12v laptop car charger – powering my laptop without an inverter

I use my laptop a lot, for work, editing photos, internet and most often for producing music. For this reason, I need a reliable laptop charger in my van. Something I can use daily that doesn’t kill the van’s leisure batteries.

I also wanted a laptop charger that runs without the use of my inverter, so needed one that runs directly off 12V, using the cigarette lighter socket. I certainly can use my 1000W inverter, and plug my original laptop charger into it, but this is overkill and not very energy efficient, so I started looking into powering a laptop from a car battery (or leisure batteries in my case).

My requirements were:

• 12V to 19V laptop charger (for my Acer Aspire laptop)
• Plugs directly into a cigarette lighter socket (I have multiple in my van)
• Energy efficient
• But still powerful enough to charge my laptop quickly
• Quality – it needed to power my laptop without it interfering with my audio equipment

I started digging, reading many forums, and even learning about DC-DC converters to get a better understanding what it was that I needed. After a lot of research, I found a Universal 12V laptop charger (Amazon).

This charger certainly seemed like it fit the bill. It looked well built, had 90W of power output (more than enough for most laptops), plugs straight into a cigarette lighter socket and even has 2 USB sockets to power tablets, phones or whatever other 5V USB device you might have. So I took the plunge and bought it off Amazon.

I’ve had it for a couple of months now, and use it every single day. I must say that I’m very impressed. I can now power my laptop straight from my leisure batteries without the use of my inverter, which is more energy efficient and a lot more convenient.

A note about inverters: 

Inverters change 12V DC to 220vAC (110V in some countries), and do this in one of two ways. 1 is modified sine wave (MSW), which is not the same as mains power in your home, and 2 is pure sine wave (PSW) which is the ‘clean’ type of AC power, similar to what you have at home. 

Unfortunately, the cheap inverters are almost always modified sine wave inverters, and this is a problem when it comes to laptops. In some cases, a cheap MSW inverter will cause your laptop screen to flicker when plugged in, which pretty much renders your laptop useless, so these aren’t a practical solution for laptops. 

A pure sine wave inverter works just fine with laptops, but even so, inverters aren’t very efficient for charging laptops. An inverter steps up your 12V to 220V (or 110V), and then the laptop charger will step the power back down to  18.5V, 19V, 20V etc. depending on your laptop.

In each of these steps, there’s a power loss. Also, if you leave your inverter switched on, even when it’s not charging your laptop, it is still draining power from your battery.

So even though I have a 1000W pure sine inverter in my van, still wanted something that was efficient (and convenient) for charging my laptop.

Let’s take a look at the 12v laptop charger that I have:

This charger comes with 14 ‘tips’ and a data sheet to help you locate the correct connection and voltage for your device. All you need to do is find the voltage and current on your original charger, and cross reference this along with your laptop’s brand to the data sheet. Once you have the correct tip, connect it to the end of the cable and plug in.

Technical info

Input: 11V DC – 15V DC
Output: 18.5V/ 19V/ 19.5/ 20V DC
USB output: 5V 2.1A, 5V 1A

Tip details and compatible brands:

Tip	Voltage & Current	Size	Compatible Brands
M1	15V, 4A/5A/6A	6.3*3.0mm	TOSHIBA
M3	16V, 4A	6.5*4.5*1.35mm	SONY, FUJITSU
M4	18.5V, 3.5A/4.9A	4.8*1.7mm	HP
M5	19V, 2.37A/3.42A/4.74A	5.5*2.5mm	TOSHIBA, ASUS
M6	19V, 3.16A/4.74A	5.0*3.0mm with pin	SAMSUNG
M8	19.5V, 2A/3.9A/4.7A	6.5*4.4mm with pin	SONY
M9	19.5V, 3.34A/4.62A	7.4*5.0mm with pin	DELL
M11	20V, 3.25A/4.5A	7.9*5.4mm with pin	LENOVO/IBM
M12	18.5V, 3.5A/4.74A	7.4*5.0mm with pin	HP
M13	1.58A/2.31A/2.37A	4.0*1.7mm	TOSHIBA
M18	19V, 2.1A/2.37A/3.42A	3.0*1.0mm	Acer, SAMSUNG, ASUS
M19	19V, 2.37A/3.42A	4.0*1.35mm	ASUS
M20	19V, 3.42A/4.74A	5.5*1.7mm	ACER, GATEWAY
M21	19.5V, 2.31A/3.33A	4.5*3.0mm with pin	HP
M22	19.5V, 2.31A/3.34A/4.62A	4.5*3.0mm with pin	DELL
M27	20V, 3.25A/4.5A	11*5.0mm Square Yellow Tip	LENOVO
M28	19.5V, 2.31A/3.33A	4.8*1.7mm with step plastic	HP

Final verdict:

This laptop charger works well for my needs. The only gripe I have is that the cable is a bit short. At 4ft, it just doesn’t reach as far as I wanted. This isn’t a major issue, and I just bought myself a cigarette lighter socket extension (Amazon) to solve this problem. If you need one of these, make sure it can handle a higher current – 10A will be plenty.

It’s worth noting that here’s also a “brick” version of this product. Although it’s bigger, in some vehicles the “plug-in” one that I have will not fit into your cigarette lighter socket, depending on where it’s located, so just keep this in mind.

All in all, I’m very happy with this charger, it’s made my life a lot easier.

I hope you enjoyed reading my review. If you have any questions, please leave a comment below. If you want to go ahead and get yourself one now, you can get the charger from Amazon right here (Amazon).

Update (9 July 2020):

Some people have asked me about Macbook car chargers, so I did some research and found a couple. The first one is the BatPower USB C car charger (for newer Macbooks that charge via USB C) which can be found here.

If you have an older Macbook that uses the magsafe charging cable, this version is perfect for that.

Note: I don’t own any of the Macbook chargers (although keen to get one), so please note that the links to Macbook chargers are for information only. They seem to have good reviews, but I can’t comment personally on them since I’ve not used them myself.