Properly storing LiFePO4 batteries is crucial to ensure that they have a long life and to prevent any potential hazards. Compared to traditional lead-acid batteries, these batteries are gaining more popularity because of their eco-friendliness, high energy density, and light-weight design. However, to optimize their benefits, knowing how to store them correctly is necessary.
People often store batteries without proper care, only to later find the battery short-circuited, fluid leaking, or not working for some reason.While most of these problems aren’t an issue for Lithium batteries, especially lithium iron phosphate (LiFePO4 or LFP), they still require certain precautions. This is especially true when the battery is disconnected and in storage.
Many people think that disconnected batteries do not pose any risk since they are not using any power. There is also a common perception that batteries do not lose any charge when not used.Unfortunately, these are misconceptions – completely wrong. Battery storage recommendations can vary from one manufacturer to another.This guide aims to provide in-depth information regarding the proper storage and handling of LiFePO4 batteries to extend their lifespan.
Why is Proper Storage for Li-ion Batteries and LiFePO4 Batteries Essential?
When a battery is not connected, no external appliance draws power from it. However, this does not stop the battery’s internal chemical reactions from occurring.
LiFePO4 batteries do not require as many safety measures as Li-ion batteries. LFP batteries use stable compounds of iron that do not create any toxic gases or explosive reactions. Even so, LFP batteries are an expensive investment. Correctly storing a LiFePO4 battery can ensure that the money you invested does not go to waste.
Many batteries come with a battery protector. This can help to store LiFePO4 batteries safely. However, as a point of note, a battery protector should not be used to store a battery in a discharged state. Protectors work well for batteries with at least 40% to 50% charge, as discussed in the sections below.
Main Tips for Storing Lithium Batteries
Disconnect Switch: Almost all manufacturers recommend storing lithium batteries after disconnecting them.For motorhomes and caravans, simply using the disconnect switch on appliances will not disconnect the battery pack. Some components remain active, for example, sensors, even when there is no external load to draw power. The correct way to disconnect the battery pack is by disconnecting the [+] and[-] wires to the battery pack terminals.
Unlike other types of battery packs, a lithium battery does not require trickle charge voltage. Therefore, there is no need to provide a power source when the battery is stored. LiFePO4 batteries have a 2% monthly self-discharge rate, so they retain most of their charge capacity during storage.
It is crucial to store a lithium battery away from any fire, radiator, or heat source. Batteries have chemicals that can heat up and explode when exposed to high temperatures for extended periods.When storing the battery, keep it away from conductive objects such as hairpins or other metals. These objects can cause a short circuit if they accidentally come into contact with both battery terminals.
The battery should not be used if it displays strange behaviour when taken out of storage. Strange behaviour includes any smells, fluid leaks, physical deformations, or other abnormalities.Places with high magnetic fields should be avoided when storing a LiFePO4 battery because magnetic fields can disorient or damage the battery management system aboard a lithium-ion battery.
HOW TO STORE LIFEPO4 BATTERIES?
How do I store my lithium battery? A question we receive from our customers on a daily basis, especially in the Winter season. The answer depends on the temperature you are storing the batteries in and the period of time. Here’s a summary of how to store your LiFePO4 battery:
- Recommended storage temperature: -5 to +35°C (23 to 95 °F)
- Storage up to 1 month: -20 to +60°C (4 to 140 °F)
- Storage up to 3 month: -10 to +35°C (14 to 95 °F)
- Extended storage time: +15 to +35°C (59 to 95 °F)
It is highly recommended to store lithium batteries indoors during the off-season. It is also recommended to store LiFePO4 batteries at about a 50% state of charge (SOC) or higher. If batteries are stored for long periods of time, cycle the batteries at least once every 6 months. Do not store batteries that are discharged.
DISCONNECT BEFORE STORING LIFEPO4
Many customers have main switches to disconnect the power to the batteries. We recommend that you take the extra step to ensure the batteries are TRULY disconnected. This is because many RVs would still have components running in the background, such as the C02 sensor, backlit stereo, or some other emergency sensor that may be bypassing the main disconnect switch. The best thing to do when you’re storing the batteries is to physically disconnect the main positive and negative wires from the lithium batteries. This will ensure that during storage time, the battery is not being discharged and that you have plenty of charge in the LiFePO4 batteries when you use them again. Make sure you always use a lithium charger and not one meant for other battery chemistries.
LiFePO4 batteries have a low self-discharge rate of 2% a month. This means that when a lithium battery is stored, it’ll lose 2% of its charge capacity every month. In order to prevent a higher rate of discharge, we recommend disconnecting all power draw from your batteries. When you store LiFePO4 batteries, it is important that you store them with a state of charge (SOC) of 50% or higher. A higher state of charge is recommended when storing for an extended period of time. If you want the battery to retain a good level of charge after the storage period is over, you should charge them to 100% and store them in that fully charged state.
HOW TO STORE LIFEPO4 WITH SYSTEM
If you are storing your LiFePO4 batteries along with your entire system; such as your charger and inverter, we recommend using a battery guardian, which protects LiFePO4 batteries by disconnecting them from parasitic loads once a voltage of 11.5V is reached. If you do not have a disconnect switch installed, it is recommended that you remove the main battery connections. It is okay that the charger is disconnected while the batteries are stored since LiFePO4 batteries do not require a trickle charge.
HOW TO STORE LIFEPO4 IN COLD WEATHER
Lithium cells are not affected by extreme temperatures if the battery pack is not being used. We do not recommend storing lithium batteries in very cold temperatures for extended periods of time because that could cause the ABS casing of the battery pack to potentially crack. In addition to this, hot temperatures beyond 60°C (140°F) can cause damage to other components in the battery pack, therefore it’s best to always avoid high temperatures for long periods of time. te. It is always recommended to store lithium batteries indoors and at room temperature.
RISK OF NOT CHARGING BEFORE BATTERY STORAGE
There are major consequences if you store your LiFePO4 battery without a charge. Because of the 2% self-discharge rate, the battery can become over-discharged. The level of discharge can potentially go below what the BMS can protect. This is why it is very important to charge your lithium battery before you store it. It is highly recommended that you also store the lithium battery at room temperature, especially when storing them for an extended period of time. Refer back to the first paragraph of this article to see how long you can store LiFePO4 at various temperature ranges. Over-discharging the cells due to storage without a charge can cause permanent damage and void your 10-year battery warranty. The Solorage built-in BMS logs all activities performed on the battery including storage. Every charge and every discharge is recorded, along with various other factors, such as temperature.
COLD WEATHER PERFORMANCE
When discharging LiFePO4 batteries in extremely cold temperatures (less than 0 degrees Celcius), there is potential capacity loss. For example, a 12V 100Ah LiFePO4 battery may deliver only 90Ah, 80Ah, or even 70Ah in freezing temperatures, depending on how cold it is. This is natural for LiFePO4 chemistry and it’s only temporary. The full capacity will recover when the battery warms back up. At 0°C, a CLI100-12 battery (12V 100Ah) delivers about 80 amp-hours. At -20°C, the capacity that the battery can deliver drops to about 70 amp-hours. Charging LiFePO4 batteries in freezing temperatures can cause lithium plating, a dangerous phenomenon that can cause short-circuiting. This is why all Solorage LiFePO4 batteries have a built-in BMS which protects against cold weather charging. The BMS is also responsible for protecting against other factors including:
- High-temperature charging
- Overcharge
- Over-discharge
- Internal short circuits
Tips for Extending LiFePO4 Battery Lifespan
To maximize the lifespan of LiFePO4 batteries, here are some tips to follow:
1. Store and use the battery in a moderate temperature range
As mentioned earlier, temperature plays a significant role in the lifespan of LiFePO4 batteries. Therefore, it is essential to store and use the battery in a moderate temperature range to ensure optimal performance and longevity.
2. Charge and discharge the battery at a moderate rate
Charging or discharging the battery too quickly can cause heat buildup and damage the battery’s internal components. Therefore, it is recommended to charge and discharge LiFePO4 batteries at a moderate rate to extend their life.
3. Avoid over-discharging the battery
Over-discharging the battery can cause irreversible damage to the battery’s chemistry and reduce its overall lifespan. Therefore, it is recommended to keep the DOD of LiFePO4 batteries below 80% to maximize their lifespan.
4. Avoid storing the battery at full charge
Storing the battery at full charge for an extended period can cause stress on the battery’s internal
Frequently Asked Questions (FAQs)
What are Lithium LiFePO4 batteries?
Lithium-ion batteries are the most common type of rechargeable battery in use today. They have a high energy density and power and are lightweight. There are many lithium-ion batteries, but the most common is Lithium LiFePO4. It has a higher energy density than other lithium-ion batteries, which means it can store more electricity for a given weight.
What is the most important thing about storing lithium-ion batteries correctly?
A lithium-ion battery is a rechargeable type commonly used in portable electronic devices. Li-ion batteries are the most popular rechargeable batteries found in laptops and cell phones. The most important thing about storing lithium-ion batteries is keeping them out of direct sunlight, which can cause the battery to overheat and even ignite.
How do I maintain my lithium-ion Batteries?
By charging it correctly and taking good care of it, you can extend the life of your lithium-ion battery. If you’re going to store lithium batteries, charge them to 50% and ensure they’re holding their charge every two to three months.
How do you store LiFePO4 batteries when not in use?
The best way to store the battery is to physically disconnect the main positive and negative wires from the LiFePO4 lithium battery. This will ensure that the batteries will not discharge during storage, and when you use them again, they will have enough power.
Is it best to store lithium batteries fully charged?
Lithium batteries should be kept at around 40-50% State of Charge (SoC) to be ready for immediate use – this is approximately 3.8 Volts per cell – while tests have suggested that if this battery type is kept fully charged the recoverable capacity is reduced over time.
How do you store lithium-ion batteries long term?
Lithium batteries are not likely to suffer any noticeable damage unless you store them at consistently extreme temperatures such as under 20 degrees or over 100 degrees Fahrenheit. Nevertheless, keeping them at a comfortable temperature is ideal for battery longevity.
How long can a lithium battery sit unused?
Non-rechargeable lithium batteries are the longest lasting primary battery. They can have a shelf life of 10-12-years when stored at room temperature. The shelf life can be determined by the battery’s manufacturing process and chemical composition.