Many of us have seen the charger that will jump start your car, charge your mobile and fit in your bag or glovebox. If you have ever left your lights on or ran your battery flat whilst listening to your favourite tunes this could be the perfect device for you.

Usually, these types of jump packs use compact polymer/cobalt battery cells, which take up far less room in your vehicle than a typical jump battery pack. On the market we found two popular models, a 400amp unit which would set you back $200 and a 600amp jump pack that costs $220, supplied through a reputable retailer.

The 400amp model is perfect for smaller four-cylinder, petrol models while the larger 600amp packs offers even better results for harder to start diesel models. The higher compression ratio and increased starter motor draw means that diesel vehicles require a stronger battery to turn the engine over.

What you need to know

These products work well when the instructions are followed and when the device is fully charged. However, you could face a few potential issues if instructions are not followed. For example if your battery was flat and you connected the polarity incorrectly, and if you are to use the override function, you can damage sensitive electronic components. The override feature bypasses the built-in safety features on the device. We always recommend adhering to the instructions diligently.

For occasional use, the jump packs from a reputable brand with clear instructions perform well. The only maintenance they require is keeping them charged. They also offer other benefits, such as being able to charge mobile devices on the go from the integrated USB charging ports. They incorporate a long-lasting LED flashlight, which is a welcome addition to any emergency kit. But there’s still nothing that matches AA Roadservice and breakdown assistance when it comes to getting your vehicle started on the side of the road.

Often vehicles don’t just need to be jump started, a diagnostic check should be carried out to determine what has caused the issue in the first place, and how to prevent another flat battery in the future. These answers are best left to our skilled AA Roadservice team.

Once you have jump started you will be fine, right?

While recharging your car battery using the alternator might seem like the easy solution, it’s not really a good one. Remember that the alternator is only designed to supply enough power to maintain your battery charge level and power your car. This is a much bigger ask to totally recharge a dead battery which requires a very high continuous current.

Even taking your vehicle out for a long drive won’t fully charge your battery, and the only way to do this is with a proper battery charger.

Remember that trying to charge a flat battery puts quite a lot of extra strain on your alternator, which isn’t designed to supply such a large current for an extended duration.

It is okay to do it once in a while in an emergency. If your battery is continuously weak and you are just avoiding a full charge or a battery replacement, it could reduce your alternator working life and also cost you more in fuel and performance if your alternator is always under unnecessary load.

A weak battery can also prematurely wear your starter motor. As the voltage supplied from a weak battery drops, it requires a higher current to compensate. The starter motor wasn’t designed for the higher current, and you can easily damage it.

If you are unsure of your battery’s condition we recommend a load test, this can be done at one of our AA Auto Centres, especially if your car is turning over a bit slower than usual.

You can always purchase a quality charger here at our AA shop, it’s great to have one of these on hand if you inadvertently leave accessories on at home.

How the AA can help 

• AA Auto Centre - aa.co.nz/autocentre 
• AA Pre Purchase Inspections - aa.co.nz/inspections
• AA Motoring Vehicle Inspection - aa.co.nz/wof
• AA 10-Point Check - aa.co.nz/10-point-check
• AA Batteries - aa.co.nz/batteries
• AA Memebership - aa.co.nz/membership
• AA Roadservice - aa.co.nz/roadservice
  
• AA Ask an Expert - aa.co.nz/cars/ask-an-expert
  

Vehicle experts you can trust