Precautions for LiFePO4 Batteries Charging
Be sure to READ and FOLLOW these important precautions for LiFePO4 batteries charging:
- NEVER charge LiFePO4 batteries with a charger not specifically compatible with LiFePO4 batteries!
- When the cell is first used, it MUST be fully charged and discharged for activating it and giving fully capacity.
- Always charge LiFePo4 batteries in an area with adequate ventilation.
- No matter what charge mode the battery is in, stop charging once the cell temperature exceeds the absolute charge temperature range.
- No matter what charge mode the battery is in, stop charging once the cell voltage exceeds the absolute charge voltage.
- When the LiFePO4 batteries are intended to be stored for a prolonged period of time (more than one month), the SOC of cells should be adjusted to around 50% periodically(every three months is recommended).
Why you should Charge the LiFePO4 Battery to Full Capacity before the First Use？
The LiFePO4 cells and batteries MUST be charged to full voltage level for activating it before assembling into a pack and before starting to be used. This way the cells will be fully charged and balanced before the first use of the battery pack.
Even in simple installations, it is important to make the first charging. Additionally to the first installation, we recommend to checking the cells of the battery pack from time to time and making the full balancing of all the cells, by means of the individual charging.
Can a Lead-Acid Charger charge a Lithium Battery?
Using SLA chargers to charge lithium batteries can damage, undercharge, or reduce the capacity of the lithium battery over time.
ONLY use a charger which can apply the “constant current/constant voltage”(cc/cv) charge technique with LiFePO4 voltage settings.
It is always important to match your charger to deliver the correct current and voltage for the battery you are charging.
Why you should not charge a LiFePO4 Battery below 0°C / 32°F?
LiFePO4 batteries should avoid charging below 0°C / 32°F prohibited (including standard charging, fast charging, and emergency charging), otherwise accidental capacity reduction may occur. The battery management system should be controlled according to the minimum charging temperature.
When attempting to charge a Lithium battery below 0°C / 32°F a chemical reaction referred to as “Lithium Plating” occurs. Lithium plating is caused by the charge current forcing the lithium ions to move at a faster reaction rate and accumulate on the surface of the anode.
When this chemical reaction occurs, the internal resistance of the battery increases and reduces the rate of chemical metabolism. This chemical reaction causes a permanent reduction of the battery’s capacity and will continue to reduce its capacity each time this reaction occurs.
The battery manufacturer will indicate the battery’s operating temperature (charging and discharging) on the product specification, and only need to strictly implement the installation standards.
How to store and maintain LiFePO4 Batteries during Winter?
You can take a few different steps to maximize the life of your lithium batteries during the cold winter months, including:
- Storing them in the proper temperature: Keep your lithium batteries in a place that does not get colder than 32 degrees Fahrenheit or warmer than 80 degrees Fahrenheit.
- Charging them regularly: Ideally, lithium batteries should never be completed uncharged, so it’s important to remember to charge your batteries in the winter months when they are most prone to quick loss of power.
- Cleaning them: Corrosion and dirt can cause the battery to lose charge faster, which decreases its lifespan, so it’s important to keep your lithium batteries clean. You can use a mix of water and baking soda for a gentle cleaning.
The Voltage change of the LiFePO4 Battery
During charging and discharging, there will be some voltage changes in LiFePO4 batteries. But the normal voltage range should be between 2.5V~3.65V, of which 3.65V is the maximum charge cut-off voltage. If it is larger than this value, then the battery may have problems. And 2.5V is the discharge cut-off voltage, smaller than this value means that the battery is over-discharging. But in most cases, the voltage of LiFePO4 battery will be maintained between 3.15~3.3V due to the stable discharge platform.
In addition, LiFePO4 batteries do not need float charging, and floating charging may even lead to overcharging of LiFePO4 batteries.