Battery Charger ?

[Pontoneer]

Forgive my awful description however I believe that you can connect a healthy battery to the completely flat battery, along with the charger, to kick start the charging process. Once it’s got some charge in it you can disconnect the additional battery and it will continue to charge.

I think the OP has now bought a CTEK MXS 5.0 so he should be able to revive very flat batteries with that - certainly I’ve managed it on pressure batteries which were drained completely flat and left for 6 months in a completely discharged state. That’s not good for the long term health of the battery though and it’s longevity will have taken a hit as a result.

Yes , you can do that , and it will work .

I was only commenting that the cheap Aldi/Lidl chargers , while they work well for their intended purpose , won’t charge a completely flat battery ; much as some automatic tyre inflators won’t inflate a completely flat tyre : they have to sense some pressure first .

Fortunately , as above , I have a couple of ‘dumb’ chargers that will charge any battery that is capable of holding a charge , from dead flat , and the three or four so called intelligent chargers that will maintain or recover batteries that have been allowed to stand a bit too long , with the proviso that sometimes batteries are beyond recovery if they have been neglected for too long .

 

[rf065]

It is clear that is how they work , so why would you assume it would start charging again when it is clear it won’t ? In any case , if your power goes out then unless you either have a UPS or a backup generator then no charger will be working . The point is that an unreliable electricity supply is not the fault of the charger .

Of course it doesn't work when the powers off, it's the fact that it starts to recharge when the power is back on. Not sure what point you're trying to make here?
More expensive chargers are designed to do this, cheap one are not.

 

[OneForTheRoad]

Of course it doesn't work when the powers off, it's the fact that it starts to recharge when the power is back on. Not sure what point you're trying to make here?
More expensive chargers are designed to do this, cheap one are not.

I'll test this theory in the morning using my £12 eBay special.

 

[Pontoneer]

Of course it doesn't work when the powers off, it's the fact that it starts to recharge when the power is back on. Not sure what point you're trying to make here?
More expensive chargers are designed to do this, cheap one are not.

My cheap Gunson charger will resume charging , as will my Crypton one , which in todays money , would cost a lot more than a CTEK .

On the other hand , my PAG chargers for my broadcast kit , which each run well into four figures , in the event of a power failure , need the charge mode selected individually for each of the four battery packs that can be connected before charging will resume .

Price has nothing to do with it .

The point about no charger working without electricity is that if your car has a low/flat battery then no charger will be of help to you if your power goes out .

 

[Bobby Dazzler]

Of course it doesn't work when the powers off, it's the fact that it starts to recharge when the power is back on. Not sure what point you're trying to make here?
More expensive chargers are designed to do this, cheap one are not.

I understand what you’re saying.

The more expensive maintainers tend to perform a test sequence every time they are connected to a battery and/or powered on, and will disable charging if charging conditions aren’t met,

They would do the same test following a power cut, so it will only resume charging if it is safe to do so. This is important in the event of a power cut as power will come back without anyone present.

Less expensive chargers tend not to have the capability of performing a test sequence and so will default to off (if risk averse or with soft buttons) or default to on (if not risk averse or physical buttons).

Personally I wouldn’t want to leave a battery on charge unattended if it can’t perform a test sequence, or doesn’t default to off, but we all have our own tolerance to risk.

 

[Chrishazle]

I can attest to the Lidl conditioner not liking a fairly flat battery, as that's what our s204 got to a while back and, as the Lidl was more accessible, I put that on the car first - and it would not play, so I had to get my SIP smartcharger out and that would start charging, but with only the first of the 4 lights flashing - so the battery was pretty flat! Had to leave it charging overnight and half the next day before it had done the full charge and turned itself of.

 

[alabbasi]

Ok, but they are built better than all the others, so I would disqualify all the others and get the Noco!

Noco doesnt stand by their products. I've had issues with their boosters after a handful of uses and they only offered is a 10% discount on a new one If I buy from their website. There are chargers with better features at a lower cost.

 

[C320]

Late to the party.
CTEK MXS 5.0. Lasted 5-years. Replaced under warranty. Second one is on Year 3.
NOCO advantage apparently is ‘force’ mode and that can charge a battery from zero volts.
Clearly they are missing a marketing trick: may the force be with you!