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Charging car battery via the accessory socket?

Discussion in 'Electrics, Vacuum, Ignition and ECU' started by L John, Jun 25, 2017.

  1. umblecumbuz

    umblecumbuz Senior Member

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    Good thread, this. I've just bought the Sealey 1100 unit from Ebay. £160, as opposed to Toolstop's new price of £179. Either is post free.

    Although I have a seperate power pack for use in my camper (as opposed to a leisure battery and relay system) I tend to use the car's battery also for a few accessories - mostly when I forget to swap to the power pack when I park up. This Sealey unti will be a good emergency stand by.
     
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  2. OP
    L John

    L John Senior Member

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    Excellent. Perfect for your situation.
    I love the fact its small and light but unlike Li-ion, I never have to worry about keeping it charged.
    It will also last many years so it will outlast several of the cheaper units and always have a strong output.
    A great investment.
     
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  3. Pathfinder

    Pathfinder Senior Member

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    I would just buy a new car battery, save myself all this hastle and cost.
     
  4. OP
    L John

    L John Senior Member

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    Why buy a new car battery?
    There's nothing wrong with mine or anyone else's on this thread as far as I'm aware.
    Not sure what all this hassle is that you're talking about either. No hassle at all.
    You are right about the cost though.
    If it only lasts 10 years it would have cost £16 a year to have it there, just in case it's needed.
    Likely to last much longer but even at £16 a year I'm not overly worried about it.
     
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  5. LostKiwi

    LostKiwi Senior Member

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    Even brand new batteries go flat if you leave something on sometimes....
     
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  6. Pathfinder

    Pathfinder Senior Member

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    ok, I will go and get a charger then.
     
  7. umblecumbuz

    umblecumbuz Senior Member

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    The use I've put my jump leads and also my iCarsoft scanner to over the years has been more to help other people in an emergency than to get my own car started/scanned while at home. Hopefully my new Sealey 1100, when it arrives, will simplify this.

    You can't easily buy a new battery or charge your car when you're stuck away from home. Try doing that after a few weeks in an airport long stay car park!
     
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  8. OP
    L John

    L John Senior Member

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    Hope you've got a long lead for it in case you get a flat battery away from home then. Or wait to be rescued.

    Obviously you don't want a jump starter of any sort. That's fine but some people do want one even when they have no need for one today, tomorrow, next week etc.
    Some people just like to be prepared.
     
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  9. LostKiwi

    LostKiwi Senior Member

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    I've had a couple of instances of flat battery recently.
    The first was when loading the car for a trip. The doors were opened and closed and opened and closed due to the rain as I was loading. Each time a door opened the interior light came on and eventually flattened the battery to the point of non starting. This was discovered next morning when we prepared to set off for the ferry.....
    Not normally an issue as I'd just use jump leads to restart but the only car available was the 230 and jump leads go nowhere near it. Besides which the jump leads were buried beneath the packing as thats where I keep them normally (210 has a great little place under the seats). Fortunately I have a 10A CTEK charger which was able to ram enough power in quickly enough to get us going (thank god I always allow an hour contingency!).
    Second time was the 230. I was running Diags on it with the key on and it took the battery down over a period of time. Again the CTEK came to the rescue. In hindsight it would have been better to connect the CTEK before starting diags.
    The only problem with the CTEK as a rescue device is it takes over 45 minutes to get enough charge in. Fine if you have 45 minutes to spare but it was a bit nerve wracking when you have a ferry to catch.

    I'll definitely be investing in a decent jump start device soon.
     
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  10. Pathfinder

    Pathfinder Senior Member

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    That's why I said I'm going to get one. How long a lead do I need to buy for it?
     
  11. EmilysDad

    EmilysDad Senior Member

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    I've found that 'smart' battery chargers won't start to charge if the battery has become really flat. An old fashioned dumb charger needs to start it off.
     
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  12. LostKiwi

    LostKiwi Senior Member

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    Yeah I found that too. I have a small 12v battery (way too small to start off) which I clip in parallel to get the smart charger to kick in.
     
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  13. Pathfinder

    Pathfinder Senior Member

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    Last edited: Apr 17, 2018
  14. umblecumbuz

    umblecumbuz Senior Member

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    That's a different animal to the condenser-run Sealey unit.

    I have a similar thing, but with a bit more oomph and a built-in 240v 300 amp convertor, that I keep in my camper for running accessories when off grid. It will obviously start your car in an emergency. The downsides are - it's a big heavy lump, and ideally needs to be anchored if you keep it in the car - and it needs regular charging if it's to work properly (and that's a memory problem, because charging intervals without use are around every three months, easily overlooked).
     
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  15. Pathfinder

    Pathfinder Senior Member

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    Expensive. I think I may put buying a charger on hold meantime and hope my battery last for a few years yet.
     
  16. LostKiwi

    LostKiwi Senior Member

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    A charger and jump start pack are totally different things. A charger is a device that runs from the mains and takes several hours to fully charge a battery (depending on charger/battery maybe as long as 12 hours or even more).
    The jump start packs we're talking about in this thread are an emergency get you going device for when the battery is flat and you need to get going straight away.
     
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  17. Pathfinder

    Pathfinder Senior Member

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    I have jump leads for that, so no point in me investing.
     
  18. umblecumbuz

    umblecumbuz Senior Member

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    For jump leads to be any use in an emergency, you need another car nearby! Not always available.
     
  19. LostKiwi

    LostKiwi Senior Member

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    Yeah me too but there is no way I'd jump my 230 from another car. This on the other hand should be a safer option.
     
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  20. Pathfinder

    Pathfinder Senior Member

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    I'm not buying one. There is always someone to provide a jump start.
     

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