Jump leads alternative

forgotmyname

If its left flat in a discharged state, that is what ruins them. The cells start to sulfate and lose their capacity to store energy.

OP rather than waste money on a jump pack, why not sort the issue of why the battery went flat.
A run into town should have charged it more than what you took out to start it in the first place.

Get yourself a battery charger and give it a boost once a month. That will help the battery live much longer.

Dont buy a cheap booster pack. I have the machine mart one and its brilliant. Battery still good after 8 years. I think its time to think about replacing it though.

Dont forget the jump pack will need charging monthly even if you dont use it.

My sister bought one instead of replacing the cars battery. She ended up with a dead battery and a dead jump pack.

Strider590

Joe_Horner wrote: »

If a lead acid battery is allowed to stay flat for an extended period it'll suffer sulphation of the plate

Sulfation happens at any time that the battery is not at 100% charge, the amount depends on how discharged it is.


Edit - I should point out that a battery is never 100% charged, it's just not possible. Otherwise they could be sat on a shelf for 20 years and still be perfectly ok to use.

Joe_Horner

Strider590 wrote: »

Sulfation happens at any time that the battery is not at 100% charge, the amount depends on how discharged it is.


Edit - I should point out that a battery is never 100% charged, it's just not possible. Otherwise they could be sat on a shelf for 20 years and still be perfectly ok to use.

Formation of lead sulphate doesn't "happen any time the battery's not at 100% charge", it IS the chemical process by which the battery discharges. It's also reversible by charging.

"Sulphation" as a problem occurs when the soft, easily re-converted,amorphous lead sulphate produced during discharge crystallises and "hardens" on the plates. That only happens over time - whether over normal cycles or being left standing, it's time that allows the sulphate to crystallise. So having the battery discharged for (say) a few days doesn't make it suddenly a problem any more than those few days would be in normal use.

The fact you can't store a battery indefinitely also isn't anything to do with "never charging 100%. Of course you can charge a battery 100% because 100% simply means "the most charge it can hold" so, by definition, when you can't raise its charge anymore, it's 100% charged.

Storage problems are caused by the self-discharge rate, which for lead acid is typically around 15% per month. That means that, absent any load or charging, some of the lead will be forming sulphate and (eventually) crystallising all on its own.

Hence the "recharge by" dates on new batteries - usually 2 years from manufacture. That's the date when a seller should recharge them by if they haven't been sold and gone into service yet.

By that time the battery will have lost 25% of its original charge and will have spent over a year at under 85%. Yet it will still be fine to sell "as new", with "as new" capacity, even having sat partially discharged all that time.

IamNotAllowedToUseMyName

Ranger8 wrote: »

If the battery is a few years old and has had a bit of a hard life (short journeys) better off investing in a new battery.

It all depends. We were not using the 52 reg Golf and then daughter borrowed it to park for weeks on end at uni without driving it. The battery flattens in about 4 weeks due to the immobiliser.

It has been jump started a dozen of times over the last couple of years due to having gone flat. Had the battery tested when was convinced it must be trashed, and it was reading fine.

So although it might not be the best thing for the battery, it is not a given that a battery will be ruined by going flat. Over the years I've flattened loads of batteries and they have always recovered with a drive and not been a noticeable problem afterwards.

Whether I have shorted their life, I don't know, but my money saving tip is "If it works, don't fix it!"

To make life easy for daughter I spent about £50 on an RAC starter pack. Easy to use, keep it charged up every couple of months and it meant that daughter could get home at the end of term - saved me 400 miles of petrol every term.

Strider590

Joe_Horner wrote: »

blah blah etc etc

Once charged fully, a lead acid battery should be left no longer than 6 months. Slightly more for an SLA.
Removing sulfation requires a specific charging method, namely low current pulsing at higher than normal voltage.

Plenty of information on line, so this is really just a waste of my time.


Oh and I use the American spelling "sulfation" because it's easier to Google and yields more search results.... FYI

Quentin

Strider590 wrote: »

If a car battery is allowed to become flat, it is ruined.......

As you profess to use google, why not google this topic?


(According to you, everyone who leaves their lights on by mistake and flattens their battery needs to go and buy a new one)

Strider590

Quentin wrote: »

As you profess to use google, why not google this topic?


(According to you, everyone who leaves their lights on by mistake and flattens their battery needs to go and buy a new one)

No, they've just reduced its useful life considerably........ Ruined a perfectly good battery.

If your cell phones battery only lasted half as long as it did when new, then you'd either get a new one OR get a new phone.

Yet when a car battery loses half it's capacity, it's still perfectly ok?

With phones we all think we're experts, because a real expert made it easy for simpletons to us one. But with cars, people still fear them as being too complex (yet ironically play them down as being simple things for dirty lower class men in overalls to work on).

OddballJamie

Surely if that was the case, by now the AA would've jumped on it and forced a new battery on everyone, rather than just charging/jumping their current one.

Strider590

OddballJamie wrote: »

Surely if that was the case, by now the AA would've jumped on it and forced a new battery on everyone, rather than just charging/jumping their current one.

Telling a customer they need something that they think they don't?
Yeah good luck with that :rotfl:

OddballJamie

Strider590 wrote: »

Telling a customer they need something that they think they don't?
Yeah good luck with that :rotfl:

If it was a money spinner for them, then why not?

Millions of people everyday buy things they don't need but feel compelled to buy.