Portable Battery Boxes
why the're still one of the best
dual battery solutions

Today, portable battery boxes are everywhere. Whether you're powering a fridge, charging devices or running camp lighting, there are countless battery boxes and portable power stations on the market.

But did you know the portable battery box concept has been around for much longer than most people realise?

It All Started With a Problem

Back in 2009, Totally 12 Volt owner Shane Adams recognised a growing issue within the automotive industry.

Four-wheel drives and passenger vehicles were becoming more compact, leaving little or no room under the bonnet for a traditional auxiliary battery.

For years, fitting a second battery under the bonnet had been the standard solution, but modern vehicle design was making this increasingly difficult.

Rather than seeing it as a limitation, Shane developed an alternative—a portable battery box that delivered all the benefits of a dual battery system without requiring a permanent under-bonnet installation.

It was a simple idea that solved several problems at once.

A Cooler Battery Is a Happier Battery

At the time, AGM batteries were the preferred choice for deep-cycle applications, as lithium batteries were still years away from becoming mainstream.

One of the biggest disadvantages of AGM batteries was heat.

Although they're completely sealed and maintenance-free, AGM batteries don't particularly like the high temperatures found under the bonnet. Constant engine bay heat can reduce battery performance and shorten service life.

By relocating the battery inside the vehicle, the battery operated in a much cooler environment, improving reliability and helping maximise battery life.

Today, with lithium batteries becoming the preferred choice, the benefits are even greater. Lithium batteries also perform best when protected from excessive heat, making an internal battery installation an excellent long-term solution.

More Than Just a Battery Box

One of the biggest advantages of a portable battery box is flexibility.

We've had customers use the same battery box across multiple vehicles for years.

Each vehicle is fitted with charging cables connected to the starting battery and terminated with an Anderson plug in the cargo area.

The battery box simply plugs in when required and disconnects just as easily.

If you change vehicles, there's no need to purchase another battery system. The battery box simply transfers to your new vehicle, making it a smart long-term investment.

Portable battery boxes also allow you to move your power source closer to camp, making it easier to run fridges, lighting and camping accessories exactly where you need them.

The REDARC Revolution

As battery technology evolved, so did portable battery systems.

The introduction of REDARC DC-DC chargers completely changed what a battery box could do.

Rather than simply charging from the alternator through basic isolators, a DC-DC charger provides the correct charging profile for AGM and lithium batteries while overcoming voltage drop and the challenges of modern smart alternators.

At Totally 12 Volt, we integrate REDARC DC-DC chargers into our battery boxes, with an additional solar input allowing the same charger to operate as a solar controller.

This creates a true dual battery system capable of charging from:

Your vehicle while driving

Portable solar panels

Fixed solar panels

240V battery chargers

A True Dual Battery System

There's an important difference between a professionally built portable battery box and many all-in-one portable power stations.

Products like the Bluetti range certainly have their place and are ideal for many users. However, they generally rely on charging from mains power or dedicated AC chargers to achieve their fastest charging rates. When charging directly from a vehicle, charging speeds can be significantly slower depending on the model and charging method.

A professionally built battery box with a quality REDARC DC-DC charger is designed specifically as a true dual battery system, allowing efficient charging from your vehicle while you drive, with the added flexibility of integrated solar charging.

For travellers who spend extended periods on the road, this means more usable power and less time waiting for batteries to recharge.

The 12 Volt Mate Goes Global

The portable battery box concept didn't stop in Australia.

Shane later developed a heavy-duty version known as the 12 Volt Mate, designed for harsh conditions and serious touring.

The rugged design proved so popular that the 12 Volt Mate was exported and sold throughout the United States, where it was well received by customers looking for a reliable portable power solution.

It was another example of Australian-designed innovation finding success on the international stage.

Is a Portable Battery Box Right for You?

Portable battery boxes continue to be one of the most practical dual battery solutions available.

They're ideal for people who:

Own multiple vehicles.

Regularly upgrade their vehicle.

Want portable power around the campsite.

Need a reliable dual battery system without major vehicle modifications.

Want the flexibility of charging from both the vehicle and solar.

Totally 12 Volt, we've been designing and building battery systems for more than 15 years. They will help you choose the right solution based on how you travel—not simply sell you the biggest battery.

Whether you're heading off for a weekend away or planning the lap of Australia, Totally 12 Volt can build a battery system that's reliable, efficient and ready for the adventure ahead.

article by Shane Adams




 

August 2026