Most battery chargers on the market have a single use – charging your battery. But not the CTEK CS Free. It’s a 4-in-1 portable battery charger, maintainer, adaptive booster, and power bank. Making it the current Swiss army knife of battery tech from one of the industry leaders. With its versatile design, the CTEK CS Free meets a variety of charging needs, ensuring your battery stays in peak condition. In addition to its multifunctionality, the CTEK PRO25S battery charger features advanced safety mechanisms that protect against overcharging and reverse polarity, giving users peace of mind. Ideal for both casual users and automotive enthusiasts, this charger proves to be an indispensable tool in any garage.
CTEK CS Free what is it?
The CTEK CS Free is an intelligent jump-start pack, first and foremost. Unlike most battery-powered jump starters that simply hit the battery (and your vehicles electronics) with enough power to bring it to life, the CTEK CS Free gently raises the voltage in your battery to the point where you can start your car.
It needs around 15 minutes to do this, so it won’t ever be as quick as a regular jump starter, but it also won’t fry any sensitive ECUs in the process – a real possibility with other packs.
It can also be used as a standard CTEK battery charger, topping up your battery to keep it in the best health – ideal if your garage doesn’t have any power.
Equally, you can leave the CTEK CS Free plugged into the wall just like a CTEK CS One. It will then sit there maintaining your car battery in optimum health.
Last but not least, it has USB-C and USB-A so that it can be used as a power bank to charge your phone or run your laptop from it.
How?
Inside the CTEK CS Free is a 66Wh polymer lithium-ion battery, equivalent to 5945 mAh. The unit is the same shape as the CTEK CS One but a lot deeper to hold all the extra tech and battery. It measures 248 mm long, 98 mm wide, and 78 mm high and weighs 1.4 kg.
It works with 12V batteries only, from 10 to 130 Ah. The type doesn’t matter as it will charge WET, MF, Ca/Ca, AGM, EFB, GEL, and LiFePO₄ – handy as not many chargers work with newer LiFePO batteries.
There’s a 2-meter detachable cable with crocodile clamps on the end and a 1m mains charging cable, which is USB-C, also detachable. You get a mains power adapter with all the socket types that clip in, so you can use it anywhere in the world.
The whole thing is IP54 which means there’s limited protection from dust and but water sprays from any direction are fine – although I wouldn’t want to leave it out in the rain exposed. Just in case.
On the leading edge, there’s a USB-C and USB-A output. The right side has the crocodile clamp connection socket, and the left side is the USB-C charging input.
USB-A can provide up to 12W max for fast charging, while USB-C provides up to 60W for laptop charging.
On the top is a segmented LED display, and next to it, a power button with a lit segment to show the pack’s charge.
What’s the CTEK CS Free like?
As with all the new CTEK products, it’s ridiculously easy to use. The small button on the right-hand side turns the pack on, with the main larger segment also lighting up initially. Now the pack is on, and you can do with it as you please, use it as a power bank, or attach it to your car battery.
The main test for the CTEK CS Free was to charge one of our cars in storage. It’s in a garage with no power, so usually, I’ll disconnect the battery, bring it home, and charge it up every few months. No need anymore.
Ensuring the CTEK CS Free was fully charged, I drove to the garage and hooked up the crocodile clips. The segmented display showed that the battery had enough voltage to start with the ‘START’ segment lighting up straight away, then the second >8 segment lit up, showing it would take over 8 hours to fully charge the battery.
So I left it and came back the next day.
Testing it with a multi-meter, the battery was now at a happy 12.5 V, so it was fully charged or thereabouts.
While the pack is a little hefty, it feels solid and well-made. On the rear is the bespoke CTEK wall mount adapter, an optional extra, but worth it if you’re going to use it as a battery maintainer. Rubber pads on the feet stop it from marking whatever you rest it on.
There’s no rubbery type sleeve or bumper case as you can purchase for the CTEK CS One. It would be a nice option, seeing as the CTEK CS Free is a ‘go-anywhere’ type of device. You can purchase an optional carry case…which is pretty eye-watering in price, but I’m sure cheaper alternatives can be found.
The other noteworthy accessories are the Solar Panel Charge kit. Although its RRP is £320, it can be hooked up to the CS Free to trickle charge your vehicle no matter where you are. They’re waterproof, weather resistant, and can recharge the CS Free in around an hour. So you could use it as the perfect solution to keep AGM leisure batteries topped up.
And the USB-C Charge Cable 12V Plug charges the CS Free from your 12v cigarette lighter, but you could probably just use a generic 12v USB-C charger to do the same job.
CTEK CS Free Review Conclusion
Ease of use is key when it comes to consumer tech, and the CS Free can’t get much easier. There are no modes to select, and no Bluetooth apps are required. Just power it on, connect, and forget it.
The battery in the CS Free will remain charged for up to a year, so it’s perfect for keeping in the boot of your car for emergency battery charging on the go (phone or car). And with a two-year warranty, you’ve got extra piece of mind. But CTEK is renowned for its quality, so it’s doubtful you’ll need the warranty.
It’s a shame it doesn’t come with a rubbery bumper case or bag as standard, but that’s the only real complaint.
