Sodium ion batteries and lithium-ion batteries are currently two popular rechargeable batteries on the market, with the main difference being the positive electrode materials used. Lithium ion batteries use metallic lithium, while sodium ion batteries use metallic sodium. In terms of current technology, lithium-ion batteries are currently a more common and mature technology, making them more popular in most applications. However, with the development of sodium ion battery technology and the reduction of costs, sodium ion batteries may become more common in future applications.

Below is a brief introduction to the advantages and differences between them:

Firstly, the energy density of lithium-ion batteries is higher than that of sodium ion batteries. This means that lithium-ion batteries can store more energy and provide longer battery life in batteries of the same size and weight. However, sodium ion batteries have a longer cycle life, which means they can undergo more charging and discharging cycles without performance degradation.

At the same time, sodium batteries can discharge to 0 volts without affecting battery life, while lithium batteries discharge to 0 volts causing copper dendrites, which can lead to lithium battery failure and irreversibility, significantly affecting lifespan. Normally, a residual voltage of about 10% must be maintained. In this regard, the advantages of sodium ion batteries are more obvious.

Secondly, in terms of safety, sodium batteries have higher internal resistance than lithium batteries. When there is thermal runaway and short circuit, the short circuit current of sodium batteries is smaller, the instantaneous heating is weaker, and the needle puncture test does not ignite or explode; Therefore, their battery chemical reactions have higher temperatures and greater chemical activity, which means they are more prone to safety issues during charging and discharging. In contrast, lithium-ion batteries have higher safety performance.

Then, the operating temperature range of sodium batteries is between -40 ° C to 80 ° C. At minus 20 ° C, the battery retention rate is also over 90%, while for lithium batteries, the battery retention rate drops to 70% at minus 20 ° C. The lower the temperature, the faster the battery retention rate drops. Moreover, under the same conditions, the charging speed of sodium batteries is twice or nearly twice that of lithium batteries, and they can be fully charged in about 15-20 minutes.

Finally, the cost of sodium ion batteries is relatively low because sodium is a more common element than lithium. However, the technology of sodium ion batteries is relatively immature, so the production cost is still high. Of course, if the technology of sodium ion batteries matures in the later stage, their cost may be lower than that of lithium-ion batteries.

So whether it’s sodium ion batteries or lithium-ion batteries, they both have their unique advantages and relative shortcomings. However, currently, due to the influence of technology, the development of sodium ion batteries still requires some time for precipitation, and lithium-ion batteries are already mature new energy batteries, so lithium-ion batteries are currently the mainstream.