Help with starting flat car battery using a Trickle Charger?

With a trickle charger, let it charge overnight before trying to start.

Car Battery Trickle Charger

Trickle Charge Car Battery

You must not try and start the car with the charger still connected. It's not designed to start cars and will be damaged.

Two hours is not enough to recharge a flat battery. The battery will take well over six or more hours to charge enough to start an engine if it's completely flat. It may take several hours longer to charge enough if it's not in good condition internally. Your best option is to leave it overnight but make sure it's in a well ventilated place and sat on a tray (in case of acid spillage).

When you try and start the engine you must switch everything else off: no CD player, no radio etc. and DEFINITELY No Lights. All these things draw current from the battery which you should be using to start the engine. Only turn on the accessories when the engine is running.

If the battery still won't start the engine after being on charge continuously (ie - you have not tried to use it during that period) for over eight hours then it is defunct and should be replaced. Take the old battery to your local council recycling centre, it's hazardous waste and must not just be "dumped".

Your battery was/is completely flat. A trickle charger is designed to keep a battery that is not used a lot topped up. A trickle charger will take 12-36 hours to fully charge a battery depending upon the battery capacity. Starting a car uses' a lot of current.

Evelyn is correct.

If a battery is completely discharged (as in left hooked up in a car that has an ECU or battery presets for months) then it is highly unlikely it has enough capacity to turn over the motor, regardless of whether it will hold 12V or more.

As mentioned, leave it hooked up for 12 hours or more. Trickle chargers need a lot of time to get some juice into a battery. It's free.

If it doesn't start after that amount of time, get a new battery. Going forward, next time you have a vehicle that will be sitting for an extended amount of time, get a "battery maintainer". They won't overcharge a battery (which will also ruin it) and it will still be ready to go when you want to use it. They consume minimal amounts of power, and you leave it on all the time.

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Help with starting flat car battery using a Trickle Charger?

I haven't used my car for over a year so now when i put key in nothing happens so i bought a trickle charger and have connected red to positive and black to negative and plugged in.

Its been charging for about 2 hours now and i have tested the key in car and when i turn on half then the cd...

To consolidate what's been said so far, trickle chargers are called that because that is what they do. They trickle the charge into the battery, i.e. do so slowly, as that is kinder on the battery. Therefore yours will need a long time, at least overnight, to complete the job. Don't keep trying it, all that does is drain whatever charge has so far been acheived.

And, yes, it's is possible your battery is finished if it has been allowed to go completely flat.

Not enough charge in the battery yet - will need many more hours. The battery should not be charged while still on the car and should be charged in a well vented area.

Without knowing the battery capacity and the amount of charge going in no one can give you an exact time but it will need to be left until tomorrow morning ideally.

If it has been left discharged for sucha long time it may take a little charge but not be able to hold much or for long and may have to be replaced.

might not take charge after time left idle.it is reccomeded battery should be charged every 6 or 7 weeks when left idle .use trickle charger for 24 hours then test to see if it is holding charge if not new battery needed . hope it hold charge .