Discussion
A phenomenon, as after a failure, you are only buying time. Just replace with a battery ‘one up’ the range, avoid the cheapest of the cheap. This is for ‘normal’ cars, sadly different if you are unlucky enough to have the gimmick of stop-start.(TVR won’t have that , new BMW often has 2 batteries - as bad as a boat!
Edited by Lester H on Wednesday 3rd February 09:20
Not so much a modern phenomenon, more a lead-acid phenomenon.
When a battery goes completely flat, a chemical reaction takes place much quicker than when it is charged. This is 'sulphation' and it is a coating which is deposited on the lead plates causing it initially to reduce the capacity, or if left, killing the battery altogether. It is pretty much irreversible, although I have, back in the 70s, used a product called BatAid to some effect.
Anything more than about 3-4 days in a flat state will be the start of the death-knell for most batteries.
When a battery goes completely flat, a chemical reaction takes place much quicker than when it is charged. This is 'sulphation' and it is a coating which is deposited on the lead plates causing it initially to reduce the capacity, or if left, killing the battery altogether. It is pretty much irreversible, although I have, back in the 70s, used a product called BatAid to some effect.
Anything more than about 3-4 days in a flat state will be the start of the death-knell for most batteries.
littleredrooster said:
Not so much a modern phenomenon, more a lead-acid phenomenon.
When a battery goes completely flat, a chemical reaction takes place much quicker than when it is charged. This is 'sulphation' and it is a coating which is deposited on the lead plates causing it initially to reduce the capacity, or if left, killing the battery altogether. It is pretty much irreversible, although I have, back in the 70s, used a product called BatAid to some effect.
Anything more than about 3-4 days in a flat state will be the start of the death-knell for most batteries.
This is correct.When a battery goes completely flat, a chemical reaction takes place much quicker than when it is charged. This is 'sulphation' and it is a coating which is deposited on the lead plates causing it initially to reduce the capacity, or if left, killing the battery altogether. It is pretty much irreversible, although I have, back in the 70s, used a product called BatAid to some effect.
Anything more than about 3-4 days in a flat state will be the start of the death-knell for most batteries.
Once you have discharged around 80% ish capacity from a lead acid battery you start to cause damage which affects its ability to take and hold a full charge.
col711 said:
It may be possible to revive the battery depending on how old it is and how 'flat' it is. I have a CTEK battery charge that claims to revivie not completely flat batteries. I think 2% charge must remain for it to work. You could seek to borrow a similar automatic charger to try it.
One of my cars I ignored this year thanks to Covid, it was sitting in an unpowered garage, sorn it, and was out of sight, out of mind. Last time I drove it was March for a work conference in the countryside just before the first lockdown, and I had to give it a good charge then to get it to fire up. Come Autumn, to get it out to give it a wash, the 2 year old battery read 3v. I stuck it on my older Ctek, and took maybe 5 days to bring the bring 100Ah battery to 'green'. It started the car, a big V8, but couldn't do it a few hours later in cold temperatures as it simply didn't hold it's charge.I investigated getting a Ctek MXS 5.0 with the revive function, but watching some in-depth analysis from Electrical Engineers, my conclusion was it doesn't to squat to revive a battery with dead cells, so not worth buying for that reason. The second was the MSX 5.0 charger has (design) issues, runs way too hot, and significant people reported them dying.
I did recently buy a XS 0.8 as one of my bikes that has to have an alarm so will kill a battery if I don't keep on top of it, so bought a second charger so I can just leave it connected. The rest of the bikes without alarms just need a top up mid winter to keep them good. So I have 2 Ctek chargers (and might buy another XS 0.8, since if I get another year from the bike batteries it pays for itself), I can't remember when I bought my 3.6 as it was that long ago, it has been used constantly over the years, and never done me wrong, but Ctek's are a bit over hyped IMHO.
smack said:
One of my cars I ignored this year thanks to Covid, it was sitting in an unpowered garage, sorn it, and was out of sight, out of mind. Last time I drove it was March for a work conference in the countryside just before the first lockdown, and I had to give it a good charge then to get it to fire up. Come Autumn, to get it out to give it a wash, the 2 year old battery read 3v. I stuck it on my older Ctek, and took maybe 5 days to bring the bring 100Ah battery to 'green'. It started the car, a big V8, but couldn't do it a few hours later in cold temperatures as it simply didn't hold it's charge.
I investigated getting a Ctek MXS 5.0 with the revive function, but watching some in-depth analysis from Electrical Engineers, my conclusion was it doesn't to squat to revive a battery with dead cells, so not worth buying for that reason. The second was the MSX 5.0 charger has (design) issues, runs way too hot, and significant people reported them dying.
I did recently buy a XS 0.8 as one of my bikes that has to have an alarm so will kill a battery if I don't keep on top of it, so bought a second charger so I can just leave it connected. The rest of the bikes without alarms just need a top up mid winter to keep them good. So I have 2 Ctek chargers (and might buy another XS 0.8, since if I get another year from the bike batteries it pays for itself), I can't remember when I bought my 3.6 as it was that long ago, it has been used constantly over the years, and never done me wrong, but Ctek's are a bit over hyped IMHO.
Did you really think anything can revive a battery with dead cells?I investigated getting a Ctek MXS 5.0 with the revive function, but watching some in-depth analysis from Electrical Engineers, my conclusion was it doesn't to squat to revive a battery with dead cells, so not worth buying for that reason. The second was the MSX 5.0 charger has (design) issues, runs way too hot, and significant people reported them dying.
I did recently buy a XS 0.8 as one of my bikes that has to have an alarm so will kill a battery if I don't keep on top of it, so bought a second charger so I can just leave it connected. The rest of the bikes without alarms just need a top up mid winter to keep them good. So I have 2 Ctek chargers (and might buy another XS 0.8, since if I get another year from the bike batteries it pays for itself), I can't remember when I bought my 3.6 as it was that long ago, it has been used constantly over the years, and never done me wrong, but Ctek's are a bit over hyped IMHO.
They only way to revive them would be to replace the cell
Chris32345 said:
Did you really think anything can revive a battery with dead cells?
They only way to revive them would be to replace the cell
I didn't know at the time, the battery had only gone flat once before, not totally flat, just not enough juice in to crack over the engine. It was only after trying to bring the 2 year old Silver Yuasa battery from the dead did this become clear. My fault, and cost me a new battery. All the recon mode does is charges the battery for a period with around 15v, it produces marginal improvement when tested.They only way to revive them would be to replace the cell
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