Battery charging

OneThinBloke

OneThinBloke

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Location
Oxfordshire, UK
I have been an idiot!

After using my Atlas’ engine to help me load him on my trailer yesterday morning, I managed to leave the ignition switched on… Predictably the battery is now empty!

Is there and reason why I can’t charge it up by connecting to the battery of my Land Rover for the next leg of my journey to Italia?

Tia
 
I think it’s a good idea. Although I wouldn’t leave it too long, normally it’s important that when charging two batteries from the same charger that they are a similar capacity. However the little bike battery will charge a bit just by being connected, without starting the Land Rover.
Although it has to be said, running any lead battery dead flat will severely reduce its capacity and lifespan.
 
If it is dead flat zero volts, a trickle charger won't register it, and won't start charging it. Connecting it to another battery for a while will bring it up so that a trickle charger will work.
 
I had the same thing being dim and all, leaving the ignition on like you overnight..

The remedy is to get a decent size fully charged 12v battery and with jump leads connect it positive to positive,negative to negative and leave it like that for half an hour....

Check that your flat battery doersn't get hot or swell, if it doesn't it's knackered...after half an hour connect the smart charger with the batteries still connected together, charge for half an hour, leaving the charger still connected then disconnect the supplementary battery and charge as normal till fully charged...

Your AGM battery is back to life as normal😉👍👍
 
I have a 3-way gauge to fit to my Atlas, it shows Volts, Ambient Temperature and the time. But sadly not ignition on. That's the NutraLights' job. It takes some time to access Atlas batteries and even more time on mine with its panner racks needing to come off as well, so I have a remote battery charging piggy back lead poking out for easy acces. That makes jumper lead attachment tricky; I have to look into that. I did manage to find the biggest battery I could that fits. Thankfully, cutting massive holes into the rear mudguard to get a stupidly even bigger battery fitted is now a forgotten nightmare.
 
On an AGM battery once completely flat, a smart charger won't charge it unless it's done the way I've mentioned....it worked for me and I got the fix on good authority from Tayna Batteries in N Wales...mine was a brand new one so was doubly glad it worked
 
Hi.
I'm assuming you have a suitable charger. If not, you're welcome to bring it over. I have a bike type agm specific charger with recovery mode and a Victron agm charger.

As a point of interest, a proper agm type charger has a separate charging profile 14.6-8 volts which will fully charge an agm battery 100%

A lead acid battery requires 13.8- 14.4volts and although chargers are often marketed as suitable for agm even with 7 stage charging, they have this defecit and will only charge agm to 85%.

Edit: seems I misunderstood, you're already on your way. If you have an alternator on your landrover, you'll get 14.4 volts and charging, not so great with a dynamo but some success if 13.5 or above.

Rob
 
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Not all cells will be in deficit at the same SG ( specific gravity ), if you attempt a recoup of charge/ah rate on a sub 11V discharge, in order to attempt a best recovery, an "equalise" voltage at some 16V or slightly more, for a shortish period, dependant on battery size and chemistry is required. Mentioned this prior here.

Not aligned to some of the techniques mentioned above, worst if unlucky a fully charged battery connected to a well depleted battery may lead to unexpected outcome(s), including gassing and explosion in certain if not rare unfortunate combinations. HTH j.
 
Thank you all for your replies. I have a small selection of basic tools with me, including a multimeter.

I have connected the Motobatt to the Landy’s battery via jump leads without running the engine. I have measured the current flow (charging rate?) at approximately 2.6 amps.

I will monitor carefully over the next hour or so, and revisit in the morning.

A more challenging hitch has arisen that definitely stops my onward journey before Monday!
Landy tow hitch has become somewhat un-hitched…
2 M12 LHS fixing bolts un-fixed themselves and are now littering the carriage way or verges of somewhere in north eastern France.
I tried but failed to score some bolts today, v. little chance of greater success Sunday!
And, to be honest, I will be needing help to refit the hitch. Its f**cking heavy.
Yes, I was the twat who it would appear inadequately fitted it in the first place.

James
 

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It's not recommended that you leave the Landy battery connected for over three quarters of an hour...it might damage your motobatt...so get it on charge following the method I used asap..

It's for you to make up your own mind as to what to do, I'm not wanting any comeback
 
Lucky you didn't lose the whole trailer!! If the M12 holes are open you could temporarily fit M10 bolts and nuts (if they're more readily available).
 
The things you find, a while back I discovered the pin that allows my trailer hitch to be removed without tools from my car, it's massive, probably also 12mm thick had almost rusted in 2. It had a countersunk bevel completely gone from full thickness to appox a 3mm sliver remaining all hidden from easy view. I just happened to wonder how easy it would be to remove, and that pin nearly came out in 2 bits. One on each side. What I don't understand is that it looks Galvanised. Nothing around it has rusted,
 
Update:-

Correction of earlier information. Missing bolts where an M10 through bolt and a M12 bolt into a blind hole.
Unbelievably I have found the M12 bolt in the trailer! However, despite sourcing some M10 bolts yesterday and finding the M12 today, I will still seek assistance tomorrow to refit the hitch.
Repairing the damaged wiring was an easy fix, I have selection of double crimp connectors, insulation and crimping tools.
 
Can you not use the car jack to wind the tow bar up until it all lines up. Even if you only get one bolt in loose then you could reposition the jack to get the other bolt lined up and then tighten it all up and away you go.
Tom
 
The things you do, we once broke the front end almost completely off a loaded bike trailer, took a wrong turn on a dirt access track, and it turned nasty, the up and down woops were just too much. 150 km from home and no alternative, we cut down two 50mm trees and, using ropes, they got lashed to the broken front trailer structure and we drove home. I half expected to see the trailer and with 4 dirtbikes sail past us on the Expressway. Thankfully, it didnt.
 
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