Cold Weather Effects on Solar Batteries

Every single solar install is different. Often there are a number of circumstances dictating their planning and installation. One that can be easy to overlook is the changing weather climates and the effect this can have on a system with a battery set up.

It’s this time of year that both users and installers can face the challenge of solar batteries battling against volatile temperature drops in our, sometimes, chilly Irish climate.

In this short guide, we explore the science behind the impact of low temperatures on batteries and provide a few ideas for installers to enhance system performance in cold weather.

The cold problem:

When temperatures drop, the chemical reactions within batteries slow down, leading to decreased capacity and discharge rates. For installers, this underscores the importance of selecting components resilient to Ireland's varying weather conditions AND, before an install even takes place, choosing the right area in which to install the batteries to ensure long-term system reliability (lofts can get pretty cold this time of year).

The Science:

Lithium-ion batteries work on a "rocking chair principle", with electrons and Li-ions moving during charging and discharging. But in colder weather, these types of battery can encounter challenges. The positive electrode becomes less active, reducing electric potential. Cold weather makes it tougher for lithium ions to move, increasing resistance. The SEI membrane also faces difficulties, making it harder for ions to pass through. Overall, the battery's efficiency decreases in the cold.

Charging batteries in cold weather, especially lithium-ion batteries used in solar systems, makes things even more challenging. Quick plating of lithium ions during charging can harm the separator inside the battery cell, potentially leading to reduced battery performance or even system failure.

Overall Effects of a ‘Cold Snap’

Essentially, when the temperature drops below 0°C batteries are likely to start losing their effectiveness. In some cases, this may see them fail to recharge and may require a manual intervention to get them operational again. Installers should exercise caution when charging lithium batteries in temperatures below freezing to avoid permanent damage. If you are in doubt, our customers can call the Failte Solar technical team for advice, we can even send you out charging packs, where needed.

Considerations to Combat Periodic Cold Weather

The problem is best avoided by taking a few things into consideration, check out some tips from our technical team:

Smart Charging Algorithms: Modern solar inverters often come with intelligent charging algorithms. These algorithms adjust charging voltage automatically based on the surrounding temperature, making the charging process more efficient, even in cooler Irish weather.

Choosing Heated Area Storage: Storing batteries in heated spaces, like utility rooms, minimises damage caused by cold temperatures, slowing down the chemical degradation process.

Using Battery Blankets: These blankets, designed for insulation, trap heat and shield battery cells from cold temperatures, ensuring better performance.

Opting for Insulated Storage or Battery Boxes: These compact units limit exposure to freezing air, providing additional insulation and preserving the heat generated by the battery components.

Conclusion:

When installing a system, especially in the summer when the weather is good, it’s easy to overlook cold weather impacts. We get a number of enquiries on this subject whenever we see an extreme temperature drop and whilst many manufacturers are correct in stating the battery is still operational at extremes, performance can be seriously diminished.

If you are having issues, let us know and the Failte Solar technical team will do all we can to help out.