The World is in a Battery Resource War... Korea Survives with 'This Technology' [Reading Science]

Development of Organic Secondary Batteries Instead of Rare and Toxic Transition Metals like Cobalt
Lightweight and Eco-friendly, Advantages Include Solving Raw Material Supply Issues
Technical Challenges to Overcome Include Organic Material Dissolution, Self-discharge, and Short Lifespan

Next-generation battery. Stock photo. Not related to the article.

[Asia Economy Reporter Kim Bong-su] The world is currently in the midst of a resource war era. Especially with the rapid spread of electric vehicles and energy storage systems (ESS), the usage of batteries has surged significantly, causing the prices of essential resources such as lithium, nickel, and cobalt to skyrocket to the point of becoming subjects of international conflict. These rare and heavy metals are facing clear structural limitations in terms of capacity, safety, and efficiency. They are heavy, highly toxic, have low utility, and pose significant challenges in waste disposal. Consequently, active research is underway in South Korea to develop eco-friendly secondary batteries using organic materials instead of rare and heavy metals.

◇ The World is Now in a Battery Resource War

Recently, global battery demand has surged rapidly, causing raw material prices to soar sharply. Lithium prices have increased more than fivefold compared to a year ago, nickel has reached its highest price in a decade, and cobalt prices have nearly doubled. The United States and China, engaged in a global hegemony competition, are already at 'war' over battery materials. China has recently acquired battery raw material mining companies and mines to dominate the market, while the U.S. is securing its own supply sources centered in California and Nevada. South Korean companies, lacking their own supply chains, are expanding contracts with Australia and China but are facing difficulties due to logistics and production disruptions.

Additionally, the toxicity of key battery materials like cobalt is a concern. Cobalt is a rare metal with about half of the world's reserves located only in the Democratic Republic of Congo, Africa. While it is a component of vitamin B12, it is known to be highly toxic. The name cobalt derives from the German word "kobalt," meaning ghost or demon. In the 16th century, German miners were terrified when toxic gases emitted from cobalt-containing ores caused deaths. Excessive inhalation of cobalt can cause fatigue, diarrhea, palpitations, and numbness or tingling in the hands and feet.

The recent spotlight on the recycling industry of spent batteries is due to the soaring prices, rarity, and environmental pollution issues associated with traditional battery materials like cobalt. Moreover, energy storage materials made from transition metal oxides can only be used as electrodes if they have an open framework structure that allows lithium ions to move in and out. Due to the 'insertion-deinsertion mechanism,' the structure becomes unstable when lithium ions leave, limiting the usable theoretical capacity. Transition metals like cobalt also have the disadvantage of being heavy and emit significant greenhouse gases during production and disposal. The electric vehicle and ESS markets are rapidly expanding and are expected to exceed 3 TWh by 2030.

◇ Organic Batteries as an ‘Alternative’

Accordingly, worldwide efforts are underway to develop batteries using organic materials to overcome the drawbacks of lithium secondary batteries made from transition metals like cobalt and to combat global warming. Using organic materials for electrodes and electrolytes can first solve raw material supply issues. Additionally, the manufacturing and disposal processes are eco-friendly, and the battery weight is drastically reduced. Advantages also include fast charging, excellent variability, and high energy density. Professor Jeon Seok-woo of KAIST’s Department of Materials Science and Engineering explained, "Research is actively progressing to create battery electrodes using organic materials capable of redox reactions, similar to hemoglobin in the human body. Because they are inexpensive and lightweight, they can maximize the efficiency of batteries used in electric vehicles and ESS."

The challenge lies in lifespan and stability. Organic secondary batteries, which require hundreds of charge cycles, have the clear drawback of rapid capacity degradation and short lifespan due to the easy dissolution of components. Recently, technologies that significantly improve the safety and durability of materials have been developed, achieving performance comparable to or slightly better than conventional transition metal-based batteries, but they have yet to attract the interest of established companies. Professor Jeon said, "(Battery manufacturers with significant facility investments) will likely require performance improvements of two to three times before showing interest in commercialization. Just as the existing lithium transition metal battery technology was not expected to become so widespread and commercialized when first invented, organic material battery technology will also require long-term investment and a research platform to achieve good results."

Battery. Stock photo.

◇ South Korea ‘At the Forefront’... Many Unresolved Challenges

South Korea is a powerhouse in conventional lithium transition metal batteries. Accordingly, next-generation battery research is active, and the country is leading the development of organic semiconductors for next-generation lithium batteries that are cost-effective and environmentally friendly enough to prevent conflicts. The research team led by Professor Kim Jae-kwang at Cheongju University was the first to develop technology in April 2016 that uses carbon nanotubes to address issues such as high self-discharge and battery short circuits in organic secondary batteries. At the time, this technology was praised for providing a key idea for developing next-generation secondary batteries that could solve existing battery problems.

More recently, in November last year, Professor Jeon’s team developed core technology for next-generation eco-friendly organic secondary batteries. Using optical patterning technology, they designed a highly aligned nanonetwork-structured organic anode that dramatically improved the performance of lithium-organic batteries. Instead of a disordered electrode structure, they introduced a three-dimensional dual-continuous structure organic polymer-nickel composite electrode with aligned submicron (less than one-millionth of a meter) sized pore channels. It was confirmed to have high durability and stability, maintaining over 83% of electrode capacity during 250 charge-discharge cycles at a high current density of 15 A g-1. They also achieved a high reversible capacity of 1,260 mAh g-1. The research team led by Lee Jin-woo in the Department of Bio and Chemical Engineering at the same university developed technology in September last year to create porous two-dimensional inorganic nanocoins that effectively suppress the dissolution of lithium polysulfides, a cause of performance degradation in lithium-sulfur batteries, thereby enhancing performance. Additionally, the research team of Professors Byun Hye-ryeong and Kim Woo-yeon at the same university succeeded in May last year in developing a lightweight, flexible, and high-performance lithium-organic hybrid battery. They designed a large porous structure by linking molecules with a benzosiazole linker, where two nitrogen atoms form an azo (N=N) group as a redox core. The organic monomers form a two-dimensional film through covalent bonds, which then grow into a three-dimensional porous crystal via pi-pi interactions. This skeletal structure enhances intermolecular interactions and stability within the battery and improves chemical stability, insolubility, and electrical ion conductivity.

The lithium-organic battery technology developed by the Korea Institute of Science and Technology (KIST) research team in 2019 is also gaining attention. This idea replaces graphite, commonly used as the anode material in lithium secondary batteries, with a combination of organic semiconductors such as fullerene and a glove-shaped material called hexabenzocoronene as the anode. While graphite has drawbacks that reduce battery performance, charge-discharge speed, and lifespan, the material devised by the research team exhibits excellent electrical conductivity without mixing other materials, making it promising for next-generation lithium-organic battery materials.

However, recent findings indicate that the performance degradation of organic secondary batteries is not due to the dissolution of the organic electrode itself but rather the shuttle effect, where dissolved electrode materials migrate to the opposite electrode. This has emerged as a key research challenge. Professor Kang Ki-seok of Seoul National University pointed out in a recent report prepared by the National Research Foundation of Korea, "Many domestic research teams are developing new concept next-generation secondary battery systems that are gaining global academic attention. It is necessary to develop organic electrode materials that do not dissolve easily. By utilizing promising materials in polymer form or forming structures that do not dissolve easily, it is essential to reduce the solubility in organic solvents and develop organic secondary batteries with long lifespans."

Professor Kang added, "Currently, electrode manufacturing processes borrow from those used for oxide-based electrode materials. It is necessary to develop suitable electrode manufacturing processes that can mitigate the solubility of organic secondary batteries and secure electrical conductivity. The migration of dissolved organic materials from the electrolyte to the opposite electrode can also be controlled through separator engineering. Research is needed to establish long-life organic secondary battery systems through innovative separator process development."