Best smart battery chargers 2021

Advancing technology means motorists need to take better care of their car batteries. These are the best smart battery chargers for new and classic cars on sale today...

Battery chargers 2021 - lead

Modern smart battery chargers are amazingly advanced pieces of kit, so much so that some people are left wondering if they really need such sophisticated (and pricey) equipment for the seemingly simple task of charging a battery.

But, as batteries have advanced in recent years, gaining bigger outputs, charging faster and holding charge for longer, so, too, have they become far less tolerant of abuse. It’s no accident that almost all smart chargers now have conditioning modes that can keep a battery topped up long term.

Battery chargers 2021 test

These are useful not only for keeping classic cars topped up, but also because modern cars – with their many computer memories and power sapping security systems – drain their batteries in a manner of weeks. Nothing ruins a modern battery quicker than being left in a low state of charge for a prolonged time. 

Better still, many chargers come with a hard-wired lead, which is attached to the battery clamps and has a charging plug – to be located somewhere convenient – on its other end. So “plugging in the car” doesn’t involve opening the bonnet or getting oily hands.

What's more, the conditioning (or maintenance) mode is just one part of a smart charger’s multi-stage cycle. Whilst some steps are simply rudimentary checks, most of the others monitor the battery’s charge level carefully and utilise different voltages to maximise the level of current safely flowing into the battery.

Having such a fine level of voltage control, as well as battery monitoring, means chargers can have custom cycles for different technologies, such as the EBC and AGM batteries used in stop-start vehicles. Reconditioning modes are another poplar feature; these use high voltage pulses to blast away the performance sapping plate coatings that are caused by excessive time at low charge levels.

Battery chargers 2021 - best of

But are these modes really necessary? Well, reconditioning mode can restore a borderline bad battery back to reliable service, providing it’s done in time. And while a charger’s automatic mode won’t damage a battery – other than with lithium batteries, which must always use a dedicated cycle – the right mode for the battery type will give a faster charge that may result in a slightly higher charge level, too.  

In this test we balance all of this wizardry against real-life factors, such as the length of the leads, their charging speed and how well the charger communicates progress, as well as value for money and any extras included. With many units safe to use on a battery that's connected to a car, and that are water sealed to the IP65 standard, it even becomes possible to position the charger in the weather-shielded confines of an engine bay – even if the car’s outside. 

Best smart battery chargers 2021

10. Clarke CB09-12

Smart battery chargers - Clarke CB09-12

Price: £71.98
Buy from: Amazon or www.machinemart.co.uk
Contact: 01992 565300
Online: www.clarkeinternational.com
Overall score: 2/5
Suitable battery capacities: 6-160Ah

It's a tribute to CTEK, below in sixth position overall, that the brand's format is so widely emulated, Clarke's 8 Amp  CB09-12 being a prime example.

Nine stage charging cycle? Check. Battery clamps and a permanently wired-on lead? Check. Dedicated modes for AGM batteries and power supply mode? Check. The list goes on.

Clarke goes one better with accessories; one lead lets you charge your battery, or maintain a vehicle’s memories during battery removal, through the cigarette lighter socket, while another allows direct connection to 12-volt accessories.

However, short mains and charge leads, a high price, non-IP65 construction, and no separate reconditioning mode all cost it points.

9. Halfords Advanced Smart Battery Charger

Smart battery charger 2021 - Halfords Advanced Smart Battery Charger

Price: £48.00
Buy from: www.halfords.com
Contact: 0330 135 9779
Online: www.halfords.com
Overall score: 3/5
Suitable battery capacities: 20-90Ah

A reasonable unit from Halfords that gets the basics right. Decent lead lengths aid positioning and connection, IP65 construction allows safe under-bonnet usage outside, a permanently wired-on lead is included, and the charger tackles severely depleted batteries right down to 3 volts.

But whilst the glossy touch-sensitive front panel looks great, we suspect its cost robs the unit of more desirable features, such as a better charge process indicator – the single LED only shows if the unit is charging or finished.

It's unusual, too, for a recently launched battery charger to have just three stages in its charging cycle.

8. Laser 7652 - BEST BUDGET BUY

Smart battery chargers 2021 - Laser 7652

Price: £44.00
Buy from: Amazon or www.thetoolacademy.com
Contact: 01926 815000
Online: www.lasertools.co.uk
Overall score: 3/5
Suitable battery capacities: 4-120Ah

Laser's 7652 pips Halfords' Advanced Smart Battery Charger as the best all rounder for less than fifty quid. Both models output up to 4 Amps, but the 7652's more sophisticated charge cycle gives faster charge times. A dedicated mode for winter operation (less than 5 deg C) also helps in this respect.

In use, although the leads are marginally shorter than we'd like, everything else is good. The case is IP65 damp sealed, and the LCD display has an intuitive mobile/tablet style charge indicator as well as showing voltage. The 6 volt mode is a bonus for classic car owners.

7. Wolf WBC180

Smart battery charger 2021 - Wolf WBC180

Price: £29.99
Buy from: Amazon or www.ukhs.tv
Contact: 0330 123 0001
Online: www.ukhs.tv
Overall score: 3/5
Suitable battery capacities: 4-120Ah

The outright cheapest model here is probably not what you'd expect. With a punchy 10 Amp max charge current, and a spookily similar LED display to Laser’s 7652, this doesn't feel at all like the poor relation.

Other similarities to the 7652 include 6 and 12 volt operation, a dedicated winter mode to maintain decent charge speeds in cold weather, and – less desirably – leads that are a smidgen shorter than ideal.

We suspect the ultra-keen price is partly because of its old-school styling and layout. The vented case rules out usage outside, and the usually de rigueur hard-wired lead isn't included.

6. CTEK CT5

Smart battery charger 2021 - CTEK CT5

Price: £79.00
Buy from: Amazon or www.halfords.com
Contact: 01488 689400
Online: www.ctek.com
Overall score: 4/5
Suitable battery capacities: 20-160Ah

CTEK has been ahead of the game for years, and it still has a few aces to play as the rest of the market catches up. The CT5‘s unprecedented user-friendliness being a good example. Charge status, for instance, is displayed as charging time left, in hours rather than volts or percentages.

Better still, there's a "Try" indicator, which illuminates when a battery amasses just enough energy to stand a chance of starting an engine – handy when time is tight.

Otherwise the CT5 is typically CTEK: well made, with fast charging, and sporting dedicated modes for AGM batteries and reconditioning.

5. Draper 53491 - RECOMMENDED

Smart Battery Chargers 2021 - Draper 53491

Price: £72.71
Buy from: Amazon or www.lawson-his.co.uk
Contact: 023 8049 4333
Online: www.drapertools.com
Overall score: 4/5
Suitable battery capacities: 4-200Ah

Draper's take on the compact charger may be bulky but we can forgive that because this brand new model offers a lot at a price that neatly undercuts market rivals like CTEK and NOCO.

Rapid, foolproof charging is achieved thanks to a thumping 10 Amp max charge current and dedicated charge cycles for winter usage, AGM, Gel, and Lithium battery technologies.

In stark contrast to that cutting edge lithium compatibility, the unit also has a 6 volt mode for use with considerably older technology.

Only its slightly short leads and the lack of a select-able reconditioning mode kept this off the top spot.

4. NOCO Genius10UK - RECOMMENDED

Smart Battery Chargers 2021 - NOCO Genius10UK - RECOMMENDED

Price: £120.00
Buy from: Amazon or www.halfords.com
Contact: 01394 604040
Online: www.no.co
Overall score: 4/5
Suitable battery capacities: up to 230Ah

NOCO’s Genius10UK has the past and the future pretty well sewn up. It’s compatible with 6 and 12 volt batteries of any kind, including lithium, and has dedicated charging cycles for both, as well as AGM and even 6 volt AGM. Factor in the 10 Amp max charging current, and this unit really is unbeatable, here, for charge speed.

It also goes beyond others when dealing with poorly batteries. It'll automatically charge batteries reduced to 1 volt of internal charge, while "force" mode attempts to charge batteries in even more dire states.

There's also a manual desulphation mode to recondition tired batteries as much as possible.

3. Ring RSC612 SmartCharge Premium Plus

Smart Chargers 2021 - Ring RSC612 SmartCharge Premium Plus

Price: £85.00
Buy from: Amazon or www.halfords.com
Contact: 0113 213 2000
Online: www.ringautomotive.co.uk
Overall score: 4/5
Suitable battery capacities: 25-300Ah

Ring's RSC612 has been around for some years now, but that's testimony to Ring getting it right from the start and the unit being incredibly cutting edge when launched. Even now, lithium is the only modern battery technology that it doesn't support.

With up to 12 amps of charging current available, and dedicated cycles for winter use and AGM batteries, rapid charging is guaranteed. More advanced users will appreciate the unit's diagnostic functions, which rate a battery's starting power and alternator performance.

Strangely, for such a sophisticated model, the unit is not sealed to IP65 standards, so must only be used indoors.

2. Sealey Schumacher SCI90S

Smart Battery Chargers 2021 - Sealey Schumacher SCI90S

Price: £165.00
Buy from: Amazon or www.ffx.co.uk
Contact: 01284 757500
Online: www.sealey.co.uk
Overall score: 4/5
Suitable battery capacities: 12-230Ah

A slightly leftfield model that marries many of the desirable features of compact smart chargers with foolproof older technology.

On the plus side, that means dedicated cycles for battery reconditioning and  6 volt, AGM, Gel, and Calcium battery technologies. Better still, the unit has limited jump start capabilities – supplying up to 150 Amps for 3 seconds – to awaken dead cars fast.

Sadly all of this is marred by other things we take for granted with modern chargers being absent, including weatherproof construction – meaning charging should always be done inside – and the lack of a hard-wired battery lead.

1. NOCO Genius5UK - BEST BUY

Smart Battery Chargers 2021 - NOCO Genius5UK

Price: £70.00
Buy from: Amazon or www.halfords.com
Contact: 01394 604040
Online: www.no.co
Overall score: 5/5
Suitable battery capacities: up to 120Ah

It's not quite as all-conquering as its Genius10 sibling, but this charger delivers exactly what most users will ever need at a more appealing price. Its top-spot position is all the more assured by that price undercutting its nearest rival, CTEK's CT5, by nearly a tenner.

Like the Genius10, dedicated modes ensure fast and efficient charging of standard 6 and 12 volt batteries, plus AGM and lithium technologies.

Again, the Genius5 works well with really desperate batteries, automatically detecting those with as little as 1 volt charge left and giving the option of forcing current into even more dilapidated ones.

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