[Complete Guide] Comparing the differences between LiFePO4 batteries and Li-ion batteries

If you want to power electronic devices, electric cars, off-grid power solutions or medical devices, choosing the right battery is crucial. Two of the most popular types of batteries currently available on the market are LiFePO4 batteries and lithium-ion batteries. In this article, we'll go over the differences and benefits of the two battery types and help you decide which one is best for your needs.

Part 1. LiFePO4 batteries

Lithium iron phosphate batteries (LiFePO4 batteries) are rechargeable lithium-ion batteries that use iron phosphate as the cathode material instead of cobalt, nickel or manganese. It is known for its high security, long service life and stable performance.

Compared to other lithium-ion batteries, LiFePO4 has a lower energy density but is less susceptible to thermal runaway, a dangerous condition in which the battery overheats and ignites. This makes LiFePO4 batteries ideal for applications where safety is a priority, such as: B. in electric vehicles, solar systems and portable electronic devices.

LiFePO4 batteries have a nominal voltage of 3.2 volts per cell and canbe connected in series or parallel to achieve higher voltages or capacities. They can also be charged and discharged with high currents without any significant loss of capacity or performance.

Part 2. Li-ion batteries

Lithium-ion batteries are rechargeable batteries that use lithium ions as the main component of their electrolyte. They are widely used in portable electronic devices, electric vehicles and other applications that require high energy density, low self-discharge and long service life.

Lithium-ion batteries consist of one or more cells, each containing a positive electrode (cathode), a negative electrode (anode), and an electrolyte that allows the movement of lithium ions between the electrodes during charging and discharging.

One of the key characteristics of lithium-ion batteries is their high energy density, meaning they can store a lot of energy in a small volume. This makes them ideal for portable devices and electric vehicles where space is limited. They also have a relatively low self-discharge rate compared to other rechargeable batteries, meaning they can hold a charge for an extended period of time without significant loss of capacity.

However, lithium-ion batteries also have some disadvantages. They are sensitive to high temperatures and overcharging, which can cause them to degrade quickly or even catch fire. They also have a limited lifespan as the number of charge-discharge cycles varies depending on factors such as temperature, depth of discharge and charging voltage.

Part 3. Complete comparison of LiFePO4 and Li-ion batteries

In this part, we conduct a comprehensive comparison between LiFePO4 and Li-ion batteries and analyze their differences in aspects such as DOD, voltage, self-discharge rate and more.

Depth of Discharge (DOD)

When it comes to depth of discharge (DOD), LiFePO4 batteries tend to perform better than lithium-ion batteries. LiFePO4 batteries can be discharged up to 100% without any negative impact on their service life.On the other hand, discharging a lithium-ion battery below the recommended DOD can result in permanent damage to the battery or even render it unusable.

Generally, the recommended DOD for a lithium-ion battery is around 80%, while the recommended DOD for LiFePO4 is typically around 100%. This means that LiFePO4 batteries can provide more usable energy than lithium-ion batteries because they can be fully discharged without damaging the battery. In addition, this means that you get more energy from a LiFePO4 battery than from a lithium-ion battery of the same capacity.

However, it is worth noting that a lithium-ion battery can still provide a high level of performance with a lower DOD compared to a LiFePO4 battery. It is important to consider the specific needs of your application and select a battery accordingly, as both LiFePO4 and lithium-ion batteries have their own unique characteristics and benefits.

Voltage

Li-ion and LiFePO4 batteries differ in their nominal voltage values. Li-ion batteries typically have a higher voltage rating range of 3.6-3.7V per cell, while LiFePO4 batteries have a voltage rating of around 3.2V per cell, requiring more cells to achieve the same output voltage .

For example, a standard 12V lithium-ion battery only requires 3 or 4 cells connected in series, while a 12V LiFePO4 battery requires 4 or 5 cells to achieve the same voltage level. Although LiFePO4 may result in slightly larger and heavier batteries, it offers several advantages such as greater safety, longer life and a wider operating temperature range.

It is important to note that although LiFePO4 batteries have a lower nominal voltage than Li-ion batteries, they can deliver a higher discharge current without a significant voltage drop. Due to a lower internal resistance, LiFePO4 batteries can deliver high power output with minimal energy loss.

Self-discharge rate

Self-discharge rate is the rate at which a battery loses its charge over time, even when it is not being used. This is a natural process that occurs in all battery types and can be influenced by various factors such as temperature, battery age and storage conditions. A battery with a higher self-discharge rate loses its charge more quickly and has a shorter lifespan than a battery with a lower self-discharge rate.

When it comes to self-discharge rate, LiFePO4 batteries have a significantly lower rate compared to Li-ion batteries.

On average, Li-ion batteries lose about 5-10% of their charge per month, while LiFePO4 batteries only lose about 2-3% per month.

This means that Li-ion batteries can lose up to 60% of their charge in a year of storage, while LiFePO4 batteries would only lose around 20-30% in the same period. This makes LiFePO4 batteries much more suitable for applications where long-term storage is required, such as in renewable energy systems or marine applications.

Energy density

In general, lithium iron phosphate batteries (LiFePO4 batteries) have a lower energy density than lithium-ion batteries (Li-Ion). LiFePO4 batteries have an energy density of around 120-160 Wh/kg, while Li-ion batteries can have an energy density of up to 200-300 Wh/kg or more.

One of the reasons for the lower energy density in LiFePO4 solar batteries is the larger size of their cathode particles, which results in a smaller surface area and fewer active sites for the storage of lithium ions during charging and discharging. Another reason is the lower voltage of LiFePO4 batteries (3.2V per cell) compared to Li-ion batteries (3.6-3.7V per cell), which means more cells are needed to power a given battery voltage to reach.

Weight

In general, LiFePO4 batteries tend to be slightly heavier than Li-ion batteries for a given energy capacity.

This is because LiFePO4 batteries have a lower energy density than Li-ion batteries, meaning they require more material (such as electrodes, separator, electrolyte, etc.) to store an equivalent amount of energy. Additionally, LiFePO4 batteries typically use thicker electrodes and separators, which increases their overall weight.

For example, a typical 12V 100Ah LiFePO4 battery used in electric vehicles or solar power systems may weigh around 30-40kg, while a similar Li-ion battery may weigh around 20-30kg. However, it is important to note that weight is only one factor to consider when selecting a battery and, depending on the application, other factors such as safety, cost, lifespan and operating temperature range may also be important.

Temperature range

Lithium iron phosphate batteries (LiFePO4 batteries) have a wider temperature range than lithium-ion batteries (Li-Ion). LiFePO4 batteries can typically operate in a temperature range of -20°C to 60°C (-4°F to 140°F), while Li-ion batteries typically operate in a narrower temperature range of -20°C to 45°C operated (-4°F to 113°F).

One of the reasons for this difference is that LiFePO4 batteries have more stable chemistry and are less prone to thermal runaway, a dangerous condition in which the battery overheats and ignites. This makes LiFePO4 batteries suitable for applications where high temperatures may occur, such as electric vehicles, renewable energy systems and military applications.

In contrast, Li-ion batteries are more sensitive to high temperatures and can deteriorate quickly or even catch fire when exposed to extreme temperatures or conditions. Therefore, Li-ion batteries are typically equipped with thermal management systems such as cooling fans or heat sinks to prevent overheating.

However, it should be noted that the specific temperature range of a battery also depends on other factors such as battery configuration, packaging and operating conditions. In general, both LiFePO4 and Li-ion batteries should be operated within the specified temperature ranges to ensure optimal performance and safety.

Lifetime

Lithium iron phosphate batteries (LiFePO4 batteries) have a longer lifespan than lithium-ion batteries (Li-Ion). Li-ion batteries typically have a lifespan of around 500-1500 cycles, while LiFePO4 batteries can typically last up to 2000-5000 cycles. With Class A cells, Timeusb LiFePO4 batteries can last up to 4000-15000 cycles.

One of the reasons for this difference is that LiFePO4 batteries have more stable chemistry and are less prone to degradation during charge and discharge cycles.The iron phosphate cathode material used in battery LiFePO4 is also more resistant to oxidation and corrosion, which helps maintain the battery's capacity and performance for a longer period of time.

In contrast, Li-ion batteries are more sensitive to cycling and may lose capacity over time due to factors such as electrode degradation, electrolyte breakdown, and internal resistance. This can lead to reduced runtime and performance, particularly under high loads or extreme temperatures.

However, it should be noted that the specific lifespan of a battery depends on many factors, such as: B. the depth of discharge, the charging voltage, the temperature and the usage behavior. In general, both LiFePO4 and Li-ion batteries can perform reliably for many years when operated within their specified parameters and properly maintained.

Security

Lithium iron phosphate batteries (LiFePO4 batteries) are generally considered safer than lithium-ion batteries (Li-Ion batteries), especially in certain applications where safety is a priority.

One of the reasons for this difference is that LiFePO4 batteries have more stable and robust chemistry compared to Li-ion batteries. The iron phosphate cathode material used in LiFePO4 batteries is more resistant to thermal runaway, a dangerous condition that causes the battery to overheat and ignite. This makes LiFePO4 batteries less prone to catching fire or exploding, even under extreme conditions such as overcharging, short circuits or mechanical abuse.

In contrast, Li-ion batteries are more susceptible to Thermal Runaway due to their higher energy density and more reactive cathode materials such as lithium cobalt oxide or lithium nickel manganese cobalt oxide. Thermal runaway can result in catastrophic battery failure, releasing toxic gases, flames and sometimes explosions.

However, it is important to note that both LiFePO4 and Li-ion batteries can be safe when properly designed, manufactured and operated within their specified parameters. Factors such as cell design, packaging, quality control, and safety features such as protection circuits and thermal management systems can all play a role in ensuring safe and reliable battery operation.

Cost

Li-ion batteries are generally cheaper and more common than LiFePO4 batteries. This cost advantage is due in part to the higher energy density of Li-ion batteries, which allows them to store more energy per unit of volume or weight, making them more cost-effective for certain applications.

LiFePO4 batteries, on the other hand, are typically more expensive due to their lower energy density and the use of more expensive materials in their construction. However, LiFePO4 batteries have a longer lifespan and higher safety standards than Li-ion batteries, which can result in lower long-term costs and lower risk for certain applications such as electric vehicles and renewable energy storage systems.

For example, a Timeusb 12V 200Ah Plus Deep Cycle LiFePO4 battery costs €529.99, has more than 4000 cycles at 100% DOD and can be used for more than 10 years , which means less than €2 per day.

Part 4.Application comparison of LiFePO4 and Li-ion batteries

LiFePO4 batteries and Li-ion batteries have different properties that make them more suitable for certain applications. Here is a comparison of applications for each battery type:

LiFePO4 battery:

Electric Vehicles (EVs): LiFePO4 batteries feature high energy efficiency, long service life and excellent safety features, making them a popular choice for electric vehicles.

Solar storage systems: LiFePO4 lithium batteries can withstand high temperatures and deep cycles and are therefore suitable for storing solar energy.

Marine and RV Applications: LiFePO4 batteries are lightweight, have a long lifespan, and are shock and vibration resistant, making them ideal for marine and RV applications motorhomes.

Li-ion battery:

Consumer electronics:Li-ion batteries have a high energy density and are therefore ideal for portable electronic devices such as smartphones, laptops and tablets.

Medical devices:Li-ion batteries are used in medical devices due to their high energy density and long service life.

Power tools:Li-ion batteries are light, powerful and can be charged quickly, making them ideal for use in power tools.

Conclusion

Both lithium iron phosphate (LiFePO4) batteries and Li-ion batteries have their own strengths and weaknesses and their suitable applications.

If you need deep-cycle batteries to power your RV, boat or home,Timeusbalways provides you with trustworthy batteries and excellent service.