The Relationship Between Temperature and UPS Batteries

Power Control
03 Aug 2023

‘The World Meteorological Organisation (WMO) has warned the global temperature is set to break a key limit for the first time within the next five years – and there is a 98% chance of the hottest year on record being broken during that time.’1 Warmer ambient temperatures can have a detrimental effects to uninterruptible power supplies if correct measures aren’t taken to protect them and their batteries.

To maximise the performance and longevity of UPS batteries, it is essential to acknowledge the significant impact that temperature can have on their overall functionality. This blog covers the effects of temperature of UPS batteries and provides invaluable insights to optimise their performance and extend their lifespan.


Understanding the Relationship Between Temperature and UPS Batteries

Temperature has a profound influence on the operational efficiency and overall lifespan of UPS batteries. As temperature varies, it directly affects the chemical reactions occurring within the battery cells, leading to critical changes in performance. Typically, UPS manufacturers recommend that UPS batteries operate in an ambient temperature ranging between 20C and 25C as this provides the optimal balance for the battery chemistry and performance. To comprehend the impact of temperature on UPS batteries, there are two crucial aspects: charging efficiency and battery life.


Charging Efficiency

Temperature significantly affects the charging efficiency of UPS batteries. High temperatures accelerate chemical reactions within the battery cells, causing them to charge more rapidly. However, this increased charging speed comes at a cost. Elevated temperatures also promote a higher rate of self-discharge, which can deplete the battery's stored energy even when not in use. Moreover, the increased heat generated during rapid charging can raise the internal temperature of the battery, potentially leading to thermal runaway and irreversible damage.

On the other hand, low temperatures impede the charging process. As temperatures drop, the battery's internal resistance increases, reducing its ability to accept a charge efficiently. Consequently, the charging time may lengthen, prolonging the time it takes to restore the battery to full capacity.


Battery Life

The lifespan of UPS batteries is influenced by temperature. High temperatures accelerate the degradation of battery components, such as the electrode materials and electrolyte, leading to a reduction in overall capacity. The elevated temperature also promotes corrosion and increases the rate of chemical reactions, thereby shortening the battery's life expectancy.

In contrast, low temperatures can also be detrimental. Cold temperatures increase the internal resistance of the battery, reducing its ability to deliver power effectively. The decreased efficiency can result in voltage drops and diminished capacity, ultimately shortening the battery's overall lifespan.


Best Practices for Temperature Management

To ensure optimal UPS battery performance and extend their operational life, it is imperative to implement effective temperature management strategies. Here are some best practices to consider:


  1. Temperature Monitoring and Control

Regularly monitoring and controlling the temperature surrounding UPS batteries is vital for maintaining their health. It’s important to consider intelligent charging, implementing a comprehensive temperature monitoring system or logger that provides real-time information on the battery environment. This allows for proactive measures to be taken, such as adjusting cooling systems or relocating the batteries if temperatures exceed the recommended thresholds.


  1. Adequate Ventilation and Airflow

Proper ventilation and airflow within the battery installation area are crucial for dissipating heat effectively. Ensure that the battery racks or cabinets are designed to allow sufficient airflow around the batteries, preventing heat build-up. Additionally, consider implementing cooling mechanisms such as air conditioning to maintain a suitable temperature range.


  1. Temperature Regulation through HVAC Systems

Leverage Heating, Ventilation, and Air Conditioning (HVAC) systems to regulate the ambient temperature in the battery room. Installing a dedicated HVAC system or integrating the battery room with the existing building's climate control infrastructure helps maintain a consistent temperature, safeguarding the UPS batteries from extreme heat or cold.


  1. Battery Placement and Spacing

When configuring the battery installation, ensure an appropriate spacing between individual battery units. Sufficient spacing allows for better airflow and heat dissipation between the batteries, preventing heat accumulation and potential hotspots. Follow the manufacturer's guidelines regarding recommended clearances to optimise temperature regulation.


  1. Regular Maintenance and Inspection

Implement a proactive maintenance schedule to regularly inspect and service the UPS batteries. This includes checking for any signs of corrosion, leakage, or damage caused by temperature fluctuations. Performing regular capacity tests and analysing battery performance data can provide valuable insights into their health and allow for timely replacements if necessary.


  1. Battery Replacement Considerations

Over time, UPS batteries will inevitably reach the end of their lifespan. When replacing batteries, consider selecting models specifically designed to withstand temperature variations and offer improved performance under different environmental conditions. The UPS supplier should be able to identify the most suitable options for your specific requirements.



Understanding the impact of temperature on UPS batteries is crucial for ensuring their optimal performance and longevity. By implementing effective temperature management strategies, such as monitoring, ventilation, HVAC systems, insulation, and regular maintenance, you can mitigate the negative effects of temperature on UPS batteries.

Power Control delivers comprehensive solutions that address the unique needs of their clients' critical power systems. By following the best practices outlined in this article, you can create an environment that supports the long-term reliability and efficiency of your UPS batteries. For further assistance or to explore our range of advanced UPS battery solutions, please contact us on 01246 431 431 or email

Remember, temperature control is just one aspect of maintaining healthy UPS batteries. It is essential to consider other factors, such as proper charging practices, load management, and battery chemistry, to ensure the overall robustness of your backup power system.


1 El Nino: What is it and how does it impact the weather closer to home?, Sky News, 17/05/2023