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LiFePO4 batteries, also known as lithium iron phosphate (LFP) batteries, are revolutionizing energy storage with their unmatched lifespan, efficiency, and safety. Unlike traditional lithium-ion batteries, they are cobalt-free, making them a more ethical and environmentally friendly choice.
Their high energy density, ability to withstand extreme temperatures, and superior cycle life make them an excellent alternative to lead-acid for a wide range of applications, including electric vehicles (EVs), off-grid solar systems, and portable power stations. Whether you’re looking for a reliable backup power source or a sustainable energy solution, LiFePO4 offers long-term value and performance.
What is a LiFePO4 Battery?
The lithium iron phosphate battery is a newer lithium-ion battery that uses LiFePO4 as the cathode and a carbon graphite electrode with a metallic backing for the anode. Since they use no cobalt, have a superior lifespan, are safer, less toxic, have a low self-discharge, and offer a better depth of discharge up to 100%, they’ve rapidly grown to become the most popular battery in EVs and renewable energy systems.
In fact, according to the International Energy Agency, in 2022, 30% of EVs used them. That rose to 39% in 2024; in China, over 70% of all new EVs are now using them. They are also used in all EcoFlow Portable Power Stations precisely for these reasons.
Now that they’re widely produced, they’re also becoming cheaper, resulting in their purchase cost declining significantly in recent years.
How Do LiFePO4 Batteries Work?
When we charge lithium batteries, a redox reaction occurs where the LiFePO4 compound splits into electrons, lithium ions, and an iron phosphate compound that remains. The lithium ions are extracted from the crystal lattice of the LiFePO4 cathode, and they migrate and become embedded into the carbon graphite anode. Electrons are also released and flow toward the anode, which creates electricity. This happens when we use solar panels to charge our EcoFlow DELTA Series Portable Power Stations to create clean energy from the sun that can be stored for later use. You can combine these power stations with EcoFlow Power Kits for a complete RV or off-grid build solution.
When we use these batteries to power our cars, appliances, or devices, that stored energy in the form of electrons is discharged to provide power, like when we use our EcoFlow DELTA 3 Plus to run our household appliances. During discharge, the redox reaction runs in reverse. Here, the lithium ions on the anode migrate back to the cathode, where the iron phosphate structure readily accepts the incoming lithium ions. This allows them to undergo more charging and discharging cycles than other models, providing superior longevity and further lowering costs to consumers who can reuse their batteries for 5-20 years compared to the 3-5 years of previous models.
Why Are LiFePO4 Batteries Important?
Wide Temperature Range
LFP batteries operate efficiently over a wider temperature range than most other models. They can function well in temperatures as low as -4°F (-20°C) and as high as 140°F (60°C).
Superior Lifespan
LFP batteries have the best charging cycles currently commercially available, being able to be charged and discharged between 2,500 and 5,000 times before noticeably losing capacity. This means they’ll also last longer, between 5 to 10 years on average, but often up to 15 years or more when using high-quality brands. All other traditional models max out at around 5 years or less.
No Maintenance
Unlike lead-acid models, LFP requires no maintenance to keep them running optimally. Their superior depth of discharge is up to 100%, which means you have to worry less about monitoring their charging. Still, recharging them when they drop to between 10 and 20% is good practice.
High Energy Density
LiFePO4 batteries have a higher energy density than most battery chemistries, so they can store more energy in smaller sizes and with less weight. This and their safety is why they are the preferred choice in renewable energy systems.
Cobalt-Free
Cobalt is a heavy metal primarily mined in the Democratic Republic of Congo, where labour conditions are inhumane and child labour is rife. It’s also toxic, hazardous waste when disposed of in landfills. While technically recyclable, cobalt recycling can be dangerous due to the chemicals and gases used. LFP is cobalt-free.
LiFePO4 vs. Lithium Ion Batteries: What’s the Difference?
LFP is technically a lithium-ion battery, and it works very similarly. However, instead of lithium-iron-phosphate, other lithium-ion models use cobalt, nickel, or manganese in their cathodes.
LiFePO4 batteries are a much safer alternative to lithium-ion batteries. They are not as prone to overheating and thermal runaway as their predecessors, significantly lowering the risk of fires and making them safer for use in homes and cars.
LFP models have a wider operating temperature range, from -4°F (-20°C) to as high as 140°F (60°C). On the other hand, lithium-ion performs best between 32°F (0°C) to 113°F (45°C), making them much less useful in our Canadian winters.
LFP also offers a superior lifespan thanks to undergoing thousands of charging cycles before their performance drops noticeably, compared to about 500 cycles or about 3-5 years for the average lithium-ion model. For instance, the EcoFlow DELTA Pro 3 with its LFP batteries can be charged 4000 times before its capacity is noticeably reduced after about 11 years of regular use.
The one area where traditional lithium-ion is ‘better’ is its slightly better energy density, so you can produce more energy with somewhat less weight. Still, the difference is small, and the other superior benefits of LFP still make them the best choice.
LiFePO4 vs. Non-Lithium Batteries
Next, let’s look at how LiFePO4 stacks up against non-lithium batteries.
Lead Acid
Lead-acid has been our primary storage battery for many decades. It uses a liquid sulfuric acid electrolyte prone to leaking and off-gassing. It has a high self-discharge rate, requires trickle-charging when in extended storage, and has a much lower depth of discharge; even deep-cycle lead-acid models can only discharge to 50% of their capacity. They also have much lower charge cycles—how often they can be discharged and recharged—typically in the 300 to 800 range.
In comparison, LFP typically has 3000 or more charging cycles, can be discharged to 100% of its capacity, and has a higher energy density, producing more energy with less weight. Finally, the newer lower production costs of LiFePO4 combined with the superior lifespan mean that lead acid is no longer the ‘cheap option’ it used to be. This is causing many to believe now that lead is dead and going the way of the dinosaurs.
Gel
Gel batteries are a more advanced type of lead acid that use a gel-like electrolyte made by mixing the sulphuric acid with silica to make it more viscous to solve some of the problems of traditional lead models, primarily concerns over leakage and off-gassing toxic fumes. They also offer a greater depth of discharge, up to 75%. This makes them better than their older counterparts, but they cannot compare to the performance of LiFePO4.
LFP batteries still have far more charging cycles, better energy density, better charging speeds, and superior safety. While some gel models may be slightly cheaper, you must replace your gel model 2-3 times before replacing your LFP model just once, offering superior sustainability and long-term savings.
AGM
AGM stands for Absorbed Glass Mat, but it is just another type of lead-acid battery. In this case, the liquid electrolyte is absorbed in a thin fibreglass matt and sealed, which prevents leaking and means they do not require the maintenance of flooded lead-acid models. This means they do not need trickle charging in storage, have a better depth of discharge at around 80%, and offer better charging cycles than traditional lead-acid. However, they still do not compare to LFP, which offers at least three times the charging cycles and can be discharged to 100% without damaging them, although it’s still good practice to recharge them when they have been reduced to 10-20% capacity.
Frequently Asked Questions
Use a dedicated charger for your battery with a battery management system to prevent overcharging, which could damage it. Then, you can use AC wall plugs, DC car plugs, a portable power station, or solar panels to charge it. Always remove it from the charger once full.
LiFePO4 batteries offer the longest lifespan of any commercially available battery, lasting between 5 and 10 years on average. However, high-quality models often last up to 15 years, and some may even last as much as 20 years.
LiFePO4 batteries are the superior choice for all renewable energy systems, including solar. They offer superior charging cycles, a low self-discharge rate, the greatest depth of discharge, and a superior lifespan. They’re also much safer than their predecessors, the lithium-ion batteries, which were more prone to thermal runaway.
Final Thoughts
LiFePO4 batteries stand out for their superior lifespan, safety, and efficiency, making them the best choice for energy storage solutions. Whether you’re powering an off-grid solar setup, an EV, or a home backup solution, they offer reliable performance with no maintenance required. Their ability to handle thousands of charge cycles, operate in extreme temperatures, and provide consistent power makes them a wise investment that will save you significant money in the long term. If you’re looking for a more sustainable battery, consider upgrading to a LiFePO4-powered EcoFlow Portable Power Station for dependable, long-lasting energy storage.