A dead car battery can be caused by several reasons. If you are looking to charge your battery efficiently, then you are in the right place.
Did you stop using your car for a long period, parked your car outdoors in freezing climates, or forgot to switch off the headlights or interior lights of your car? All these can cause your battery to die. So, In case this happens to you, do you know how to charge a car battery?
There are multiple ways to charge a car battery. You can do it with a charger, without one, using another car, or even with the help of a generator or solar panel. For the most part, it is a DIY project that you can carry out at your home but, if the problem persists, don’t hesitate to consult a battery specialist!
Car batteries consume the extra power generated by the engine, and most of them have an extended lifespan. They last for about 5 years or more without any need for replacement or recharging.
But even the ones that are of the highest quality run out of power with time. A dead battery can be a huge inconvenience for anyone. Learn to charge your battery effectively and efficiently with our following mini guide.
Before we start with the charging process, you need to take some safety precautions!
Necessary Safety Measures for Charging a Battery
• You need to wear protective eyeglasses in case the battery malfunctions. This is to prevent any dirt, battery fluid, debris, falling particles or sparks from damaging your eyes.
• Put on some gloves; although not mandatory, they are highly recommended. They provide better grip on heavy equipment and can reduce the risk of receiving electric shocks, small pinches, and cuts.
• Remove any metal jewelry to avoid the risk of shortening the battery.
• See that the area you are working in is properly ventilated and has enough lights for you to work with ease.
• Keep children away.
1. How to Charge a Car Battery with a Battery Charger
Charging a car battery with a battery charger is relatively inexpensive. A battery is considered dead or flat when it has lost its charge. A charger simply replaces that charge through positive and negative leads.
Choosing the Right Battery Charger
There are various battery chargers available in the market. Ranging from one that charges approximately 2 amps per hour and needs a complete day to fully charge a flat, 48amp battery up to the one that charges around 10 amps an hour.
The higher the charge output, the faster your car battery’s charging; however, fast charging can cause the battery plates to deform.
Connecting the Charger
• Firstly, check the electrolyte level. See that it is just covering the battery plates. If the level isn’t as desired, top up the battery and remove any dirt from the battery posts.
• If there’s a socket nearby, you can leave the battery inside the car. Make sure that the charge rate remains around three to four amps.
• In case of a car with an alternator, detach the terminals before you start with the charging to avoid damaging the alternators.
• If the cell caps are attached separately, allow for ventilation by detaching them. If the charging rate is low, leave the trough covered.
• Now distinguish the positive lead from the negative lead. The positive one is usually red in color and needs to be attached to the positive battery post. The negative lead, usually black, is to be clamped to the negative terminal.
• Plug the charger into the socket and turn the power on. If the indicator light turns on, it means the battery has started to charge. The gauge also indicates a charging battery. It may indicate fast charging in the beginning, but as the battery keeps getting charged, that drops.
• While your battery is charging, use a hydrometer to check the charging level.
• Once the battery is fully charged, the cells bubble and release gas. If the cells start gassing randomly then the battery might be faulty. The best thing to do at this point is to get it checked by a professional.
Unplugging the Charger before Disconnecting it from the Battery
It is important to turn off the power and unplug the battery charger once your battery is fully charged. As discussed, the cells tend to bubble and give off the gas at the end of the charging.
If you try to remove the terminal clips without turning the power off, they may spark and ignite the gas. In addition, while reconnecting the battery, make sure there aren’t any electrical circuits switched on in the car to avoid any sparks or gas ignition.
2. How to Charge a Car Battery without a Charger
Although using a battery charger is the most efficient way to charge a flat battery, it is not always possible. If you are stranded somewhere with limited availability to resources then you need an alternative that won’t require much equipment.
However, taking necessary safety measures step is mandatory to be implemented before you start with this process.
Things You’ll Need
• Electrical Tapes
• Wire Stripper
• An alternative for the battery charger
Selecting an Alternative for the Battery Charger
You can use any charger used to charge an electronic device such as a laptop. Start by finding a charging device that has a similar voltage potential as compared to a battery charger.
This is to ensure that the charge that your car battery needs are delivered to it. Once you find a perfect alternative charger, start making the necessary connections!
• To fulfill the absence of a battery charger, you need to mimic its functionality a bit. Start with finding an alternative for the positive and negative leads of a charger. Use two new cables for the purpose. Take a cutter and strip off some of the rubber from the two end corners of the cable to expose the wires inside. Now bend the wires to create a loop that you can twirl around the power cell nodes.
• For the negative lead, make loops on both end corners of the cable and for the positive one, make a loop on a single end. To distinguish between the polarities of the two cables easily, you can color the cables with a permanent marker.
• Now twirl the loop end of your negative cable around the metal portion of the alternative charger’s end node (connected to the device) and tape it using some electrical tape.
• Wrap some aluminum foil around the exposed corner of the positive cable. This end will be used as an alternative to a charger’s plug. Compress the cable firmly inside the metal tube to avoid any sparks.
• Make sure that no ends meet other ends of the cable.
• Connect the free and looped ends to the positive battery post and the negative terminal and double check the connections before turning the power on.
• Turn the power on and start the charging process.
Note: This is a risky method. Along with taking the above-mentioned safety measure, keep a fire extinguisher nearby in case of any emergencies.
3. How to Charge a Car Battery with Another Car
Yes, you read it right. Along with your car with the dead battery, if you have a second car with a fully charged battery, then all you need are jumper cables to fix your problem.
Learn how to connect the two batteries and charge the flat one using jumper cables in a few simple steps.
Steps Prior to Jump-Starting
• Check your car battery for any faults. The battery is most-likely defective if it has some cracks or is leaking battery acid.
• If the battery is, in fact, defective or is showing signs of malfunction then do not attempt jump-starting as it can cause injuries to you and others nearby.
• Once again, taking extreme safety measures are a must for maximum protection.
• Check the cables connected to the battery for any corrosion.
• Place the two cars side by side or facing each other nose-to-nose. The distance between the two cars needs to be appropriate enough for the jumper cables to connect them together with ease.
• Use two jumper cables of the same length. Connecting a shorter cable might cause a fire.
• Turn off the car with the charged battery.
Steps for Jump-Starting the Flat Battery
• Open the front bonnet of each car, under which the batteries are located.
• Distinguish the positive and negative terminals with the symbols plus (+) and minus (-) respectively.
• Now connect the cables with the battery terminals in the given order. Start by connecting one end of the positive jumper cable (it is likely to be red in color unless labeled otherwise) to the positive terminal of the flat battery and connect the other end of the same cable to the positive terminal of the functional charged battery.
• Connect one end of the negative jumper cable (it is likely to be black in color unless labeled otherwise) to the negative terminal of the functional charged battery.
• To ground the car with a flat battery upon jump-starting, find a grounded metal component in it and connect the other end of the negative jumper cable to it.
• To start the charging process, start the functional car’s engine with the charged battery. Allow it to run for about 5 minutes.
• Try to start the car with the flat battery. If it fails to start, let the engine of the functional car run for five more minutes.
• Once the engine of the dead battery car starts, this indicates that the battery has sufficient power to do so, although it may take a lot longer for it to fully charge.
• Now as with the connection, the disconnection also needs to be executed in a specific order. Remove the cables in the reverse order in which you attached them to prevent any sparks from occurring.
• Let the car with the dead battery run for about 5 more minutes to allow the alternator in the car to kick in.
• Drive the car after jump-starting it for about 15 minutes.
• However, if your car fails to turn on, you might need to call a battery specialist on board or purchase a new battery altogether.
4. How to Charge a Car Battery with a Generator
Along with chargers and functional cars with charged batteries, generators can also be used to charge a car battery. The AC power produced by generators is converted by the battery charger into DC power to charge a dead car battery.
Things You’ll Need
• Gas generator
• Battery charger
• Firstly, any low fluid levels in the generator need to be inspected and corrected for efficient battery charging.
• Now distinguish the positive lead from the negative lead. The positive one is usually of red color and needs to be attached to the positive battery post. The negative lead, usually black is to be clamped to the negative terminal. Connect the leads with their respective terminals.
• Make sure that the charger isn’t powered on.
• Turn on the generator with the start cord or switch.
• After you’ve turned the generator on, wait for about 2 minutes for the stabilization of the engine speed and voltage to avoid causing damage to the connected charger.
• Connect the charger to the 110-220V AC outlet located on the generator and turn the charger on.
• If all the connections are correct, the battery should be charging at this step.
Figure Out the Real Problem
If you are certain that your car battery died because of freezing temperatures, leaving the headlights or indicator lights on when the car was turned off, or any other valid reason then opting for a battery charging solution is the best decision.
But if you did everything right and the problem still persists, the electrical system of your car might be the actual problems. If that is the case, your battery is most likely to go flat again or go weak.
Here are some signs to take into notice before you start with the above processes:
• Your car takes longer than usual to the start and the engine keeps slowly cranking when you attempt to do so.
• Check your check engine light as sometimes it indicates a weak battery.
• Check if the fluid level of your battery is sufficient enough. This is relatively simpler to do as the container is usually translucent and easily observable.
• Check if your battery casing has swelled or melted because of excessive heating.
• Check for battery leaks. You can verify them by checking the negative and positive terminals. If they are corroded or filled with gunk then it is very likely that your battery has a leak.
• Your battery has reached its maximum age.
Look for all the signs above and if you believe that your battery is irreparable, consult a technician. They can test your battery for you and come with an appropriate solution.
1. How to Charge a Dead Car Battery – wikiHow
2. How to Charge a Car Battery – meineke
3. How long does it does it take to Charge a car Battery with a 12 volt charger? – BEST OF MACHINERY
4. How to Charge a Battery with a Generator – It Still Runs
5. How To Jump Start Your Car – Guide For Using Jumper Cables To Charge A Dead Car Battery – CarOne