What can happen to sealed batteries

We’ve longed for  AGMs or some cheaper sealed batteries quite a lot. But their price and charging requirements finally discouraged us and we opted for 6 volt Trojans T-105. Surely it does not happen everyday and the probability of something like this is perhaps lower than that of spilled electrolyte. On the other hand, on a boat in the middle of nowhere, one could likely handle the electrolyte better than a gel bomb…

Expanded sealed battery

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