Best jump starters 2021

Our cars have been spending a lot of time sitting stationary of late, which can easily lead to a flat battery. So, here we name the best jump starters you can buy...

2021 Jump starters - lead image

Lockdowns have taught us all many things, but for a fair few motorists it was that today’s cars don’t take much more than 4-6 weeks of being laid up to run their batteries completely flat.

And that’s normal: a plethora of internal memories, security systems, and devices constantly “listening” out for key fobs/cards continually leach power. Unsurprisingly, demand for Jump Starters went skyward as life temporarily returned towards normality.

Fortunately modern lithium battery-based jump starters are compact and lightweight, and can even double up as an everyday USB charger in some cases. But traditional big heavy lead/acid starters remain popular too. In this test we compare both types, and a third emerging technology. 

We make sure real life performance mirrors manufacturers’ output and capacity claims, before appraising features. Power outputs – whether USB, 12-volt “cigarette lighter” sockets, or even mains sockets – make an expensive piece of kit more than just something to start your engine. It’s a benefit, too, if a unit can be charged on the go, either by a USB or a 12-volt lead. This means a car with a failing battery, but okay charging system, remains usable until a battery swap is possible.

Audi A3 long termer

We prefer models with built-in safety features and alerts, to warn against wrongful connection, dead shorts, and a low charge on the car battery, when being used as a jump starter. Such alerts may just save you damaging your jump starter and your car’s delicate electronics.

Finally, we factor in value for money and ease of use. A bright light is a double bonus: it’s a lifesaver if you have to connect up in the dark, and it makes a great warning beacon if you become stuck at the side of the road.

Booster lead length is important too. While compact packs can normally be stashed somewhere under the bonnet during starting attempts, longer leads obviously allow more positioning flexibility. Heavier lead/acid boosters should be left on the ground, meaning their leads need to reach up to the battery for safe operation.

Our last usability consideration is maintenance charging. A booster is only as good as its internal charge, but it’s easy to forget to regularly top up the unit if it’s not being used. Bank on doing this every couple of months with lead/acid models, and check manufacturer’s guidelines with lithium packs.

Differing lithium technologies, such as Lithium Polymer or Lithium Carbonate, have their own requirements, with some needing nothing more than a six monthly top up.

 Top 10 jump starters for cars

10. Clarke Jump Start 4000

Jump starter - Clarke Jump Start

Price: £167.98
Buy from: Amazon or www.machinemart.co.uk
Contact: 01992 565333
Online: www.clarkeinternational.com
Overall score: 2/5
Manufacturer’s recommendation: Petrol  up to 6.0 litres, diesel up to 4.0 litres

Our first traditional jump starter is a real heavyweight. With a whopping 40Ah battery, and a cranking current that peaks at 2200 amps, there are few cars and vans this booster won't resuscitate – even if several start attempts are needed.

But, at 17kg, this is also heavy in an arm stretching sense. And, frankly, the unit feels sparse for its premium price tag. There’s just one accessory output – a 12 volt cigarette lighter socket – and none of the usual safety features are included.

Even the light is dated: a feeble and fragile incandescent bulb rather than an LED pack.

9. Silverline 684786

Jump starter - Silverline

Price: £57.00
Buy from: www.ffx.co.uk
Contact: 01935 382252
Online: www.silverlinetools.com
Overall score: 3/5
Manufacturer’s recommendation: Petrol up to 2.5 litres, diesel up to 2.0 Litres

This is a great alternative to our Best Budget Buy, and the cheapest compact booster here. With the usual slew of safety features, and surprisingly punchy starting performance, it makes a nonsense of taking a risk on those cheap unbranded lithium packs on internet auction sites.

At 6Ah, the internal battery has less stamina than many here, but that's only a problem if you intend many starting attempts between charges.

Feature wise you get the usual bright LED torch, two USB sockets (1 and 2.1 amps) and leads that cater for Micro USB, USB C, and Apple's Lightning ports.

8. Sealey Schumacher SL65S

Jump starter - Sealey Schumacher

Price: £84.95
Buy from: www.tooled-up.com
Contact: 01284 757500
Online: www.sealey.co.uk
Overall score: 3/5
Manufacturer’s recommendation: Petrol up to 2.0 litres, diesel up to 1.6 litres 

Several products have been close, but this is the first that's genuinely compact and light enough to replace an everyday USB charger. At 13.5x8.5x2.5cm, it feels like a short, stubby smartphone and fits easily into a pocket or glovebox.

With 8Ah capacity and two USB outputs  (1 and 2.1 Amps) it'll make short work of brimming your phone and other gadgets.

Predictably enough, the compact form reduces starting performance, but most smaller-engined petrol and diesel cars are fair game. Recommended monthly charging is our biggest niggle.

7. Sealey E/Start800

Jump starter - Sealey

Price: £161.94
Buy from: Amazon or www.eurocarparts.com
Contact: 01284 757500
Online: www.sealey.co.uk
Overall score: 3/5
Manufacturer’s recommendation: Petrol up to 3.0 litres, diesel up to 2.0 litres

Sealey’s E/Start range is battery less. And, bizarrely, Sealey suggests using your car’s dead battery to energise the unit! Stranger still, this seemingly bonkers approach works well. 

That’s because a “flat battery” usually has plenty of reserve power, even it its voltage has dropped too low to power automotive components.

The E/Start 800 feeds off this reserve energy (or another battery or USB source) for a couple of minutes to energise itself, so maintenance charging is never needed. The flip side is that no internal battery means no USB outputs or light.

6. Laser 7405

Jump starter - Laser

Price: £103.32
Buy from: www.thetoolacademycom
Contact: 01926 815000
Online: www.lasertools.co.uk
Overall score: 3/5
Manufacturer’s recommendation: Petrol up to 4.5 litres, diesel up to 3.5 litres

If this was only marginally smaller it would be a true dual purpose buy: a replacement for your everyday USB charger which is able to revive your car as well.

There are three USB outputs. The two full sized sockets kick out up to 2.1 amps, and the third – a USB C port, which also doubles as the charge input – can supply a whopping 3 amps.

Starting performance is excellent, with the higher price reflecting a slightly raised output compared with the our award winners. But top-up charging is required every 2-3 months, and the booster leads are a touch short.

5. Halfords Essentials 4 in 1 Jump Starter - BEST BUDGET BUY

Jump Starters - 2021 Best Budget Buy

Price: £50.00
Buy from: www.halfords.com
Contact: 0330 135 9779
Online: www.halfords.com
Overall score: 3/5
Manufacturer’s recommendation: Petrol and diesel up to 2.0 litres

Price is another reason why lead/acid boosters are still relevant. This unit's engine cranking power slightly lags our two other award winners, but its reserve capacity is better than both and it's significantly cheaper.

For a traditional unit, it's pretty easy to live with – noticeably smaller than the Clarke and Draper leviathans, and its 6kg weight is heavy rather than straining.

But it is a cheapie, so safety aids like low battery, incorrect correction, or dead short warnings are omitted. And you will need to top-up-charge bi-monthly, using mains or 12-volts rather than USB.

4. Draper 70554

Jump starter - Draper

Price: £196.00
Buy from: Amazon or www.lawson-his.co.uk
Contact: 023 8049 4333
Online: www.drapertools.com
Overall score: 3/5
Manufacturer’s recommendation: Not stated

Compared with the lithium packs, this is enormous and heavy – weighing 13.5Kg – but it successfully makes the case for lead/acid technology not being obsolete just yet.

With up to 1200 Amps on hand (3000 Amps Peak) there are few engines this unit cannot rouse. And even smaller commercials are catered for by the unit's switchable 12 or 24 volts output.

At 12 volts, the two internal batteries supply a huge 40 amp hours of capacity in total – giving a massive reserve for the 2.1 Amp USB socket, the two 12-volt sockets, and even the inverter driven mains sockets (300 watt maximum).

3. Clarke JSM350

Jump starter - Clarke

Price: £101.99
Buy from: Amazon or www.machinemart.co.uk
Contact: 01992 565333
Online: www.clarkeinternational.com
Overall score: 3/5
Manufacturer’s recommendation: Petrol up to 6.0-litres, diesel up to 3.0-litres

Accessories wise, this left field entry is unbeatable. Two 2.1 Amp USB sockets handle tech top ups, Lightening and 28-pin plugs – for Apple users – join the ubiquitous Mini and Micro USB plugs supplied, and a lead with various jack plug ends utilises separate 12 or 19 volt outputs to power countless 12 volt accessories and most laptops. It’s a good job the 18Ah internal battery has plenty of reserve as well as delivering excellent starting performance.

Recommended top-up charging every three months is a drawback, though, especially given that charging is via mains or 12-volts rather than USB.

2. Ring RPPL300 - RECOMMENDED

Jump starters 2021 - recommended

Price: £89.98
Buy from: www.toolstation.co.uk
Contact: 0113 213 2000
Online: www.ringautomotive.com
Overall score: 4/5
Manufacturer’s recommendation: Petrol and diesel, up to 3.0-litres

Ring's RPPL300 and our overall winner are a cut above in terms of finish and build quality. However, the RPPL300 just isn't quite as intuitive to use.

It's far from complex to operate but the polarity, low battery, and other warnings are relegated to a couple of tiny LEDs on the booster cable connector. And all other functions are accessed by a single button.

More impressive is the punchy starting power and the twin USB outputs. Both are 2.4 amps, ensuring rapid tech/phone charging. Sadly, the unit is a touch too big to sit in a pocket and make a separate USB charger redundant.

1. Noco Boost Sport GB20 - OVERALL BEST BUY

Jump starters 2021 - winner

Price: £79.00
Buy from: Amazon or www.halfords.com
Online: www.no.co
Overall score: 5/5
Manufacturer’s recommendation: Petrol up to 4.0-litres, diesel – not stated

Noco's Jump Starters are fast becoming as popular over here as they are on the other side of the Atlantic – and with their winning combination of solid performance, safety, and foolproof ease of use, it's not hard to see why.

Important warnings for incorrect cable correction, electrical shorts, and the vehicle's battery being excessively low on charge are clearly flagged up on the unit itself.

Similarly, the bright LED torch and the override mode are simply controlled by dedicated buttons. At nearly a foot long, the booster cables allow a bit more positioning flexibility than most rivals, too. A brilliant all-rounder.

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