Battery Charger works but wont charge flat battery?

[Tampon]

I have a halfords battery charger, used it to keep a leisure battery topped up for a few years. I left the battery for a year or so and then the charger would not charge it. The test lights come up and say it is working just the two lights that say charging/ maintaining don;t light up.

I presumed I killed the battery by leaving it so long it won;t charge ( it was sealed )

I have now just taken the battery out of my bike, been standing for a few months and is dead so I decided to charge up ( had enough power in it to light the light but not turn the engine over a month ago ). Noticed the water was low so have tp it up with Distilled water and wacked it on the charger.

Now same thing is happening, charger switches on and make the noises but no lights on the charging/maintaining section. I have it on the right settings ( bike battery, not sealed )

I have just read here http://www.powerstream.com/how-to-use-a-battery-ch... that

"Also, if the battery is so low in voltage that the charger can't detect it, the charger won't turn on. In this case you need to bootstrap the battery by jumping it to another battery"

Does that mean if the battery is dead the charge won;t recognise it and won;t charge it ? seems silly to me.

If so what is the best option to do now ? jump start it off the car via jump leads and then leave the bike to run?

[bigdom]

Buy a new battery and also an optimate or equivalent for the future. It's really gone past the point of no return, it can be brought back to life, but it will be on borrowed time.

[playalistic]

Tampon said:

If so what is the best option to do now ? jump start it off the car via jump leads and then leave the bike to run?

Yep. Leave the bike running after jumping it or preferably go for a half hour run and then take it off to charge. Although I wouldn't hold much hope of this battery holding a charge for long now it has been nerfed.

[Tampon]

Borrowed time is fine, it is a £600 hack.

Do you have any idea about the charging, not charging thing ? Or how to get it to work ?

[Tampon]

playalistic said:

Yep. Leave the bike running after jumping it or preferably go for a half hour run and then take it off to charge. Although I wouldn't hold much hope of this battery holding a charge for long now it has been nerfed.

Cheers, going for a run isn't really possible as it is sorn no MoT, that why I am trying to fix it for the spring summer. So it will sit there for 1 hr just tick over

[RizzoTheRat]

Tampon said:

"Also, if the battery is so low in voltage that the charger can't detect it, the charger won't turn on. In this case you need to bootstrap the battery by jumping it to another battery"

Suggests to me you should be able to jump start the battery to get the charger working. ie connect the charger and jump leads to the battery, connect the other end of the jump leads to a good battery (your car), turn the charger on, disconnect the jump leads.

[Tampon]

Brillant, thankyou for that. If it doesn;t work I will try jump starting it and leave it running.

[LuS1fer]

They tend to die. We left a mobile phone for a year and the battery just refused to hold any charge thereafter.

[bigdom]

Tampon said:

Borrowed time is fine, it is a £600 hack.

Do you have any idea about the charging, not charging thing ? Or how to get it to work ?

Yep.

You've lost the deep cell charge, the acid would have bonded to the plates/eating them, which will be stopping the charge going across the cells due to sulfation.

As mentioned it may come back to life, would try a charger/conditioner like Optimate as they have worked miracles in the past. Now I just have them plugged in when left standing.

[Tampon]

Right I went to get the jump leads. Not happening. Not there. Bugger.



Got Heath Robinson about it and striped some cabling and made my own "jumpleads". Now hooked it up to the battery in the van for half and hour to see if it can put some voltage in the battery in that time then I will try it on the charger again.

If not the next move is to leave it hooked to the van battery and then hook up the charger in situ then try disconnecting the van battery to see if that works, but it is raining and I am running around in the rain with copper cabling hooked up to batterys with the wife on the phone on her lunch break asking me "are you sure?".

Yeahhhhhhhhhhhh it will be fine.

So do you think half and hour will be long enough to put some charge in the little bike battery just hooked up the big one ( engine not running obviously)?

[Tampon]

Right it worked a treat. Seem a small charge is what is needed in the battery for the charger to charge it. Seem to make a "battery charger" a redundant piece of kit if you need it most when the battery is flat !

[redgriff500]

There are chargers and chargers.

I once tried an Argos £25 jobbie - useless.

I now have a Sealey £300 one which will start a car with dead battery too - it works 99% of the time - it's outside trying to revive one now.

[Dogwatch]

To keep a battery charged during long periods of non-use you need a battery conditioner, not a trickle charger. The trickle charger pumps a charge into the battery whether it needs it or not whereas the more expensive battery conditioner detects that the battery has lost some charge and tops it up.

[mad4amanda]

Its actually a newish safety feature apparently, I had the same issue and used a pp3 9v battery to fool the charger. it stops the charger if it doesnt sense a voltage

[Tampon]

£300 !!!!!

I will stick to my secondhand £10 jobbie and a bit of lateral thinking. That like 20 lapdances, 30 if you go at lunchtime

This one seem to "maintain", flicks between maintain and charging during the day, and if you switch it to bike setting it trickle charges a car battery as well.

[Digger]

For a reasonably priced conditioner i can recommend one of these.

http://www.amazon.co.uk/Ctek-CTE-XS3600-Battery-Ch...

[murphybob]

I know this is an old thread but it helped me so I thought I'd add some extra information. I read this but didn't have a good battery on hand to hook up in parallel to trick the battery charger into doing its stuff.

After a bit of head scratching I wondered if the threshold for voltage to trick the charger was near 12v or if it just needed a few volts above zero. I stripped the end off an old Nokia 6v phone charger from the ubiquitous 'cupboard of old phone crap' and hooked it up across the battery terminals along with the charger. Much to my surprise the charger started charging

I was a bit worried that something might blow up so after a minute I tested removing the phone charger and the battery continued to charge with just the charger.

For reference it's a cheapo Halfords charger, and the battery was completely flat (I tested ~0v). It's now fully charged and giving ~11v. I've no illusions that it won't last long and I wouldn't go far on it, but it'll get me to the MOT center and they can jump me if needs be to get home.

Anyway I thought I'd post this in case it helps someone who is in a similar situation.

Cheers,
Rob

[scubascuba3]

I like the idea of the last post. Does anyone know what the black red white green wires are in the USB cable and how should they be connected to the +ve and -ve of the battery?

[scubascuba3]

Interestingly wiki says the following:

The standard USB A plug (left) and B plug (right)
Pin 1 VCC (+5 V, red wire)
Pin 2 Data− (white wire)
Pin 3 Data+ (green wire)
Pin 4 Ground (black wire)
USB - Wikipedia, the free encyclopedia

So does this mean I can just connect black to black and red to red and ignore the other two wires?

[TooMany2cvs]

Tampon said:

Right it worked a treat. Seem a small charge is what is needed in the battery for the charger to charge it. Seem to make a "battery charger" a redundant piece of kit if you need it most when the battery is flat !

Problem is that a smart charger needs to "know" it's got the right type of battery attached before it'll start to charge, and it'll adjust the charging voltage/current to best charge the battery. If the battery's so flat that the charger doesn't "see" it, it won't charge it.

So you need a dumb charger that just blindly shoves out +14v whatever. Then make sure you don't leave it on for an extended period, because it WILL bugger the battery up...