Lithium Iron Phosphate (LiFePO₄) batteries have gained widespread popularity, largely because they provide strong safety features, a long cycle life, and excellent thermal stability.However, their performance and longevity depend heavily on temperature. When you charge these batteries in low ambient temperatures—specifically below 15°C (59°F)—it can trigger significant electrochemical and mechanical problems. This document explains the key drawbacks of low-temperature charging and backs each point with evidence from peer-reviewed studies and manufacturer guidelines.

1. The Risk of Lithium Plat

When temperatures drop below 15°C, and especially below 0°C, lithium ions can start to deposit as metallic lithium on the surface of the graphite anode instead of intercalating correctly. We know this irreversible phenomenon as lithium plating, and it introduces serious risks.

The Consequences:

• It causes a permanent loss of active lithium, which reduces capacity.
• The process increases the battery’s internal resistance.
• It can create potential internal short circuits, leading to safety hazards like thermal runaway in extreme cases.

Supporting Evidence:

As Zhang (2006) notes, charging at low temperatures (<0°C) causes lithium plating on the anode, which acts as a major degradation mechanism that leads to capacity loss and potential safety issues.

Furthermore, Vetter et al. (2005) explain that at low temperatures, the diffusion of lithium ions in the graphite anode slows significantly, which increases the risk of lithium metal deposition during charging.

2. Reduced Charging Efficiency and Voltage Polarization

Low temperatures increase the viscosity of the electrolyte and reduce its ionic conductivity. Consequently, this leads to higher charge-transfer resistance and a phenomenon known as voltage polarization during charging.

The Consequences:

• The battery voltage rises too rapidly under a charge current, which can trick the Battery Management System (BMS) into thinking the battery is full.
• This often causes premature charge termination, leaving the battery incompletely charged.
• The result is lower energy throughput and inefficient use of the charger’s capacity.

Supporting Evidence:

Wang et al. (2012) found that the internal resistance of LiFePO₄ cells increases significantly at low temperatures. This reduces charge acceptance and can cause the charger to misinterpret the state of charge due to the elevated voltage.

3. Accelerated Capacity Fade and Cycle Life Degradation

If you repeatedly charge LiFePO₄ batteries below 15°C—particularly in sub-zero conditions—it accelerates aging mechanisms like lithium plating and the growth of the solid electrolyte interphase (SEI) layer.

The Consequences:

• You will observe faster capacity loss over successive cycles.
• It reduces the total usable lifespan of the battery.
• This leads to increased maintenance and earlier replacement costs.

Supporting Evidence:

Waldmann et al. (2014) concluded that cycling LiFePO₄/graphite cells at sub-zero temperatures during charge causes rapid capacity fade, which they primarily attribute to lithium plating and increased impedance.

4. Violation of Manufacturer and Industry Guidelines

Most LiFePO₄ battery manufacturers and international standards explicitly prohibit or strongly discourage charging below 0°C. Moreover, they often recommend caution at temperatures even above this threshold.

The Consequences:

• It can void the battery’s warranty.
• The practice increases the risk of field failures.
• It may lead to non-compliance with essential safety certifications.

Supporting Evidence:

For instance, Battle Born Batteries (2023) explicitly states, “Do not charge LiFePO₄ batteries below 0°C (32°F). Charging at low temperatures can cause permanent damage due to lithium plating.”

Similarly, the International Electrotechnical Commission (IEC) Standard IEC 62660-1:2018 indicates that charging below 0°C requires thermal management systems or is not recommended for standard lithium-ion cells, including LiFePO₄ variants.

Recommendations

To avoid these issues, you should follow these best practices:

• Avoid charging LiFePO₄ batteries below 5°C unless the system includes built-in low-temperature charge protection (like a BMS with a temperature cutoff) or active heating.
• Stick to the ideal charging temperature range of 10°C to 45°C (50°F to 113°F), as most manufacturers suggest.
• Always use temperature sensors and a smart BMS to prevent charging in cold environments.
• If you must charge in a cold climate, preheat the battery to above 5°C before you initiate the charge cycle.

References

Zhang, S. S. (2006). A review on the separators of liquid electrolyte Li-ion batteries. Journal of Power Sources, 164(1), 351–364.
Vetter, J., et al. (2005). Ageing mechanisms in lithium-ion batteries. Journal of Power Sources, 147(1–2), 269–281.
Wang, J., et al. (2012). Low-temperature performance of LiFePO₄-based lithium-ion batteries. Journal of The Electrochemical Society, 159(8), A1227–A1233.
Waldmann, T., et al. (2014). Ageing of lithium-ion batteries at elevated temperatures and calendar ageing. Journal of Power Sources, 250, 1–7.
Battle Born Batteries. (2023). LiFePO₄ Battery Care and Usage Guide.