Characteristics of electrolytes in lithium-ion batteries
Lithium-ion batteries utilize liquid, gel, or dry polymer electrolytes. The liquid form is a flammable organic type rather than an aqueous type; lithium salts react with organic solvents similar to ethylene carbonate solutions. Mixing the solution with various carbonates can provide higher conductivity and extend the temperature range. Other salts can be added to reduce outgassing and improve high-temperature cycling.
The role of electrolyte in lithium-ion batteries is like that of blood in the human body. It is the medium through which lithium ions move back and forth between the positive and negative electrodes. Without it, there would be no flow of electrons, and the battery would not exist. Therefore, its importance is self-evident.
The electrolyte plays a crucial role in transferring charge between the positive and negative electrodes, and should be conductive for ions and insulating for electrons. It has a significant impact on the cycle performance, operating temperature range, and battery durability of lithium-ion batteries. The composition of the electrolyte in lithium-ion batteries involves at least two aspects: solvent and lithium salt.
The fact that leading electrolyte manufacturers managed to control their gross profit margin decline to within 5% demonstrates the remarkable success of their accumulated efforts in supply chain systems, economies of scale, customer structure, and cost control. With the increasing production of electric vehicles and technological advancements driving performance improvements in power lithium batteries, demand for power lithium batteries is expected to exceed 200 GWh in 2020. Coupled with the steady growth of consumer batteries, this translates to a corresponding electrolyte market share of approximately 16 billion yuan.
Electrolyte is the ionic conductor that conducts electricity between the positive and negative electrodes of a battery, significantly impacting its charge-discharge performance (rate, high and low temperatures), lifespan (cycle storage), and operating temperature range. Currently, electrolyte performance is primarily achieved through the use and proportioning of different additives. The supply and quality of additives on the market do not currently affect electrolyte production. High-performance electrolyte formulations require companies to possess advanced technology and formulation expertise.
As demand for batteries in new energy vehicles and energy storage industries continues to grow, the production of lithium hexafluorophosphate is gradually returning to a balance between supply and demand. The return of lithium hexafluorophosphate prices will inevitably drive up electrolyte prices.
