SMM5 March 30, recently, Ningde Times Chairman Zeng Yuqun said at the shareholders' meeting that Ningde Times will release sodium ion batteries around July this year. At the same time, it said that the current sodium-ion battery is an emerging battery technology, limited by its own technical level is still immature and the scale of the supply chain, so the current sodium-ion battery cost may be higher than lithium-ion battery.
As we all know, in the current industry, whether it is new energy vehicle power battery, or energy storage, small power field, lithium-ion battery occupies a dominant position without doubt, but what are the characteristics of sodium-ion battery? Will it have a huge impact on the lithium battery industry?
At present, sodium ion battery has the following characteristics:
First of all, in terms of the key electrochemical performance, the energy density of sodium ion is weaker than that of lithium ion. According to the data, the working voltage of sodium ion battery is 2.8-3.5V, and the energy density under the existing material system is only 100-150WP / kg. Although this data is higher than 2V and 40-50WH / kg of lead-acid battery, it is much lower than the current working voltage of 3.0-4.5V of lithium-ion battery. The energy density is 150-250WBG, but for the new energy vehicle power battery industry which pursues high energy density and high mileage, the energy density of sodium ion battery is too low to become the mainstream technology route.
In addition, the radius of sodium ion is much higher than that of lithium ion, which will also become an important factor limiting the development of sodium battery. First of all, the charge and discharge process of the battery is essentially a process of ion de-embedding, which also requires materials to store ions in both the positive and negative electrodes of the battery. In lithium-ion battery, the negative electrode is mostly graphite negative electrode. Because of its honeycomb structure, the graphite layer can well intercalate with lithium ion. However, because the radius of sodium ion is much higher than that of lithium ion, sodium ion can not completely enter the graphite structure, even if the embeddable hard carbon or other anode materials are used, it will greatly affect the overall energy density of the battery. Second, also because of the large radius of sodium ion, it is easier to lead to the volume expansion of electrode material than lithium ion in the process of charge-discharge intercalation, and some sodium ions can not be embedded smoothly in the process of embedding. This leads to irreversible battery capacity loss, battery attenuation rate increases, affecting the cycle life of the battery itself. In addition, the larger radius of sodium ion will also lead to its slow migration speed and low movement rate in the battery structure, which makes the charge and discharge cycle of sodium battery take longer than that of lithium ion battery in the same specification. Pull down the overall charge and discharge performance of the battery.
However, the biggest advantage of sodium ion battery lies in its cost. With the rapid development of new energy industry, the demand in areas such as 3C and small power has also increased in recent years, and the demand for upstream resources in the lithium battery industry as a whole is also increasing day by day. To a certain extent, the situation of resource run has been formed, and the prices of various raw materials such as lithium carbonate and cobalt sulfate have risen sharply. Among them, the average price of industrial carbon rose rapidly from 40, 000 yuan / ton in early December 2020 to 82000 yuan / ton in May, an increase of more than 50%, while cobalt sulfate also rose from 55000 / ton in 2020 to 94000 yuan / ton in mid-March. the uplink of raw materials has greatly raised the cost of battery manufacturing downstream, the overall supply chain of the industry has been steadily weakened, and the operations of some manufacturers have been greatly affected. Although this rise in raw materials is more caused by the imbalance between supply and demand in the industry caused by the sudden release of downstream demand, it is clear that the reserves of resources at the upstream end of raw materials are limited, and uneven distribution is also one of the important reasons for this incident. It is understood that the crustal abundance of lithium ion is only 0.0065%, and the amount of economically exploitable resources is limited, and there is a great difference between high and low quality. at the same time, there is a serious uneven distribution, among which high-quality resources are mostly concentrated in South America, Australia and other places. This also makes China, as a major consumer of lithium resources in the world, but highly dependent on the supply of imported raw materials. The abundance of sodium ion in the earth's crust is 2.75%, which is much higher than 0.0065% of lithium ion, and it is relatively widely distributed around the world, which makes sodium ion batteries have more advantages over lithium in terms of raw material cost after the scale of the industry.
Overall, at present, the impact of sodium-ion battery on the current lithium-ion battery industry is still limited. Although the sodium ion battery is still in the very early stage of industrialization, considering the characteristics of low theoretical capacity density, low charge and discharge efficiency and low matching with the current battery system, this may make the hope of large-scale application of sodium ion battery in new energy power battery more slim. But on the other hand, the relatively low cost of its own raw material makes it in some areas where the overall energy density and charge and discharge time of the battery are not high, and it is more sensitive to cost, such as energy storage, new energy low-speed cars may occupy a place, as a supplementary product of lithium battery.
