With the development and application of sodium-ion batteries, there are increasing comparisons between them and lead acid batteries. Some people steadfastly stick to using lead-acid batteries, while others believe in the limitless potential of new technologies and look forward to the comprehensive adoption of sodium-ion batteries. Although we are unsure which type of battery you prefer, today, we aim to provide a simple summary and comparison.

What Is Sodium Ion Battery?

Sodium-ion batteries are rechargeable batteries, operating on a principle similar to lithium-ion batteries, where the charging and discharging processes involve the movement of sodium ions between the positive and negative electrodes. 

In recent years, there has been a resurgence of interest in sodium-ion batteries, primarily due to the realization that lithium resources are finite. To avoid being constrained by lithium resources, we must consider new energy storage solutions. So, are you aware of the advantages and disadvantages of sodium-ion batteries?

Sodium Battery Resource

Sodium Battery Resource

Advantage Of Sodium Battery

Abundant Resources

Sodium resources are much more abundant than lithium resources, with concentrations as high as 2.75% in the Earth’s crust and evenly distributed across various countries worldwide.

High Safety Performance

Sodium-ion batteries exhibit high safety performance, with better thermal stability compared to lithium-ion batteries.

Good Low-Temperature Performance

Sodium-ion batteries can discharge normally even in environments as cold as -40°C, maintaining around 80% capacity at -20°C. If you are in a cold region, they can address your concerns.

Excellent Rate Performance

Current sodium-ion batteries from manufacturers can charge up to 90% of their capacity within 20 minutes.

Environmentally Friendly

Sodium-ion batteries do not contain harmful heavy metals, making their raw materials environmentally friendly.

Disadvantage Of Sodium Battery

Energy Density

The energy density of sodium-ion batteries ranges from 110 to 160 Wh/kg, which is not low. However, compared to lithium batteries, they store relatively less energy, with significant room for growth. This gap is expected to narrow within 2 years, reaching parity with lithium batteries.

Lifespan

Similar to energy density data, the cycling lifespan of sodium-ion batteries is currently slightly inferior, but is projected to reach levels comparable to lithium iron phosphate battery within 2 years.

Volume and Weight

The lower energy density implies that sodium-ion batteries will also have larger volumes and weights.

Technological Maturity

The technology of sodium-ion batteries is rapidly advancing, but its commercial maturity has not yet reached the level of lithium or lead-acid batteries. Therefore, related products will require time and market space to grow and refine.

What Is Lead Acid Battery?

Lead-acid batteries are also rechargeable batteries, containing positive plates (lead dioxide), negative plates (lead), separators, battery cell containers, electrolyte (sulfuric acid solution), and terminals. 

Unlike sodium-ion batteries, they operate by chemical reactions between the positive and negative plates and the electrolyte to complete charging and discharging. Lead-acid batteries are a highly mature technology and find extensive applications across various fields.

Lead Acid Battery

Lead Acid Battery

Advantages of Lead Acid Battery

Cost Efficiency

As you are aware, the cost of lead-acid batteries is quite low, which is one of the reasons for their widespread popularity.

Technological Maturity

To date, the technology behind lead-acid batteries has become very mature, with a well-established supply chain and recycling system.

High Power Output

Lead-acid batteries can deliver high power output, making them popular in applications like hybrid electric vehicles requiring instant high currents.

High Recycling Value

The recycling system for lead-acid batteries is well-established, not only featuring a high rate of recycling but also high recycling value.

Disadvantage Of Lead Acid Battery

Low Energy Density

Lead-acid batteries have a lower energy density, possibly only 1/3 of that of lithium batteries, which correspondingly makes them larger and heavier.

Short Cycle Life

Due to the low energy density, the number of charge-discharge cycles is also fewer, especially with shorter lifespans during deep discharges. Therefore, you might need to replace the power source frequently.

High Self-Discharge Rate

A high self-discharge rate means that lead-acid batteries lose a significant amount of capacity when left idle over time, requiring regular charging.

Environmental Pollution

Lead-acid batteries contain the heavy metal lead and corrosive sulfuric acid. Improper handling of these batteries can easily cause harm to human health and the environment.

Sodium Ion Battery VS. Lead Acid Battery

After gaining a basic understanding of these two types of batteries, let’s list some comparison items to intuitively grasp the differences between them.

Sodium Ion Battery VS Lead Acid Battery

Sodium Ion Battery VS Lead Acid Battery

Rechargeability

Both sodium-ion and lead-acid batteries are secondary batteries, meaning they are rechargeable.

Voltage

Sodium-ion batteries: The nominal voltage is between 2.8 to 3.5V.

Lead-acid batteries: The nominal voltage is 2.0V, they can discharge down to 1.5V and charge up to 2.4V.

Raw Materials

The raw materials for both sodium-ion and lead-acid batteries are abundant and inexpensive.

Cost

Sodium-ion Batteries: Since this technology is still developing, its cost will continue to decrease as the scale of production expands. We can estimate its cost across three stages:

During the promotion period, the cost is higher than that of lead-acid batteries;

During the development period, the price can be on par with lead-acid batteries;

In the boom period, it will be lower than that of lead-acid batteries.

Lead-acid Batteries: Compared to sodium-ion and lithium-ion batteries, their cost is relatively low, around $0.3/Wh. However, due to the shorter lifespan of lead-acid batteries, they may need to be replaced more frequently.

Energy Density

Energy density refers to the amount of energy stored within a given volume or mass of a substance.

Sodium-ion Batteries: They have a relatively high energy density, which can reach 100~150Wh/kg, thus storing more energy.

Lead-acid Batteries: They have a low energy density, typically between 30~50Wh/kg, which means they store less energy in comparison.

Volume And Weight

From the above comparison, it is evident that sodium-ion batteries have a higher energy density. This means that for the same volume, sodium-ion batteries store more energy. To obtain the same amount of energy, lead-acid batteries require a larger volume, resulting in a heavier weight.

In summary: Sodium-ion batteries are lighter and more compact than lead-acid batteries.

Cycle Life

Sodium-ion Batteries: They have a longer cycle life, currently ranging from 2,000 to 6,000 charge-discharge cycles, and are capable of achieving 100% depth of discharge.

Lead-acid Batteries: Their cycle life is around 300 to 600 cycles, with a lifespan of 2 to 4 years, which is relatively short, especially during deep discharge conditions.

Temperature Performance

Sodium-ion Batteries: They have a wide operating temperature range, typically from -40°C to 60°C. They also perform well at low temperatures, maintaining about 80% of their capacity at -20°C, making them well-suited for use in extremely cold regions.

Lead-acid Batteries: They have a weaker temperature adaptation capability, with performance declining under extreme temperature conditions. Especially at low temperatures such as -20°C, their capacity can drop below 60%.

Charging Speed

Sodium-ion Batteries: They have excellent rate capabilities, capable of charging up to 90% of their capacity within 15 minutes, which is a very fast charging speed.

Lead-acid Batteries: They charge more slowly and have lower charging efficiency compared to sodium-ion batteries.

Safety

Sodium-ion Batteries: They have passed a series of safety tests and possess extremely high safety performance. They have good thermal stability and are not prone to spontaneous combustion or explosion. Additionally, the electrolyte is not highly corrosive, which reduces the risk of leakage.

Lead-acid Batteries: The chemical reactions in lead-acid batteries are relatively stable. However, they can release hydrogen gas when overcharged or damaged. Under certain conditions, a mixture of hydrogen and oxygen can lead to an explosion. Moreover, their electrolyte consists of sulfuric acid, which is highly corrosive and poses a risk of leakage.

Memory Effect 

Memory effect is usually associated with nickel-cadmium or nickel-metal hydride batteries. Batteries with memory effect are unable to utilize their full capacity, leading to reduced actual usage time. However, lead-acid batteries and sodium-ion batteries do not have a memory effect and are not affected by it.

Self-discharge Rate

Sodium-ion Batteries: They have a low self-discharge rate, generally between 1% to 5% per month. Therefore, even if sodium-ion batteries are left idle for an extended period, they can still retain a high capacity.

Lead-acid Batteries: They have a relatively high self-discharge rate of about 5% to 10% per month.

Maintenance

Sodium-ion Batteries: They require less maintenance and have lower maintenance costs.

Lead-acid Batteries: Flooded lead-acid batteries need regular checks of the electrolyte level and distilled water may need to be added when necessary. The terminals of lead-acid batteries also need to be cleaned regularly to prevent corrosion and oxidation from affecting the effectiveness of the connections. Furthermore, it’s important to ensure that they are regularly given an equalizing charge.

Environmental Protection

Sodium-ion Batteries: The raw materials of sodium-ion batteries are very environmentally friendly, but the environmental impact of the chemicals involved still awaits assessment. Additionally, the recycling system for sodium-ion batteries is not yet mature, and further technological development and improvement are needed.

Lead-acid Batteries: Lead-acid batteries contain toxic heavy metals, which can potentially pollute the environment during resource extraction and battery production. However, the recycling system for lead-acid batteries is relatively mature, though it is important to ensure proper handling to prevent pollution. Improper handling leading to liquid leakage can still cause serious environmental damage.

Application

Sodium-ion Batteries: Due to their higher energy density and longer lifespan, they are suitable for use in electric vehicles and large-scale energy storage systems. They also have the potential to replace lead-acid batteries as starter batteries for vehicles.

Lead-acid Batteries: Because of their low cost and high instantaneous discharge current, lead-acid batteries are commonly used for car starting, uninterruptible power supplies, and other industrial applications.

Can Sodium-ion Battery Replace Lead-acid Battery?

Many people are paying attention to this issue and hold different opinions. To be honest, although sodium-ion batteries have great potential, it will take a long time for them to completely replace lead-acid batteries. In fact, whether sodium-ion batteries can replace lead-acid batteries or not does not yet have a definitive answer. This is not a matter that can be resolved with a simple statement; it depends on multiple factors:

Technological Maturity

Sodium-ion batteries are still an emerging technology that has not been fully commercialized. To replace lead-acid batteries, it is necessary to first open up the market for sodium-ion batteries.

Cost Considerations

One of the reasons why lead-acid batteries are so popular is their low cost. Although sodium-ion batteries are abundant in resources and have the potential to be more cost-effective than lead-acid batteries, in order to replace them, it is necessary to maintain excellent performance while reducing costs.

Market Adaptability

Different markets and applications have different requirements for products. Sodium-ion batteries are more popular in the fields of electric vehicles and large-scale energy storage. Lead-acid batteries are currently more widely used in price-sensitive market applications.

Technological Innovation

In order for sodium-ion batteries to fully penetrate the market, they need to continue improving their energy density and cycle life.

Environmental Policy

Sodium-ion batteries are more environmentally friendly. If environmental protection policies become stricter, the use of lead-acid batteries may be impacted.

In summary, if sodium-ion batteries can make technological breakthroughs, improve energy density and cycle life, they may gradually replace lead-acid batteries in certain areas in the future. However, if they are to expand their applications and fully replace lead-acid batteries, they still need to continue to grow.

Finally, I welcome you to share your valuable ideas, so we can explore this topic together.

Recommended Sodium Ion Batteries

Sodium Cylindrical Cells:

3V 12Ah – 18650 

3V 10Ah – 32140 

3V 19Ah – 46145

Motorcycle Starter Batteries:

12V 2600mAh

12V 3900mAh

12V 5200mAh

12V 6500mAh

12V 7800mAh

12V 10400mAh

Sodium Batteries For Cars:

12V 57.2Ah