Winter is coming! And I’m sure people with a Lifepo4 battery bank are thinking about the effect of freezing low temperatures on their battery. You are about to find out from this article. So, let’s dive in.
Can LiFePO4 Batteries Freeze?
Yes, Lifepo4 batteries can freeze. Charging and storing a Lifepo4 battery at a below-freezing temperature can cause lithium plating. It is a process that lowers the capacity of a lithium battery, causing short circuits. Besides, the ABS casing of your battery can crack as well.
You must maintain the recommended temperature for charging and storing your Lifepo4 battery. Although these batteries can withstand very high and low temperatures, keeping them in a volatile temperature for too long can be detrimental. You should be careful about the ambient both while charging and storing.
Because of the low temperature, your Lifepo4 battery will freeze and cause damages you cannot come back from. Even if it works, you will get far less capacity than before.
Can LiFePO4 Batteries Be Stored Below Freezing?
According to a study, the Lifepo4 battery should not operate below 0°C. Maintaining that will ensure good health for your battery. The recommended storing temperature depends on the duration.
If you want to store your battery only for a few days, -5°C to +35°C is the right temperature. For storing up to 1 month, the temperature should be -20°C to +60°C. For up to 3 months, your battery should be within -10°C to +35°C.
And for an extended storage time, you must keep your battery at +15°C to +35°C temperature. So, you cannot store your lifepo4 battery below freezing temperature. You should also fully charge your battery before storage, as it self-discharges at a 2% rate per month.
Here’s a table showing recommended temperatures for storing the Lifepo4 battery at various duration.
| Duration | Temperature |
| For A Few Days | -5 to +35°C |
| Up to 1 Month | -20 to +60°C |
| Up to 3 Months | -10 to +35°C |
| Extended Period | +15 to +35°C |
Can LiFePO4 Batteries Be Charged Below Freezing?
No. You cannot charge Lifepo4 batteries at below-freezing temperatures for far too long. Generally, the recommended charging ambient for Lifepo4 battery is 5°C to +45°C. But you can safely charge this battery as low as 0°C. Going further below will have some dire consequences.
All Lifepo4 batteries come with an internal battery management system or BMS. When the BMS senses the outside temperature is below 0°C, it will disconnect the battery from charging and put it in sleep mode.
You will have to warm up your battery to reconnect or wake up from sleep mode. BMS does this only to protect the battery. Otherwise, the freezing temperature will damage your battery cells.
What Happens If a LiFePO4 Battery Freezes?
According to research by the SLAC National Accelerator Laboratory at the Department of Energy, storing lithium batteries at below-freezing temperatures will cause cracking in some parts of the battery. It will separate them from other parts, reducing electric storage capacity.
We have already learned that charging Lifepo4 batteries at freezing temperatures will cause plating. Freezing temperature slows down the chemical reaction inside the battery. So, eventually, the battery capacity will reduce as well. Plus, it will increase the discharge rate.
That’s why you shouldn’t keep your battery outside in the winter. Keep them somewhere safe where you can maintain the recommended temperature. Because storing and charging a battery in freezing temperatures will permanently damage it.
Final Thoughts
Like every other battery, Lifepo4 cells will freeze and cause irreversible damage if you keep them in frigid temperatures. You should use specially-made Lifepo4 batteries if the pace where you live is extremely cold.
References
1. Jizhou Li et al., (2021). Multiphase, Multiscale Chemomechanics at Extreme Low Temperatures: Battery Electrodes for Operation in a Wide Temperature Range.
2. L. Jiexun et al. (2012). Study on the effects of temperature on LiFePO4 battery life.
Eng. Matthew Joseph Nandirio is the Founder of walkingsolar.
After graduating from the University of Houston in 2002, matt started working as a Solar Electrical Engineer for several multi-national solar energy companies.
He has a wide range of experiences including solar system requirement analysis, planning, maintaining, debugging and even solar device development through research.
He now shares his 20 years of expertise through his articles on the walkingsolar website.
Further, he is also the author of two books on Solar Technology, “Solar Power for Villages” and “DIY Solar System for Dummies”.
