Lithium ion battery is mainly composed of electrolyte, separator, cathode material and anode material. As one of the four key materials for lithium battery manufacturing, electrolyte is the medium for lithium ion migration and charge transfer, known as the "blood" of lithium batteries.
As an important component of lithium batteries, electrolyte additive have a direct and significant impact on the performance of lithium batteries, so increasing the functional role of electrolyte additive in lithium batteries is an important way to improve the performance of lithium batteries.
1. Electrolyte additive VC
The additive has the characteristics of small dosage and significant effect, which can significantly improve the performance of lithium batteries without increasing production costs and changing production processes.
In high energy density lifepo4 batteries, electrolyte additive as auxiliary materials, added in small quantities previously accounted for less than 8% of the electrolyte additive cost structure. The average market price of VC electrolyte additive declined.
The sharp increase in VC prices at the end of 2021 was due to the imbalance between supply and demand, and the sudden increase in customer demand. With the increase in capacity utilization of VC producers, the supply side has increased, and VC producers may have stocked up before, but now they are shipped, so the price has decreased.
2. Electrolyte additive DTD
● Brief description of DTD (vinyl sulfate)
DTD (vinyl sulfate) is a film forming additive of SEI. The proportion of lithium iron added is less than 1%, and the proportion of ternary added is less than 3%. At present, the preparation of DTD is mainly based on thionyl chloride and ethylene glycol as raw materials.
● Market size
Ternary batteries have higher energy density, but the disadvantage is poor thermal stability, and DTD can improve the battery's high-temperature cycle, high-temperature storage performance, and reduce battery expansion after high-temperature placement.
So the study report believes that a higher proportion of DTD needs to be added to the ternary battery. DTD is a relatively new additive, mainly added to ternary lithium, but the proportion of lithium iron phosphate has exceeded ternary. Consequently, the compound annual growth rate of DTD is still conservatively estimated at 20%.
● DTD market price
Since 2018, the market supply of vinyl sulfate has increased, so the price of vinyl sulfate has decreased accordingly, and the current unit price is about 230,000 RMB per ton.
The study predicts unit prices will fall by 10% annually. Vinyl sulfate prices continued to decline from 2019 to 2021, mainly due to:
The vinyl sulfate production process is improved and the cost is reduced.
The top 5 battery electrolyte companies continue to lay out upstream raw materials, driving down the price of vinyl sulfate.
Vinyl sulfate prices rebounded from January to March 2022, mainly due to the booming downstream EV industry and the tight supply and demand of upstream raw materials, and the price increased.
3. Electrolyte additive industry scale
① Industry development status
The development of global electrolyte additive is deeply affected by the development of the lithium battery industry. Major lithium battery producing countries have been affected to varying degrees, resulting in a slowdown in the growth rate of lithium battery production, which in turn affects the market demand for electrolyte additive.
Power batteries are the largest downstream application field of electrolyte additive. Benefiting from the development of the EV industry, China's rising demand for power batteries has driven the development of lithium battery electrolyte.
The scale of China's lithium battery electrolyte market has increased. The market size of electrolytes is related to the output of lithium batteries in a certain proportion, and the increasing demand for lithium batteries promotes the rising market size of electrolyte additive.
With the continuous expansion of the scale of lithium battery industry and EV and the improvement of battery safety, cycle life and energy density requirements, more requirements are put forward for electrolyte additive, and the demand for additive in film formation, conductivity, flame retardant, overcharge protection, and improving low temperature performance will gradually increase.
② Supply side
The global output of electrolyte additive has steadily increased, and Chinese companies are the absolute main force in the additive industry. In the future, the new additive production capacity will largely depend on the expansion of Chinese enterprises. Among battery companies, Guangzhou Tycorun Energy is a professional lithium battery seller.
4. Electrolyte additive substitute for risk factors
① Hydrogen cell
Hydrogen fuel cells are batteries that use the element hydrogen to store energy, and the basic principle is the reverse reaction of electrolysis of water. Compared to lithium batteries, hydrogen fuel cells have the following advantages: Low energy conversion consumption.
The speed of hydrogenation is faster than the speed of charging, which is more in line with the needs of long-term and efficient transportation. No pollution to the environment, basically achieving zero carbon emissions.
However, hydrogen fuel cells are still in the early stages of industrialization, and there are still many problems to be solved:
- The industrial chain is not yet mature and the cost is high.
- The construction of hydrogen refuelling stations is difficult.
- The construction cost of hydrogen refuelling stations is generally more than three times that of gas stations, and it is also higher than the construction cost of charging stations.
- Hydrogen is a dangerous flammable and explosive gas, and the difficulty of early construction, safety management and later maintenance is high, and it may also pose a certain threat to vehicle safety during use.
Hydrogen fuel cells have the advantages of a long cruising range and a short charging time. It is one of the directions of the industrialization and development of automobile companies.
It is expected that after the industrialization of hydrogen fuel cells in 2030, there will be a state of coexistence of hydrogen fuel cells and other batteries, and there may be a combination of hydrogen fuel cells and lithium batteries.
② Solid-state lithium-ion batteries
A solid-state lithium-ion battery is a type of battery that uses solid electrodes and a solid electrolyte. Compared to lithium batteries, solid-state lithium-ion batteries have the following advantages:
- High energy density
Solid-state batteries directly use li metal as the anode, which is light in weight and high in energy density to ensure the durability of the vehicle.
- Small size
The solid electrolyte additive replaces the separator and electrolyte additive of the traditional lithium battery, and the battery thickness is thin, small and light.
- High flexibility
The flexibility of solid-state batteries will also be significantly improved after thinning, ensuring that their performance is not degraded.
- High safety factor
The solid electrolyte additive are non-combustible, moisture-resistant, and the battery safety factor is higher than that of traditional lithium batteries. As the core component of EV, the energy density and scale of the battery directly determine the cruising range of electric vehicles.
Solid-state lithium batteries with high energy density have broad application prospects, but solid-state lithium batteries still have the following development resistance:
- Low ion conductivity
This hinders the movement of lithium ions between the cathode and anode of the battery, resulting in reduced speed and efficiency of lithium ion transmission.
- Poor interface contact
The contact area between the solid electrolyte additive and the cathode and anode is small, the interface impedance is large, and the battery cycle life and rate performance are poor, resulting in slow charging speed.
Without a complete industrial chain as a support for commercialization, it is impossible to prepare materials for larger volumes. Development is still relatively slow.
In summary, hydrogen fuel cells and solid-state lithium-ion batteries have certain technical advantages. There are top 10 lithium battery companies in the world and well-known car companies for layout, and the development prospects are good. However, subject to the pain points of technology and cost.
In the future, the battery industry is more likely to exhibit technological parallelism. Consumer trends require that future cars have the characteristics of economy, safety, environmental protection. In the current supply situation, lithium batteries and fuel cells have shortcomings. The combination of the two can complement each other.
Totally, it is expected that the future market pattern will be the coexistence of liquid lithium-ion batteries and other batteries, and each type of battery will have its own application fields.
Liquid lithium-ion batteries are less likely to be replaced. Moreover, in the short term, they are likely to maintain considerable market space, and the market space for electrolyte additive such as VC and FEC will not be greatly compressed.