Lithium iron phosphate batteries, also known as LiFePO4 batteries, have become highly respected in the market in recent years.
Known for its long cycle life, light mass and excellent safety features, it has become one of the top choices for people looking for a highly durable battery.
However, questions often arise about the durability of these batteries. Just “How long will this battery last?”,“Do they need to be replaced once a year?”
In this article, we will answer these questions and give you some tips on how to store your Lifepo4 battery for optimum performance.
What Is a LiFePO4 (Lithium Iron Phosphate) Battery?
Lithium iron phosphate is a type of lithium-ion battery that uses lithium iron phosphate as the cathode material.
It is widely used in electric vehicles, solar energy storage, and other applications because of its high energy density, long life, high safety, and low cost.
What's more, it can be connected in series and parallel, making it easy to expand battery capacity and charge large devices continuously. For example, a 12V 100A battery (has 4 LiFePO4 cells) can be expanded by connecting four batteries in series to form a 48V 100A battery for golf carts and fishing boats.
Advantages of Lithium Iron Phosphate Batteries
Lithium iron phosphate batteries have many advantages, which we summarise for you as follows:
Higher Usable Energy Density
Lithium iron phosphate batteries can have a usable capacity in excess of 100% of their rated capacity. For example, a LiFePO4 battery with a rated capacity of 100 amp-hours, it can provide more than 100 amp-hours of capacity. In comparison, a 100 amp-hour lead-acid battery has a usable capacity of only 30 to 50 amp-hours.
Long Lifespan
Lithium iron phosphate batteries can be cycled more than 2,000 times after 100% average discharge. Even when the battery is discharged to 30%, it can still be used for 8,500 cycles. This means that lithium iron phosphate batteries have excellent cycling performance and are more durable than other types of batteries. In comparison, conventional lead-acid batteries only last 300-500 cycles. Due to its long life, lithium iron phosphate batteries are also an economically sensible choice. The 12 V lithium battery is the most classic type and is the most widely used.
Very Easy to Use
Compared to conventional lead batteries, lithium iron phosphate batteries have a long service life without extensive maintenance. Proper use and maintenance is particularly important in lead batteries, but not essential in LiFePO4. In addition, lithium iron phosphate batteries can be used with peace of mind until they are discharged to 100% without the need for a full charge, saving you a lot of worry.
Fast and Easy Charging
Lithium iron phosphate batteries have the advantage of fast charging and can be recharged to 100% capacity in less than an hour using a normal charger. With a powerful charger, charging times can even be reduced to half an hour. Compared to lead-acid batteries, even if the battery is not fully charged it will not damage or affect its performance, which is an important advantage of LiFePO4. In addition, this battery type does not require an absorption phase and therefore cannot be charged to the last 20% of the battery. With the battery management system, the battery is charged evenly, thus achieving an optimum charge. Once charging is complete, the battery is ready for immediate use, which provides flexibility and ease of use for this battery type.
High Temperature Resistant
Lithium iron phosphate batteries have excellent temperature resistance, with very little capacity loss even at extremely low temperatures. At temperatures as low as -20°C, LiFePO4 can still maintain a capacity of around 80%, much higher than the 30% capacity that lead-acid batteries can provide. In addition, lithium iron phosphate batteries can also function effectively in high-temperature environments.
Flat Discharge Curve
This type of battery has a nearly flat discharge curve, which means that the output voltage remains relatively constant whether the battery is fully charged or almost depleted. Even when the battery has been discharged to a very low charge, LiFePO4 is still able to deliver peak loads.
Lightweight and Compact
Compared to lead-acid batteries, lithium iron phosphate batteries are lighter, weighing only a quarter of the weight of their lead-acid counterparts. The compact size of these batteries makes them easy to place in a variety of spaces. In addition, as there is no risk of leakage, they can be placed in any location without fear of contaminating the environment. What's more, the space where the lithium iron phosphate batteries are placed does not need to be ventilated compared to lead-acid batteries.
Series and Parallel Expansion
In a series connection the voltage output of the battery pack increases, while in a parallel connection the capacity increases.
The combination of series and parallel connections allows greater flexibility to achieve a certain voltage and power with standard cells.
Lithium solar cells connected together will add their voltages together in order to run machines that require higher voltages. Allows expansion to 4 series and 4 parallel connections (max. 4S4P) for more capacity (max. 800Ah) and higher voltages (24V, 36V, 48V). 16 cells can be connected in series to form a 48v lithium golf cart battery.
How Long Does a LiFePO4 Battery Last?
LiFePO4 batteries can last between 5-10 years if properly maintained. It is important to note that LiFePO4 batteries can last even longer with correct maintenance. To avoid poor battery performance, it is important to avoid overcharging, otherwise, the battery's life may be shorter than expected.
LiFePO4 Batteries Applications
LiFePO4 batteries have the advantages of high energy density, long life, good safety and are suitable for a wide range of applications such as solar energy, caravans, golf carts, marine fishing boats, kayaks, etc. Curious if LiFePO4 batteries are also the solution for your application? Like lithium marine battery? Please feel free to contact our online sales!
What Factors Can Affect the Life of A Lithium Phosphate Battery?
The performance and life of Lifepo4 batteries are affected by several factors, mainly storage, maintenance and frequent charging. Your attention and maintenance can extend the life of your battery.
Here are some tips to extend the life of your Lifepo4 battery.
Don’t Overcharge
Overcharging is one of the main causes of battery damage, especially for rechargeable batteries. To avoid the dangers caused by overcharging, LiFePO4 batteries should be charged at less than 3.5 volts per cell and at an absolute maximum of 4.2 volts. Overcharging can be caused by improper installation of the system or the lack of a protection system.
Store Carefully
To protect the life of lithium batteries, they should be stored in a cool place. Lifepo4 batteries should be stored at temperatures ranging from -20°C to 25°C. For long-term storage, check the batteries regularly to avoid excessive discharge. High temperatures will reduce the capacity of the battery.
Don’t Over Discharge
Over-discharging and over-charging have the same effect on LiFePO4 batteries. It is recommended to keep the proper depth of charge and discharge (DoD) at around 70% and to avoid deep discharging. For 12V batteries, charge frequently and use a low voltage cut-off to avoid the battery voltage falling below 11.5V. Do not leave the battery discharged for long periods of time to prolong its life.
Clean the Battery Terminals
Dirty terminals can lead to reduced cell efficiency and failure. Cleaning with a wire brush will remove oxidation and improve conduction. Proper installation is also important, check the information on the packaging and check that the terminals are tight and in place every 1-2 months, otherwise heat may result.
How to Store Lifepo4 Batteries Correctly to Prolong Their Life?
To ensure the longevity of your Lifepo4 batteries, it is recommended to store them in a cool and dry location with a temperature range of approximately 15-20 degrees Celsius (60-68 degrees Fahrenheit). It is important to avoid exposing the batteries to extreme temperatures, as this can harm the battery cells and decrease their overall lifespan.
To extend the lifespan of your battery, take these few steps：
- Always use the correct charger
- Avoid constantly maintaining your LiFePO4 battery in a fully charged state.
- Make sure it has been stored correctly.
- Minimize the usage of battery-draining apps that consume a lot of power.
- Avoid exposure to high temperatures, as they can be damaged and shorten their life.
Conclusion
Lifepo4 batteries are commonly used in many electronic devices due to their durability. Although they may be more expensive, they provide good value for both regular and heavy use. These batteries are safe and designed for extended use, unlike lead-acid batteries. Proper storage and charging are important to ensure long battery life.
FAQs
Do LiFePO4 batteries degrade over time?
These systems use advanced BMS battery systems to store and supply energy in caravans, marine batteries, golf carts, and kayaks. However, over time, batteries degrade and lose capacity according to two different aging phenomena: cycling and calendar aging.
Can LiFePO4 last 20 years?
LiFePO4 batteries, also known as LFP batteries, are designed to last up to 10 years. At 80% depth of discharge, they can last for around 5,000 cycles, which is much longer than lead-acid batteries.
Is it OK to leave a LiFePO4 battery on the charger?
In contrast to lead-acid batteries, lithium iron phosphate batteries do not suffer damage in a partially charged state, so there is no need to worry about recharging them immediately after use. In addition, they do not have the so-called memory effect, so there is no need to use the battery until it is completely empty before recharging.
When should I stop charging LiFePO4?
If you are unable to disable the equalize function, you can instead adjust the voltage set to 14.6V or lower, which will essentially turn the charge cycle into a standard absorb cycle. Another option is to set the absorb voltage to either 14.4V or 14.6V and then discontinue charging once the battery has reached that voltage level. This approach can be beneficial and straightforward.
What are the disadvantages of LiFePO4?
The performance of lithium iron phosphate batteries can be affected in low-temperature environments and therefore need to be treated and protected with greater care. Also, problems often arise during the transportation and aging of LiFePO4 batteries. In addition, these batteries suffer from defects such as deep discharge and low energy density, making them unsuitable for use in small devices such as smartphones.
Why is LiFePO4 so expensive?
Although lithium iron phosphate batteries are more expensive to produce, they are a more affordable option in the long run because they have a longer service life. This is because the materials required to manufacture lithium iron phosphate batteries are more expensive than other battery types, leading to their higher initial cost.
How often should you charge a LiFePO4 battery?
If you do not discharge the LiFePO4 battery completely, it does not have to be charged immediately after each use. Also, if the battery is in a partially charged state (PSOC), it will not be damaged. You can recharge the LiFePO4 battery after each use or when it has been discharged to 80% of its charge (20% of the charge remaining).
Can you store LiFePO4 at 100%?
It is recommended that lithium batteries are stored indoors during the off-season to ensure their long-term preservation. Also, for lithium iron phosphate batteries, it is recommended to keep their storage charge at 50% or higher. If the battery is stored for a longer period of time, it is recommended to perform charge and discharge cycles at least once every 6 months to maintain its performance.
