Performance of VRLA cells and monoblocs under arctic conditions

Stationary lead acid batteries of the VRLA-AGM design have been tested under Arctic temperature conditions so to evaluate their performance under quite abusive conditions. The results show that up to 56% of the room temperature capacity is available at -30°C and that repetitive and severe electrolyte freezing within the cells and monoblocs does not result in any functional degradation. "Frozen" electrolyte cells can be recharged. albeit with low current acceptance, even at -30°C and the presence of ice does not result in active mass spalling. The survival of monoblocs trapped in solid ice is also reported.