:1 ratio of nickel-cobalt-manganese).

In terms of used battery recycling technology, extracting the key materials, such as lithium, nickel, and cobalt from cathodes has already been commercialized, but the technology for collecting lithium in the form of high-purity lithium hydroxide is not there yet. It is acknowledged that the lithium hydroxide collection technology SK Innovation has developed has an advantage of extracting key materials, such as nickel and cobalt in higher volumes and purity.

Moreover, utilization of lithium hydroxide, nickel, cobalt, and manganese extracted from used batteries also gives a competitive edge to secure carbon credit. SK Innovation’s extraction technology of lithium hydroxide can reduce carbon emissions from 40& to 70% of the emission from mining lithium at mines or saline lakes and processing it. Recently, several European vehicle manufacturers have asked their subcontractors to report the carbon emissions during the processes to produce the parts. In this context, the reduction of carbon emissions through SK Innovation’s technology is considered meaningful in the industry.

Therefore, with this cutting edge technology to drive its effort for battery recycling, SK Innovation is planning to expand the use of the batteries into energy storage systems, flying cars, robots, etc., not just electric vehicles. Also, the company is going to develop and foster new projects, for example, the Battery as a Service (BaaS) platform project to manage batteries more effectively throughout the product life cycle.

EV batteries consist of cells, modules, and packs. The minimum unit for a battery is a cell, made of various materials. A module is a certain amount of cells packed into the frame which protects the contents from outside impact, heat, etc. This module is combined with the system for control and protection, such as the battery management system (BMS) and the cooling system. This combined body is a pack.

Reuse literally means to use the batteries again. Here, degraded or wasted batteries are used with reassigned purposes. First, they are examined for residual energy and charge/discharge and for those recollected due to relatively better performance, we can reassemble them as modules and packs to reuse.

Energy Storage System (ESS) is a good example of battery reuse. Batteries used for ESS can retain availability until capacity decreases to 50%. The U.S. National Renewable Energy Laboratory, in their analysis, found that a wasted battery can be reused as ESS for another decade, even though its capacity has dropped to 70% of a new one. These used batteries are can also be reused for other purposes such as for emergency power device or other electronic mobility equipment.

Generally, batteries that are not ideal for reuse and already reused batteries are recycled. Recycling batteries means extracting valuable metallic resources, such as nickel, cobalt, etc. from collected batteries through physical and chemical disintegration. Battery recycling can reduce carbon emission from EVs by as much as 7%.

Extracting valuable metallic resources requires pre-processing. Discharged waste batteries are deactivated and physically dismantled to collect parts made of aluminum. Then, a mixture of ‘black powder’ containing lithium, nickel, cobalt and manganese is produced from mechanical grinding and crushing.

What remains from the pre-process needs to pass through one of three processes: the dry process, the wet process, and the direct recycling. During the dry process, the remains are processed with smelting reduction under very high temperatures. Nickel, cobalt, copper, etc. are extracted during the process. During the wet process, black powder, the product from pre-processing, is dissolved in acid to collect resources as refined chemical compounds or metals. And the last process, direct recycling, makes cathodic material into regenerated form for use in new products, though it is not yet utilized for mass-production.