CTEK CS FREE 12V 20A Portable Smart Battery Charger Maintainer Lead Acid Lithium

Risk-Free 14 Day Returns

If you change your mind, return it to us within 14 days of the date you received it, no questions asked.
T&Cs apply

Just charge up CS FREE’s internal battery and keep it with you wherever you go, and it’ll stay fully charged for up to a year. CS FREE features our revolutionary Adaptive Boost technology to quickly get you going from a flat battery. CS FREE automatically analyses the state of your battery and adjusts to the battery’s voltage level. It then works out the safest and quickest way to give your battery the power it needs to start your vehicle within 15 minutes. CS FREE works anywhere and can even be powered by solar or a 12V battery for longer term maintenance charging.

The CS FREE is the world’s first fully portable battery charger and maintainer with Adaptive Boost to get your flat battery going quickly and safely – without the need for mains power. In other words, it’s a 12V power bank for your vehicle that works with both lead-acid and lithium (12V LiFePO4) batteries. Plus, it’ll keep your portable tech, like phones, laptops & cameras topped up too. So simply charge it up, take it with you and use it anywhere! 


The CS FREE is a portable Adaptive Booster that will get you going from a flat battery within 15 minutes.


Just charge up the CS FREE’s internal battery and you’ve got a 12V power bank that will stay fully charged until you need it – for up to a year. And with USB-C connectivity, you can fully recharge your CS FREE in just one hour!


If you have a car, a motorcycle, a boat or any other 12V vehicle and want to charge and maintain for longer periods of time…well no worries! We some optional handy accessories to enable charging via solar panel or a 12V service battery.


  • Brand: CTEK
  • Model: CS FREE
  • Battery Capacity: 10-130 Ah
  • Battery Capacity CEC-400: 10-130 Ah
  • Changing Category: AC Charging; DC Charging
  • Battery Voltage: 12V
  • Battery Chemistry: Lead Acid; Lithium-ion
  • Ambient Storage Temperature: -20 °C to +45 °C (-4 °F to +113 °F)
  • Ambient Operating Temperature: -20 ËšC to +50 ËšC (- 4 °F to +122 °F)
  • Cooling: Natural Convection
  • Frequency: 50-60 Hz
  • Input: USB-C, 5 VDC – 25 VDC, 3 ADC/60 W max
  • Output: 12 V, 20 A/240 W max
  • Battery types: 12 V:; WET; MF; Ca/Ca; AGM; EFB; GEL; LiFePOâ‚„
  • Rated voltage (Input): 100 VAC – 240 VAC
  • Degree of protection: IP54
  • Enclosure material: Plastic
  • User interface: LED symbols
  • Detachable charging cable length (output): 2m
  • Internal battery capacity: 66 Wh
  • Internal battery cell chemistry: Polymer Lithium-Ion
  • Internal battery cell type: Pouch Cell
  • Internal battery charge temperature: 0ËšC to +45ËšC (32ËšF to 113ËšF)
  • Internal battery discharge temperature: -20 ËšC to +50 ËšC (- 4 °F to +122 °F)
  • Internal battery lifespan: 300 cycles, 80%
  • Internal battery shelf life: 1 year
  • Internal battery weight: 0.5 kg
  • Mains adapter cable length: 1m
  • Mains adapter cable type: USB-C


  • 1 x CTEK CS FREE
  • User Manual is accessible online


  • Product Dimensions (W x L x H): 98 x 248 x 78mm
  • Product Weight: 1.4kg

SKU: CTEK-40-462

We accept Change of Mind returns for 14 days after you have received the item in cases where you have changed your mind or made an incorrect purchase and wish to return the product. This also applies to orders cancelled when the item has already been dispatched from our warehouse. The item must be in a re-saleable condition to qualify for a change of mind refund. Deductions may apply including Initial and Return Shipping, as well as restocking fee of 10% of the product price


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