Mine is in a plastic casing with no apparent heatsinks, externally at least. It has six LEDs marked from 1A up to 6.
Tricky for me, since the car is in a very exposed paved area at the front of my house. I don't suppose anyone would take advantage and stroll off with the charger but I'd rather not leave the car with the bonnet unlocked and cracked open overnight. But from what others have said, it might be worth trying the starter after a few hours.
Some manufacturers recommend that you do disconnect the battery. Some cheapo chargers might have a very spiky voltage pattern that could upset the onboard electronics.
Always connect the charger to the battery before switching on the mains and switch off before disconnecting to avoid sparks at the terminals. Especially after charging when there could be a build up of hydrogen around the battery.
Robin asked:
No, there's no option to do that. I don't think it's ancient exactly, just not totally up to date perhaps.
An update:
Charger connected at 9.45am, LEDs illuminated (though tricky to see in the sunlight) up to 5A (6A being the highest).
There was no corrosion on or around either battery terminal, which I take to be a good sign.
So now I suppose I wait and see. Many thanks for all the help.
Ah. I didn't do that...
...but I did do that, since it seemed the sensible sequence.
And I shall do that. Thanks.
Via the OBD socket?
You need a hell of a lot of current to spike a battery over 14v
You were correct. He's talking bollocks #
Modern cars have various "sleep" modes that power various sub systems off after various lengths of time. AIUI there is also a deep sleep mode that can be manually entered that effectively disconects the battery for storeage. How you wake it back up I donno, but cars still do have a physical key and lock.
Though to be honest even a few mA drain will knacker a battery in few months, Solar panel maybe, plugged into the ciggy socket or ODBII? Actually disconnect the battery when parked up on the storeage field? Would seem better options.
I'm sure you could close the bonnet if you put the charger in a suitable place.
the ciggy socket on my car is only live with 'aux' switched on.
Lidl and Aldi sell a very nice little charger for about £14. Small enough to fit in a large pocket. Pretty certain it's a stock item at Aldi online.
But you'd be unlikely to damage your battery any further even if your charger doesn't work, so no harm in trying it.
Indoor only simply means don't use it where it could get wet - under the bonnet etc will be fine, with the bonnet closed.
Depending on the charger, it may not even connect to a very flat battery, though. Due to reverse polarity protection. A very basic old one should be OK. Those usually have a low voltage fuse somewhere.
Leave it on for 24 hours.
A simple 6 amp charger will only charge at 6 amps for a short period (if ever - many are extremely optimistic) and as the battery volts come up, the charge rate will fall.
If the car won't start after 24 hours and the charger was working, chances are the battery has had it.
You can check the charger is working with a simple DVM or other method of measuring the volts. They will be higher on charge than off charge.
Not sure they do. I've never bought a new car, but a few just secondhand with the original battery. And that never has the same life as its replacement. A car sitting in the showroom etc, new or used, is not good for the battery.
If flat, yes. If open circuit, a common failure mode then no current at all.
A good fully charged battery can see the volts rising to beyond 16V without any trouble at just a modest current.
I would suggest rather than putting the battery on charge and leaving it to regularly monitor the terminal voltage.
A battery can still start a vehicle when well past its best. I have a very sophisticated tester made by ACT. That calculates the true battery capacity in amp.hrs. The nominal new capacity is normally printed on the battery case. Once it has dropped to about 2/3rs on a fully charged battery, it won't be long for this world.
How long did you run it for?
With a modern car, it will generally replace the amount taken to start it by the time the engine is thoroughly hot.
I would hope the electronics are designed and tested to a variant of ISO7637.
You'd need an awfully large charger to get voltage spikes past the very low impedance of a car battery.
Properly designed car electronics should have voltage regulators (and components) rated up to 40 volts.
Even with an under engine tray, you can usually feed the mains extension into the compartment from underneath. Assuming it's not a cable reel. If the battery is in the boot, tough. But I doubt anyone would nick a car boot sale charger.
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