As COVID-19 continues to ravage our country, many Americans are driving less and less often. And if your car’s sitting in the garage for months or weeks without running at all, its battery will eventually drain.
Unfortunately, this is a problem you can not solve with a jump starter, despite how fantastic they usually are.
The “good” news is that the pandemic doesn’t seem like it will go anywhere soon, and neither do you. That means you are at home and have a lot of access to tools, auto parts, the internet, and me! So let’s talk about how to recharge a completely dead battery, shall we?
With a battery charger
Before you hook up the battery charger to your vehicle’s battery, I recommend you follow all safety measures and precautions to prepare the battery and battery charger:
- Ensure the car’s ignition is in “off”.
- Check to make sure the car’s transmission is in “park” or “neutral“.
- It is advisable to wear gloves and eye protection.
- Ensure there is no debris or build-up on or around your battery and the battery terminals.
- Don’t connect the battery charger to the wall power outlet yet.
How to recharge the battery
Step 1: Connecting the charger
- First connect the battery charger’s positive wire (red) to the battery’s positive terminal (“+”).
- Then connect the battery charger’s negative cable (black) to the negative terminal (“–“) of the battery.
Step 2: Starting the battery charger
Switch on the mains power supply and turn on the battery charger. You will see the built-in amp meter’s analog display needle dance along the dial. If you have a digital amp meter, you will see the numbers on the LCD screen fluctuate as the battery charger reads and assesses the condition of the vehicle’s battery.
Step 3: Reading the amp meter
The type of battery charger you have purchased may be an automatic or manual charger. A manual battery charger requires you to select and adjust the battery charger’s charging rate and estimate for yourself when it will be fully charged to turn off the battery charger.
But suppose you are using an automatic battery charger. In that case, it will continuously read and assess the battery’s charge condition to charge the battery at the optimal charging rate. Once the car battery has reached its full capacity, the charger will stop automatically.
The amp meter of your battery charger is important to read to establish just how long you need to charge the battery and its condition. If the amp meter shows 100 percent and its needle is lying in the amp meter’s red triangle, then it means the battery is completely dead.
Read more: How to read a battery charger amp meter »
Step 4: Selecting the charge rate
Select the charging rate: depending on your charger’s features, it may provide 2-amp, 10-amp, or even 12-amp charging rates. The charging rate determines how long the battery charger will take to fully recharge the battery. Using the amp meter once more, you can select the desired charging rate. A lower charging rate will take longer, but it will be better for prolonging the life of the car’s battery.
Let’s take a regular family hatchback for an example. Its battery is a 48-amp unit. And to recharge a completely dead 48-amp battery will take about 24 hours on a 2-amp charge rate. If you set the charge rate to 10-amps, it will fully charge the battery in about 5 hours.
Step 5: It’s charging time!
As the battery is charged, the amp meter will display a decrease in the amps flowing through the battery charger. The amp meter’s needle will move from 100% to 80%, then 40% and lower. Monitoring the amp meter’s green triangle, you’ll see the needle move through the triangle towards its apex.
If you have a manual battery charger, when the amp meter displays 0 amp, and the needle is at the apex of the green triangle, it means the car’s battery is fully charged.
For those with automatic battery chargers, these devices will simply shut off once the battery has reached its full capacity.
Step 6: Disconnecting the battery charger
Once the battery has been fully charged, turn off the battery charger and disconnect the power supply from the mains. Remove the negative cable from the battery’s negative terminal and then do likewise for the battery’ positive terminal. This is the safest method of disconnecting your battery charger from the battery.
How to trickle-charge the battery
A trickle charger is another type of battery charger that allows the vehicle’s battery to charge for a longer period of time at a lower amp charge rate. This ensures that the battery doesn’t become overloaded, but it can take up to 48 hours to recharge a car’s battery fully. Trickle chargers are designed and developed to improve and maintain a battery’s condition. These devices kick in to recharge a battery only once a battery has self-discharged some of its power. The trickle charger then feeds energy to the battery that has been used.
There are many benefits to using a trickle charger to maintain your car’s battery. Trickle chargers can prolong a car battery’s life, and these devices have many uses for vehicle owners. For instance, you’ll find classic auto owners using trickle chargers daily to maintain their batteries’ condition. The slow charging trait of trickle chargers means that the internal cells of a battery can be properly and safely recharged to their full capacity. It can maintain the battery’s optimum condition for longevity. Of course, there is one disadvantage to using a trickle charger: don’t expect these to fully recharge a completely dead car battery in 24 hours. These usually operate at only 1 to 2 amps and it can take 48 hours or more to fully recharge a vehicle’s battery.
Step 1: Connecting the trickle charger
Trickle chargers work similarly to battery chargers in terms of their settings and functions. A trickle charger also features an amp meter, a power cable, and two charging wires with clamps to connect to the vehicle’s battery, just as with a battery charger.
First connect the trickle charger to the battery as you would with a battery charger (remember: red wire to the positive terminal).
Then, select the lowest charge rate possible on the trickle charger.
Step 2: Setting the charging rate
Once the trickle charger is connected to the battery properly and safely, connect the power cable to a wall outlet. The amp meter’s display will produce a high-amp reading, and the analog needle will dance along the gauge while it tries to read the electrical current. Once the needle has settled, you will see it come to rest at the highest reading position as your car’s battery is completely dead. Select a charge rate you wish for your battery to recharge.
Step 3: It’s charging time!
Most trickle chargers require more than 24 hours to recharge a completely dead battery. Keep checking on the state of the battery by reading the trickle charger’s amp meter. Once the amp meter’s needle reaches 0, it means that the battery is fully charged.
Step 4: Disconnecting the trickle charger
First, to disconnect the trickle charger, turn off the power supply and remove it from the mains power supply.
Then remove the negative cable from the vehicle’s chassis or engine and then remove the battery’s positive wire. This is the safest way to remove your trickle charger to avoid sparking or damaging the battery.
With another car/battery (using a jumper cable)
Before connecting the jumper cables from another car/battery to your vehicle’s battery, I recommend you follow these safety precautions:
- Ensure your car’s ignition is in “off”.
- Make sure that the other car’s ignition is also in the “off” position.
- Check if both cars’ transmissions are in “park” or “neutral“.
- It is advisable to wear gloves and eye protection.
- Ensure there is no debris or build-up on or around either of the batteries’ and their terminals
How to recharge the battery
Step 1: Connecting two cars
- First connect one jumper cable’s positive clamp (red) to the charged car’s positive battery terminal (“+”)
- Connect that same cable to the positive (“+”) of your car’s battery
- Then connect the second cable of jumper cables by clamping the negative (black in color) to the charged vehicle’s negative terminal (“-“)
Step 2: Turning “good” car on
Now that the two vehicles are connected via the jumper cables, you can turn on the donor car’s ignition and start its engine. Allow this car to idle for 5 minutes to slowly charge up the dead battery in your car.
Step 3: It’s charging time!
Once the charged car has idled for 5 minutes and given your car’s battery to recharge a little, try to start your vehicle. If the car’s engine doesn’t start on this first attempt, turn your car’s ignition to the “off” position for 1 minute.
Step 4: Starting your car
Start your vehicle (the dead one). Hold the ignition a little longer than you usually would. This creates an added draw on the battery to help the starter motor to successfully turn over. Once the car’s engine has started, allow your car to idle for a minute or two.
Step 5: Disconnecting all the cables
Disconnect the jumper cables from both vehicles: start with the positive (“+”) terminal first on your car and then do likewise to the negative clamp. Remove the jumper cables from the donor vehicle’s battery in the same way.
Step 6: Leaving it there for a while
It is important to not turn off your car’s engine. You’ll need to take it for a 20 to 30-minute long drive for the alternator to fully charge the battery.
Calling a trustworthy car care service
If none of the above options work to get your car moving again, there is one more alternative available to you. And perhaps it’s the safest option if you are not comfortable with bursting open your car hood: Calling for AAA or any roadside assistance services available near you.
Your auto insurance company usually offers trustworthy auto care services as an added cover to their insurance policies. You should check with your car insurance provider whether they will cover you for roadside assistance.
If you need a new battery, they will swap one out for you. In rare cases that they don’t have one suitable, they can call for a tow truck to take your vehicle to the nearest car shop. Either way, you are saved from being stranded and yourself!
1. How to tell if my battery is completely dead?
These are the signs that your battery may be completely dead:
- The engine doesn’t even crank or start, and there are no interior lights in the car.
- Your vehicle started just fine yesterday, but today it is entirely dead.
- When you turn the ignition key, nothing happens, and all you hear is a click or a buzz.
- When you open the bonnet of your car, there is a strong odor of rotten eggs.
- You’ve already jump-started the car a few times, but it doesn’t work.
2. Does driving short distances flatten my battery?
Yes, it does. You should drive your car for more than 30 minutes at least once a week in order to allow the alternator to fully charge the battery.
3. Should I disconnect a car battery before charging?
Yes, that is the safest procedure for your vehicle and the battery.
4. How often should I replace my car battery?
Batteries have a lifespan of 5-7 years, so if your battery is beyond that you should consider replacing it. You should also change your battery when it begins to show signs of dying and requires jump-starting too often.