We all know now, with the world being locked down, that driving isnât something thatâs as often done as it was before. Cars are meant to be driven around, and for their many parts to get sweaty every now and then. Letting it sit for a long time can have horrid unintended consequences, and one of them being the carâs battery. While youâre Netflix-ing and chilling, the battery could very well die. This then prompts you to wonder, and ask as to how long does it take to charge a car battery?
Of course, youâd ask this question first, knowing that the alternative fixes require more elbow grease. You might not have someone readily available to jump-start your car with. Nor, would you want to shell out and buy a whole new battery. This is common enough of a problem under usual circumstances, and more so during the lockdown hibernation. So much so, that newspaper ads are actively being taken out to remind people to check their batteries once lockdown is over.
So, how long does it take to charge a car battery? Why did my battery go flat in the first place? What do I need to do to have my car running again? Loads of questions, and ones that weâll answer one by one, step by step in our guide. And worry not, as often times your car battery going flat could be a very simple thing to fix. Most of what is required is a small investment of money, time, and energy. So, come along and have a read before making an appointment to buy a whole new battery.
- Causes of a dead battery
- Can you charge it?
- Types of chargers
- How long does it take?
- Prevention
- Conclusion
What Is Causing My Carâs Battery To Go Flat?
I know, youâre probably itching to know more about how long does it take to charge a car battery. But before we can go into discussing that, weâll first need to understand more about the reasons behind your carâs battery going flat. The battery, after all, is a key component in any car. In the context of internal combustion engine cars, the battery is the primary source of power for all your carâs electrics. This includes the actual starting of your car itself, sparking it into life.
A spark of electricity is needed to begin the combustion process, which makes your car go. Then, your carâs electrics need juice from the battery. This includes all your carâs lights, the windshield wipers, or the carâs internal computer brain with its many sensors. Then, there are the little miscellaneous functions like running the cigarette lighter, or the carâs USB ports. This highlights then, the importance of what a battery does, and why it matters to keep it in good condition.
Ordinarily, your carâs battery is always kept charged while the car is running. Once the engineâs started, it will also power the alternator, which then charges the battery along. Naturally, lockdowns have meant that we couldnât drive often enough to charge our carâs batteries. But even when everythingâs turned off, your carâs battery will indeed keep on draining. Because even while your car is asleep, the battery is needed to power functions such as your carâs alarm.
Before we get into discussing more on how long does it take to charge a car battery, here are some of the most common causes for flat batteries, even when your car is turned off.
1. Leaving the lights on
As weâve mentioned earlier, leaving your carâs lights to keep running while the engine is turned off can cause battery drain. This is most often a fairly innocent mistake. Maybe itâs in the middle of the day, and youâve accidentally bumped onto the light switch. Naturally, it would be hard to tell if the lights were even on, with a lot of sunlight outside. Or, you mightâve done this intentionally, wanting to keep the lights on to do something, or see in the dark.
Say youâve parked in a dark alley, and need some illumination to grab stuff from your car. Leaving the head-, and tail-lights on would make seeing things a lot easier. For brief periods of time, this is often fine. Plus, your carâs alternators would recharge your battery the next time you take it for a drive. However, do this for an extended period, and it will drain your battery. Thankfully, most modern cars would warn you if youâve left the lights on with the engine off.
2. Parasitic drains within the car
This is also another extension from leaving your carâs lights on, which can cause your battery to run flat. âParasiticâ drains or draws can be common enough in a lot of cars. We talked about how batteries will naturally drain over time, even when your carâs engine is turned off. This is to keep the carâs electrical and electronic functions to run, even when itâs sitting idle. Additionally, it could maintain your carâs alarm, keyless entry, internal clocks, and so on. Small drains like these are often normal.
What isnât normal, are electrics turning on when they shouldnât be. This is what is known as parasitic drains. They are minor electrical draws that donât occur normally. Sometimes, this can be accidental. For instance, accidentally leaving the glove box or trunk open or not fully closed would keep their lights on. Other times, this can be down to faulty electrics. Problems such as bad fuses, or bad wiring can cause things like your carâs interior lighting to come on, when they shouldnât.
3. Alternator not charging your carâs battery
Another cause of a drained battery is down to a faulty alternator. We learned earlier that your carâs battery is always recharged while driving, or by keeping the engine running. This helps to drive the alternator, which is in essence, a generator that keeps your battery juiced up. Think of this as needing to keep pedalling on your exercise bike to keep the display running. However, a carâs alternator can fail over time, either due to poor maintenance, or wear and tear.
This will mean that your battery canât get recharged. This can happen while driving. Youâll either be met by your car suddenly switching off while driving, or by waking up to a car that wonât even start. There are some clear symptoms that you could look out for to know if your alternator is starting to see signs of failure. The more common warning is through the âcheck engine lightâ on your dash. Otherwise, notice any weird behaviours like difficulty starting, or burning smell from the engine bay.
4. Taking too many short drives
We know now that you can recharge your carâs battery just by driving, or keeping the engine running. The alternator is a godsend, in this regard. However, know that the alternator will always require some time before it can fully charge up your carâs battery. This will depend on your specific car, and the condition of its battery. But in all, it certainly canât top-up your battery in an instant. In fact, itâs those short drives or engine start-ups that can be detrimental to your batteryâs health.
You might think firing up your carâs engine for five minutes is enough. Or, maybe youâd take your car around your apartmentâs parking garage in a circle, and think itâs sufficient to charge up the battery. But in actuality, this is actually causing it to drain the battery even more. A carâs battery undergoes a lot of usage and strain while starting up. It needs to help spark the engine to life, while also turning on all your carâs electronics and electrics.
As such, the power draw is immense while your car is in the process of âbooting upâ. However, this electrical usage is negligible if youâre taking it out for a long drive, such as going to work. This should be more than enough time for the alternator to work optimally, and charge your battery as needed. Turning your engine on, and then leaving the alternator to charge up for just a few minutes is not enough to top-up the battery. Doing so is a net loss for your carâs overall battery capacity.
5. Excess of heat, or cold temperatures
One thing weâve learned in the era of electric cars, is that temperature can have a big impact on a batteryâs characteristics. This is owing to the chemical and material compounds inside of the battery itself. This can, for instance, cause the lead sulphate to crystallise. Something as simple as too much heat, or cold could affect the batteryâs overall performance and capacity. This goes both ways with internal combustion cars, as well as electric cars.
Newer types, or more well-maintained batteries should be able to resist against extreme changes in temperature. However, older cars or batteries wonât share the same robustness. So, do take note of how youâre storing your car. For example, keeping your car on the driveway while itâs snowing or cold outside could cause a more pronounced battery drain. Even worse, temperature changes can also make it so that the battery takes more time needed to charge.
6. Faulty, loose, or corroded battery connectors
The battery is connected through the positive and negative terminals, which are then attached to the rest of the car. It functions both ways, sending electricity to the rest of your car, and also getting topped up from the alternator. Therefore, it is important in making sure your batteryâs connections are all well and good. But often times, regular driving can cause wear and tear. For instance, all the vibrations and jostling around could knock the cables loose.
This would hamper both the electrical supply, and also impacts how much your battery is charged up from the alternator. It could even cause long-term damage to other electrical parts of the car. Maybe, those cables have become damaged, due to short-circuiting or excess heat from the engine. Alternatively, the terminals could become corroded over time, from being exposed to moisture. Corrosion on the terminals will impact the batteryâs connections.
7. Worn out, or weak battery
A battery, just like many other parts of a car, would eventually wear out and need replacing. This is normal, and its lifespan will depend on how youâve driven your car, and how youâve maintained it. The causes weâve mentioned above could not only cause battery drain, but also prematurely wear out your battery. Things such as letting your electrics keep running, poor charging from the alternator, or taking too many short drives can cause long term wear.
Often times, a carâs battery will easily last five years. However, youâre often recommended to replace it every three to four years of regular driving. Take good care of it, and it could happily run for more than that. If the battery has gotten too old or weak, it will not be able to hold a full charge well. That could, for instance, cause it to drain much faster and die very quickly. Even the smallest parasitic drains, such as your car alarm running, could very well kill an old, or weak battery.
How Long Does It Take To Charge A Car Battery â Can I Charge It?
You may now be able to understand more as to why your carâs battery is dead. Youâre content in knowing that it may or may not be your fault. But still, things need to be done, and youâre going to have to drive it eventually. But not so fast. Before we need to know how long does it take to charge a car battery, youâll first need to know if you can even charge it. Would a quick jump-start from another carâs battery suffice, or would you need to buy a completely new battery?
These are all valid questions, and knowing which approach to take first is important. People often think of jump-starting a car as the best possible solution. After all, itâs easy enough to do, provided you have the jumper cables and a fellow car owner willing to lend you their battery. Or, consider a portable jump-starter. However, know that jump-starting a car can cause added strain to both the battery itself, and the alternator. This is since youâll be needing to start up your car to recharge the battery.
Jump-Start vs. Battery Charger vs. Full Replacement
By doing so, the alternator has to work double-time. Itâll need to both help channel electricity to the dead battery, while also working for 15 minutes or so to continually recharge it. Jump-starting a car will no doubt be worthwhile in an emergency, but it can lead to your alternator wearing out over time. The full cost of an alternator replacement is far higher than needing to replace your battery. Therefore, jump-starting a battery should be something you save only for an emergency.
On the flip side, and as mentioned earlier, a carâs battery will need replacing at some point or another. Eventually, its usable capacity will decrease, and then become insufficient in maintaining the functions of the car. There are some signs that you could tell if your battery is about to fail, and is in need of a replacement. For instance, your car might be slow to start, or âcoughâ as youâre turning the key. Your car might backfire, or you can notice the headlights running a bit dim.
If you notice any of those symptoms above, then your only choice would be needing to replace the entire battery. Finally, we get to a battery charger. This is the best way for maintaining your car batteryâs charge, and without causing long term damage. This is less straining on your car than a jump-start, and is certainly a far smaller investment than needing a full replacement. The only thing that it needs from you is a small expense in time, as it slowly charges up your carâs battery.
How Long Does It Take To Charge A Car Battery â Types Of Battery Chargers
The most natural question before asking as to how long does it take to charge a car battery, would be, âHow do I even charge it in the first place?â Before we dive straight in, weâll first need to know what kind of battery charger youâll be needing. This will, of course, be contingent on a number of variables. The most important of which is knowing what type of car battery you have. Typically, most cars have 12-volt lead-acid batteries, which should work easily with any type of charger.
You should also pay heed to the size of your batteryâs capacity, and its condition before going any further into buying a battery charger. There are three common types of car battery chargers. There are linear, multi-stage, and trickle chargers. Each has its uses, along with their respective benefits and downsides. For our guide here, weâll be taking a look at them with a bit more detail. Weâll also see how they stack up, in regards to how long they each take for a full charge.
1. Linear battery charger
This is the cheapest, and simplest way to charge up your carâs battery. Linear battery chargers can be found quite affordably, costing as little as $20 or $30 for most brands. Theyâre also very convenient to operate, as it requires you to plug it into any household wall outlet. From there, it will charge up your carâs battery. However, its relatively low cost and ease does have some drawbacks. For one, linear battery chargers can only operate with low amperage.
What this means, is that itâll take longer for your carâs battery to charge up to nominal levels. On average, you could be waiting for around 14 hours or more for a full charge, depending on the amperage. Cheaper linear chargers operate around 2-3 amperes (amps per hour). Another disadvantage is that linear battery chargers are quite literally âlinearâ in their operation. They continually charge up your battery at a set amperage, and thereâs no controller or additional setting to control that.
This results in a linear battery charger not knowing when to stop charging. Leaving it to overcharge your carâs battery could cause your already poorly battery to fail, or worse, explode. As such, we only recommend linear battery chargers to those that have the patience to monitor their progress, and ensure that your carâs battery isnât being overcharged. Moreover, a linear battery charger is only suggested if you have the time to wait around 12 or so hours for a complete cycle.
2. Multi-stage charger
Multi-stage chargers are far more complex, and featureful compared to a more simple linear battery charger. The big downside, is that multi-stage battery chargers are far more expensive. Most often, youâll find them on sale for around $100. But for the most part, the drawbacks end there. As their name suggests, a multi-stage battery charger can operate in multiple different stages while charging.
This has lead them to be called âsmartâ, or âintelligentâ chargers. What this means, is that multi-stage chargers recharge your carâs battery in bursts of electrical current. This is in contrast to a continuous stream of current being channelled, like the ones with a linear battery charger. The benefit here, is that charging like this is much better for your batteryâs wellbeing in the long term, compared to a linear and continuous charge.
Moreover, multi-stage battery chargers offer charging at much higher max amperages compared to the average linear charger. Among the more complex ones, a multi-stage charger can offer an amperage of up to 12 amperes (12 amp per hour). This, in turn, could see your carâs battery charged up from nearly dead in as little as 5 or so minutes. At most, youâll be waiting under 9 hour to fully charge a very large battery. Some of the more expensive ones even have displays, and gauges to let you control the amperage as needed.
3. Trickle charger
The last type of car battery charger is the trickle charger. It works very differently compared to both the linear, and multi-stage battery chargers. Those two can at the very least charge up a carâs battery from dead, differentiated mostly by how long theyâd take. However, a trickle charger most often isnât used for charging up a battery from dead. Instead, they are often used to prevent a carâs battery from being drained completely in the first place.
Trickle chargers operate at very low amperages, even compared to the cheaper linear chargers. As the name suggests, trickle chargers will only require tiny trickles of electrical current, often between 0.8 to 2 amperes. As such, it can take up to 2 days for a charge. When your car is not being used for a long time, attaching it to a trickle charger would let the battery charge based on the amount that is needed. This is to ensure that the battery remains at its nominal capacity at all times. This is mostly used for storing cars and maintaining the battery at the same time.
So, How Long Does It Take To Charge A Car Battery?
At this point, you might have some rough idea of how long it will take for your carâs battery to charge up using a battery charger. But, there are loads of different chargers on sale in the market today. They can all be classed as per our examples earlier. So, how would I know more precisely as to how long does it take to charge a car battery from dead? To make things easier, weâre going to give you some scenarios.
Firstly, we need a baseline to make our maths a bit easier. Most cars will usually have a 12-volt lead-acid battery, and a full capacity of around 60Ah (amperes). This is right around the average, although some cars might have 80 or larger ampere capacity batteries. More commercial vehicles, such as vans or trucks almost always have bigger batteries. Now, weâll consider the fact on average, car batteries can take in upto 12 ampere-per-hour.
This way, we have to key numbers â 60Ah total capacity, and an intake charge of upto 12 ampere-per-hour. We can then do simple maths depending on the amperage of your new battery charger. For instance, a linear charger with an average amperage of 6A would require around 10 hours to charge up your car. Meanwhile, a trickle charger that sends around 1A might need a full 60 hours for a charge. Multi-stage chargers with a max output 12A could have it done in around 5 hours.
So you need to find the Ah rating on your battery (possibly between 50Ah â 110Ah), then look at your charger and find the max charging rate (6 Amps as an example). Then divide the total capacity of the battery by the rating of your charger to find out how long it could take to charge.
Charing Formula
Total battery capacity/charging power = Time taken to charge
Charging Example
60 (Ah) / 6 amps (max amps per hours)Â = 10 Hours
How Long Does It Take To Charge A Car Battery â Prevention
Letâs say at this stage, youâve already charged up your carâs battery, and have taken your motor out for a drive. Surely, youâll be relieved, but you might be curious to know how to prevent your car from draining its battery again. There are, thankfully, a lot of ways you can make sure your carâs battery always stays full. For a start, make sure youâre attentive after having the engine turned off. Make sure all the lights, and electronics are properly switched off before parking it in for the night.
The next step would be taking out your car for a drive every once in a while. Normally, a carâs battery can more or less last without driving it for around a week or two. However, we would definitely not recommend leaving any vehicle sitting idle for this long. Try and take it out for a proper spin at the very least once in a week. Understandably, this can be hard in our newly locked down lifestyles. However, do try to responsibly find a quiet place to roam around, if you can.
Even if itâs just driving it in circles around the neighbourhood block, or around your apartmentâs parking bay. And, be sure to take it out for a proper drive. Donât just start up your car for five minutes, thinking itâs enough. Have it driven for some reasonable distance, and at least for 15 minutes. If this isnât an option, then consider safely disconnecting the battery from the car altogether to avoid those small current drains. Or, think of getting yourself a trickle charger.
How Long Does It Take To Charge A Car Battery â Conclusion
That now concludes our guide on how long does it take to charge a car battery. We hope weâve been of some assistance in letting you know how much time is needed to charge up a carâs battery. We also hope youâre now more aware of whatâs causing your carâs battery to keep discharging, and how to prevent it. Itâs safe to say that especially now within quarantine, this will be a common enough problem. Once lockdowns are lifted, weâll be expecting more and more dead batteries.
Conclusively, the best way to prevent your carâs battery from going flat in the first place is just to drive it. In fact, never leave your car sitting still for any extended periods of time. Everything in a car is best kept at its most optimal state while driving. Fluids need to swish, mechanicals need to lubricate, electricals need to run, and batteries need to charge.
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