The lithium iron phosphate (LiFePO4) battery is a type of rechargeable battery that has gained popularity in recent years due to its long cycle life and high energy density. Lifepo4 battery are becoming increasingly common in a variety of applications ranging from electric vehicles to consumer electronics, and it is important to understand the best practices for charging and maintaining these batteries. This blog post outlines the basics of charging lithium ion batteries and offers tips to maximize their performance and longevity.
CHARGER INSPECTION
- Check the charger for any visible damage or signs of wear.
- Verify that the charger is the correct type and voltage for the lithium battery being charged.
- Ensure that the charger is properly connected to the battery, and that all connections are secure.
- Inspect the charger for any loose wires and connections.
- Check for any exposed wires, and if present, replace them immediately.
- Verify that the charger is not overheating and that it is functioning properly.
- Make sure that the charger is properly grounded and all safety features are in place.
- Confirm that the charger is not leaking any fluids.
- Check the charger for any defects or malfunctions, and replace it immediately if any are found.
CHARGING GUIDELINES
It is not necessary to charge LiFePO4 batteries after each use, as they are not susceptible to damage when in a partial state of charge (PSOC). However, when the battery has been discharged to 80% DOD (20% SOC) or if the Battery Management System BMS) has disconnected the battery due to low voltage (voltage will be <10V), it is important to remove the load and charge it immediately with a LiFePO4 battery charger.
4 Best Ways To Charge a LiFePO4 Battery
CHARGING TEMPERATURE
LiFePO4 batteries can be charged between 32°F and 113°F (0°C and 45°C) without needing temperature compensation for the voltage. With Diypow lithium iron phosphate batteries, the BMS (battery management system) is designed to protect the battery from both too low and too high temperatures. If the BMS disconnects due to low temperatures, the battery must be warmed up before the charging current can be accepted again. In the event of the BMS disconnecting because of high temperature, the battery has to cool down before the BMS can be charged again. For further information about the BMS' disconnect and reconnect values for low and high temperatures, please refer to the data sheet of your specific battery. Additionally, our LT series lithium batteries are equipped to be charged and discharged in temperatures ranging from -30°C to 55°C, featuring a built-in heating system that takes power from the charger to maintain an optimal charge without the battery discharging itself.
Series and Parallel Expansion of LiFePO4 Lithium Batteries
CHARGING LIFEPO4 IN PARALLEL
Connecting LiFePO4 batteries in parallel requires the voltage of each battery to be within 0.1V of one another. For 12V LiFePO4 batteries, a charging voltage of 14V – 14.2V is necessary; 24V batteries should be charged with 28V – 28.4V; 36V lithium batteries need 42V – 42.6V; and 48V LiFePO4 batteries require 56V – 56.8V. The following table summarizes the voltage requirements for each system voltage:
CHARGING LIFEPO4 BATTERIES IN SERIES
When connecting batteries in series, it is essential to ensure that each battery has a voltage reading within 0.05V of the others before putting them into use. This will reduce the possibility of an imbalance between them. If any battery in the set has a voltage reading that is more than 0.05V greater than the others, it is best to charge each battery independently to rebalance them. To avoid any further discrepancies, it is advised to recharge each battery individually periodically. For LiFePO4 batteries in series, a multi-bank charger that charges each battery individually is best to guarantee cells remain balanced. Alternatively, a 24V battery LiFePO4 charger or a 48V battery LiFePO4 charger can be used if you would like to charge your system as a whole.
CHARGING A LIFEPO4 BATTERY USING AN ALTERNATOR AND A DC TO DC CHARGER
Using a quality alternator may allow for successful charging of LiFePO4 batteries without modifications, though low-grade alternators with inadequate voltage regulation can lead to the BMS disconnecting the batteries, potentially damaging the alternator in the process. To prevent such damage, we recommend installing a voltage regulator or a DC to DC charger. This is the most secure solution for charging lithium with an alternator.
FUEL GAUGES FOR LITHIUM BATTERIES ARE AVAILABLE
If you are using a voltage-based fuel gauge designed for lead-acid batteries, it will not be able to accurately calculate the state of charge of LiFePO4 batteries. It is recommended to switch to a current-measuring fuel gauge instead in order to obtain an accurate reading.
Should you have any inquiries regarding this, please reach out to Diypow Technical Support at +86 13670210599.
FAQs
CAN SOLAR PANELS BE USED TO POWER A LITHIUM BATTERY?
Yes, solar panels can be used to power a lithium battery. You can power up our 12V LiFePO4 batteries with any type of charging device, provided that the voltage stays within the range of 14V to 14.6V.
CAN I CHARGE LITHIUM WITH A LEAD-ACID CHARGER?
No, you cannot use a standard AGM battery charger to fully charge a 12V LiFePO4 battery. The ideal charger should have a voltage between 14V to 14.6V, which is within the range of most AGM battery chargers. However, if your charger has a lower voltage, it may still charge the battery but it won’t be able to reach 100%. On the other hand, a charger with a higher voltage won't be able to charge the battery at all as the BMS will activate its high voltage disconnect feature. Wet cell or flooded battery chargers are not suitable either, as they usually have a higher voltage than what is required for a LiFePO4 battery.
HOW DO I STORE LITHIUM BATTERIES?
It is suggested to maintain LiFePO4 batteries at around 50% charge level when not in use. To avoid any damage, cycle the batteries every 6 months if not used for extended periods of time. Make sure that the battery is not discharged before storage. Trickle charging is not necessary. The optimal temperature for storing these batteries is between -5 to +35 °C (23 to 95 °F). For up to one month, the temperature can be between -20 to +60°C (4 to 140 °F). For 3 months, the temperature must be between -10 to +35°C (14 to 95 °F). If the storage period is extended, it is advised to keep the batteries in a temperature range of +15 to +35°C (59 to 95 °F). To ensure optimal performance, the batteries should be stored indoors during the off-season.
CAN I CHARGE LIFEPO4 BATTERY WITH SOLAR POWER?
Yes, it is possible to charge a Lifepo4 battery with solar power. Lifepo4 batteries are lithium-ion batteries that are widely used in many applications such as electric vehicles, power tools, and consumer electronics. These batteries are well suited to charging with solar power because they are able to store and deliver large amounts of energy, and their high cycle life makes them well suited for long-term use in solar applications. Solar power is an excellent way to charge Lifepo4 batteries, as they can be charged directly from the solar panel, eliminating the need for additional inverters and other equipment. Additionally, the solar panels can be used to charge the battery even when direct sunlight is not available, making it ideal for applications where the battery needs to be charged even during cloudy days.
CAN I CONNECT 12V LITHIUM IN SERIES?
Yes, you can connect up to four 12V batteries of the same model in series to obtain a higher voltage, however, do not connect lithium batteries in both parallel and series simultaneously. LiFePO4 batteries are designed to charge in series, so either a multi-bank battery charger that charges each battery individually or a 24V or 48V battery charger is recommended.
CAN I CONNECT 12V LITHIUM IN PARALLEL?
Yes, you can link up to four 12V batteries of the same type in parallel to increase the capacity. It is not recommended to connect lithium batteries in both series and parallel at the same time. For Diypow 24V and 36V lithium batteries, up to four units can be connected in parallel. For Diypow 48V LiFePO4 batteries, the number can be increased to 14 units as they are intended for bigger projects. Diypow lithium batteries also support charging in parallel.
CAN I CHARGE LIFEPO4 BATTERY WITH SOLAR POWER?
You can link up to four 12V batteries of the same type in parallel to increase the capacity. It is not recommended to connect lithium batteries in both series and parallel at the same time. For Diypow 24V and 36V lithium batteries, up to four units can be connected in parallel. For Diypow 48V LiFePO4 batteries, the number can be increased to 14 units as they are intended for bigger projects. Diypow lithium batteries also support charging in parallel.
ARE LIFEPO4 BATTERIES SAFE?
Yes, LiFePO4 batteries are generally considered safe. They do not contain any hazardous materials, so they are not prone to catching fire or exploding. They are also less likely to suffer from thermal runaway when charged or discharged at high currents.
- Longer life: LiFePO4 batteries can last for up to 2000 cycles or more compared to lead-acid batteries which can last for up to 500 cycles.
- Less weight: LiFePO4 batteries are much lighter than lead-acid batteries, making them an ideal choice for applications where weight is a factor.
- Higher energy density: LiFePO4 batteries have a much higher energy density than lead-acid batteries, which means they can store more energy in the same amount of space.
- Safer: LiFePO4 batteries are much safer than lead-acid batteries due to their chemical composition, which makes them less prone to thermal runaway and other safety risks.
If you possess a lead-acid or LiFePO4 charger and would like to ensure its compatibility, our battery experts can help. We can review your charger's user manual and verify the voltage parameters. Diypow offers 24/7 chat support to all our customers.
