Which is the best ctek smart battery chargers (uk 2026) in the UK? CTEK MXS 5.0 — The default workshop charger
There's a reason every decent independent garage has a row of CTEK chargers hanging on the wall. They don't cook batteries, they don't quit on a deeply discharged AGM, and they keep modern stop-start electrical systems alive while you're swapping a battery. After 32 years of charging everything from MGB 6-volts to 24V plant batteries, this is the line-up that earns its money.
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Quick answer — which CTEK charger should I buy?
For everyday car and small van batteries (1.2–110Ah), the CTEK MXS 5.0 is the one most people need. For larger 4x4, van and motorhome batteries (8–225Ah), go for the CTEK MXS 10. If you run lithium batteries in a campervan or a lithium starter pack, you need the CTEK Lithium XS — a normal charger isn't right for lithium. Multi-car homes, classic owners and anyone swapping batteries regularly should look at the CTEK PRO25S. Bob's pick for a normal family car: the MXS 5.0.
Why CTEK over a supermarket charger
A cheap trickle charger has one mode: dumb constant voltage. Leave one on a healthy battery for a week and you'll boil the electrolyte off; leave it on a deeply discharged AGM and it'll never wake up. CTEK chargers run an 8-step automatic programme — desulphation, soft-start, bulk, absorption, analysis, recondition, float and pulse maintenance. That's the difference between a battery that lasts five years and one you're replacing every two.
Matching the model to the battery
MXS 5.0 covers the everyday car-and-van bracket (1.2–110Ah). MXS 10 steps up for bigger 4x4, van and motorhome batteries (8–225Ah) and recovers them faster. The PRO25S is the workshop unit — 25A output, full supply mode for diagnostics, parallel charging. For a classic with a 6V battery, the MXS 5.0 covers both 6V and 12V at the flick of a switch.
AGM, EFB and lithium — does it matter?
Modern stop-start cars run AGM or EFB batteries — they need a slightly higher absorption voltage than flooded lead-acid, and a wrong charger will undercharge them for years until they fail prematurely. Every CTEK from MXS 5.0 upwards has a dedicated AGM mode. Lithium support (LiFePO4) is on the Lithium XS and PRO25S — don't put a lithium battery on a charger without it.
Supply mode — the killer feature for modern cars
Disconnect a battery on a 2015+ car and you lose radio codes, sat-nav presets, sometimes throttle adaptations. Supply mode on the MXS 10 and PRO25S puts a steady 13.6V across the car's electrical system while you physically swap the battery — no lost settings, no relearns. We use it daily.
Recond mode — when to use it, when to leave it alone
Recond pulses higher voltage at a sulphated battery to break crystal build-up. It works on tired flooded batteries that have been left flat. It can also kill a healthy AGM if used carelessly. Rule of thumb: only use recond once, on a battery that's measurably weak. If it doesn't come back, it's done.
Top picks
- CTEK MXS 5.0 — The default workshop charger
- CTEK MXS 10 — Pro pick for vans & motorhomes
- CTEK PRO25S — Workshop-grade — what indie garages actually use
- CTEK Lithium XS — Best for LiFePO4 leisure batteries
FAQs
Can a CTEK stay connected permanently?
Yes — every CTEK from MXS 5.0 up has a pulse-maintenance final stage designed for indefinite connection. Ideal for classics, motorhomes or seasonally stored cars.
Will it hurt my stop-start AGM battery?
Not if you select AGM mode — it adjusts absorption voltage for the higher charge acceptance these batteries need. Using standard mode long-term will undercharge them.
MXS 5.0 or MXS 10 for a 70Ah van battery?
Either works, but the MXS 10 will recover a discharged battery in half the time and gives you supply mode for battery swaps. If it's a daily-use van, the MXS 10 pays back fast.