Comparison of advantages and disadvantages between lithium ion battery and sodium ion battery. China’s batteries are mainly used in three industries, namely electric vehicles, energy storage and consumer electronics. Around these three directions, especially in recent years, the field of electric vehicles and energy storage has developed rapidly, focusing on lithium-ion batteries. Compared with lithium, sodium exists widely in nature and is relatively simple to obtain, but the early prototype of sodium ion battery has the characteristics of low performance and short life. Now, sodium ion battery has become a new promising direction. This article analyzes the advantages and disadvantages of lithium-ion battery and sodium ion battery.
Working principle and advantages of sodium ion battery
Principle: in the process of charge and discharge, Na + is embedded and removed back and forth between the two electrodes: during charging, Na + is removed from the positive electrode and embedded into the negative electrode through electrolyte; It is the opposite when discharging.
Advantages:
(1) The raw materials of sodium salt are abundant and cheap. Compared with the ternary cathode material of lithium-ion battery, the cost of raw materials is reduced by half;
(2) Due to the characteristics of sodium salt, it is allowed to use low concentration electrolyte (with the same concentration electrolyte, the conductivity of sodium salt is about 20% higher than that of lithium electrolyte) to reduce the cost;
(3) Sodium ions do not form an alloy with aluminum. Aluminum foil can be used as the collector for the negative electrode, which can further reduce the cost by about 8% and the weight by about 10%;
(4) Due to the discharge characteristics of sodium ion battery, no sodium ion discharge is allowed. The energy density of sodium ion battery is greater than 100wh / kg, which is comparable to lithium iron phosphate battery, but its cost advantage is obvious, which is expected to replace the traditional lead-acid battery in large-scale energy storage.

Comparison of advantages and disadvantages between lithium ion battery and sodium ion battery
1. The internal charge carriers of the battery are different. The lithium battery is charged and discharged by the movement and conversion of lithium ions between the positive and negative electrodes, while the sodium ion battery is charged and discharged by the embedding and stripping of sodium ions between the positive and negative electrodes. In fact, the working principles of the two are the same.
2. Because of the difference of ion radius, the performance of sodium ion battery is far lower than that of lithium ion battery; The negative electrode of lithium ion can make graphite, but sodium ion can hardly be de embedded / embedded in graphite, and the capacity is very small; Other carbon materials can reach up to about 300 MAH after treatment; The capacity of ions in the positive electrode is very small, only more than 100 MAH; The resistance of sodium ion intercalation / de intercalation in the positive and negative electrodes is very large, which comes from the large radius; Poor reversibility and large irreversible capacity loss.

Current situation of sodium ion battery industry in China
Sodium ion battery is an emerging industry. It may need more research and development to bloom the rose of time. At present, the industrialization of sodium battery is accelerating in China. In January 2019, the sodium ion battery independently developed by Liaoning XingKong sodium electric battery Co., Ltd. in Anshan recently entered the mass production stage. The world’s first sodium ion battery production line was put into operation, and the annual output value is expected to exceed 10 billion yuan after large-scale production.
From the perspective of industry, the industrialization of sodium batteries is still in its infancy. Many research results are only circulated in Colleges and universities and research institutes, and it will take some time before they are actually put into practice – some researchers even say that there is no chance for sodium ion batteries until the earth’s lithium reserves are exhausted. Like artificial intelligence technology, sodium battery may not be favored at the beginning and can only be circulated in the academic school, but it may have a mutation one day and quickly land in the industry. This is very possible, so sodium battery actually deserves the high attention of forward-looking entrepreneurs and investors.
Sodium ion battery is one of the important development directions of energy storage battery in the future. With the continuous progress of sodium ion R & D technology, the commercialization process of sodium ion batteries will continue to accelerate. Perhaps the layout of this field in advance is expected to take the lead in the field of new energy batteries. Of course, it seems too early to say that sodium ion batteries replace lithium batteries.