I called at my brothers today, he answered the door, and I was shocked to see the state of his face.
His top lip was split, his chin badly bruised, he looked for all the world like a baseball bat victim.
I asked him what happened, it turned out he had a 110amp battery on charge and had gone to
disconnect it a spark from the disconnected terminal had set off the hydrogen, the battery exploded ,
the top hit him in the face and knocked him on his back. There were jagged plastic shards everywhere,
some stuck in the insulation boards. He was very lucky, not to have received worse injuries and a face full of acid.

He was extremely lucky, and it could happen to anyone! Hope he is ok and not to battered by his experience

Had the same thing happen to me many years ago but no serious injuries I'm pleased to say. My own stupid fault really as one should always pull the plug first followed by pulling the positive lead.

And you'd be right to differ 'old fruit'. Brevity leads to mistakes and I should have said; remove charger from mains then remove negative cable first and install it last.

very lucky indeed, they go off super quick and loud
always wear protective gear including full face shield and gloves, to save sight, nose job, and skin grafts
fitted a battery box in eriba for this reason and sometimes battery cases split, acid or battery gunk is hard to clear up when inside.
Hope brother recovers quickly

He was very lucky Rod, I remember when I was in my garage cleaning my old MGB battery terminals which are twin 6 volts located behind the rear seats. I used a big bit of wire wool which unfortunately touched both terminals and it went up like a Roman candle. The wire wool dropped through the void in the battery box and then set fire to the underseal on the petrol tank. I fell out of the car onto the floor I and managed to use a rag to put the fire out. It could have been a very different story.

Wire wool and a pp3 battery is a good way to start a fire, used it a lit in the past. Don't want to deteriorate the seriousness of this thread though

deeps were you thinking of positive earth?
i know some tractors were wired this way, and some makes of older cars
they changed to positive positive because they realised the positive earth was speeding up body corrosion.