The car battery is a crucial part of the engine, but our curiosity makes us wonder what will happen if we just removed it and tried starting the car without it.
Your car cannot start without a battery, but it’s possible to take the battery out while the engine is running. This is not recommended as it poses a serious risk for all components due to voltage spikes.
The answer to this question is more complicated than it seems, so in this guide, we’ll discuss how the vehicle charging system works and why the battery is a crucial part of the engine.
The alternator and battery work in tandem to deliver electricity to the vehicle. The power is needed to turn the starter and crank the engine, but also to run headlights, the ECU and various chips and computers, the dashboard, radio, etc.
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Think of the car battery as nothing more than a massive phone battery. It has a certain charge capacity that is drained and refilled in cycles.
The battery’s main job is to deliver a surge of power necessary for the starter to crank the engine. It also keeps the radio, lights, and other electric consumers going when the engine is off.
Another major function of the car battery – and the most important to us is its ability to regulate voltage. When we get into the workings of the alternator, you’ll understand why this function matters.
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If the car battery is like a phone battery then the alternator is the wall socket. The alternator is a dynamo system that uses the rotational force delivered by the serpentine belt to create an electrical current.
With old alternators, the amount of power produced depended on the RPM – the faster the serpentine belt moves, the more power the alternator produces.
Modern alternators are far more efficient and can almost deliver enough power on demand. It senses the voltage of the battery and adjusts the amount of voltage it delivers. The battery receives the charge, but also regulates it to deliver the 12.6 Volts to the vehicle.
Even though the alternator takes over from the battery as the main source of electric power, that doesn’t mean that the battery is unnecessary from this point on.
Stable voltage is extremely important for all electrical components, and it’s the battery’s job to regulate it and keep it consistent.
If you were to disconnect the battery while the car is running, the alternator will continue to supply the engine with electric power. However, it’d assume that the battery is completely dead and will work at maximum capacity to recharge it.
Without the battery to regulate the voltage going to the electric components, the high voltage may cause overheating, premature wear, failure, and even fire.
In almost every case, it’s better to drive with a dead, jump-started battery than without one.
We’ve all found ourselves in situations where the car battery died and we need to get somewhere on time.
Fortunately, there are a few ways you can get the car going:
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The jumper cables are a quick and effective way to start a car that has a dead battery. Besides the cables, you just need another car to connect the cables to – a friend, neighbor, or a stranger driving by will do.
The steps to jump-start a car are:
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The battery booster is like a jump start without the second vehicle. It makes the process much quicker and easier.
The only downside is the more expensive cost of a battery booster over jumper cables, but if you’re willing to make the investment, it’s going to pay off in the long run.
To use the battery booster, simply connect it to the battery, positive terminal first. Crank the car, leave it to idle, and disconnect the booster, negative terminal first. It’s as simple as that!
Push starting a car can only be done with a manual transmission and it requires a lot of physical effort. I’ve started smaller cars myself, but anything bigger than a subcompact needs one extra person to exclusively push with more than one being preferable.
To push start a car, you’ll need to follow these steps:
Push starting can be frustrating and you’ll certainly break a sweat. It’s difficult to get the speed up to high enough for the car to start in second, and a slight mistake with the pedal work can get it to stall out.
When I have to push start my car, I open the driver’s door and push the car myself. The gear shifter is in neutral, so when the car reaches a solid speed, I jump in, apply the clutch, set in second, and lift off the clutch.
Push starting doesn’t always work and only with practice and a feel for your car will you be able to do it with a dose of consistency.
The battery is the most needed when the car is starting, and it has to deliver a significant load to the starter for it to crank the engine.
When you start an engine with a good battery, it’ll start on ‘half a key’ meaning it’ll start as soon as you turn the key.
However, when the battery starts to give up, it’ll take longer for the car to start, followed by the weak whining from the starter. Even an inexperienced driver will be able to tell that there’s just a lack of power under the hood.
Contrary to popular belief, flickering headlights, distorted radio sounds, bad dashboard readings, and ultimately engine shutdown are not caused by a bad battery, at least not directly.
Yes, all of these occur because the battery is losing charge, but this shouldn’t happen to begin with. The real culprit is the dead alternator which is not providing power to the electric consumers, so the car uses up the battery until it dies.
The best way to avoid having to deal with a dead battery is to keep it properly maintained. There are a few things you can do to help extend the life of your battery and prevent it from dying prematurely.
There are three main factors that can reduce the lifespan of your battery – avoid them, and it’s guaranteed to last longer.
The first is frequent short trips. I’m talking about ~1-mile drives and stops, something a pizza delivery car would do.
When you’re driving like this, the battery is depleting more than the alternator is charging it, which will eventually lead to a drained battery, which is the second issue to avoid.
Whether it’s through constant starts & stops, leaving the headlights or radio on when you park the car, or through a power parasite in the system, draining the battery is never a good thing.
Draining the battery once or twice is not going to leave an impact, but if you drain it frequently it will permanently reduce its effectiveness and lifespan.
The battery overcharge happens when the alternator goes bad. It will send too much power to the battery, which may lead to a reduced lifespan.
In the more serious cases, the overcharge leads to battery overheating, dying or even craking. Test the voltage over the battery with the car running idle to see whether the alternator is overcharging.
There are a few common battery problems that you might encounter and their solutions are as follows:
Even though there’s no real risk of harm if you connect the battery cables in the wrong order, it can cause sparks.
These sparks can be potentially dangerous if the battery is leaking or there are gasoline fumes still present within the engine bay. That’s why we always apply the cables in the right order.
Every car manufacturer provides a range of batteries suitable for their vehicles. The 3 main factors are the ampere-hour rating, cold craking amps, and the battery size.
You also need to consider the terminal positions – if your car has the positive cable on the right, the positive terminal of the new battery must also face right.
Most batteries need to be replaced every three to five years. However, this can vary depending on the type of battery, how often you use your car, and how well you maintain it.
Generally, the point where you know that the battery needs to be replaced is when the car is becoming more difficult to start, and even recharging the battery back to full doesn’t last long.
Yes, you can replace the battery by yourself, as long as you’re able to lift and maneuver such a heavy object without damaging someting.
Despite their compact looks, the high amount of lead stored within batteries makes them extremely heavy. As far as the installation goes, all you need to do is position it in the right place, secure it, and install the power cables.
A car can run without a battery, but it’s very dangerous for the electrical components. Even driving with a bad or dead battery is better than driving without one, so don’t pull it out of the vehicle unless you really have to.
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