Not half an hour, not ten minutes, not even one minute.
Recently, scientists have developed a brand-new battery that can be fully charged in a matter of seconds, faster than filling up with gasoline. With a swift swoosh, it's fully charged.
Once this new battery is mass-produced and implemented, it means the era of range anxiety will be a thing of the past.
This latest research achievement has been published in the prestigious academic journal "Energy Storage Materials," led by Professor Jeung Ku Kang from the Department of Materials Science and Engineering at the Korea Advanced Institute of Science and Technology (KAIST).
The new battery isn't your typical lithium-ion polymer; it's a sodium-ion battery, which high-performance electric cars aren't too keen on.
A slew of new batteries are hitting the scene, but most are tinkering with the materials of the battery's positive and negative electrodes.
The team at the Korea Advanced Institute of Science and Technology (KAIST) is no exception, integrating conventional battery anode materials with a novel cathode suitable for supercapacitors into this sodium-ion battery.
However, sodium-ion batteries typically come with their drawbacks, such as lower power output, shorter cycling life, limited storage performance, and longer charging times.
The sodium-ion battery jointly developed by the Department of Materials Science and Engineering at the Korea Advanced Institute of Science and Technology (KAIST) has addressed many previous shortcomings. It not only achieves high-capacity storage but also enables rapid charging and discharging, reaching full charge in just a few seconds.
According to Jeung Ku Kang, this sodium-ion battery boasts the highest energy density to date, at 247 Wh/kg. Compared to commercially available lithium-ion batteries, such density data is remarkably impressive.
Its rapid charging power density reaches up to 34,748 W/kg, surpassing battery reactions by over 100 times. Moreover, even after 5000 charge-discharge cycles, it maintains 100% Coulombic efficiency, exhibiting exceptional cycling stability.
It's evident that this sodium-ion battery achieves both high energy density and high power density simultaneously.
The reason behind this remarkable performance lies in addressing the slow charging of battery anode materials and the relatively low capacity of supercapacitor cathode materials.
Jeung Ku Kang's team utilized two different metal-organic frameworks on the cathode and anode, respectively, and optimized the synthesis to develop a hybrid-type battery.
The negative electrode material is synthesized from a heterostructure of iron-based metal-organic frameworks (MOFs) and graphene oxide via graphitization and sulfurization, forming iron sulfide doped carbon/graphene (FS/C/G). This material is then embedded into porous carbon derived from metal-organic frameworks.
Experimental findings reveal that cyclic ultrafine iron sulfide is chemically redefined during reactions as low-crystallinity conductive fragments with Fe vacancies and multivalent Fe/Fe states. These minute conductive fragments enable high-capacity/high-rate performance.
They also synthesized high-capacity cathode materials using zeolitic imidazolate framework (ZIF) as a precursor, forming three-dimensional porous doped oxygen-carbon cathode materials through pyrolysis-assisted micropores and KOH-assisted mesopores formation. The surface area of this ZIF-derived porous carbon (ZDPC) reached 3972 m/g, about 20 times higher than that of traditional ZDC.
The larger surface area increases the efficiency of sodium ions passing through, thereby enhancing the energy rate.
The combination of such cathode and anode materials balances and reduces the differences in energy storage rates, thus creating a high-performance sodium ion storage system. Moreover, this new high-capacity cathode material balances and reduces the differences in energy storage rates.
This is also the key to the rapid charge and discharge of this battery.
02
Bumpy Roads, Bright Future
In 2022, the concept of sodium-ion batteries started gaining traction. Leading battery manufacturers like CATL successively introduced sodium-ion batteries and expressed their commitment to the industrialization of the sodium battery supply chain.
Similar to lithium-ion batteries, sodium-ion batteries are also rechargeable secondary batteries. Their working principles are quite similar, with the main difference lying in the charge carriers and the cathode materials. In sodium-ion batteries, the electrode material is sodium salt, while in lithium-ion batteries, it's lithium salt.
Sodium-ion battery cathode materials currently consist of three main types: Prussian blue, layered oxide, and poly-anionic cathode. Lithium-ion cathode materials mainly include lithium manganese oxide, lithium iron phosphate, lithium cobalt oxide, lithium nickel oxide, and lithium nickel cobalt manganese oxide.
Sodium-ion batteries use sodium salt as the electrode material, which has a richer reserve and lower cost compared to lithium salt. Additionally, sodium-ion batteries adopt iron-manganese-nickel-based cathode materials, which can reduce raw material costs by half compared to ternary cathode materials used in lithium-ion batteries. Sodium ions do not form alloys with aluminum, allowing aluminum foil to be used as a current collector for the negative electrode, reducing weight by around 10% and costs by around 8%.
In addition to lower costs, sodium-ion batteries also offer advantages such as more stable performance, less susceptibility to self-discharge, and reduced risk of thermal runaway. Especially in low-temperature environments, sodium-ion batteries exhibit even higher battery capacity retention rates than lithium iron phosphate batteries under equivalent conditions. They can operate normally in temperature ranges from -40°C to 80°C, with capacity retention rates close to 90% even at -20°C, thus alleviating range anxiety.
Source: Internet
In terms of safety, sodium-ion batteries have demonstrated high stability in tests such as overcharging, over-discharging, short circuits, punctures, and compression. They can also be transported at 0V, significantly reducing the risk of spontaneous combustion during transportation.
The recharging efficiency is also high. At room temperature, sodium-ion batteries can replenish 80% of their charge in just 15 minutes.
While the advantages are evident, so are the drawbacks. For instance, the cycle life of sodium-ion batteries is currently only 2000-3000 cycles, compared to the 6000 cycles achieved by lithium iron phosphate batteries. There's still a significant gap between the two.
Low energy density is also a major technical challenge for sodium-ion batteries at this stage. According to available data, the energy density of the first-generation sodium-ion batteries from CATL has reached 160Wh/kg, while ternary lithium batteries in the lithium-ion camp have reached 300Wh/kg.
In summary, when weight and energy density requirements are not high, sodium-ion batteries can be seen as a "drop-in" replacement for lithium batteries. Therefore, in the field of new energy vehicles, sodium-ion batteries are generally used in micro and compact cars.
Known brands that use sodium-ion batteries include Chery New Energy, Jiangling New Energy, and JAC's new energy vehicle brand, JAC Yiwei.
As early as April 2023, CATL announced that its sodium-ion batteries would debut in Chery vehicles. At the same time, Chery will collaborate with CATL to launch the battery brand "ENER-Q".
On December 28, 2023, Jiangling Group New Energy launched its sodium-ion battery-powered vehicles equipped with Farasis Energy Technology's sodium-ion batteries. The Jiangling Yizhi EV3 (Youth Edition) 251km version became the world's first sodium-ion vehicle to be delivered. Currently, the energy density of sodium-ion batteries in production ranges from 140 to 160Wh/kg.
On January 5, 2024, Jianghuai Yayi officially delivered the world's first mass-produced sodium battery-powered vehicle, the Hua Xianzi, to customers. It features a honeycomb battery safety structure, with a total battery pack capacity of 23.2 kWh. The CLTC (China's Local Test Cycle) range reaches 230 km, with an energy consumption of nearly 10 kWh per 100 km.
It is reported that the sodium-ion version of the Flower Fairy, equipped with 32140 sodium ion cylindrical cells supplied by Zhongke Hai Na, has a single-cell capacity of 12Ah and an energy density of ≥140Wh/kg. It adopts the technical route of copper-based layered oxide + hard carbon, possessing advantages such as high safety, high energy density, good low-temperature performance, and long cycle life.
Addressing the drawbacks of sodium-ion batteries, in February 2024, the team led by Xie Hongwei from Northeastern University published an article in the internationally renowned journal ACS Energy Letters, demonstrating the synthesis of nano-graphite sheets as sodium storage negative electrode materials. This provides a new design concept for the development of high-rate, long-cycle sodium-ion battery negative electrodes, creating opportunities for the practical application of sodium-ion batteries in large-scale energy storage, and further promoting the industrial layout of sodium-ion batteries.
Who will dominate the future of batteries?
As the cost of lithium-ion batteries continues to rise year by year, their performance at low temperatures is increasingly unable to meet industry demands.
Against the backdrop of "the world suffering from lithium," the industry is beginning to search for better battery solutions. Gradually, sodium-ion batteries and solid-state lithium-ion batteries have emerged as two highly regarded candidates.
In particular, over the past two years, industry manufacturers and automakers have been racing to deploy solid-state lithium batteries, with frequent news of industrialization landing. Many models have already hit the road ahead of schedule, suggesting that 2024 could indeed mark the beginning of the era of solid-state batteries.
For example, Zhiji L6 became the first to be equipped with the industry's first mass-produced 900V ultra-fast charging solid-state battery. Towards the end of last year, NIO installed a 150kWh semi-solid-state battery in the ET7, achieving a real-world range of over 1000 kilometers. Not long ago, NIO also announced that the 150kWh ultra-long-range battery pack has officially entered mass production and is planned to be put into use in the second quarter.
While both of the aforementioned solid-state batteries were soon debunked and proven to be not purely solid-state batteries, but rather a hybrid between solid-state and liquid lithium batteries, the fact remains that solid-state batteries are on the brink of mass production.
However, the development of sodium batteries is not a recent phenomenon but dates back more than 30 years ago when lithium batteries were first introduced. Yet, despite this early emergence, sodium batteries have not gained widespread market acceptance.
The primary reason for this is their significantly lower energy density compared to lithium batteries, which makes them unable to meet the demands of practical applications. Although the recent surge in lithium salt prices has spurred the development of sodium batteries, their energy density remains one of their fatal weaknesses.
Moreover, the manufacturing cost of sodium batteries is currently still high, and the production process is relatively complex, which also limits their competitiveness in the market.
Nevertheless, if the new generation of sodium-ion batteries can be mass-produced, they will propel electric vehicles into a whole new stage, capable of being fully charged in a matter of seconds. Who needs bicycles anymore?
