Battery drains when standing still

April 25, 2022

Car is standing still for too long

Maybe you worked at home for a longer period of time because of the corona virus, finally had a flying holiday again or your car was broken. If you want to leave your car after a longer period of time, it may just be that it does not start because the battery is empty. Bale of course.

Battery loses voltage

Every battery slowly loses its voltage. This is partly automatic, but also because the electrical systems on board always use electricity, even when the car is parked and locked. Think of the alarm system. And of course if you forget to turn off the lights. Over time, your battery will be empty…

Battery life

The normal lifespan of the battery in your car (with combustion engine) is between three and seven years. By taking good care of it – read: using your car regularly – you optimize the life of the battery.

Starting your car consumes a relatively large amount of electricity, especially if the engine does not start right away. And while driving you also use electricity for the ignition and when you switch on the lighting, the radio and all kinds of other equipment in your car, such as the air conditioning.

But that does not matter, because while driving, the dynamo generates the necessary power. The power that is not used is stored in the battery. You then have to drive more than a few kilometers, because starting is a heavy drain on the power supply in the battery.

Battery on trickle charger

Are you planning to not drive for a longer period of time, due to holidays or the extreme fuel prices? Then you can take precautions to maintain the battery life – and the voltage. For example, put your car or just the battery (don’t move and don’t drop it) in a place with a socket. Then you can connect the battery to a so-called trickle charger. It keeps the battery in good condition by charging it pulsating. Then the battery ‘works’ in approximately the normal way: it discharges and is recharged again and again. Connecting to a trickle charger is already a good maintenance measure for the battery after a few weeks of standstill and cold.

Empty battery: jumper cables…

If you discover that your battery is empty, you can call on starting assistance from the ANWB or a local garage. Or you can try to start the car with jumper cables and the neighbor’s car – but be careful, because you can damage the battery and the electronics of the car if you do it wrong. And if you manage to start the engine with cables, the battery is far from being charged. You then have to make a good ride to bring the battery voltage back up to standard.

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Starting with empty battery and jumper cables

Ask the neighbor to help you with his car. Turn off the engine of the neighbor’s car, as well as all power consumers in both cars.

To avoid short circuits, connect the jump leads in the following order:
one clamp of the red jumper cable first to the + pole of the battery in the neighbor’s car and then the other clamp of the same cable to the + pole of the empty battery
the same for the black cable: first a clamp on the –-pole of the neighbor’s battery and then the second clamp on the –-pole of the empty battery

Start the engine of the neighbor’s car and let it run for a while before starting the car with the empty battery. Have the neighbor give his car a little gas if your car won’t start.
Run both engines. Because a peak voltage can arise when the jumper cables are disconnected, you first turn on some power consumers in both cars to absorb that peak.
First disconnect the black jumper cable from the car with empty battery and then that of the neighbor; Ditto with the red cable: first from your own battery and then the other.

Thank the neighbor for his help and immediately take your car for a ride to recharge the empty battery. Do not stall the engine, as the battery is not yet fully charged.

… or empty battery on the battery charger

If you can spare the car for a day/night, you can also connect it to a battery charger. Be careful that you connect the cables to the correct poles and make sure that you do not charge the battery too far. Also make sure that you set the correct charging voltage. During charging, the so-called oxyhydrogen gas can be formed – a highly explosive mixture. And an old-fashioned ‘boiling’ battery can splash and those splashes of battery acid burn holes in your clothing. Place a charging battery on the charger in a safe and well-ventilated place.

Broken battery, but not stood still for long?

Have you just used the car, but the battery is still empty, without having used many power consumers? Perhaps the battery is not only empty, but even broken. If it is clearly before the end of its life, have the voltage regulator and alternator checked at the garage. If the alternator is broken, the battery will not be charged while driving. If the voltage regulator is not in order, the charging voltage may have been too low or too high. Then the battery gives up the ghost.

Don’t just throw away an empty battery

A battery is never completely empty – just think of the battery packs of electrically powered cars, which are reused elsewhere at the end of their life for energy storage. The batteries we usually deal with are conventional batteries. They contain battery acid and lead. That’s junk that you can’t dump in the garbage. Hand them in neatly at a collection point, for example where you purchase your new battery.