Saturday, Jun 01, 2019 at 12:55
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Yes Frank, the technique maybe had some validity back with the old vented batteries as it could be theorised at least, that creating a spark close above the battery could ignite any cloud of hydrogen present. The likelihood in my mind was minimal to zilch. Not much hydrogen would be vented and any that was would rapidly dissipate. I never experienced it except once (see below).
And in the case of current sealed batteries, the possibility would be less-than-zero.
I referenced that method of attaching jumper leads because it has become universally accepted and I didn't want to ignite the usual flaming. (
forum verbal, not hydrogen. lol)
In point of fact, I always attach the negative clamp directly to the battery post. I am seeking the best possible connection to both batteries.
However, it is one thing to have electrical understanding and experience and quite another to have absolute belief, usually gained from some bloke at the pub.
The exception I referred to above was long ago at
Woomera Range where we had a whole bank of batteries in series on charge, gassing away madly with their caps sitting loosely on top, and due to mal-operation of the charger, I caused a spark at one of the jumper clips. There was an almighty flash and roar and all the caps were projected into the roof. Didn't do the charger much good either!
I have also had a battery "explode" due to an intermittent internal connection break. So it can happen. But I think not to sealed batteries, especially in open air. And if it did, would probably only harm your eyebrows.... and maybe your underpants.
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