How Long Does It Take To Charge A Car Battery While Driving?

A dead battery can be a big pain. Once upon a time, I owned a Mercedes that had a problem with battery drain. I had to jump-start every other morning. The alternator, on the other hand, could quickly charge the battery.

Most automobiles will charge a flat healthy battery in around thirty minutes of highway travel without the usage of electrical parts such as lights, HVAC, or wipers.

In this article, we’ll go over how to power a battery while driving and the dangers that come with it. We will also go over how to check the health of your battery and alternator, as well as what to know before detaching your battery. Let us know how long to drive a car to charge a battery.

What is the process by which a car battery charges itself?

The engine’s power is used to replenish the car battery. The battery gets more juice the more you use the engine. The alternator is used to replenish the car battery in most new automobiles.

When the engine is operating, energy is generated, which causes a chemical process to replenish the car battery. The alternator is an electromagnet that is turned on when the serpentine belt is engaged. The serpentine belt is then attached to the car’s engine. The serpentine belt turns when the engine is started supplying power to the alternator.

This may appear to be a complicated arrangement but it is critical to understand how your car works in order to better care for it. This is an excellent resource for understanding how your automobile battery works.

How much time does it take?

However, rather than learning the technical intricacies of how the battery charges, knowing how long it takes to charge may be more practical. If you’re stuck somewhere and your battery seems to be low on the odometer, running the engine is one of the first things you had do to recharge it.

Car idling along the highway.

Even if your engine is turned on but only idling, the alternator will turn on if it is in good working order. You can leave the engine running while still parked in the parking lot, and the engine will charge the battery with electricity.

The length of time it takes for the battery to charge while driving is theoretically determined by how much charge it had to begin with. The answer to this query will vary based on the age of the battery, the length of time the engine has been off and the condition of the alternator.

When your battery starts to fail, it is usually because your alternator is not supplying the battery with the necessary voltage to charge it (12.6 V). It should not take long for the battery to charge while driving if you have a fully functional alternator and a healthy battery.

The battery should charge in less than 30 minutes if you’re traveling on the open road and your engine RPMs are suitably high. The engine RPM will naturally be below if you’re driving in the city and have to stop frequently at stoplights or in traffic. The battery may take over an hour to charge in this instance.

High RPM as shown on the car’s dashboard.

It should not be a problem in any case as long as your alternator is in good functioning order. If your capacitor is in good operating order and your battery has not expired, your automobile should not offer you any trouble.

The best approach to charge your battery is to drive it. In the event of an emergency or when your battery dies and you need to jump-start your automobile, you can use it any other way. Trickle chargers are another option for charging your battery, but nothing beats driving your car and keeping your engine running to charge your battery efficiently and quickly.

Quick Charging Instructions

It’s evident that a dead battery is uncomfortable, and it still happens when you’re rushed for time. I understand. I’ve been through it for a few months now. When jumping starting your car from another vehicle, here are a few pointers on how to charge it as fast and efficiently as possible.

  • Connect the batteries to the jumper and take off the donor car’s engine at around 3,000 RPM before jump-starting your car, for a period of five to 10 minutes. This will be beneficial to recharge your flat battery while also reducing the burden on your alternator.
Car engine jump-start between two vehicles.
  • Switch off all electric consumers, including heated leather seats, HVAC, rearview warmed screen, lighting, wiper, and infotainment systems, on both cars before jump-starting. Leave the vehicles linked for several moments after they’ve been jump-started, with the motor running above idling.
  • After removing the wires and shutting off any electrical consumers, drive at motorway speeds (or as much as can). If at all possible, avoid conducting the jumpstart process at night as you’ll need to utilize lights when driving.
  • When you turn off your vehicle after a thirty-minute ride, your battery must be fully charged. However, if the problem is caused by the battery or another component, you may have the same difficulty. So, if you’re able, park in a position that allows you to access your battery in case you need another jump start.

Recharging Possibilities By Driving

Car battery charger.

The dangers of driving your car to replenish a dead battery are minor, but they exist. You should be aware of the potential risks without being overly concerned. To replenish your car battery is at least 12.5 volts, you should always utilize a battery charger.

Charge the battery while driving

Check out the NOCO boost pack if you are looking for an excellent compact starter and battery booster. I bought one and was blown away by just how amazing it is. In my twenty-five years as a mechanic, this is the quickest charger pack I’ve ever had.


As you may be aware, modern automobiles are jam-packed with gadgets. Such dudes all need a certain amount of power to function, so if the device isn’t fully charged, some functions may be unavailable temporarily.

Charger for batteries

It is usually not a major issue. Only non-essential equipment, like radios and heated seats, is turned off by the computer. The problem is that even if indeed the battery is charged fully charged some cars may require a journey to such a dealership to re-calibrate sensors in order to restore operation.

You can calibrate your vehicle on your own, however, you will require a reliable scan instrument to do so.

Workload on the alternator

It’s a hefty task to recharge your capacitor on a dead battery. It’s capable of doing so, however, it isn’t intended to do so. Your alternator gets to operate when you just begin your automobile with something like a wholesome 12.65-volt battery. It gives electricity to all of the vehicle’s electronics.

A car alternator inside the engine converts mechanical energy to electrical energy.

At this point, the automobile battery has done its duty, and it anticipates the alternator to recharge it once all other systems are operational. When you ask to charge the capacitor with a completely dead battery, you are putting a lot of strain on it. Its life will be cut short if you ask it to perform this on a frequent basis.

Alternators can be fixed, however, they are frequently replaced with new ones. A new alternator can set you back a couple of hundred dollars.

Belt drive

When operating a vehicle to recharge the batteries, the auxiliary belt can become overworked. The alternator is driven by a belt. Under these conditions, it may break if it is worn.

An engine’s auxiliary belt

The issue is that the aux belt is usually utilized to power other components such as the steering systems, water pipes, and cooling fan. If it breaks down, you will be towed away.

Belt in the engine car.

Checking the Health of Your Battery

Jump-starting and driving your automobile will not replenish a flat battery caused by a fault with its battery as well as an alternator. The jump-starting technique may offer enough power to have the performance on the street, but the engines will shutter after several miles if the battery is exhausted.

A man holding a multimeter to check the voltage of the car battery.

Final Thoughts

People don’t think about their car battery until it dies on them when they first start to drive. For an inexperienced driver who has taken the car out on their own, this might be a stressful situation.

In such a case, one is at a loss on what to do. What happens if the battery dies again, even if you receive some help jump-starting the car? For all of these reasons, I believe it is beneficial to learn about your car battery and how to care for it at a young age!

They’re cheap, but they will save you a huge amount of cash. In good manuals, you’ll find maintenance diagrams, schematic diagrams, system functioning overviews, debugging chapters, fastening torque standards and sequences, and other mission-critical information.

What have you discovered? If you have any questions about this issue, please leave a comment below. You can also leave your thoughts after reading the information above.

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About Brock Rangel

Hi, I am Brock, and I am the lead editor/photographer for TheCarColony. I have been a mechanic for over 14 years now, and I am here to spread my car knowledge across the web!

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