I mentioned above that DC-DC chargers are not all the same. There’s a few things that you should consider before laying your hard earned coin out:

Is it a good quality unit?

Like anything in life, you can buy the cheapest DC to DC charger and hope for the best, or you can buy the most expensive one out there and expect it will last a long time. We generally fall in the middle, but always look for reviews from real life owners to see what they think of it.

Some have fantastic reputations and are highly recommended, and others are 50/50 as to whether you’ll have issues in the first few years!

What battery types will it work for?

When we purchased our Projecta DCDC, I never thought about the possibility of fitting lithium in the future.

It’s not a lithium compatible DCDC (they do sell them now though), which means when our AGM finally dies and we go to lithium (which we’ve now purchased but not installed) I’ll not only have to change the battery, but I’ll need a new DCDC too.

Have a think about how long you plan on using the charger for, and whether it does the different chemistries that you are likely to run.

What’s its maximum charge rate?

One of the most important things to think about is the maximum charge that the DCDC can do. Some are capped at 15 amps, whilst others are capped at 25, 30, 40 and even 50 amp.

If you get an undersized DCDC, you’ll have to drive for hours every day to charge your batteries up, as they are literally capped at the maximum charge rate. On the other side of the coin, don’t get one that will damage your batteries because its too big for your setup.

Can you adjust any settings?

Going on from the above point, being able to adjust the settings is magic, and some DCDC chargers do this very, very well. Our Enerdrive DC2DC for example, is as customisable as it gets, and is one of the reasons I seriously rate it.

Not only will it do any battery type (including lithium), but you can adjust the maximum charge rate and a whole heap of other settings based on your requirements.

I’ve bumped the charge rate up a little for our two AGM batteries when we were struggling to keep up a while back, and when we move to lithium I’ll change it to the lithium profile and bump it to maximum charge (if the cables are rated for it!).

A DCDC that you cannot adjust any settings on can be extremely frustrating, and in many ways restrictive, and even sometimes plain useless.