The impact of low winter temperatures on inverters and batteries

With the widespread application of photovoltaic energy storage systems in residential and commercial settings, the stability of these devices under varying climatic conditions is receiving increasing attention. Especially in winter, low temperatures can negatively impact the performance, lifespan, and system safety of inverters and batteries.

This article will start from the underlying principles, providing a detailed analysis of the effects of low winter temperatures on inverters and batteries, and offering practical solutions.

1.The impact of low temperature on inverters

Inverters, as the “core brain” of photovoltaic and energy storage systems, are primarily responsible for converting direct current (DC) to alternating current (AC) and for system control. The impact of low winter temperatures on inverters is mainly reflected in the following aspects:

Decreased start-up and operational stability

In extremely low temperature environments, the performance of electronic components inside the inverter (such as capacitors and power modules) may change, potentially leading to:

● Increased startup time

● Startup failure at low temperatures

● Instantaneous power fluctuations

Accelerated aging of internal components

Large temperature fluctuations (day-night temperature differences, frequent start-stop cycles) can easily cause thermal expansion and contraction of components, accelerating solder joint fatigue and potentially affecting the long-term lifespan of the inverter.

Heat dissipation and condensation risks

In winter, the ambient humidity is high, and when the temperature changes drastically, condensation may occur inside the inverter, increasing the risk of short circuits or corrosion, especially in outdoor or semi-outdoor installation scenarios.

2.The impact of low temperature on batteries

Compared to inverters, batteries are more sensitive to low temperatures, especially lithium batteries.

Battery capacity decrease

At low temperatures, the rate of internal chemical reactions slows down, resulting in a significant decrease in usable capacity:

● Capacity begins to decline significantly below 0°C

● Below -10°C, only 60%–70% of the rated capacity may be available.

Reduced charging and discharging efficiency

Low temperatures increase internal resistance, leading to decreased charging and discharging efficiency and reduced overall system energy utilization.

Low-temperature charging risks

For lithium batteries, charging at low temperatures may cause lithium deposition, which in severe cases can:

● Damage to battery structure

● Shorten battery life

● Increase safety hazards

Therefore, most lithium battery systems are equipped with low-temperature charging protection.

3.System response strategies under low winter temperatures

To ensure the system remains stable and safe during winter, optimizations can be made in the following aspects:

Choose equipment with a wide operating temperature range

Prioritize inverters and battery products that support operating temperatures of -20°C or lower to ensure normal operation in cold environments.

Plan your installation environment carefully

● Install indoors or in a sheltered location whenever possible.

● Avoid north-facing areas and areas exposed to strong winds.

● Ensure good ventilation to reduce the risk of condensation.

Equipped with battery heating or insulation solutions

For cold regions, we recommend:

● Energy storage batteries with built-in heating modules

● Insulated boxes or temperature control cabinets

● Ensuring the battery operates within a suitable temperature range

Optimize system control strategy

Through intelligent control of BMS and EMS:

● Limit low-temperature charging

● Adjust charging and discharging power appropriately

● Implement temperature monitoring and alarm

Strengthen winter maintenance and inspection

● Regularly check equipment operating status

● Pay attention to alarm information

● Clear snow to prevent ventilation obstruction

Заключение

The impact of low temperatures in winter on inverters and batteries cannot be ignored, especially the challenges to battery performance and safety.

Through proper selection, scientific installation, and intelligent management, the risks posed by low temperatures can be effectively reduced, ensuring the efficient and stable operation of photovoltaic energy storage systems during winter.