Most batteries will operate, with varying degrees of effectiveness in the 5- 35 °C range so are fine for the autumn and spring operating months, however if you want a battery that will also operate efficiently in winter and summer you need to understand how temperature has an effect on a batteries operating capabilities.
The ambient weather temperatures have a large impact on the performance and on the life of most batteries and unfortunately, it’s a characteristic that isn’t often talked about.
The optimum temperature for most batteries to operate at is around 25°C and this is the temperature all battery testing is performed at. When temperatures vary, either up or down there is an effect on the performance and life of most batteries.
Depending on the chemistry of the battery different batteries will only operate optimally within a limited temperature range, so it’s important to understand this when purchasing or upgrading your battery for energy storage.
When the temperature starts to fall below about 15°C, depending on the battery chemistry, the electro-chemistry of the battery becomes sluggish and doesn’t perform as well. In fact, very few batteries operate below 0°C. This is relevant in many countries in Europe, the USA or Canada but not as relevant in most of Australia.
What is relevant to the Australian market is the other end of the scale with the hot weather temperatures, particularly those of 40°C or above. Over 35°C, again depending on the battery chemistry, the battery will not operate and will start to degrade. For this reason many batteries need to be kept in an air-conditioned environment which adds to the ongoing running costs of the battery and is something that needs to be taken into account when considering the LOC or lifetime cost of a battery. In the past, many installations have installed extra batteries, just to keep the air-conditioning running to keep the batteries cool.
Keeping a battery within its safe operating range is critical in the case of certain battery technologies as some batteries will catch fire if they get too hot. This is one reason that certain batteries have a BMS or battery operating system included to make sure that the battery can’t overheat. However, if this BMS fails or there is no power for an extended period of time there is the possibility of batteries catching fire or exploding. (Just another thing to take into consideration.)
The FIAMM Sodium Nickel Chloride or SoNick batteries are the only batteries that will really work reliably in temperatures over 40°C and these temperatures don’t cause the SoNick battery to deteriorate so won’t have a detrimental effect to the batteries longevity. This is particularly important in hot areas of Australia or in bushfire prone areas.