Saving a "dead" battery

Norman_E

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I am posting this in the hopes it helps someone.

I have two garden tractors, one of which is old and only used for rough work. Over the winter I forgot to charge its battery, (which is a small car battery) and found it dead, such that all it gave was enough power to click the starter solenoid. I put an ordinary Halfords battery charger on it and left it for two days, after which it had not taken any charge.

I was about to buy a new battery when I remembered that I have a Lidl battery charger with three settings, for motorcycle batteries, car batteries and one marked with a frost symbol. The latter is I think designed to revive dead batteries, though I have lost the instructions. I connected it and left it for a day, turned it off last night as it showed a light indicating that the battery was charged. After leaving it overnight I tried the starter, and it cranked the motor very well, and it started after a few attempts. It looks as if the Lidl charger actually can revive a battery that has dropped way below 11 volts.
 
Like you I also got a LIDLE battery charger. I have just replaced my car battery as it was the original battery 16 years old... I REPEAT 16 YEARS OLD !!!! and it is stil OK. well I left it and forgot about. Then I thought that I would test it DEAD it was FLAT. The LIDLE charger revived it so it is on the boat as a back up cranking batt.

Peter
 
I am posting this in the hopes it helps someone.

I have two garden tractors, one of which is old and only used for rough work. Over the winter I forgot to charge its battery, (which is a small car battery) and found it dead, such that all it gave was enough power to click the starter solenoid. I put an ordinary Halfords battery charger on it and left it for two days, after which it had not taken any charge.

I was about to buy a new battery when I remembered that I have a Lidl battery charger with three settings, for motorcycle batteries, car batteries and one marked with a frost symbol. The latter is I think designed to revive dead batteries, though I have lost the instructions. I connected it and left it for a day, turned it off last night as it showed a light indicating that the battery was charged. After leaving it overnight I tried the starter, and it cranked the motor very well, and it started after a few attempts. It looks as if the Lidl charger actually can revive a battery that has dropped way below 11 volts.

Good to know that the Lidl charger does what it is claimed for it.

The Ring Smartchargers have been reported on here as reviving "dead" batteries too. They are available in range of sizes up to 16 amps as well as a small one comparable with the Lidl ones.

BTW the instructions for the Lidl charger are available on line .... somewhere .. but sorry I dont have a link.
IIRC Google will find them if you search for the brand name on the charger
 
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This sounds amazing to me,does it mean that you can resurrect old batteries that have been dormant in a boat for years?How do you tell if a battery really is beyond hope? & finally how much does this wonder machine cost?
Yours in anticipation :)
 
This sounds amazing to me,does it mean that you can resurrect old batteries that have been dormant in a boat for years?How do you tell if a battery really is beyond hope? & finally how much does this wonder machine cost?
Yours in anticipation :)
No they are not wonder machines.

They will recharge deeply discharged batteries when other automatic chargers sometimes won't.

I've not tried mine on a deeply discharged battery but when I first got it it automatically went into recondition mode on one of my car batteries.

The history behind me buying mine was that I'd often thought of buying a modern charger .... I think the one I was using was left behind by the Romans.
Someone on the forums asked for advice on what to do with a battery that had been deeply discharged and that he could not recharge. I suggested he looked at the Ring Smartchargers because Ring claimed they would recover a deeply discharged battery.

A little while later he reported that he had bought one and that it had successfully recharged his battery.

Sometime after that I noticed a Ring Smartcharger in Halfords. I bought it.
I did not know at the time that there was a range with different outputs but I would have chosen the 8 amp one that I had bought any way.

I could have shopped around and saved money but i was in the shop and it sort of said, "buy me."

More recently Ring have launched a Smartcharge + range. I beleive one of those was voted "best buy" by one of the magazines.

None of them would be suitable for permanent installation IMHO. They draw a small but significant current from the battery when not powered up.
If the power is disconnected they default to they lowest output setting when repowered.

Halfords currently have the 12 amp version of the Smartcharge + on their website
http://www.halfords.com/webapp/wcs/..._productId_821951_langId_-1_categoryId_255205

From time to time Lidl have their little one on offer
Aldi often offer something similar
 
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No they are not wonder machines.

They will recharge deeply discharged batteries when other automatic chargers sometimes won't.

I've not tried mine on a deeply discharged battery but when I first got it it automatically went into recondition mode on one of my car batteries.

The history behind me buying mine was that I'd often thought of buying a modern charger .... I think the one I was using was left behind by the Romans.
Someone on the forums asked for advice on what to do with a battery that had been deeply discharged and that he could not recharge. I suggested he looked at the Ring Smartchargers because Ring claimed they would recover a deeply discharged battery.

A little while later he reported that he had bought one and that it had successfully recharged his battery.

Sometime after that I noticed a Ring Smartcharger in Halfords. I bought it.
I did not know at the time that there was a range with different outputs but I would have chosen the 8 amp one that I had bought any way.

I could have shopped around and saved money but i was in the shop and it sort of said, "buy me."

More recently Ring have launched a Smartcharge + range. I beleive one of those was voted "best buy" by one of the magazines.

None of them would be suitable for permanent installation IMHO. They draw a small but significant current from the battery when powered up.
If the power is disconnected they default to they lowest output setting when repowered.

Halfords currently have the 12 amp version of the Smartcharge + on their website
http://www.halfords.com/webapp/wcs/..._productId_821951_langId_-1_categoryId_255205

From time to time Lidl have their little one on offer
Aldi often offer something similar

OK Vic that's interesting though complicated.How do you know if a battery is absolutely screwed,do you test the acid content or something,is it the plates that buckle or can you flush them out & remove sediment that blocks the plates as I believe my old man used to do as a car mechanic 70/80 years ago.How do you know when they are absolutely irredeemable?
 
The short answer to knowing if a battery is dead or merely sleeping is to suck it and see. My alternator diodes died and discharged both batteries (domestic via the split charge relay) to about 3v. One came back as good as new, the other stayed dead.

Yes, I know I should have isolated the batteries when I left the boat, but it's a bit of a faff and I got lazy. :rolleyes:
 
How do you know when they are absolutely irredeemable?

When you cant recharge them to a fully charged hydrometer reading or a satisfactory rested open circuit voltage reading.

When they wont hold the charge.

when they fail a "drop test" or simply wont crank the engine properly.

How do you decide when to replace your car battery ?
 
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When you cant recharge them to a fully charged hydrometer reading or a satisfactory rested open circuit voltage reading.

When they wont hold the charge.

when they fail a "drop test" or simply wont crank the engine properly.

How do you decide when to replace your car battery ?

Can't remember it was so long ago but the one I can remember replacing was I expect older than God's dog .The boat I am buying has two what looks like very good condition expensive marine batteries in it but the owner reckons they are knackered.He tried charging them up with a very expensive looking brand new BMW car type charger.
I am very tempted by this Lidl charger judging by what you lot have said & am reluctant to give up on them just yet.My neighbour mentioned in a chat over the garden fence just now that he added Aspirins to his battery & it rejuvenated it! :eek:
 
When you cant recharge them to a fully charged hydrometer reading or a satisfactory rested open circuit voltage reading.

When they wont hold the charge.

when they fail a "drop test" or simply wont crank the engine properly.

How do you decide when to replace your car battery ?
A 'drop test' isn't the best test for the domestic batteries on a boat for various reasons.

A much better test would be a capacity test using a know load (say a car headlamp) over a period of hours. You monitor voltage and specific gravity and find out what the Ah capacity of the battery is at the discharge rate you have selected. Drop tests only measure the voltage drop at cranking type currents which is inappropriate for a domestic battery and could conceivably damage some batteries.
 
You used to be able to buy "BatAids". These were small tablets of some chemical that you dropped into each cell of a dead battery and then recharged. I used them a few times on Lawnmower and Motorbike batteries that were dead as a Dodo. Maybe they would help your garden tractor batteries retina charge better.
 
You used to be able to buy "BatAids". These were small tablets of some chemical that you dropped into each cell of a dead battery and then recharged. I used them a few times on Lawnmower and Motorbike batteries that were dead as a Dodo. Maybe they would help your garden tractor batteries retina charge better.
Every time I have tried them, I wish I'd saved my money and put it towards a new battery... From what you say they work for some people, but they have never worked for me.
 
The idea is they put in higher voltage spikes into the battery which breaks away the sulphur on the plates, reviving a sulphated dead battery, normal chargers cant break off the sulphur as the voltages are too low
 
flat battery

good afternoon!
have read with interest the tread and on the end i have the same problem - flat battery :(
it is sealed one "delphi" 105 ah
the charger is bosch with option for low/high and 6v/12 v
i put in position 12 V and first was on high and now is on low
the charger work about 30 sec on very high voltage , above 12 v with some strange noise and
after drop to 0 (zero) for a few minutes and again repeat the cycle
on the high voltage the battery show - 8.9 V
once the charge show 0 (zero) the battery is 7.2 V
is this normal or it is much better to stop the efforts and buy a new battery before to damage the charger?
thanks and brgds
 
Batteries are so cheap, and such a vital item when you are out at sea, that I suggest you just buy new ones. I do use older batteries on my caravan, but it is on a site with 240 volt so not a worry!!
 
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