How to Charge a Completely Dead Car Battery

Since the pandemic began, all of us are driving less and less. With cars left standing in the garage, there is a risk that your car battery may drain and ultimately become completely dead.

However, knowing how to fix a completely dead car battery can help you get back on track. So let’s just get into finding a solution for how to charge a completely dead car battery.

Read ahead to know all about it!

Table of Contents

How to Charge a Completely Dead Car Battery?

There are multiple ways to revive a dead car battery, However, let me be honest with you, if you have a completely drained car battery, nothing can be guaranteed about it. However, you can still try. Have a look at the following methods.

As simple as it can get, you can charge your dead battery completely with a 2 amp or a lesser trickle for about over 24 hours.
A new gadget- some of the high-tech “smart chargers”, can help you fix the batteries which are less than 2.5 volts.
A pair of jumper cables connected to the good battery with a dead car battery is another method of reviving your car’s battery. It is important to note that batteries must be connected in parallel i.e. + to + and – to -. Now, connect the charger to the good battery. This method will deceit the charger to see good voltage and thus would charge both the batteries. Once your dead battery would show a good charge over 10 volts, the charger can then charge it properly.
You can also jump-start your car. All you need are the jumper cables and an external source of battery (some other car). Connect your dead battery to the battery of another vehicle for a jump start.
A battery maintainer is another way to fix car batteries. However, it can never fully recharge a completely dead battery but there still might be a chance! Therefore, hook the battery to the charger to lift the charge. Once the charge gets back up, you can maintain the charge with a battery maintainer.

How to Charge a Dead Car Battery at Home?

Well, there is no need to worry. There are many DIY methods to charge the dead battery at home as well. The hassle of dragging your car is over.

Among many of the DIY methods to charge a dead car battery at home, two are the most reliable. You can either charge with a battery charger or other electric appliances at home. Sounds intriguing right?

Have a look at the following methods for a quick fix for a dead car battery.

Charge with a Battery Charger

Firstly, take out the battery from your car. It’s important to keep in mind the correct arrangement of screws and attachments.

Now charge your battery with a battery charger by connecting it to the respective terminals.

Once done, place the battery back into its place with an accurate terminal connection and you must be good to go!

NOCO battery charger works perfectly for completely dead batteries as well. Its compatibility with an extended range of vehicles and automatic functioning makes it a winner! Check the Latest Price on Amazon.

Charge without a Battery Charger

Nothing has worked out for you so far? I can understand. There come situations when your car battery gets dead and the charger remains absent.

You don’t need to worry, here are some of the ways to charge your battery at home as well!

First Method:

If you have a laptop, then its charging adapter can help you fix the battery issue. The adapter can usually provide an output of 18-19 volts.

Thus, along with the adapter, take a 12-volt bulb with power ranging from 5-50. However, it is important to note that the higher the power of the bulb the higher the charging current.

But, for the safe side do not raise the power more than 3.5 or 4 amp. Connect the entire scheme in series and hook a multimeter to have a constant display of the value of current passing through.

2. Second Method:

For this method, take a bulb of 220/110 volts, 40-100 Watts. The lamp works as a current limiter and then attaches the diode and lamp in series. Make sure to connect the neutral wire of AC to the negative terminal of the battery with the help of a voltage tester.

Connect the last end with an AC adapter and let the circuit charge the battery for restored functioning.

3. Third Method:

This method is similar to the previous one except that the diode is replaced by a diode bridge (full wave rectifier). Want to know where to get that from?

Well, you can remove a suitable bridge from an unused computer desktop. However, please understand that it might be dangerous for electric shock.

4. Fourth Method:

For this method, you can use a computer power supply unit of any size and voltage. Among ranges of voltages, use a 12 volts bus.

But as 12 volts are not enough for a car battery, there are ways to maximize it. For this, you need to shorten the wires as they will allow you to run the power supply without connecting to a computer.

Or else, you can use a 20-50 watt halogen bulb as well. For better understanding follow the above diagram.

Very Important Note: All these DIY methods should not be practiced regularly as they can be damaging to the car battery. Moreover, there is a risk of electric shock so, all these methods need to be handled with care and electric gloves.

How Long do You Need to Drive a Car to Recharge a Dead Battery?

It usually takes a 30-45 minute drive to recharge a battery. Or else, let your car sit idly in the driveway for a while for it to work. But what if the battery is completely dead?

In such a scenario, do not keep the car running. It is because driving puts a lot of pressure on the alternator and can burn it completely.

If the car battery is completely dead, a ½ hour drive would only trickle it a bit to start on keys. However, the battery would still require a decent charge to get it back for regular use. Thus, no amount of drive can recharge an extremely discharged battery.

The only reliable way to fix such batteries is to use a smart battery charger. Keep the voltage high enough to mix battery acid smoothly in the electrolyte. Moreover, this process can help you avoid both damage and fuel and above all restore the battery to maximum charge as well.

Are you looking for a smart charger? Well, the Schumacher battery charger right here can be used with multiple cars and batteries. All you need to do is to adjust the ampere to function perfectly.

If you need a charger that can jump-start your car as well, this is the one. It is best suitable for dead batteries. See the Latest Price on Amazon.

How Long to Charge a Car Battery?

How Long to Charge a Dead Car Battery?

Well, time duration depends on the battery size, health, and charger. If it’s a 50% threshold with 2-3 amps trickle can get it back within the period of 24 hours. Moreover, if the battery is completely dead, it also depends on the charger for how long it’ll take to charge the battery.

Ideally, a 60 Ah car battery takes 30 hours with 2 amps. If you are taking 15 amps, then it takes 4-5 hours to charge it completely.

But, let me be honest with you, 2 amps is safest to avoid any damage. To your surprise, if the battery is completely dead, it takes up to 48 hours to charge it as well but happens rarely.

How to Charge a Dead Car Battery with a Charger?

Now that you have substantial knowledge of different methods to revive a dead battery, it is time for a walk-through of the steps to follow when using a charger.

Keep the charger unplugged at connecting the red wire with the positive terminal of the battery.
Connect the black wire with the unpainted area of the chassis. Remember to keep a safe distance from the battery
Now plug the charger and set the voltage and ampere level.
Ideally, 10 amp works best for a 12-volt car battery. Let the charging continue as per instructions on the manual.

But Wait!! What If the Car Battery Won’t Charge on Charger

If anything like this happens, then in such a case, use a jumper cable to assist the charger thus charging a completely dead battery.

As discussed earlier connect the dead battery with a healthy battery in parallel and deceit the charger.

Ideal for use in jump-starting a car, these cables come with stronger clamps made of solid copper.

Having these jumper wires with strong reliable wires can help you fix a car in distant parking spaces. Check the Latest Price on Amazon.

How to Charge Car Battery with Another Car?

Jump starting is one of the safest ways to charge a dead battery as it’s a lot easier. You simply need to have jumper cables and a car with a functional battery.

Firstly, find a car with a working battery. Line up the hood of both functional and nonfunctional cars near each other, but make sure they don’t touch!
Now turn off and unplug everything (including radio, air conditioner, etc.)
Start locating terminals of the battery. One can find them easily since they are marked on batteries.
Keeping an eye for color-coded wires, attach the positive terminal of the dead car battery with the positive of the working one.
It is important to remember, do not to connect the black clamp to the dead battery’s negative terminal once the other clamp attaches to the working battery.
This clamp goes on a metallic part away from the battery. The purpose of this is to complete the circuit. You might notice small sparks that are pretty normal.
Now, all cables are set, start the engine and let it run for a minute or two before starting the dead battery. Keep the engine on for 30 minutes to fully recharge the battery.
Finally, remove the wires but keep the engine running for a while. Amidst all, make sure to not let clamps touch each other and disconnect in the reverse order.

To Sum It Up!

With tons of tips and fixes, it is now possible to recharge a completely dead car battery. Do not let a flat battery disrupt your plans! Depending on the situation and condition of the battery, you can now handle it yourself. However, in case of further complications, feel free to seek professional assistance.