Prospects of battery materials : rebirth of sodium electricity, hard carbon first
- Speed up the industrialization of sodium power
- Lithium and sodium performance comparison
- Hard carbon is expected to break down technical barriers
- The hard carbon market is growing rapidly
Sodium electricity is expected to break the constraints of lithium resources, and hard carbon is expected to take the lead in industrialization. At present, with the prominent supply bottleneck of lithium resources and the enrichment of secondary battery application scenarios, sodium power has regained market attention.
Sodium battery has the advantages of low cost and high safety, and may be a powerful supplement to lead-acid batteries and lithium iron phosphate batteries.
Compared with the lithium iron phosphate battery materials system, the performance bottleneck of the sodium battery at the negative end is more prominent, and the hard carbon has a rich sodium storage environment, and the theoretical sodium storage gram capacity reaches 530mAh/g.
Combined with its advantages such as low price, small volume deformation after sodium intercalation, low temperature and good fast charging performance, it is more likely to become the first commercial sodium anode battery materials.
The hard carbon market has grown from scratch, and the market is growing rapidly. The industrialization of hard carbon in China is not yet mature. However, considering the good application prospects of hard carbon in the field of sodium battery and lithium battery anode doping.
It is expected that the demand for hard carbon battery materials is expected to increase from 20,000 tons/year to 105,000 tons/year in 2022~2025. Considering the fall in carbon prices, it is expected that By 2025, the market space for carbon battery materials is expected to reach 6.3 billion RMB.
Speed up the industrialization of sodium power
The demand side of lithium resources continues to be strong, and the cost of lithium battery materials continues to rise. With the rapid development of portable electronic devices and new energy vehicles, the production scale of lithium-ion batteries is increasing. According to estimates, world lithium demand is expected to increase from 769,000 tons of LCE to 1.633 million tons of LCE in 2022-25.
The demand side of lithium resources continues to be strong, but the reserves of lithium in the earth’s crust only account for about 0.0065%. And its distribution is mostly located in remote areas, which increases the cost of lithium resource mining, extraction, transportation, processing and other links.
As of January 2022, the world’s total proven lithium resources are about 89 million tons, and the developable reserves are about 22 million tons. Since 2021, with the rapid increase in the penetration rate of electric vehicles, the price of lithium has continued to rise. At present, the price of one ton of lithium carbonate has reached 494,000 RMB. Only considering the cost of the positive electrode, the difference between the two is 150 times. In this way, here is a top 5 lithium carbonate factories in China for you to read.
Lithium and sodium performance comparison
The working mechanism of sodium battery materials is similar to that of lithium battery materials. Sodium and lithium belong to the same main group element, and their chemical properties and battery materials working principles are very similar. Both sodium and lithium batteries belong to rocking chair batteries.
Their positive and negative electrodes are battery materials with sodium storage ability, and the sodium ions shuttle and deintercalate between the positive and negative electrodes to achieve the purpose of energy storage and release.
The fundamental difference between the two types of battery materials systems is the difference in conductive ions (Li+ vs. Na+), and the differences in the ionic radius, solvation ability, and electrochemical potential of the two ions ultimately lead to different battery materials systems.
Compared with lead-acid batteries, sodium-ion batteries have obvious advantages in energy density and safety, and compared with lithium iron phosphate batteries, they have advantages in cost, safety and low-temperature performance. The large reserves of sodium element are distributed all over the world, making the price of the main battery material of sodium battery materials much lower than that of lithium battery materials.
At the same time, the sodium-ion battery is easy to be passivated and deactivated during the thermal runaway process, and will not catch fire and explode in safety tests such as overcharge, overdischarge, extrusion, and acupuncture. Sodium batteries have certain advantages in terms of safety performance.
It is expected that sodium-ion batteries may replace lead-acid batteries in the field of low-speed electric vehicles. In the field of energy storage, sodium-ion batteries may be a powerful supplement to lithium iron phosphate batteries.
Hard carbon is expected to break down technical barriers
Hard carbon is expected to be the first to achieve commercial application in sodium-electric anode battery materials. It has the following advantages:
1. Hard carbon has excellent sodium storage performance. They have various types of reversible sodium storage sites. Ideally, it can provide a theoretical capacity of about 530mAh/g.
2. Hard carbon is non-graphitizable carbon, which refers to carbon battery materials that cannot be graphitized above 2800°C.
3. Compared with the long-range ordered layered structure of graphite, the arrangement of carbon crystallites in hard carbon shows the characteristics of random orientation, which is more disordered and disordered than that of soft carbon.
4. From the perspective of microstructure, hard carbon has a rich sodium storage environment, and the sodium storage sites include graphite interlayers, closed micropores, surfaces and defect sites.
5. It is estimated that the theoretical capacity of sodium storage contributed by interlaminar deintercalation and closed-cell filling is 279 mAh/g and 248 mAh/g, respectively, for a total theoretical capacity of about 530 mAh/g.
Hard carbon is more likely to become the first commercial sodium electrode material. At present, the research of anode battery materials for Na-ion batteries mainly focuses on carbon-based battery materials, alloys, transition metal oxides and organic compounds.
Among many anode battery materials, hard carbon battery materials have the advantages of diverse structures, low price, good electrical conductivity, high sodium storage capacity, small volume deformation after sodium intercalation, environmental friendliness, and low redox potential.
The soft carbon layer spacing is smaller than that of hard carbon, and the specific capacity of soft carbon for sodium storage is only 220mAh/g. Its volume capacity is difficult to increase, and its low temperature performance and fast charging performance are not as good as hard carbon.
Alloy battery materials have the problems of severe volume expansion and poor cycle stability during sodium storage. Metal compound battery materials have poor electrical conductivity and large volume changes during cycling, resulting in poor rate performance and cycle stability. Organic compounds are easily dissolved by organic electrolytes.
Hard carbon anodes suffer from low initial efficiency and poor cycle stability in sodium-ion batteries, which need to be improved. Bottleneck problems such as low first Coulomb efficiency can be improved by means of structural design, heteroatom doping, surface functionalization, and pre-sodiumization.
The main methods for improving the electrochemical performance of hard carbon-based anodes are: improving the structure of hard carbon-based battery materials and optimizing the composition of the electrolyte. You can read our article of top 10 lithium battery anode material factories in China to know about the industry trend.
The hard carbon market is growing rapidly
The energy storage scene provides solid support for the application of sodium electricity, and the power battery enriches the application scene of sodium electricity. Energy storage provides a solid application scenario support for the application of sodium electricity.
Considering the current situation of the slow industrialization of sodium electricity, in the field of electrochemical energy storage, it is estimated that the proportion of new sodium electricity will account for about 15% in 2025.
In the field of power batteries, sodium-ion batteries mainly replace lead-acid batteries and lithium iron phosphate markets. The main application scenarios are in low-speed passenger vehicles and commercial vehicles. At present, due to the immature industrialization of sodium electricity and the high cost, it is estimated that the penetration rate of related power battery application scenarios will not exceed 2% before 2024.
The carbon market has grown from nothing, and the demand is expected to increase from 2,000 tons to 105,000 tons in 2022-2025. Hard carbon is mainly used as negative electrode battery material for sodium-ion batteries and lithium-ion power batteries partially doped with carbon.
Experts estimate that the demand for carbon battery materials from 2022 to 2025 is expected to increase from 2,000 tons/year to 105,000 tons/year.
The main application background of hard carbon is the anode of sodium ion battery materials. If the penetration rate of sodium-ion batteries is lower than expected, it will affect the downstream demand of hard carbon, and the company’s motivation to deploy carbon production capacity may weaken.