It’s quite essential to keep your car battery charged adequately because it is responsible for providing your car with heating, lighting, starting your motor and functioning wipers. This is especially important during cold weather when you’ll be using more heating and lighting. The last thing you want in the middle of a freezing night is to have a flat battery!
So, it is essential to know how to use a 12V battery charger to keep your car battery charged and ready to go. A car battery charger replaces the lost charge from the car battery using mains current.
Basics of car battery chargers
Most car batteries possess 48Ah, which means that it can deliver 1A of current for 48 hours or 2A of current for 24 hours.
An average car battery charger operates at around 2A which means it will take 24 hours to replace the lost charge in a flat battery fully. You can, however, find car battery chargers that charge at different rates ranging from 2 to 10 A.
Before you choose a battery charger, ensure that it is compatible with your car battery. A battery delivering a high current can charge your battery quicker, but it could also distort the battery plates.
Things to consider before using a battery charger
• Make sure to check the electrolyte level before hooking up the charger to the battery. Clean the battery posts if there’s any corrosion build up and fill in more electrolyte if needed.
• A battery that is approaching the end of its useful life may not charge properly and will not store the charge.
• The mains lead on all battery chargers has to be fused. If not, use a 3-pin fused plug.
• A basic home charger can deliver from 3-6 A if the battery is in excellent condition. Home chargers have built-in transformers and rectifiers to convert the 110/220 V mains AC to 12V DC.
• Some chargers come with a high and low charging rate options, usually either 3A or at 6A. If you want a quick overnight charge, use the 6A. Use the 3A for a longer charging time.
• There are smart chargers out there that automatically switch off the charger once charging is complete or reduce the current as full charge is approaching.
• Higher amp chargers can charge your battery quickly but take caution not to overcharge and damage the battery.
• Make sure to unplug the charger once the battery has been fully charged.
How to use a 12 V battery charger
Ensure that you have a battery charger that can sufficiently charge a 12 V battery. A 10A charger is the most suitable for a 12 V car battery for a fast, smooth charge. You can use a higher Amp rating to get a faster charge but charging too fast can damage the battery plates.
Connect the positive lead from the charger (conventionally colored red) to the positive (+) terminal of the battery. Clamp the negative lead from the charger (black colored) to the negative battery post.
Plug the charger into the mains socket and turn it on. An indicator light will light up to show the battery is charging. The gauge (ammeter) will show a high current flow at first, but this will gradually decrease as the battery approaches full charge.
Towards the end, the cells will start producing gas, and you’ll see bubbles. If one cell starts gassing heavily prematurely, the battery may be faulty.
• Ensure that you unplug the charger first before removing the terminal clips. Otherwise, it may start sparking and ignite the gas given off while charging.
• Turn off all electrical circuits before connecting the charged battery. It may cause sparks and ignite the gas given off during charging as well.
• Please learn how to use a 12 V battery charger thoroughly before attempting!