FAQ

Lithium batteries mainly achieve charging and discharging through the movement of lithium ions between the positive and negative electrodes. During charging, lithium ions are extracted from the positive electrode, pass through the electrolyte, and are inserted into the negative electrode. During discharging, lithium ions are extracted from the negative electrode, pass through the electrolyte, and return to the positive electrode. In this process, electrons flow in the external circuit to form an electric current, thus enabling the battery to supply power to the outside.

Try to avoid overcharging and over-discharging the batteries. Use the original charger. When the battery level shows around 20% - 30% remaining, you can start charging. Try not to unplug the charger halfway during charging until the battery is fully charged. At the same time, avoid charging in a high-temperature environment.

The electrolyte of lithium polymer batteries is solid or gel-like, and their shape can be customized. They are thinner, lighter, and more flexible, making them suitable for devices with shape requirements such as smart watches. The electrolyte of lithium-ion batteries is generally liquid. They have a relatively high energy density, relatively mature technology, and a wide range of applications, such as common laptop computer batteries.

The unit of capacity for lithium batteries is usually milliampere-hours (mAh) or ampere-hours (Ah). It represents the amount of electricity that the battery can release under certain discharge conditions. For example, a 1000 mAh battery can continuously discharge for 1 hour when discharged at a current of 1000 mA.

Used lithium batteries contain harmful substances such as heavy metals and cannot be discarded casually. They can be sent to specialized battery recycling institutions. These recycling institutions will use professional methods to extract valuable materials from the batteries (such as lithium, cobalt, etc.), and at the same time conduct environmentally friendly treatment of the harmful substances.

In a low-temperature environment, the conductivity of the electrolyte inside the lithium battery deteriorates, the diffusion speed of lithium ions slows down, and the internal resistance of the battery increases. This leads to a faster drop in voltage during discharging, a reduction in available capacity, and a slower charging speed.

The charging speed is mainly related to the power of the charger and the performance of the battery itself. A charger with high power can provide a higher charging current, speeding up the charging of the battery, but the battery itself also needs to support high-current charging. At the same time, the temperature of the battery also affects the charging speed. Too high or too low a temperature is not conducive to fast charging.

Currently, researchers have been working hard to improve the energy density of lithium batteries. They are starting from aspects such as material innovation (such as the research and development of high-nickel ternary materials, solid-state electrolytes, etc.) and battery structure optimization. Although there has been progress, many challenges remain, and it is difficult to achieve a significant leap-like improvement in the short term. However, in the long run, with the breakthrough of new technologies, it is expected to be gradually and significantly improved.

The common reasons are as follows: First, overcharging and over-discharging, exceeding the normal voltage range of the battery, resulting in gas generation and expansion inside the battery. Second, poor battery quality and defective production processes, such as loose encapsulation. Third, using or charging the battery in a high-temperature environment for a long time, accelerating the chemical reactions and aging inside the battery, promoting the accumulation of gas, and causing the swelling phenomenon.

In principle, it is not recommended to use lithium batteries while they are being charged. On the one hand, the battery itself generates heat during charging, and using it will also generate heat. The double heat generation easily makes the battery temperature too high, affecting the battery life and posing a safety hazard. On the other hand, it will interfere with the normal operation of the battery's charge-discharge management system. However, some devices are now designed with corresponding protection mechanisms that can reduce the adverse effects to a certain extent, but it is still not recommended to do this for a long time.

They have high safety and strong thermal stability, and are not prone to serious accidents such as burning and explosion. They have a long cycle life, and the performance attenuation is slow after many charge-discharge cycles. They have a relatively low cost and abundant raw material resources. However, their energy density is slightly lower than that of ternary lithium batteries, and their low-temperature performance is slightly worse. But they are widely used in fields such as energy storage and commercial vehicles where high safety and long life are required.

In terms of appearance, the color and texture of the shell of a refurbished battery may be uneven, with signs of wear or repainting. The identification stickers are blurred and irregular, and there are signs of alteration on the nominal parameter inscriptions. In terms of performance, the actual capacity is far lower than the nominal capacity, it charges quickly but has a short usage time, the self-discharge speed is abnormally fast, and the internal resistance of the battery is much larger than that of a new product. These characteristics can be used for auxiliary judgment.

In high-altitude areas, the air pressure is low and the oxygen content is low. The heat dissipation efficiency of lithium batteries changes, and they are more likely to generate heat during use. Avoid using them continuously and intensively for a long time to prevent overheating. At the same time, due to the difference in air pressure, the pressure on the battery shell is different from that on the plain. Prevent external physical squeezing and collision to reduce the risk of battery failure. Also, try to choose a suitable temperature environment for charging.

Now, pre-activation treatment has been completed for lithium batteries produced by regular manufacturers before leaving the factory. For the first use, there is no need for special activation operations like those for early nickel-cadmium batteries. Just charge and use them normally. However, try to fully charge the battery for the first time, and then charge and discharge it according to the specifications later, which will help the battery enter the best performance state and extend its service life.

The working principles of sodium batteries and lithium batteries are similar. Both achieve charging and discharging through the movement of ions between the positive and negative electrodes. The difference is that sodium batteries use sodium ions, while lithium batteries use lithium ions, and the positive and negative electrode materials and electrolytes used by the two are also different.

The advantages of sodium batteries include rich sodium resources and low price. Theoretically, the cost is lower than that of lithium batteries. They have high safety, large internal resistance, and generate less instantaneous heat when short-circuited. The temperature of thermal runaway is higher than that of lithium batteries. They have a wide working temperature range and can work normally in the temperature range from -40°C to 80°C. The capacity retention rate is close to 90% in an environment of -20°C, and the low-temperature performance is better than that of lithium-ion batteries. There is no over-discharge situation, and the positive electrode can be discharged to 0V without affecting subsequent use, making them suitable for long-term storage and long-distance transportation.

The disadvantages of sodium batteries mainly include lower energy density. Both the mass energy density and the volume energy density are significantly lower than those of lithium batteries. The cycle life is relatively short. The industrial chain is not yet perfect. The commercialization of battery-grade raw materials such as positive and negative electrode materials and electrolytes is not yet mature. The technical maturity is not high, resulting in the actual cost being much higher than the theoretical cost. The charging rate may be lower than that of lithium-ion batteries. They are sensitive to temperature, and high or low temperature environments may affect their performance and life.

Currently, the energy density of sodium batteries is far lower than that of lithium batteries. However, researchers have been working hard to improve its energy density, starting from aspects such as material innovation and battery structure optimization. In the future, with the breakthrough of new technologies, it is expected to be gradually improved, but it is difficult to reach the level of lithium batteries in the short term.

The application scenarios of sodium batteries include the energy storage field, such as solar photovoltaic energy storage, etc. Their cost advantage and safety can be utilized. In the field of low-speed electric vehicles, such as electric two-wheelers, etc. They can also be applied in subdivided fields such as starting power sources for commercial vehicles, power supply for low-voltage loads, emergency power supply, and electric tools, playing their characteristics of being resistant to over-discharge, having excellent low-temperature performance, and being suitable for high-power charging and discharging.

Currently, the cost advantage of sodium batteries has not been fully reflected. According to the calculation data of Everbright Securities, sodium batteries will not have an advantage in cost in 2024, and can only barely gain an upper hand in 2025. However, this also depends on various factors such as the maturity of the industrial chain, technological progress, and scale effect.

The production process of sodium-ion batteries is similar to that of lithium-ion batteries, mainly including electrode sheet manufacturing and battery assembly and other links. However, sodium-ion batteries can use aluminum foil as the negative electrode current collector, and the positive and negative electrode sheets can use the same aluminum tab, and the related processes such as tab welding can be simplified.

The development of sodium batteries is of great significance for the new energy industry. On the one hand, it can reduce the dependence on lithium resources and ensure the supply chain security of the new energy industry. On the other hand, the cost advantage and performance characteristics of sodium batteries make them have broad application prospects in fields such as energy storage and low-speed electric vehicles, helping to promote the diversified development of the new energy industry.