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Flat jumpstart battery

Yes I know it seems like a joke but my jumpstart battery is really totally flat, I suspect when putting it away I accidentally clicked the light switch on.

When trying to recharge it with its supplied charger, it emitts a buzzing noise and will not charge. I then took out the internal battery and tried to charge it with my super-duper charger; this didn't want to know, probably because the voltage was only 9.5 and so didn't register on the automatic gubbins.

I then went to Lidls as mentioned in a previous thread and bought an identical one for £20 with a three year guarantee ( mine was just out of it's one year warranty )

The question is, is there any way I can browbeat this sealed battery into life again or shall I just throw it away.

Reply to
Steptoe
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Depends on the capacity but I'd give it the Lidl charger until it starts to take some current, as soon as it does put it back in the jumpstarter and charege it normally.

The problem comes from totally flattening the battery, on the sealed cell ones this means that the electrolye is almost pure water as all the free acid has gone, and hence it won't take much current at all. If it takes some current then it should eventually start charging, but it can take days.

Reply to
Chris Street

You could just buy a new sealed battery. Or stick 18V across it for a bit

Reply to
Duncanwood

At the moment I have the Lidls Jumpstart and the old one linked and charging through the Lidls. As yet no charge has been taken by the old one, though from Chris's post it seems that this might take some time.

As regards Duncan's suggestion of purchasing a new battery, I'd thought of this but suspect that the price may well be greater that £19.99! However the Lidls and the old one are identical apart from the branding and the Lidls has a 'genuine' fault in that the charging LED doesn't illuminate, (though it does in fact charge)......hmmm......

Reply to
Steptoe

look on

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for sealed lead acids. You want a deep cycle gel one probably.

Reply to
Chris Street

You can get deep cycle gel batterys from motorcycle suppliers or electric vehicle suppliers. CPC's probably chepaer though

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. If the old ones not been flat for too long then 100mA at 24V will recover it.

Reply to
Duncanwood

You ever managed to blow one of those up by incautious charging? I thought I'd been shelled when it finally let go - I'd not selected current limit on the bench supply.....

Reply to
Chris Street

Not made that mistake .... yet :-)

Reply to
Duncanwood

Just as a postscript to this saga, I put it on charge on 24v, monitoring the voltage, interestingly enough the charger must have sussed out the situation as it only put about 18v out. Unfortunately the battery output fell steadily despite doing this, ending up at about 8.5v.

I finally gave up, put the still immaculate jumpstart ( 1 year & 2 weeks old ) in it's original immaculate packaging with the instruction manual and took it down the local auction. It made £21!!!!!

bearing in mind it cost £25 new & I had just bought the same model from Lidls for £19.99 with a three year warranty, what have I been messing about for?

Reply to
Steptoe

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