Compact-Power™ cells and monoblocs can be operated from -30 °C to +40 °C. At low temperatures charge acceptance and capacity decreases. At high temperatures premature aging and dangers, in connection with other factors, of thermal runaway exist.

Compact-Power™ cells and monoblocs achieve their design life of up to 15  years float service at the European Standard Stationary Battery reference temperature of +20 °C (+68 °F). An operating temperature above this value shortens the service life accordingly. Theoretical considerations and practical experience has shown that every 10°C temperature rise above the 20 °C reference temperature halves the service life. The service life is thus 100% at 20 °C, 75 % at 25 °C, 50 % at 30 °C and 25 % at 40 °C.

At temperatures below the reference value of 20 °C an increase of service life can be expected. However under this condition reduced capacity (-0.6 to -1% per °C) and reduced charge acceptance occurs.

The high temperature life reduction factor is widely employed by battery manufacturer to test in an accelerated way the VRLA battery designs. In these life tests a test temperature of 55 °C, 60 °C or 80 °C is widely employed. Oerlikon Stationary Batteries Ltd. uses 60 °C with 2.28Vpc float. Under these conditions a Compact-Power™ cell or monobloc service life of >45 weeks to 80 % of rated capacity, when monitored with 10 minute high rate discharges, is routinely obtained. This amounts to a 20 °C service life of >14 years. See also the US Bellcore publication Technical Reference TR-NWT-001200,1,1992 "Generic requirements for accelerated life testing of valve regulated lead acid batteries at high temperatures".

For the battery installation planner and operator following points are of interest:

• Reduce energy input into the battery by adjusting the float voltage according to the Compact-Power™ operating instructions.
• Provide adequate ventilation and, if necessary and economically viable, cooling.
• Protect battery against radiant heat and warm exhaust air.
• Assure in multitier battery installations a homogeneous temperature within the battery string
  (T of <3 °C)
• Avoid excessive AC currents in the battery circuits. They cause Joule heating of the battery and can cause extremely rapid battery aging. If needed install DC line filters.

Oerlikon Stationary Batteries Ltd. furnishes self-adhesive LC temperature strips to be attached to the walls of suitable and representatively positioned cells and monoblocs in a battery. These Kelvin-Arrhenius Monitors™ give, like a speedometer, the actual service life expectancy in percent of the +20 °C (+68 °F) life based on the 10 °C/half life rule.