The Difference Between Sodium Battery And Lithium Battery

Lithium battery is a primary battery that uses lithium metal or lithium alloy as the negative electrode material and uses a non-aqueous electrolyte solution. It is different from rechargeable batteries, lithium-ion batteries and lithium-ion polymer batteries. Because the chemical properties of lithium metal are very active, the processing, storage, and use of lithium metal have very high environmental requirements. Therefore, lithium batteries have not been used for a long time. With the development of microelectronics technology at the end of the 20th century, the number of miniaturized devices has increased day by day, placing high demands on power supplies. Lithium batteries subsequently entered the stage of large-scale practical use.

Sodium-ion battery vs. lithium-ion battery

The difference in charge carriers inside the battery is that lithium-ion batteries realize charge and discharge through the movement and conversion of lithium ions between the positive and negative electrodes, while sodium-ion batteries realize charge transfer by the insertion and extraction of sodium ions between the positive and negative electrodes. Yes, in fact, the working principles of both are the same.

The ionic radii of the two are different. This radius difference causes the performance of sodium-ion batteries to be far inferior to that of lithium-ion batteries. The negative electrode of lithium ions can be graphite, but sodium ions can hardly be deintercalated/embedded in graphite, and the capacity is very small.

Sodium and lithium belong to the same main group in the periodic table of elements, and their physical and chemical properties are similar. This makes the basic working processes of sodium-ion and lithium-ion batteries similar. However, sodium and lithium are still different in many ways, which leads to many differences between sodium-ion batteries and lithium-ion batteries.

First of all, the radius of sodium ions is larger than that of lithium ions, resulting in a small number of ions per unit volume and a small number of electrons that can be transferred during charge and discharge. The energy density of the same battery volume is naturally low, and the power storage is lower than that of lithium-ion batteries. (Energy density refers to the amount of energy stored in a unit volume or mass of matter. The greater the energy density of a battery, the more electricity can be stored in a unit volume or weight.)

In the selection of negative electrode materials, graphite with excellent electrochemical properties is usually used as the negative electrode of lithium-ion batteries. However, due to the large radius of sodium ions, they cannot be reversibly deintercalated on graphite, so hard carbon or alloys are usually used as negative electrode materials.

Judging from the performance comparison between the two, sodium-ion batteries perform poorly in terms of energy density and cycle life, but have obvious advantages in economy, safety and temperature adaptability.

Especially in terms of safety, sodium-ion batteries perform outstandingly. According to testing conducted by the China Automotive Technology and Research Center Co., Ltd. (CATARC), sodium-ion batteries do not emit smoke, fire or explosion when acupuncture is applied, and they do not catch fire or burn when subjected to short circuit, overcharge, over-discharge, extrusion and other experiments. They are safe. Significantly better than lithium-ion batteries.

At the same time, sodium-ion batteries have better thermal stability. The initial self-heating temperature of lithium-ion batteries is 165°C, while that of sodium-ion batteries reaches 260°C. In the ARC test, the maximum self-heating rate of sodium-ion batteries is significantly lower than that of lithium-ion batteries. In all current safety project tests, sodium-ion batteries have not caught fire.

Sodium-ion batteries are safer than lithium-ion batteries, mainly because sodium is the next cycle element of lithium and has more stable chemical properties, and the internal resistance of sodium-ion batteries is higher than that of lithium-ion batteries. In safety tests such as short circuits, the Produces less heat. In addition, sodium-ion batteries use aluminum foil with better stability as the negative electrode current collector, which can be completely discharged to 0V before transportation, and transportation safety is also higher.

Sodium-ion battery application areas

Sodium-ion batteries have their own differentiated advantages, but they have not yet been mass-produced and the cost is difficult to reduce. As the technology matures in the future, the cost advantage will become apparent, and it is expected to be widely used in fields such as energy storage, electric bicycles and low-speed electric vehicles (low-speed four-wheelers, electric tricycles, etc.).

1. Energy storage, lithium iron phosphate batteries and ternary lithium batteries have relatively high kWh costs, making it difficult to meet the large-scale commercial application of capacity-based energy storage. For energy storage, the ideal cost of electricity needs to be reduced to less than 0.3 yuan/kwh, and sodium-ion batteries are the most promising application.

2. Electric bicycles, there are currently 320 million electric bicycles in my country, of which 70% to 80% use lead-acid batteries. Lead-acid batteries are the most mature in industrialization, but they face serious environmental problems. Waste lead-acid batteries contain lead, lead-acid liquid and other substances, which seriously pollute the environment. At the same time, in terms of performance, cycle life and energy density are much lower than lithium batteries and sodium batteries.

Compared with lithium-ion batteries, sodium-ion batteries have lower costs, wider operating temperature ranges, and higher safety. Moreover, electric bicycles do not have as high energy density requirements as electric vehicles. Therefore, they are expected to be quickly applied to electric bicycles.

3. Low-speed electric vehicles and A00-class electric vehicles, low-speed electric vehicles are known as national vehicles. Because drivers do not need a driver's license and do not need to pay additional insurance fees for registration, they have a broad market in third- and fourth-tier cities and rural areas in my country. Due to the advantages in initial cost, most low-speed electric vehicles in my country previously used lead-acid batteries, and their replacement will be an inevitable trend.

The difference between sodium battery and lithium battery production process

Sodium-ion batteries and lithium-ion batteries are two common battery types, and there are some differences in their production processes.

First of all, there are differences between sodium-ion batteries and lithium-ion batteries in the preparation of cathode materials. Cathode materials for lithium-ion batteries usually require complex synthesis processes to obtain materials with high purity and specific structures. The preparation process of cathode materials for sodium-ion batteries is relatively simple, but it also requires controlling the performance and structure of the materials.

Secondly, the preparation of negative electrode materials is also one of the differences between the two. The negative electrode material of lithium-ion batteries is usually graphite, and its preparation process is relatively mature. The negative electrode materials of sodium-ion batteries can be diverse, such as hard carbon, soft carbon, etc., and appropriate preparation methods need to be selected for different materials.

There are also differences between the two in the selection and preparation of the electrolyte. The electrolyte of lithium-ion batteries needs to have good conductivity and stability to ensure battery performance. The electrolyte for sodium-ion batteries needs to consider its compatibility with the positive and negative electrode materials, as well as its efficiency in sodium ion transport.

Another important aspect in the production process is the selection and handling of the separator. The separator plays a key role in preventing direct contact between the positive and negative electrodes and ensuring the safety and stability of the battery. Sodium-ion and lithium-ion batteries may differ in separator materials and processing methods.

There are also some differences between sodium-ion and lithium-ion batteries in the battery assembly process. For example, the packaging of battery cells and the connection of electrodes need to be adjusted according to different battery characteristics.

In addition, parameters such as temperature, pressure, and time during the preparation process will also affect the performance of the two batteries. These parameters need to be optimized to obtain the best battery performance.

Overall, the preparation processes for sodium-ion and lithium-ion batteries differ in several aspects. These differences are mainly due to the different physical and chemical properties of sodium ions and lithium ions.